| Message ID | 1428736145-18361-3-git-send-email-sricharan@codeaurora.org |
|---|---|
| State | Changes Requested |
| Headers | show |
Hi Sricharan, On Sat, 2015-04-11 at 12:39 +0530, Sricharan R wrote: > From: Andy Gross <agross@codeaurora.org> > > QUP from version 2.1.1 onwards, supports a new format of > i2c command tags. Tag codes instructs the controller to > perform a operation like read/write. This new tagging version > supports bam dma and transfers of more than 256 bytes without 'stop' > in between. Adding the support for the same. > But the read and write messages size QUP_READ_LIMIT? > For each block a data_write/read tag and data_len tag is added to > the output fifo. For the final block of data write_stop/read_stop > tag is used. > > Signed-off-by: Andy Gross <agross@codeaurora.org> > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > --- > [V3] Addressed comments from Andy Gross <agross@codeaurora.org> > to coalesce each i2c_msg in i2c_msgs as a single transfer. > Added macros to i2c_wait_ready function. > > drivers/i2c/busses/i2c-qup.c | 393 +++++++++++++++++++++++++++++++++++++------ > 1 file changed, 337 insertions(+), 56 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c > index 9ccf3e8..16a8f69 100644 > --- a/drivers/i2c/busses/i2c-qup.c > +++ b/drivers/i2c/busses/i2c-qup.c > @@ -24,6 +24,7 @@ > #include <linux/of.h> > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > +#include <linux/slab.h> > > /* QUP Registers */ > #define QUP_CONFIG 0x000 > @@ -42,6 +43,7 @@ > #define QUP_IN_FIFO_BASE 0x218 > #define QUP_I2C_CLK_CTL 0x400 > #define QUP_I2C_STATUS 0x404 > +#define QUP_I2C_MASTER_GEN 0x408 > > /* QUP States and reset values */ > #define QUP_RESET_STATE 0 > @@ -69,6 +71,8 @@ > #define QUP_CLOCK_AUTO_GATE BIT(13) > #define I2C_MINI_CORE (2 << 8) > #define I2C_N_VAL 15 > +#define I2C_N_VAL_V2 7 > + > /* Most significant word offset in FIFO port */ > #define QUP_MSW_SHIFT (I2C_N_VAL + 1) > > @@ -80,17 +84,30 @@ > > #define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN) > > +#define QUP_V2_TAGS_EN 1 > + > #define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03) > #define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07) > #define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03) > #define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07) > > -/* QUP tags */ > +/* QUP V1 tags */ > #define QUP_TAG_START (1 << 8) > #define QUP_TAG_DATA (2 << 8) > #define QUP_TAG_STOP (3 << 8) > #define QUP_TAG_REC (4 << 8) > > +/* QUP v2 tags */ > +#define QUP_TAG_V2_HS 0xff > +#define QUP_TAG_V2_START 0x81 > +#define QUP_TAG_V2_DATAWR 0x82 > +#define QUP_TAG_V2_DATAWR_STOP 0x83 > +#define QUP_TAG_V2_DATARD 0x85 > +#define QUP_TAG_V2_DATARD_STOP 0x87 > + > +/* frequency definitions for high speed and max speed */ > +#define I2C_QUP_CLK_FAST_FREQ 1000000 This is fast mode, if I am not mistaken. > + > /* Status, Error flags */ > #define I2C_STATUS_WR_BUFFER_FULL BIT(0) > #define I2C_STATUS_BUS_ACTIVE BIT(8) > @@ -102,6 +119,15 @@ > #define RESET_BIT 0x0 > #define ONE_BYTE 0x1 > > +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) Could you explain what is this for? > + > +struct qup_i2c_block { > + int blocks; > + u8 *block_tag_len; > + int *block_data_len; > + int block_pos; > +}; > + > struct qup_i2c_dev { > struct device*dev; > void __iomem*base; > @@ -115,9 +141,17 @@ struct qup_i2c_dev { > int in_fifo_sz; > int out_blk_sz; > int in_blk_sz; > - > + struct qup_i2c_blockblk; > unsigned longone_byte_t; > > + int is_hs; > + bool use_v2_tags; > + > + int tx_tag_len; > + int rx_tag_len; > + u8 *tags; > + int tags_pos; > + > struct i2c_msg*msg; > /* Current posion in user message buffer */ > int pos; > @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, > } > } Is this better tag related fields grouping? struct qup_i2c_tag_block { u8 tag[2]; // int tag_len; this is alway 2, or? int data_len; // this could be zero, right? }; > > -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, > + int run) And 'run' stands for? > { > - /* Number of entries to shift out, including the start */ > - int total = msg->len + 1; > + /* Total Number of entries to shift out, including the tags */ > + int total; > + > + if (qup->use_v2_tags) { > + total = msg->len + qup->tx_tag_len; > + if (run) > + total |= QUP_I2C_MX_CONFIG_DURING_RUN; What? > + } else { > + total = msg->len + 1; /* plus start tag */ > + } > > if (total < qup->out_fifo_sz) { > /* FIFO mode */ > @@ -280,7 +323,7 @@ static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg > *msg) > } > } > > -static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_issue_write_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) > { > u32 addr = msg->addr << 1; > u32 qup_tag; > @@ -321,7 +364,136 @@ static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg > *msg) > } > } > > -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, > + struct i2c_msg *msg, int last) > +{ > + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); > + int len = 0, prev_len = 0; > + int blocks = 0; > + int rem; > + int block_len = 0; > + int data_len; > + > + qup->blk.block_pos = 0; > + qup->pos = 0; > + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; > + rem = msg->len % QUP_READ_LIMIT; > + > + /* 2 tag bytes for each block + 2 extra bytes for first block */ > + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); > + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); > + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * > + qup->blk.blocks, GFP_KERNEL); Whouldn't be easy to kcalloc struct qup_i2c_tag_block? Allocations could fail and memory is leaking here. > + > + while (blocks < qup->blk.blocks) { > + /* 0 is used to specify a READ_LIMIT of 256 bytes */ > + data_len = (blocks < (qup->blk.blocks - 1)) ? 0 : rem; > + > + /* Send START and ADDR bytes only for the first block */ > + if (!blocks) { > + qup->tags[len++] = QUP_TAG_V2_START; > + > + if (qup->is_hs) { > + qup->tags[len++] = QUP_TAG_V2_HS; > + qup->tags[len++] = QUP_TAG_V2_START; > + } > + > + qup->tags[len++] = addr & 0xff; > + if (msg->flags & I2C_M_TEN) > + qup->tags[len++] = addr >> 8; I have counted 5 bytes for first block? > + } > + > + /* Send _STOP commands for the last block */ > + if ((blocks == (qup->blk.blocks - 1)) && last) { > + if (msg->flags & I2C_M_RD) > + qup->tags[len++] = QUP_TAG_V2_DATARD_STOP; > + else > + qup->tags[len++] = QUP_TAG_V2_DATAWR_STOP; > + } else { > + if (msg->flags & I2C_M_RD) > + qup->tags[len++] = QUP_TAG_V2_DATARD; > + else > + qup->tags[len++] = QUP_TAG_V2_DATAWR; > + } > + > + qup->tags[len++] = data_len; > + block_len = len - prev_len; > + prev_len = len; > + qup->blk.block_tag_len[blocks] = block_len; > + > + if (!data_len) > + qup->blk.block_data_len[blocks] = QUP_READ_LIMIT; > + else > + qup->blk.block_data_len[blocks] = data_len; > + > + qup->tags_pos = 0; Every time? > + blocks++; Looks like 'for' cycle to me. > + } > + > + qup->tx_tag_len = len; > + > + if (msg->flags & I2C_M_RD) > + qup->rx_tag_len = (qup->blk.blocks * 2); > + else > + qup->rx_tag_len = 0; > +} > + > +static u32 qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf, > + int dlen, u8 *dbuf) > +{ > + u32 val = 0, idx = 0, pos = 0, i = 0, t; > + int len = tlen + dlen; > + u8 *buf = tbuf; > + > + while (len > 0) { > + if (qup_i2c_wait_ready(qup, QUP_OUT_FULL, 0, 4)) { > + dev_err(qup->dev, "timeout for fifo out full"); > + break; Error not propagated? > + } > + > + t = (len >= 4) ? 4 : len; > + > + while (idx < t) { > + if (!i && (pos >= tlen)) { > + buf = dbuf; > + pos = 0; > + i = 1; > + } > + val |= buf[pos++] << (idx++ * 8); > + } > + > + writel(val, qup->base + QUP_OUT_FIFO_BASE); > + idx = 0; > + val = 0; > + len -= 4; > + } > + > + return 0; > +} > + > +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +{ > + u32 data_len = 0, tag_len; > + > + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; > + > + if (!(msg->flags & I2C_M_RD)) > + data_len = qup->blk.block_data_len[qup->blk.block_pos]; > + > + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); This assumes that writes are up to 256 bytes, and tags and data blocks are completely written to FIFO buffer, right? > +} > + > +static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg > + *msg) > +{ > + if (qup->use_v2_tags) > + qup_i2c_issue_xfer_v2(qup, msg); > + else > + qup_i2c_issue_write_v1(qup, msg); > +} > + > +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, > + int run, int last) > { > unsigned long left; > int ret; > @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > qup->msg = msg; > qup->pos = 0; > > + if (qup->use_v2_tags) > + qup_i2c_create_tag_v2(qup, msg, last); > + else > + qup->blk.blocks = 0; > + > enable_irq(qup->irq); > > - qup_i2c_set_write_mode(qup, msg); > + qup_i2c_set_write_mode(qup, msg, run); > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > - if (ret) > - goto err; > + if (!run) { > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); To run away, or not? > + if (ret) > + goto err; > + } > > writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); > > @@ -363,10 +542,13 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > ret = -EIO; > goto err; > } > - } while (qup->pos < msg->len); > + qup->blk.block_pos++; > + } while (qup->blk.block_pos < qup->blk.blocks); > > /* Wait for the outstanding data in the fifo to drain */ > - ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE); > + if (last) > + ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, > + ONE_BYTE); > > err: > disable_irq(qup->irq); > @@ -375,8 +557,17 @@ err: > return ret; > } > > -static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) > +static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len, int run) > { > + if (qup->use_v2_tags) { > + len += qup->rx_tag_len; > + if (run) { > + len |= QUP_I2C_MX_CONFIG_DURING_RUN; Again? It looks like some kind of magic, to trick the controller that there are more bytes to transfer, or? > + qup->tx_tag_len |= QUP_I2C_MX_CONFIG_DURING_RUN; > + } > + writel(qup->tx_tag_len, qup->base + QUP_MX_WRITE_CNT); > + } > + > if (len < qup->in_fifo_sz) { > /* FIFO mode */ > writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); > @@ -389,7 +580,8 @@ static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) > } > } > > -static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_issue_read_v1(struct qup_i2c_dev *qup, > + struct i2c_msg *msg) > { > u32 addr, len, val; > > @@ -402,20 +594,28 @@ static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) > writel(val, qup->base + QUP_OUT_FIFO_BASE); > } > > +static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg > + *msg) > +{ > + if (qup->use_v2_tags) > + qup_i2c_issue_xfer_v2(qup, msg); > + else > + qup_i2c_issue_read_v1(qup, msg); > +} > > -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) > { > - u32 opflags; > u32 val = 0; > int idx; > + int len = msg->len + qup->rx_tag_len; Is this intentional? > > - for (idx = 0; qup->pos < msg->len; idx++) { > + for (idx = 0; qup->pos < len; idx++) { > if ((idx & 1) == 0) { > /* Check that FIFO have data */ > - opflags = readl(qup->base + QUP_OPERATIONAL); > - if (!(opflags & QUP_IN_NOT_EMPTY)) > + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { This should be part of the first patch. > + dev_err(qup->dev, "timeout for fifo not empty"); > break; > - > + } > /* Reading 2 words at time */ > val = readl(qup->base + QUP_IN_FIFO_BASE); > > @@ -426,11 +626,50 @@ static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) > } > } > > -static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > +static void qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup, > + struct i2c_msg *msg) > +{ > + u32 val; > + int idx; > + int pos = 0; > + /* 2 extra bytes for read tags */ > + int total = qup->blk.block_data_len[qup->blk.block_pos] + 2; > + > + while (pos < total) { > + /* Check that FIFO have data */ > + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { > + dev_err(qup->dev, "timeout for fifo not empty"); > + break; Error not propagated. > + } > + val = readl(qup->base + QUP_IN_FIFO_BASE); > + > + for (idx = 0; idx < 4; idx++, val >>= 8, pos++) { > + /* first 2 bytes are tag bytes */ > + if (pos < 2) > + continue; > + > + if (pos >= total) > + return; > + > + msg->buf[qup->pos++] = val & 0xff; > + } > + } > +} > + > +static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, > + struct i2c_msg *msg) > +{ > + if (qup->use_v2_tags) > + qup_i2c_read_fifo_v2(qup, msg); > + else > + qup_i2c_read_fifo_v1(qup, msg); > +} > + > +static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, > + int run, int last) > { > unsigned long left; > int ret; > - > /* > * The QUP block will issue a NACK and STOP on the bus when reaching > * the end of the read, the length of the read is specified as one byte > @@ -444,28 +683,34 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > qup->msg = msg; > qup->pos = 0; > + if (qup->use_v2_tags) > + qup_i2c_create_tag_v2(qup, msg, last); > + else > + qup->blk.blocks = 0; > > enable_irq(qup->irq); > > - qup_i2c_set_read_mode(qup, msg->len); > + qup_i2c_set_read_mode(qup, msg->len, run); > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > - if (ret) > - goto err; > + if (!run) { > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); If !run, place controller in RUN state? > + if (ret) > + goto err; > + } > > writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); > > - ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); > - if (ret) > - goto err; > + do { > + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); > + if (ret) > + goto err; > > - qup_i2c_issue_read(qup, msg); > + qup_i2c_issue_read(qup, msg); > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > - if (ret) > - goto err; > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > + if (ret) > + goto err; > > - do { > left = wait_for_completion_timeout(&qup->xfer, HZ); > if (!left) { > writel(1, qup->base + QUP_SW_RESET); > @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > } > > qup_i2c_read_fifo(qup, msg); > - } while (qup->pos < msg->len); > + qup->blk.block_pos++; This should not be incremented, unless we really have read this block. > + } while (qup->blk.block_pos < qup->blk.blocks); > > err: > disable_irq(qup->irq); > @@ -495,7 +741,7 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, > int num) > { > struct qup_i2c_dev *qup = i2c_get_adapdata(adap); > - int ret, idx; > + int ret, idx, last; > > ret = pm_runtime_get_sync(qup->dev); > if (ret < 0) > @@ -507,7 +753,12 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, > goto out; > > /* Configure QUP as I2C mini core */ > - writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); > + if (qup->use_v2_tags) { > + writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG); > + writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); > + } else { > + writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); > + } > > for (idx = 0; idx < num; idx++) { > if (msgs[idx].len == 0) { > @@ -520,23 +771,32 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, > goto out; > } > > + reinit_completion(&qup->xfer); > + > + last = (idx == (num - 1)); > + > if (msgs[idx].flags & I2C_M_RD) > - ret = qup_i2c_read_one(qup, &msgs[idx]); > + ret = qup_i2c_read_one(qup, &msgs[idx], idx, last); > else > - ret = qup_i2c_write_one(qup, &msgs[idx]); > + ret = qup_i2c_write_one(qup, &msgs[idx], idx, last); > > if (ret) > break; > + } > > + if (!ret) > ret = qup_i2c_change_state(qup, QUP_RESET_STATE); > - if (ret) > - break; > - } > > if (ret == 0) > ret = num; > out: > > + if (qup->use_v2_tags) { > + kfree(qup->tags); > + kfree(qup->blk.block_tag_len); > + kfree(qup->blk.block_data_len); > + } > + > pm_runtime_mark_last_busy(qup->dev); > pm_runtime_put_autosuspend(qup->dev); > > @@ -559,6 +819,14 @@ static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup) > clk_prepare_enable(qup->pclk); > } > > +static const struct of_device_id qup_i2c_dt_match[] = { > + { .compatible = "qcom,i2c-qup-v1.1.1"}, > + { .compatible = "qcom,i2c-qup-v2.1.1"}, > + { .compatible = "qcom,i2c-qup-v2.2.1"}, Space before closing brace, please. I am starting to think that it will be more readable if we just define qup_i2c_algo_v2 and use it, if controller is v2 and upwards? Ivan -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Ivan, On 04/14/2015 08:46 PM, Ivan T. Ivanov wrote: > > Hi Sricharan, > > On Sat, 2015-04-11 at 12:39 +0530, Sricharan R wrote: >> From: Andy Gross <agross@codeaurora.org> >> >> QUP from version 2.1.1 onwards, supports a new format of >> i2c command tags. Tag codes instructs the controller to >> perform a operation like read/write. This new tagging version >> supports bam dma and transfers of more than 256 bytes without 'stop' >> in between. Adding the support for the same. >> > > But the read and write messages size QUP_READ_LIMIT? > The READ_LIMIT is not true with the V2 tags. The controller can read/write multiple of 256 bytes sub-transfers to make transactions greater than > 256. Infact, i will have to remove the check for the READ_LIMIT in case of V2. I will add that. >> For each block a data_write/read tag and data_len tag is added to >> the output fifo. For the final block of data write_stop/read_stop >> tag is used. >> >> Signed-off-by: Andy Gross <agross@codeaurora.org> >> Signed-off-by: Sricharan R <sricharan@codeaurora.org> >> --- >> [V3] Addressed comments from Andy Gross <agross@codeaurora.org> >> to coalesce each i2c_msg in i2c_msgs as a single transfer. >> Added macros to i2c_wait_ready function. >> >> drivers/i2c/busses/i2c-qup.c | 393 +++++++++++++++++++++++++++++++++++++------ >> 1 file changed, 337 insertions(+), 56 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c >> index 9ccf3e8..16a8f69 100644 >> --- a/drivers/i2c/busses/i2c-qup.c >> +++ b/drivers/i2c/busses/i2c-qup.c >> @@ -24,6 +24,7 @@ >> #include <linux/of.h> >> #include <linux/platform_device.h> >> #include <linux/pm_runtime.h> >> +#include <linux/slab.h> >> >> /* QUP Registers */ >> #define QUP_CONFIG 0x000 >> @@ -42,6 +43,7 @@ >> #define QUP_IN_FIFO_BASE 0x218 >> #define QUP_I2C_CLK_CTL 0x400 >> #define QUP_I2C_STATUS 0x404 >> +#define QUP_I2C_MASTER_GEN 0x408 >> >> /* QUP States and reset values */ >> #define QUP_RESET_STATE 0 >> @@ -69,6 +71,8 @@ >> #define QUP_CLOCK_AUTO_GATE BIT(13) >> #define I2C_MINI_CORE (2 << 8) >> #define I2C_N_VAL 15 >> +#define I2C_N_VAL_V2 7 >> + >> /* Most significant word offset in FIFO port */ >> #define QUP_MSW_SHIFT (I2C_N_VAL + 1) >> >> @@ -80,17 +84,30 @@ >> >> #define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN) >> >> +#define QUP_V2_TAGS_EN 1 >> + >> #define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03) >> #define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07) >> #define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03) >> #define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07) >> >> -/* QUP tags */ >> +/* QUP V1 tags */ >> #define QUP_TAG_START (1 << 8) >> #define QUP_TAG_DATA (2 << 8) >> #define QUP_TAG_STOP (3 << 8) >> #define QUP_TAG_REC (4 << 8) >> >> +/* QUP v2 tags */ >> +#define QUP_TAG_V2_HS 0xff >> +#define QUP_TAG_V2_START 0x81 >> +#define QUP_TAG_V2_DATAWR 0x82 >> +#define QUP_TAG_V2_DATAWR_STOP 0x83 >> +#define QUP_TAG_V2_DATARD 0x85 >> +#define QUP_TAG_V2_DATARD_STOP 0x87 >> + >> +/* frequency definitions for high speed and max speed */ >> +#define I2C_QUP_CLK_FAST_FREQ 1000000 > > This is fast mode, if I am not mistaken. > ya, up to 1MHZ is fast and up to 3.4MHZ is HS. We use this macro to check if the desired freq is in HS range. The above comment can be changed though to make it clear. >> + >> /* Status, Error flags */ >> #define I2C_STATUS_WR_BUFFER_FULL BIT(0) >> #define I2C_STATUS_BUS_ACTIVE BIT(8) >> @@ -102,6 +119,15 @@ >> #define RESET_BIT 0x0 >> #define ONE_BYTE 0x1 >> >> +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) > > Could you explain what is this for? > This is a new feature in the V2 version of the controller, to support multiple i2c sub transfers without having a 'stop' bit in-between. Without this the i2c controller inserts a 'stop' on the bus when the WR/RD count registers reaches zero and are configured for the next transfer. So setting this bit when the controller is in 'RUN' state, avoids sending the 'stop' during RUN state. I can add this comment in the patch. >> + >> +struct qup_i2c_block { >> + int blocks; >> + u8 *block_tag_len; >> + int *block_data_len; >> + int block_pos; >> +}; >> + >> struct qup_i2c_dev { >> struct device*dev; >> void __iomem*base; >> @@ -115,9 +141,17 @@ struct qup_i2c_dev { >> int in_fifo_sz; >> int out_blk_sz; >> int in_blk_sz; >> - >> + struct qup_i2c_blockblk; >> unsigned longone_byte_t; >> >> + int is_hs; >> + bool use_v2_tags; >> + >> + int tx_tag_len; >> + int rx_tag_len; >> + u8 *tags; >> + int tags_pos; >> + >> struct i2c_msg*msg; >> /* Current posion in user message buffer */ >> int pos; >> @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, >> } >> } > > Is this better tag related fields grouping? > > struct qup_i2c_tag_block { > > u8 tag[2]; > // int tag_len; this is alway 2, or? > int data_len; // this could be zero, right? > }; > There is a struct for qup_i2c_block which has tag and data len. Not sure what change you suggest above ? Also with V2 transfers tag len need not be 2. It can be more than that based on the data len. >> >> -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, >> + int run) > > And 'run' stands for? 'run' just says whether the controller is in 'RUN' or 'RESET' state. I can change it to is_run_st to make it clear. > >> { >> - /* Number of entries to shift out, including the start */ >> - int total = msg->len + 1; >> + /* Total Number of entries to shift out, including the tags */ >> + int total; >> + >> + if (qup->use_v2_tags) { >> + total = msg->len + qup->tx_tag_len; >> + if (run) >> + total |= QUP_I2C_MX_CONFIG_DURING_RUN; > > What? > This means, if the controller is in 'RUN' state, for reconfiguring the RD/WR counts this bit has to be set to avoid 'stop' bits. >> + } else { >> + total = msg->len + 1; /* plus start tag */ >> + } >> >> if (total < qup->out_fifo_sz) { >> /* FIFO mode */ >> @@ -280,7 +323,7 @@ static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg >> *msg) >> } >> } >> >> -static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_issue_write_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> { >> u32 addr = msg->addr << 1; >> u32 qup_tag; >> @@ -321,7 +364,136 @@ static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg >> *msg) >> } >> } >> >> -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, >> + struct i2c_msg *msg, int last) >> +{ >> + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); >> + int len = 0, prev_len = 0; >> + int blocks = 0; >> + int rem; >> + int block_len = 0; >> + int data_len; >> + >> + qup->blk.block_pos = 0; >> + qup->pos = 0; >> + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; >> + rem = msg->len % QUP_READ_LIMIT; >> + >> + /* 2 tag bytes for each block + 2 extra bytes for first block */ >> + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); >> + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); >> + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * >> + qup->blk.blocks, GFP_KERNEL); > > Whouldn't be easy to kcalloc struct qup_i2c_tag_block? > > > Allocations could fail and memory is leaking here. > ya correct, will change this. Freeing is done at the end of xfer function, but will have to check for allocation failure. >> + >> + while (blocks < qup->blk.blocks) { >> + /* 0 is used to specify a READ_LIMIT of 256 bytes */ >> + data_len = (blocks < (qup->blk.blocks - 1)) ? 0 : rem; >> + >> + /* Send START and ADDR bytes only for the first block */ >> + if (!blocks) { >> + qup->tags[len++] = QUP_TAG_V2_START; >> + >> + if (qup->is_hs) { >> + qup->tags[len++] = QUP_TAG_V2_HS; >> + qup->tags[len++] = QUP_TAG_V2_START; >> + } >> + >> + qup->tags[len++] = addr & 0xff; >> + if (msg->flags & I2C_M_TEN) >> + qup->tags[len++] = addr >> 8; > > I have counted 5 bytes for first block? > Yes 5 bytes for TEN bit addresses or HS mode. So i will have to add extra bytes in the above allocation. Will change that. Thanks for pointing. >> + } >> + >> + /* Send _STOP commands for the last block */ >> + if ((blocks == (qup->blk.blocks - 1)) && last) { >> + if (msg->flags & I2C_M_RD) >> + qup->tags[len++] = QUP_TAG_V2_DATARD_STOP; >> + else >> + qup->tags[len++] = QUP_TAG_V2_DATAWR_STOP; >> + } else { >> + if (msg->flags & I2C_M_RD) >> + qup->tags[len++] = QUP_TAG_V2_DATARD; >> + else >> + qup->tags[len++] = QUP_TAG_V2_DATAWR; >> + } >> + >> + qup->tags[len++] = data_len; >> + block_len = len - prev_len; >> + prev_len = len; >> + qup->blk.block_tag_len[blocks] = block_len; >> + >> + if (!data_len) >> + qup->blk.block_data_len[blocks] = QUP_READ_LIMIT; >> + else >> + qup->blk.block_data_len[blocks] = data_len; >> + >> + qup->tags_pos = 0; > > Every time? > ok, infact unsed. Will remove it. >> + blocks++; > > Looks like 'for' cycle to me. > sorry, not getting it ? >> + } >> + >> + qup->tx_tag_len = len; >> + >> + if (msg->flags & I2C_M_RD) >> + qup->rx_tag_len = (qup->blk.blocks * 2); >> + else >> + qup->rx_tag_len = 0; >> +} >> + >> +static u32 qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf, >> + int dlen, u8 *dbuf) >> +{ >> + u32 val = 0, idx = 0, pos = 0, i = 0, t; >> + int len = tlen + dlen; >> + u8 *buf = tbuf; >> + >> + while (len > 0) { >> + if (qup_i2c_wait_ready(qup, QUP_OUT_FULL, 0, 4)) { >> + dev_err(qup->dev, "timeout for fifo out full"); >> + break; > > Error not propagated? > Ok, will change this and another place to return the err no correctly. >> + } >> + >> + t = (len >= 4) ? 4 : len; >> + >> + while (idx < t) { >> + if (!i && (pos >= tlen)) { >> + buf = dbuf; >> + pos = 0; >> + i = 1; >> + } >> + val |= buf[pos++] << (idx++ * 8); >> + } >> + >> + writel(val, qup->base + QUP_OUT_FIFO_BASE); >> + idx = 0; >> + val = 0; >> + len -= 4; >> + } >> + >> + return 0; >> +} >> + >> +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +{ >> + u32 data_len = 0, tag_len; >> + >> + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; >> + >> + if (!(msg->flags & I2C_M_RD)) >> + data_len = qup->blk.block_data_len[qup->blk.block_pos]; >> + >> + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); > > This assumes that writes are up to 256 bytes, and tags and data blocks > are completely written to FIFO buffer, right? > Yes, since we send/read data in blocks (256 bytes). >> +} >> + >> +static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg >> + *msg) >> +{ >> + if (qup->use_v2_tags) >> + qup_i2c_issue_xfer_v2(qup, msg); >> + else >> + qup_i2c_issue_write_v1(qup, msg); >> +} >> + >> +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, >> + int run, int last) >> { >> unsigned long left; >> int ret; >> @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> qup->msg = msg; >> qup->pos = 0; >> >> + if (qup->use_v2_tags) >> + qup_i2c_create_tag_v2(qup, msg, last); >> + else >> + qup->blk.blocks = 0; >> + >> enable_irq(qup->irq); >> >> - qup_i2c_set_write_mode(qup, msg); >> + qup_i2c_set_write_mode(qup, msg, run); >> >> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >> - if (ret) >> - goto err; >> + if (!run) { >> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > To run away, or not? > Means, if the controller is not in RUN state, put it in to 'RUN' state. >> + if (ret) >> + goto err; >> + } >> >> writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); >> >> @@ -363,10 +542,13 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> ret = -EIO; >> goto err; >> } >> - } while (qup->pos < msg->len); >> + qup->blk.block_pos++; >> + } while (qup->blk.block_pos < qup->blk.blocks); >> >> /* Wait for the outstanding data in the fifo to drain */ >> - ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE); >> + if (last) >> + ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, >> + ONE_BYTE); >> >> err: >> disable_irq(qup->irq); >> @@ -375,8 +557,17 @@ err: >> return ret; >> } >> >> -static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) >> +static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len, int run) >> { >> + if (qup->use_v2_tags) { >> + len += qup->rx_tag_len; >> + if (run) { >> + len |= QUP_I2C_MX_CONFIG_DURING_RUN; > > Again? It looks like some kind of magic, to trick the controller > that there are more bytes to transfer, or? This means, reconfiguring the _COUNTS when the controller is in 'RUN' state to avoid having 'stop' bit on the bus. > >> + qup->tx_tag_len |= QUP_I2C_MX_CONFIG_DURING_RUN; >> + } >> + writel(qup->tx_tag_len, qup->base + QUP_MX_WRITE_CNT); >> + } >> + >> if (len < qup->in_fifo_sz) { >> /* FIFO mode */ >> writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); >> @@ -389,7 +580,8 @@ static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) >> } >> } >> >> -static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_issue_read_v1(struct qup_i2c_dev *qup, >> + struct i2c_msg *msg) >> { >> u32 addr, len, val; >> >> @@ -402,20 +594,28 @@ static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> writel(val, qup->base + QUP_OUT_FIFO_BASE); >> } >> >> +static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg >> + *msg) >> +{ >> + if (qup->use_v2_tags) >> + qup_i2c_issue_xfer_v2(qup, msg); >> + else >> + qup_i2c_issue_read_v1(qup, msg); >> +} >> >> -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> { >> - u32 opflags; >> u32 val = 0; >> int idx; >> + int len = msg->len + qup->rx_tag_len; > > Is this intentional? > Yes, since i changed the loop around qup_i2c_read_one to count for blocks. Ok, as you say i can change and keep if (use->v2_tags) checks in one place, set the variables accordingly to have better readability. >> >> - for (idx = 0; qup->pos < msg->len; idx++) { >> + for (idx = 0; qup->pos < len; idx++) { >> if ((idx & 1) == 0) { >> /* Check that FIFO have data */ >> - opflags = readl(qup->base + QUP_OPERATIONAL); >> - if (!(opflags & QUP_IN_NOT_EMPTY)) >> + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { > > This should be part of the first patch. ok correct. Will move this below. > >> + dev_err(qup->dev, "timeout for fifo not empty"); >> break; >> - >> + } >> /* Reading 2 words at time */ >> val = readl(qup->base + QUP_IN_FIFO_BASE); >> >> @@ -426,11 +626,50 @@ static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> } >> } >> >> -static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> +static void qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup, >> + struct i2c_msg *msg) >> +{ >> + u32 val; >> + int idx; >> + int pos = 0; >> + /* 2 extra bytes for read tags */ >> + int total = qup->blk.block_data_len[qup->blk.block_pos] + 2; >> + >> + while (pos < total) { >> + /* Check that FIFO have data */ >> + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { >> + dev_err(qup->dev, "timeout for fifo not empty"); >> + break; > > Error not propagated. > ok, will change this. >> + } >> + val = readl(qup->base + QUP_IN_FIFO_BASE); >> + >> + for (idx = 0; idx < 4; idx++, val >>= 8, pos++) { >> + /* first 2 bytes are tag bytes */ >> + if (pos < 2) >> + continue; >> + >> + if (pos >= total) >> + return; >> + >> + msg->buf[qup->pos++] = val & 0xff; >> + } >> + } >> +} >> + >> +static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, >> + struct i2c_msg *msg) >> +{ >> + if (qup->use_v2_tags) >> + qup_i2c_read_fifo_v2(qup, msg); >> + else >> + qup_i2c_read_fifo_v1(qup, msg); >> +} >> + >> +static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, >> + int run, int last) >> { >> unsigned long left; >> int ret; >> - >> /* >> * The QUP block will issue a NACK and STOP on the bus when reaching >> * the end of the read, the length of the read is specified as one byte >> @@ -444,28 +683,34 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> >> qup->msg = msg; >> qup->pos = 0; >> + if (qup->use_v2_tags) >> + qup_i2c_create_tag_v2(qup, msg, last); >> + else >> + qup->blk.blocks = 0; >> >> enable_irq(qup->irq); >> >> - qup_i2c_set_read_mode(qup, msg->len); >> + qup_i2c_set_read_mode(qup, msg->len, run); >> >> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >> - if (ret) >> - goto err; >> + if (!run) { >> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > If !run, place controller in RUN state? > Yes, correct. >> + if (ret) >> + goto err; >> + } >> >> writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); >> >> - ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); >> - if (ret) >> - goto err; >> + do { >> + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); >> + if (ret) >> + goto err; >> >> - qup_i2c_issue_read(qup, msg); >> + qup_i2c_issue_read(qup, msg); >> >> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >> - if (ret) >> - goto err; >> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >> + if (ret) >> + goto err; >> >> - do { >> left = wait_for_completion_timeout(&qup->xfer, HZ); >> if (!left) { >> writel(1, qup->base + QUP_SW_RESET); >> @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >> } >> >> qup_i2c_read_fifo(qup, msg); >> - } while (qup->pos < msg->len); >> + qup->blk.block_pos++; > > This should not be incremented, unless we really have read this block. > We are reading it and only then incrementing it. >> + } while (qup->blk.block_pos < qup->blk.blocks); >> >> err: >> disable_irq(qup->irq); >> @@ -495,7 +741,7 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, >> int num) >> { >> struct qup_i2c_dev *qup = i2c_get_adapdata(adap); >> - int ret, idx; >> + int ret, idx, last; >> >> ret = pm_runtime_get_sync(qup->dev); >> if (ret < 0) >> @@ -507,7 +753,12 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, >> goto out; >> >> /* Configure QUP as I2C mini core */ >> - writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); >> + if (qup->use_v2_tags) { >> + writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG); >> + writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); >> + } else { >> + writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); >> + } >> >> for (idx = 0; idx < num; idx++) { >> if (msgs[idx].len == 0) { >> @@ -520,23 +771,32 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, >> goto out; >> } >> >> + reinit_completion(&qup->xfer); >> + >> + last = (idx == (num - 1)); >> + >> if (msgs[idx].flags & I2C_M_RD) >> - ret = qup_i2c_read_one(qup, &msgs[idx]); >> + ret = qup_i2c_read_one(qup, &msgs[idx], idx, last); >> else >> - ret = qup_i2c_write_one(qup, &msgs[idx]); >> + ret = qup_i2c_write_one(qup, &msgs[idx], idx, last); >> >> if (ret) >> break; >> + } >> >> + if (!ret) >> ret = qup_i2c_change_state(qup, QUP_RESET_STATE); >> - if (ret) >> - break; >> - } >> >> if (ret == 0) >> ret = num; >> out: >> >> + if (qup->use_v2_tags) { >> + kfree(qup->tags); >> + kfree(qup->blk.block_tag_len); >> + kfree(qup->blk.block_data_len); >> + } >> + >> pm_runtime_mark_last_busy(qup->dev); >> pm_runtime_put_autosuspend(qup->dev); >> >> @@ -559,6 +819,14 @@ static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup) >> clk_prepare_enable(qup->pclk); >> } >> >> +static const struct of_device_id qup_i2c_dt_match[] = { >> + { .compatible = "qcom,i2c-qup-v1.1.1"}, >> + { .compatible = "qcom,i2c-qup-v2.1.1"}, >> + { .compatible = "qcom,i2c-qup-v2.2.1"}, > > Space before closing brace, please. > ok, will change. > I am starting to think that it will be more readable > if we just define qup_i2c_algo_v2 and use it, if > controller is v2 and upwards? > As i said will keep all the use_v2 tags check in one place to have better readability. Regards, Sricharan -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Sricharan, On Wed, 2015-04-15 at 12:09 +0530, Sricharan R wrote: > > > +/* frequency definitions for high speed and max speed */ > > > +#define I2C_QUP_CLK_FAST_FREQ 1000000 > > > > This is fast mode, if I am not mistaken. > > > ya, up to 1MHZ is fast and up to 3.4MHZ is HS. > We use this macro to check if the desired freq is in HS range. > The above comment can be changed though to make it clear. My point was that this is neither high nor max speed. > > > + > > > /* Status, Error flags */ > > > #define I2C_STATUS_WR_BUFFER_FULL BIT(0) > > > #define I2C_STATUS_BUS_ACTIVE BIT(8) > > > @@ -102,6 +119,15 @@ > > > #define RESET_BIT 0x0 > > > #define ONE_BYTE 0x1 > > > > > > +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) > > > > Could you explain what is this for? > > > This is a new feature in the V2 version of the controller, > to support multiple i2c sub transfers without having > a 'stop' bit in-between. Without this the i2c controller > inserts a 'stop' on the bus when the WR/RD count registers > reaches zero and are configured for the next transfer. So setting > this bit when the controller is in 'RUN' state, avoids sending the > 'stop' during RUN state. > I can add this comment in the patch. And how v2 of this patch was worked if you introduce this bit now? Bit is also not used by downstream driver, AFICS? > > > > + > > > +struct qup_i2c_block { > > > + int blocks; count > > > + u8 *block_tag_len; just tag_len, > > > + int *block_data_len; just data_len, > > > + int block_pos; just pos? > > > +}; > > > + > > > struct qup_i2c_dev { > > > struct device*dev; > > > void __iomem*base; > > > @@ -115,9 +141,17 @@ struct qup_i2c_dev { > > > int in_fifo_sz; > > > int out_blk_sz; > > > int in_blk_sz; > > > - > > > + struct qup_i2c_blockblk; > > > unsigned longone_byte_t; > > > > > > + int is_hs; > > > + bool use_v2_tags; > > > + > > > + int tx_tag_len; > > > + int rx_tag_len; > > > + u8 *tags; > > > + int tags_pos; > > > + > > > struct i2c_msg*msg; > > > /* Current posion in user message buffer */ > > > int pos; > > > @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, > > > } > > > } > > > > Is this better tag related fields grouping? > > > > > struct qup_i2c_tag_block { > > > > u8 tag[2]; > > // int tag_len; this is alway 2, or? > > int data_len; // this could be zero, right? > > }; > > > There is a struct for qup_i2c_block which has tag and data len. Not sure > what change you suggest above ? Also with V2 transfers tag len need > not be 2. It can be more than that based on the data len. The point is that: I will like to see better grouping of related variables. Now they are spread all over. Would it be possible to also take care for tx_tag_len, rx_tag_len, tags, tags_pos. > > > > -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, > > > + int run) > > > > And 'run' stands for? > 'run' just says whether the controller is in 'RUN' or 'RESET' state. > I can change it to is_run_st to make it clear. > > > { > > > - /* Number of entries to shift out, including the start */ > > > - int total = msg->len + 1; > > > + /* Total Number of entries to shift out, including the tags */ > > > + int total; > > > + > > > + if (qup->use_v2_tags) { > > > + total = msg->len + qup->tx_tag_len; > > > + if (run) > > > + total |= QUP_I2C_MX_CONFIG_DURING_RUN; > > > > What? > > > This means, if the controller is in 'RUN' state, for > reconfiguring the RD/WR counts this bit has to be set to avoid > 'stop' bits. I don't buy it, sorry. Problem with v1 of the tags is that controller can not read more than 256 bytes without automatically generate STOP at the end, because transfer length specified with QUP_TAG_REC tag is 8 bits wide. There is no limitation for writes with v1 tags, because controller is explicitly instructed when to send out STOP. For v2 of the tags, writes behaves more or less the same, and the good news are that there is new read tag QUP_TAG_V2_DATARD, which did't generate STOP when specified amount of data is read, still up to 256 bytes in chunk. Read transfers with size more than 256 could be formed in following way: V2_START | Slave Address | V2_DATARD | countx | ... | V2_DATARD_STOP | county. > > > > > > > -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, > > > + struct i2c_msg *msg, int last) > > > +{ > > > + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); > > > + int len = 0, prev_len = 0; > > > + int blocks = 0; > > > + int rem; > > > + int block_len = 0; > > > + int data_len; > > > + > > > + qup->blk.block_pos = 0; > > > + qup->pos = 0; > > > + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; > > > + rem = msg->len % QUP_READ_LIMIT; > > > + > > > + /* 2 tag bytes for each block + 2 extra bytes for first block */ > > > + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); > > > + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); > > > + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * > > > + qup->blk.blocks, GFP_KERNEL); > > > > Whouldn't be easy to kcalloc struct qup_i2c_tag_block? > > > > > > Allocations could fail and memory is leaking here. > > > ya correct, will change this. Freeing is done at the end of xfer > function, but will have to check for allocation failure. Do you see how memory leak here? > > > > + > > > + while (blocks < qup->blk.blocks) { > > > > > > + blocks++; > > > > Looks like 'for' cycle to me. > > > sorry, not getting it ? This 'while' loop is old plain 'for'. > > > + } > > > + > > > + qup->tx_tag_len = len; > > > + > > > + if (msg->flags & I2C_M_RD) > > > + qup->rx_tag_len = (qup->blk.blocks * 2); This will need some explanation. > > > + > > > +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > +{ > > > + u32 data_len = 0, tag_len; > > > + > > > + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; > > > + > > > + if (!(msg->flags & I2C_M_RD)) > > > + data_len = qup->blk.block_data_len[qup->blk.block_pos]; > > > + > > > + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); > > > > This assumes that writes are up to 256 bytes, and tags and data blocks > > are completely written to FIFO buffer, right? > > > Yes, since we send/read data in blocks (256 bytes). How deep is the FIFO? Is it guaranteed that "the whole" write or read data, including tags will fit in. > > > > > > + > > > +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, > > > + int run, int last) > > > { > > > unsigned long left; > > > int ret; > > > @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > qup->msg = msg; > > > qup->pos = 0; > > > > > > + if (qup->use_v2_tags) > > > + qup_i2c_create_tag_v2(qup, msg, last); > > > + else > > > + qup->blk.blocks = 0; > > > + > > > enable_irq(qup->irq); > > > > > > - qup_i2c_set_write_mode(qup, msg); > > > + qup_i2c_set_write_mode(qup, msg, run); > > > > > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > - if (ret) > > > - goto err; > > > + if (!run) { > > > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > > To run away, or not? > > > Means, if the controller is not in RUN state, put it in to 'RUN' > state. And what is the problem if controller is put in PAUSED state, FIFO filled with data and then RUN again, like in v2 of this patch? <snip> > > > > > > -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > { > > > - u32 opflags; > > > u32 val = 0; > > > int idx; > > > + int len = msg->len + qup->rx_tag_len; > > > > Is this intentional? > > > Yes, since i changed the loop around qup_i2c_read_one to count for > blocks. No, this doesn't make any sense. v1 tags didn't use rx_tag_len, and I don't see how this is related to counting blocks, in this function. <snip> > > > > > > - qup_i2c_issue_read(qup, msg); > > > + qup_i2c_issue_read(qup, msg); > > > > > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > - if (ret) > > > - goto err; > > > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > + if (ret) > > > + goto err; > > > > > > - do { > > > left = wait_for_completion_timeout(&qup->xfer, HZ); > > > if (!left) { > > > writel(1, qup->base + QUP_SW_RESET); > > > @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > } > > > > > > qup_i2c_read_fifo(qup, msg); > > > - } while (qup->pos < msg->len); > > > + qup->blk.block_pos++; > > > > This should not be incremented, unless we really have read this block. > > > We are reading it and only then incrementing it. But read FIFO function could exit because of timeout, which is not checked. The same is true for write operations. Somehow this patch looks overly complex, I don't believe that it should be. Ivan. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Ivan, On 04/15/2015 02:19 PM, Ivan T. Ivanov wrote: > > Hi Sricharan, > > On Wed, 2015-04-15 at 12:09 +0530, Sricharan R wrote: > >>>> +/* frequency definitions for high speed and max speed */ >>>> +#define I2C_QUP_CLK_FAST_FREQ 1000000 >>> >>> This is fast mode, if I am not mistaken. >>> >> ya, up to 1MHZ is fast and up to 3.4MHZ is HS. >> We use this macro to check if the desired freq is in HS range. >> The above comment can be changed though to make it clear. > > My point was that this is neither high nor max speed. > I see that QUP specs defines up to 1MHZ as fast+ speed. >>>> + >>>> /* Status, Error flags */ >>>> #define I2C_STATUS_WR_BUFFER_FULL BIT(0) >>>> #define I2C_STATUS_BUS_ACTIVE BIT(8) >>>> @@ -102,6 +119,15 @@ >>>> #define RESET_BIT 0x0 >>>> #define ONE_BYTE 0x1 >>>> >>>> +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) >>> >>> Could you explain what is this for? >>> >> This is a new feature in the V2 version of the controller, >> to support multiple i2c sub transfers without having >> a 'stop' bit in-between. Without this the i2c controller >> inserts a 'stop' on the bus when the WR/RD count registers >> reaches zero and are configured for the next transfer. So setting >> this bit when the controller is in 'RUN' state, avoids sending the >> 'stop' during RUN state. >> I can add this comment in the patch. > > And how v2 of this patch was worked if you introduce this bit now? > Bit is also not used by downstream driver, AFICS? > The one of the reason for this and the bam support patches in this series was to support multiple transfers of i2c_msgs without a 'stop' inbetween them. So without that the driver sends a 'stop' between each sub-transfer. The v2 of this series supported that only in bam mode and not in non-bam mode. That was a bug. I saw the difference in behavior between bam and non-bam mode while testing with a hdmi adv bridge recently. So added the support in this series. This was neede to bringup the HDMI adv bridge device. I could have added it as a new patch to make it more explicit. >> >>>> + >>>> +struct qup_i2c_block { >>>> + int blocks; > > count > >>>> + u8 *block_tag_len; > > just tag_len, > >>>> + int *block_data_len; > > just data_len, > >>>> + int block_pos; > > just pos? > >>>> +}; >>>> + >>>> struct qup_i2c_dev { >>>> struct device*dev; >>>> void __iomem*base; >>>> @@ -115,9 +141,17 @@ struct qup_i2c_dev { >>>> int in_fifo_sz; >>>> int out_blk_sz; >>>> int in_blk_sz; >>>> - >>>> + struct qup_i2c_blockblk; >>>> unsigned longone_byte_t; >>>> >>>> + int is_hs; >>>> + bool use_v2_tags; >>>> + >>>> + int tx_tag_len; >>>> + int rx_tag_len; >>>> + u8 *tags; >>>> + int tags_pos; >>>> + >>>> struct i2c_msg*msg; >>>> /* Current posion in user message buffer */ >>>> int pos; >>>> @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, >>>> } >>>> } >>> >>> Is this better tag related fields grouping? >>> >> >>> struct qup_i2c_tag_block { >>> >>> u8 tag[2]; >>> // int tag_len; this is alway 2, or? >>> int data_len; // this could be zero, right? >>> }; >>> >> There is a struct for qup_i2c_block which has tag and data len. Not sure >> what change you suggest above ? Also with V2 transfers tag len need >> not be 2. It can be more than that based on the data len. > > The point is that: I will like to see better grouping of > related variables. Now they are spread all over. Would it > be possible to also take care for tx_tag_len, rx_tag_len, > tags, tags_pos. > For this and the above, i will change the groupings and split this patch in to couple of smaller ones. >> >>>> -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>> + int run) >>> >>> And 'run' stands for? >> 'run' just says whether the controller is in 'RUN' or 'RESET' state. >> I can change it to is_run_st to make it clear. >>>> { >>>> - /* Number of entries to shift out, including the start */ >>>> - int total = msg->len + 1; >>>> + /* Total Number of entries to shift out, including the tags */ >>>> + int total; >>>> + >>>> + if (qup->use_v2_tags) { >>>> + total = msg->len + qup->tx_tag_len; >>>> + if (run) >>>> + total |= QUP_I2C_MX_CONFIG_DURING_RUN; >>> >>> What? >>> >> This means, if the controller is in 'RUN' state, for >> reconfiguring the RD/WR counts this bit has to be set to avoid >> 'stop' bits. > > I don't buy it, sorry. Problem with v1 of the tags is that controller > can not read more than 256 bytes without automatically generate STOP > at the end, because transfer length specified with QUP_TAG_REC tag > is 8 bits wide. There is no limitation for writes with v1 tags, > because controller is explicitly instructed when to send out STOP. > correct till this. > For v2 of the tags, writes behaves more or less the same, and the > good news are that there is new read tag QUP_TAG_V2_DATARD, which > did't generate STOP when specified amount of data is read, still > up to 256 bytes in chunk. Read transfers with size more than 256 > could be formed in following way: > > V2_START | Slave Address | V2_DATARD | countx | ... | V2_DATARD_STOP | county. > The above is true for a single subtransfer for reading/writing more than > 256 bytes. But for doing WRITE, READ kind of sub transfers once the first sub transfer (write) is over, and while re-configuring the _COUNT registers for the next transfers, 'a stop' between is inserted. To avoid this , the MX_CONFIG_DURING_RUN bit should be set while in 'RUN' state, before re-configuring for the next sub transfer. The qup spec calls this as bus 'lock-unlock' feature. I tested this and it fixed the wrong data reads in the case of the hdmi adv bridge reads. It was doing 2 i2c_msgs transfers for each i2c_xfer call. The data read was wrong without this patch in v1 mode (default) and even in v2 mode without the lock-unlock even though we do not send a 'STOP' tag command between sub-transfers. >> >>>> >>>> -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, >>>> + struct i2c_msg *msg, int last) >>>> +{ >>>> + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); >>>> + int len = 0, prev_len = 0; >>>> + int blocks = 0; >>>> + int rem; >>>> + int block_len = 0; >>>> + int data_len; >>>> + >>>> + qup->blk.block_pos = 0; >>>> + qup->pos = 0; >>>> + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; >>>> + rem = msg->len % QUP_READ_LIMIT; >>>> + >>>> + /* 2 tag bytes for each block + 2 extra bytes for first block */ >>>> + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); >>>> + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); >>>> + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * >>>> + qup->blk.blocks, GFP_KERNEL); >>> >>> Whouldn't be easy to kcalloc struct qup_i2c_tag_block? >>> >>> >>> Allocations could fail and memory is leaking here. >>> >> ya correct, will change this. Freeing is done at the end of xfer >> function, but will have to check for allocation failure. > > Do you see how memory leak here? if the first allocation pass and second one fails, and i will have to move the kfree calls at the end of i2c_xfer inside the loop. > >> >>>> + >>>> + while (blocks < qup->blk.blocks) { >>>> >>>> + blocks++; >>> >>> Looks like 'for' cycle to me. >>> >> sorry, not getting it ? > > This 'while' loop is old plain 'for'. > ok >>>> + } >>>> + >>>> + qup->tx_tag_len = len; >>>> + >>>> + if (msg->flags & I2C_M_RD) >>>> + qup->rx_tag_len = (qup->blk.blocks * 2); > > This will need some explanation. > ok, will add it. > >>>> + >>>> +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +{ >>>> + u32 data_len = 0, tag_len; >>>> + >>>> + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; >>>> + >>>> + if (!(msg->flags & I2C_M_RD)) >>>> + data_len = qup->blk.block_data_len[qup->blk.block_pos]; >>>> + >>>> + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); >>> >>> This assumes that writes are up to 256 bytes, and tags and data blocks >>> are completely written to FIFO buffer, right? >>> >> Yes, since we send/read data in blocks (256 bytes). > > How deep is the FIFO? Is it guaranteed that "the whole" write > or read data, including tags will fit in. > Write/read fifo functions (also for V1) currently wait for the fifo full and empty flags conditions. This will ensure that the fifo full and empty conditions are taken care before writing and reading. But this can be improved by waiting for block_write/read flags to improve the throughput. >>>> >>>> + >>>> +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>> + int run, int last) >>>> { >>>> unsigned long left; >>>> int ret; >>>> @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> qup->msg = msg; >>>> qup->pos = 0; >>>> >>>> + if (qup->use_v2_tags) >>>> + qup_i2c_create_tag_v2(qup, msg, last); >>>> + else >>>> + qup->blk.blocks = 0; >>>> + >>>> enable_irq(qup->irq); >>>> >>>> - qup_i2c_set_write_mode(qup, msg); >>>> + qup_i2c_set_write_mode(qup, msg, run); >>>> >>>> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> - if (ret) >>>> - goto err; >>>> + if (!run) { >>>> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>> >>> To run away, or not? >>> >> Means, if the controller is not in RUN state, put it in to 'RUN' >> state. > > And what is the problem if controller is put in PAUSED state, FIFO > filled with data and then RUN again, like in v2 of this patch? > This function is not entered with controller in PAUSED state. Only in Reset state (for the first transfer) and Run state for the subsequent sub-transfers. The reason for having this 'run' variable was that while using the lock-unlock feature, the controller should not be put in to run-reset-run state in-between transfers. > <snip> > >>>> >>>> -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> { >>>> - u32 opflags; >>>> u32 val = 0; >>>> int idx; >>>> + int len = msg->len + qup->rx_tag_len; >>> >>> Is this intentional? >>> >> Yes, since i changed the loop around qup_i2c_read_one to count for >> blocks. > > No, this doesn't make any sense. v1 tags didn't use rx_tag_len, and > I don't see how this is related to counting blocks, in this function. > sorry. Did confuse my response last time. This +rx_tag_len is not needed here and infact it is '0' in case of v1. So no effect. > <snip> > >>>> >>>> - qup_i2c_issue_read(qup, msg); >>>> + qup_i2c_issue_read(qup, msg); >>>> >>>> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> - if (ret) >>>> - goto err; >>>> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> + if (ret) >>>> + goto err; >>>> >>>> - do { >>>> left = wait_for_completion_timeout(&qup->xfer, HZ); >>>> if (!left) { >>>> writel(1, qup->base + QUP_SW_RESET); >>>> @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> } >>>> >>>> qup_i2c_read_fifo(qup, msg); >>>> - } while (qup->pos < msg->len); >>>> + qup->blk.block_pos++; >>> >>> This should not be incremented, unless we really have read this block. >>> >> We are reading it and only then incrementing it. > > But read FIFO function could exit because of timeout, which is > not checked. The same is true for write operations. > > Somehow this patch looks overly complex, I don't believe > that it should be. > ok, the read and write fifo timing out error checks should be corrected once i check the error code for qup_i2c_wait_ready function. I will split this patch in to couple of smaller patches and make sure it does not look complex. Regards, Sricharan
Hi Ivan, Sorry resending again, because wrapping seemed to be somehow wrong in my previous response. On 04/15/2015 02:19 PM, Ivan T. Ivanov wrote: > > Hi Sricharan, > > On Wed, 2015-04-15 at 12:09 +0530, Sricharan R wrote: > >>>> +/* frequency definitions for high speed and max speed */ >>>> +#define I2C_QUP_CLK_FAST_FREQ 1000000 >>> >>> This is fast mode, if I am not mistaken. >>> >> ya, up to 1MHZ is fast and up to 3.4MHZ is HS. >> We use this macro to check if the desired freq is in HS range. >> The above comment can be changed though to make it clear. > > My point was that this is neither high nor max speed. > I see that QUP specs defines up to 1MHZ as fast+ speed. >>>> + >>>> /* Status, Error flags */ >>>> #define I2C_STATUS_WR_BUFFER_FULL BIT(0) >>>> #define I2C_STATUS_BUS_ACTIVE BIT(8) >>>> @@ -102,6 +119,15 @@ >>>> #define RESET_BIT 0x0 >>>> #define ONE_BYTE 0x1 >>>> >>>> +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) >>> >>> Could you explain what is this for? >>> >> This is a new feature in the V2 version of the controller, >> to support multiple i2c sub transfers without having >> a 'stop' bit in-between. Without this the i2c controller >> inserts a 'stop' on the bus when the WR/RD count registers >> reaches zero and are configured for the next transfer. So setting >> this bit when the controller is in 'RUN' state, avoids sending the >> 'stop' during RUN state. >> I can add this comment in the patch. > > And how v2 of this patch was worked if you introduce this bit now? > Bit is also not used by downstream driver, AFICS? > The one of the reason for this and the bam support patches in this series was to support multiple transfers of i2c_msgs without a 'stop' inbetween them. So without that the driver sends a 'stop' between each sub-transfer. The v2 of this series supported that only in bam mode and not in non-bam mode. That was a bug. I saw the difference in behavior between bam and non-bam mode while testing with a hdmi adv bridge recently. So added the support in this series. This was neede to bringup the HDMI adv bridge device. I could have added it as a new patch to make it more explicit. >> >>>> + >>>> +struct qup_i2c_block { >>>> + int blocks; > > count > >>>> + u8 *block_tag_len; > > just tag_len, > >>>> + int *block_data_len; > > just data_len, > >>>> + int block_pos; > > just pos? > >>>> +}; >>>> + >>>> struct qup_i2c_dev { >>>> struct device*dev; >>>> void __iomem*base; >>>> @@ -115,9 +141,17 @@ struct qup_i2c_dev { >>>> int in_fifo_sz; >>>> int out_blk_sz; >>>> int in_blk_sz; >>>> - >>>> + struct qup_i2c_blockblk; >>>> unsigned longone_byte_t; >>>> >>>> + int is_hs; >>>> + bool use_v2_tags; >>>> + >>>> + int tx_tag_len; >>>> + int rx_tag_len; >>>> + u8 *tags; >>>> + int tags_pos; >>>> + >>>> struct i2c_msg*msg; >>>> /* Current posion in user message buffer */ >>>> int pos; >>>> @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, >>>> } >>>> } >>> >>> Is this better tag related fields grouping? >>> >> >>> struct qup_i2c_tag_block { >>> >>> u8 tag[2]; >>> // int tag_len; this is alway 2, or? >>> int data_len; // this could be zero, right? >>> }; >>> >> There is a struct for qup_i2c_block which has tag and data len. Not sure >> what change you suggest above ? Also with V2 transfers tag len need >> not be 2. It can be more than that based on the data len. > > The point is that: I will like to see better grouping of > related variables. Now they are spread all over. Would it > be possible to also take care for tx_tag_len, rx_tag_len, > tags, tags_pos. > For this and the above, i will change the groupings and split this patch in to couple of smaller ones. >> >>>> -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>> + int run) >>> >>> And 'run' stands for? >> 'run' just says whether the controller is in 'RUN' or 'RESET' state. >> I can change it to is_run_st to make it clear. >>>> { >>>> - /* Number of entries to shift out, including the start */ >>>> - int total = msg->len + 1; >>>> + /* Total Number of entries to shift out, including the tags */ >>>> + int total; >>>> + >>>> + if (qup->use_v2_tags) { >>>> + total = msg->len + qup->tx_tag_len; >>>> + if (run) >>>> + total |= QUP_I2C_MX_CONFIG_DURING_RUN; >>> >>> What? >>> >> This means, if the controller is in 'RUN' state, for >> reconfiguring the RD/WR counts this bit has to be set to avoid >> 'stop' bits. > > I don't buy it, sorry. Problem with v1 of the tags is that controller > can not read more than 256 bytes without automatically generate STOP > at the end, because transfer length specified with QUP_TAG_REC tag > is 8 bits wide. There is no limitation for writes with v1 tags, > because controller is explicitly instructed when to send out STOP. > correct till this. > For v2 of the tags, writes behaves more or less the same, and the > good news are that there is new read tag QUP_TAG_V2_DATARD, which > did't generate STOP when specified amount of data is read, still > up to 256 bytes in chunk. Read transfers with size more than 256 > could be formed in following way: > > V2_START | Slave Address | V2_DATARD | countx | ... | V2_DATARD_STOP | county. > The above is true for a single subtransfer for reading/writing more than > 256 bytes. But for doing WRITE, READ kind of sub transfers once the first sub transfer (write) is over, and while re-configuring the _COUNT registers for the next transfers, 'a stop' between is inserted. To avoid this,the MX_CONFIG_DURING_RUN bit should be set while in 'RUN' state, before re-configuring for the next sub transfer. The qupspec calls this as bus 'lock-unlock' feature. I tested this and it fixed the wrong data reads in the case of the hdmi adv bridge reads. It was doing 2 i2c_msgs transfers for each i2c_xfer call. The data read was wrong without this patch in v1 mode (default) and even in v2 mode without the lock-unlock even though we do not send a 'STOP' tag command between sub-transfers. >> >>>> >>>> -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, >>>> + struct i2c_msg *msg, int last) >>>> +{ >>>> + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); >>>> + int len = 0, prev_len = 0; >>>> + int blocks = 0; >>>> + int rem; >>>> + int block_len = 0; >>>> + int data_len; >>>> + >>>> + qup->blk.block_pos = 0; >>>> + qup->pos = 0; >>>> + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; >>>> + rem = msg->len % QUP_READ_LIMIT; >>>> + >>>> + /* 2 tag bytes for each block + 2 extra bytes for first block */ >>>> + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); >>>> + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); >>>> + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * >>>> + qup->blk.blocks, GFP_KERNEL); >>> >>> Whouldn't be easy to kcalloc struct qup_i2c_tag_block? >>> >>> >>> Allocations could fail and memory is leaking here. >>> >> ya correct, will change this. Freeing is done at the end of xfer >> function, but will have to check for allocation failure. > > Do you see how memory leak here? > if the first allocation pass and second one fails, and i will have to move the kfree calls at the end of i2c_xfer inside the loop. >> >>>> + >>>> + while (blocks < qup->blk.blocks) { >>>> >>>> + blocks++; >>> >>> Looks like 'for' cycle to me. >>> >> sorry, not getting it ? > > This 'while' loop is old plain 'for'. > ok >>>> + } >>>> + >>>> + qup->tx_tag_len = len; >>>> + >>>> + if (msg->flags & I2C_M_RD) >>>> + qup->rx_tag_len = (qup->blk.blocks * 2); > > This will need some explanation. > ok, will add it. > >>>> + >>>> +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +{ >>>> + u32 data_len = 0, tag_len; >>>> + >>>> + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; >>>> + >>>> + if (!(msg->flags & I2C_M_RD)) >>>> + data_len = qup->blk.block_data_len[qup->blk.block_pos]; >>>> + >>>> + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); >>> >>> This assumes that writes are up to 256 bytes, and tags and data blocks >>> are completely written to FIFO buffer, right? >>> >> Yes, since we send/read data in blocks (256 bytes). > > How deep is the FIFO? Is it guaranteed that "the whole" write > or read data, including tags will fit in. > Write/read fifo functions (also for V1) currently wait for the fifo full and empty flags conditions. This will ensure that the fifo full and empty conditions are taken care before writing and reading. But this can be improved by waiting for block_write/read flags to improve the throughput. >>>> >>>> + >>>> +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>> + int run, int last) >>>> { >>>> unsigned long left; >>>> int ret; >>>> @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> qup->msg = msg; >>>> qup->pos = 0; >>>> >>>> + if (qup->use_v2_tags) >>>> + qup_i2c_create_tag_v2(qup, msg, last); >>>> + else >>>> + qup->blk.blocks = 0; >>>> + >>>> enable_irq(qup->irq); >>>> >>>> - qup_i2c_set_write_mode(qup, msg); >>>> + qup_i2c_set_write_mode(qup, msg, run); >>>> >>>> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> - if (ret) >>>> - goto err; >>>> + if (!run) { >>>> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>> >>> To run away, or not? >>> >> Means, if the controller is not in RUN state, put it in to 'RUN' >> state. > > And what is the problem if controller is put in PAUSED state, FIFO > filled with data and then RUN again, like in v2 of this patch? > This function is not entered with controller in PAUSED state Only in Reset state (for the first transfer) and Run state for the subsequent sub-transfers. The reason for having this 'run' variable was that while using the lock-unlock feature, the controller should not be put in to run-reset-run state in-between transfers. > <snip> > >>>> >>>> -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> { >>>> - u32 opflags; >>>> u32 val = 0; >>>> int idx; >>>> + int len = msg->len + qup->rx_tag_len; >>> >>> Is this intentional? >>> >> Yes, since i changed the loop around qup_i2c_read_one to count for >> blocks. > > No, this doesn't make any sense. v1 tags didn't use rx_tag_len, and > I don't see how this is related to counting blocks, in this function. > sorry. Did confuse my response last time. This +rx_tag_len is not needed here and infact it is '0' in case of v1. So no effect. > <snip> > >>>> >>>> - qup_i2c_issue_read(qup, msg); >>>> + qup_i2c_issue_read(qup, msg); >>>> >>>> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> - if (ret) >>>> - goto err; >>>> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>> + if (ret) >>>> + goto err; >>>> >>>> - do { >>>> left = wait_for_completion_timeout(&qup->xfer, HZ); >>>> if (!left) { >>>> writel(1, qup->base + QUP_SW_RESET); >>>> @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>> } >>>> >>>> qup_i2c_read_fifo(qup, msg); >>>> - } while (qup->pos < msg->len); >>>> + qup->blk.block_pos++; >>> >>> This should not be incremented, unless we really have read this block. >>> >> We are reading it and only then incrementing it. > > But read FIFO function could exit because of timeout, which is > not checked. The same is true for write operations. > > Somehow this patch looks overly complex, I don't believe > that it should be. > > Ivan. > > ok, the read and write fifo timing out error checks should be corrected once i check the error code for qup_i2c_wait_ready function. I will split this patch in to couple of smaller patches and make sure it does not look complex. Regards, Sricharan -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Sricharan, On Wed, 2015-04-15 at 20:14 +0530, Sricharan R wrote: > > > > > > > > > > > +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) > > > > > > > > Could you explain what is this for? > > > > > > > This is a new feature in the V2 version of the controller, > > > to support multiple i2c sub transfers without having > > > a 'stop' bit in-between. Without this the i2c controller > > > inserts a 'stop' on the bus when the WR/RD count registers > > > reaches zero and are configured for the next transfer. So setting > > > this bit when the controller is in 'RUN' state, avoids sending the > > > 'stop' during RUN state. > > > I can add this comment in the patch. > > > > And how v2 of this patch was worked if you introduce this bit now? > > Bit is also not used by downstream driver, AFICS? > > > The one of the reason for this and the bam support patches in > this series was to support multiple transfers of i2c_msgs without > a 'stop' inbetween them. So without that the driver sends a 'stop' > between each sub-transfer. Are you saying that there is bug in the hardware? Please, could you point me to codeaurora driver, which is using this bit? -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > > > +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, > > > > > + int run) > > > > > > > > And 'run' stands for? > > > 'run' just says whether the controller is in 'RUN' or 'RESET' state. > > > I can change it to is_run_st to make it clear. > > > > > { > > > > > - /* Number of entries to shift out, including the start */ > > > > > - int total = msg->len + 1; > > > > > + /* Total Number of entries to shift out, including the tags */ > > > > > + int total; > > > > > + > > > > > + if (qup->use_v2_tags) { > > > > > + total = msg->len + qup->tx_tag_len; > > > > > + if (run) > > > > > + total |= QUP_I2C_MX_CONFIG_DURING_RUN; > > > > > > > > What? > > > > > > > This means, if the controller is in 'RUN' state, for > > > reconfiguring the RD/WR counts this bit has to be set to avoid > > > 'stop' bits. > > > > I don't buy it, sorry. Problem with v1 of the tags is that controller > > can not read more than 256 bytes without automatically generate STOP > > at the end, because transfer length specified with QUP_TAG_REC tag > > is 8 bits wide. There is no limitation for writes with v1 tags, > > because controller is explicitly instructed when to send out STOP. > > > correct till this. > > > For v2 of the tags, writes behaves more or less the same, and the > > good news are that there is new read tag QUP_TAG_V2_DATARD, which > > did't generate STOP when specified amount of data is read, still > > up to 256 bytes in chunk. Read transfers with size more than 256 > > could be formed in following way: > > > > V2_START | Slave Address | V2_DATARD | countx | ... | V2_DATARD_STOP | county. > > > The above is true for a single subtransfer for reading/writing > more than > 256 bytes. But for doing WRITE, READ kind of sub > transfers once the first sub transfer (write) is over, and > while re-configuring the _COUNT registers for the next transfers, > 'a stop' between is inserted. From controller itself or driver? > > > > > +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) > > > > > +{ > > > > > + u32 data_len = 0, tag_len; > > > > > + > > > > > + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; > > > > > + > > > > > + if (!(msg->flags & I2C_M_RD)) > > > > > + data_len = qup->blk.block_data_len[qup->blk.block_pos]; > > > > > + > > > > > + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); > > > > > > > > This assumes that writes are up to 256 bytes, and tags and data blocks > > > > are completely written to FIFO buffer, right? > > > > > > > Yes, since we send/read data in blocks (256 bytes). > > > > How deep is the FIFO? Is it guaranteed that "the whole" write > > or read data, including tags will fit in. > > > Write/read fifo functions (also for V1) currently wait for the > fifo full and empty flags conditions. I will say that this is true for v1, but not for v2, because the way of how FIFO is filled in v2. > > > > > +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, > > > > > + int run, int last) > > > > > { > > > > > unsigned long left; > > > > > int ret; > > > > > @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct > > > > > i2c_msg *msg) > > > > > qup->msg = msg; > > > > > qup->pos = 0; > > > > > > > > > > + if (qup->use_v2_tags) > > > > > + qup_i2c_create_tag_v2(qup, msg, last); > > > > > + else > > > > > + qup->blk.blocks = 0; > > > > > + > > > > > enable_irq(qup->irq); > > > > > > > > > > - qup_i2c_set_write_mode(qup, msg); > > > > > + qup_i2c_set_write_mode(qup, msg, run); > > > > > > > > > > - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > > > - if (ret) > > > > > - goto err; > > > > > + if (!run) { > > > > > + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); > > > > > > > > To run away, or not? > > > > > > > Means, if the controller is not in RUN state, put it in to 'RUN' > > > state. > > > > And what is the problem if controller is put in PAUSED state, FIFO > > filled with data and then RUN again, like in v2 of this patch? > > > This function is not entered with controller in PAUSED state > Only in Reset state (for the first transfer) and Run state for > the subsequent sub-transfers. The reason for having this 'run' > variable was that while using the lock-unlock feature, the > controller should not be put in to run-reset-run state > in-between transfers. Lets see how it will look, when new qup_i2c_write_one_v2 is introduced :-) Ivan -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Ivan, On 04/16/2015 02:06 PM, Ivan T. Ivanov wrote: > > Hi Sricharan, > > On Wed, 2015-04-15 at 20:14 +0530, Sricharan R wrote: >> >>>>>> >>>>>> +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) >>>>> >>>>> Could you explain what is this for? >>>>> >>>> This is a new feature in the V2 version of the controller, >>>> to support multiple i2c sub transfers without having >>>> a 'stop' bit in-between. Without this the i2c controller >>>> inserts a 'stop' on the bus when the WR/RD count registers >>>> reaches zero and are configured for the next transfer. So setting >>>> this bit when the controller is in 'RUN' state, avoids sending the >>>> 'stop' during RUN state. >>>> I can add this comment in the patch. >>> >>> And how v2 of this patch was worked if you introduce this bit now? >>> Bit is also not used by downstream driver, AFICS? >>> >> The one of the reason for this and the bam support patches in >> this series was to support multiple transfers of i2c_msgs without >> a 'stop' inbetween them. So without that the driver sends a 'stop' >> between each sub-transfer. > > Are you saying that there is bug in the hardware? Please, could you > point me to codeaurora driver, which is using this bit? > The controller was not supporting this 'no-stop' feature by default and not sure whether to call it a 'bug' or 'missing feature', which it supports now anyway. Regarding the internal driver, it was trying to coalesce the writes (if they are to same address) by configuring the WR_CNT register to the sum of msg->len of the consecutive sub-transfers. This is no more needed with this 'feature'. > > > -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>>>> +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>>>> + int run) >>>>> >>>>> And 'run' stands for? >>>> 'run' just says whether the controller is in 'RUN' or 'RESET' state. >>>> I can change it to is_run_st to make it clear. >>>>>> { >>>>>> - /* Number of entries to shift out, including the start */ >>>>>> - int total = msg->len + 1; >>>>>> + /* Total Number of entries to shift out, including the tags */ >>>>>> + int total; >>>>>> + >>>>>> + if (qup->use_v2_tags) { >>>>>> + total = msg->len + qup->tx_tag_len; >>>>>> + if (run) >>>>>> + total |= QUP_I2C_MX_CONFIG_DURING_RUN; >>>>> >>>>> What? >>>>> >>>> This means, if the controller is in 'RUN' state, for >>>> reconfiguring the RD/WR counts this bit has to be set to avoid >>>> 'stop' bits. >>> >>> I don't buy it, sorry. Problem with v1 of the tags is that controller >>> can not read more than 256 bytes without automatically generate STOP >>> at the end, because transfer length specified with QUP_TAG_REC tag >>> is 8 bits wide. There is no limitation for writes with v1 tags, >>> because controller is explicitly instructed when to send out STOP. >>> >> correct till this. >> >>> For v2 of the tags, writes behaves more or less the same, and the >>> good news are that there is new read tag QUP_TAG_V2_DATARD, which >>> did't generate STOP when specified amount of data is read, still >>> up to 256 bytes in chunk. Read transfers with size more than 256 >>> could be formed in following way: >>> >>> V2_START | Slave Address | V2_DATARD | countx | ... | V2_DATARD_STOP | county. >>> >> The above is true for a single subtransfer for reading/writing >> more than > 256 bytes. But for doing WRITE, READ kind of sub >> transfers once the first sub transfer (write) is over, and >> while re-configuring the _COUNT registers for the next transfers, >> 'a stop' between is inserted. > > From controller itself or driver? > controller itself. >>>>>> +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) >>>>>> +{ >>>>>> + u32 data_len = 0, tag_len; >>>>>> + >>>>>> + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; >>>>>> + >>>>>> + if (!(msg->flags & I2C_M_RD)) >>>>>> + data_len = qup->blk.block_data_len[qup->blk.block_pos]; >>>>>> + >>>>>> + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); >>>>> >>>>> This assumes that writes are up to 256 bytes, and tags and data blocks >>>>> are completely written to FIFO buffer, right? >>>>> >>>> Yes, since we send/read data in blocks (256 bytes). >>> >>> How deep is the FIFO? Is it guaranteed that "the whole" write >>> or read data, including tags will fit in. >>> >> Write/read fifo functions (also for V1) currently wait for the >> fifo full and empty flags conditions. > > I will say that this is true for v1, but not for v2, > because the way of how FIFO is filled in v2. > fifo is filled using the same 'flags' in both v1 and v2. The difference is the way tags and data are assembled in the output. But as i said, it can be improved atleast in v2 easily (can be done in v1 also, but is not something required in this patch) and i will change that in next version. >>>>>> +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, >>>>>> + int run, int last) >>>>>> { >>>>>> unsigned long left; >>>>>> int ret; >>>>>> @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct >>>>>> i2c_msg *msg) >>>>>> qup->msg = msg; >>>>>> qup->pos = 0; >>>>>> >>>>>> + if (qup->use_v2_tags) >>>>>> + qup_i2c_create_tag_v2(qup, msg, last); >>>>>> + else >>>>>> + qup->blk.blocks = 0; >>>>>> + >>>>>> enable_irq(qup->irq); >>>>>> >>>>>> - qup_i2c_set_write_mode(qup, msg); >>>>>> + qup_i2c_set_write_mode(qup, msg, run); >>>>>> >>>>>> - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>>>> - if (ret) >>>>>> - goto err; >>>>>> + if (!run) { >>>>>> + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); >>>>> >>>>> To run away, or not? >>>>> >>>> Means, if the controller is not in RUN state, put it in to 'RUN' >>>> state. >>> >>> And what is the problem if controller is put in PAUSED state, FIFO >>> filled with data and then RUN again, like in v2 of this patch? >>> >> This function is not entered with controller in PAUSED state >> Only in Reset state (for the first transfer) and Run state for >> the subsequent sub-transfers. The reason for having this 'run' >> variable was that while using the lock-unlock feature, the >> controller should not be put in to run-reset-run state >> in-between transfers. > > Lets see how it will look, when new qup_i2c_write_one_v2 is introduced :-) > ok. Regards, Sricharan
diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c index 9ccf3e8..16a8f69 100644 --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -24,6 +24,7 @@ #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/slab.h> /* QUP Registers */ #define QUP_CONFIG 0x000 @@ -42,6 +43,7 @@ #define QUP_IN_FIFO_BASE 0x218 #define QUP_I2C_CLK_CTL 0x400 #define QUP_I2C_STATUS 0x404 +#define QUP_I2C_MASTER_GEN 0x408 /* QUP States and reset values */ #define QUP_RESET_STATE 0 @@ -69,6 +71,8 @@ #define QUP_CLOCK_AUTO_GATE BIT(13) #define I2C_MINI_CORE (2 << 8) #define I2C_N_VAL 15 +#define I2C_N_VAL_V2 7 + /* Most significant word offset in FIFO port */ #define QUP_MSW_SHIFT (I2C_N_VAL + 1) @@ -80,17 +84,30 @@ #define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN) +#define QUP_V2_TAGS_EN 1 + #define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03) #define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07) #define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03) #define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07) -/* QUP tags */ +/* QUP V1 tags */ #define QUP_TAG_START (1 << 8) #define QUP_TAG_DATA (2 << 8) #define QUP_TAG_STOP (3 << 8) #define QUP_TAG_REC (4 << 8) +/* QUP v2 tags */ +#define QUP_TAG_V2_HS 0xff +#define QUP_TAG_V2_START 0x81 +#define QUP_TAG_V2_DATAWR 0x82 +#define QUP_TAG_V2_DATAWR_STOP 0x83 +#define QUP_TAG_V2_DATARD 0x85 +#define QUP_TAG_V2_DATARD_STOP 0x87 + +/* frequency definitions for high speed and max speed */ +#define I2C_QUP_CLK_FAST_FREQ 1000000 + /* Status, Error flags */ #define I2C_STATUS_WR_BUFFER_FULL BIT(0) #define I2C_STATUS_BUS_ACTIVE BIT(8) @@ -102,6 +119,15 @@ #define RESET_BIT 0x0 #define ONE_BYTE 0x1 +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) + +struct qup_i2c_block { + int blocks; + u8 *block_tag_len; + int *block_data_len; + int block_pos; +}; + struct qup_i2c_dev { struct device *dev; void __iomem *base; @@ -115,9 +141,17 @@ struct qup_i2c_dev { int in_fifo_sz; int out_blk_sz; int in_blk_sz; - + struct qup_i2c_block blk; unsigned long one_byte_t; + int is_hs; + bool use_v2_tags; + + int tx_tag_len; + int rx_tag_len; + u8 *tags; + int tags_pos; + struct i2c_msg *msg; /* Current posion in user message buffer */ int pos; @@ -263,10 +297,19 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, } } -static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg, + int run) { - /* Number of entries to shift out, including the start */ - int total = msg->len + 1; + /* Total Number of entries to shift out, including the tags */ + int total; + + if (qup->use_v2_tags) { + total = msg->len + qup->tx_tag_len; + if (run) + total |= QUP_I2C_MX_CONFIG_DURING_RUN; + } else { + total = msg->len + 1; /* plus start tag */ + } if (total < qup->out_fifo_sz) { /* FIFO mode */ @@ -280,7 +323,7 @@ static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) } } -static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_issue_write_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) { u32 addr = msg->addr << 1; u32 qup_tag; @@ -321,7 +364,136 @@ static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) } } -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_create_tag_v2(struct qup_i2c_dev *qup, + struct i2c_msg *msg, int last) +{ + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); + int len = 0, prev_len = 0; + int blocks = 0; + int rem; + int block_len = 0; + int data_len; + + qup->blk.block_pos = 0; + qup->pos = 0; + qup->blk.blocks = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT; + rem = msg->len % QUP_READ_LIMIT; + + /* 2 tag bytes for each block + 2 extra bytes for first block */ + qup->tags = kzalloc((qup->blk.blocks * 2) + 2, GFP_KERNEL); + qup->blk.block_tag_len = kzalloc(qup->blk.blocks, GFP_KERNEL); + qup->blk.block_data_len = kzalloc(sizeof(*qup->blk.block_data_len) * + qup->blk.blocks, GFP_KERNEL); + + while (blocks < qup->blk.blocks) { + /* 0 is used to specify a READ_LIMIT of 256 bytes */ + data_len = (blocks < (qup->blk.blocks - 1)) ? 0 : rem; + + /* Send START and ADDR bytes only for the first block */ + if (!blocks) { + qup->tags[len++] = QUP_TAG_V2_START; + + if (qup->is_hs) { + qup->tags[len++] = QUP_TAG_V2_HS; + qup->tags[len++] = QUP_TAG_V2_START; + } + + qup->tags[len++] = addr & 0xff; + if (msg->flags & I2C_M_TEN) + qup->tags[len++] = addr >> 8; + } + + /* Send _STOP commands for the last block */ + if ((blocks == (qup->blk.blocks - 1)) && last) { + if (msg->flags & I2C_M_RD) + qup->tags[len++] = QUP_TAG_V2_DATARD_STOP; + else + qup->tags[len++] = QUP_TAG_V2_DATAWR_STOP; + } else { + if (msg->flags & I2C_M_RD) + qup->tags[len++] = QUP_TAG_V2_DATARD; + else + qup->tags[len++] = QUP_TAG_V2_DATAWR; + } + + qup->tags[len++] = data_len; + block_len = len - prev_len; + prev_len = len; + qup->blk.block_tag_len[blocks] = block_len; + + if (!data_len) + qup->blk.block_data_len[blocks] = QUP_READ_LIMIT; + else + qup->blk.block_data_len[blocks] = data_len; + + qup->tags_pos = 0; + blocks++; + } + + qup->tx_tag_len = len; + + if (msg->flags & I2C_M_RD) + qup->rx_tag_len = (qup->blk.blocks * 2); + else + qup->rx_tag_len = 0; +} + +static u32 qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf, + int dlen, u8 *dbuf) +{ + u32 val = 0, idx = 0, pos = 0, i = 0, t; + int len = tlen + dlen; + u8 *buf = tbuf; + + while (len > 0) { + if (qup_i2c_wait_ready(qup, QUP_OUT_FULL, 0, 4)) { + dev_err(qup->dev, "timeout for fifo out full"); + break; + } + + t = (len >= 4) ? 4 : len; + + while (idx < t) { + if (!i && (pos >= tlen)) { + buf = dbuf; + pos = 0; + i = 1; + } + val |= buf[pos++] << (idx++ * 8); + } + + writel(val, qup->base + QUP_OUT_FIFO_BASE); + idx = 0; + val = 0; + len -= 4; + } + + return 0; +} + +static void qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg) +{ + u32 data_len = 0, tag_len; + + tag_len = qup->blk.block_tag_len[qup->blk.block_pos]; + + if (!(msg->flags & I2C_M_RD)) + data_len = qup->blk.block_data_len[qup->blk.block_pos]; + + qup_i2c_send_data(qup, tag_len, qup->tags, data_len, msg->buf); +} + +static void qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg + *msg) +{ + if (qup->use_v2_tags) + qup_i2c_issue_xfer_v2(qup, msg); + else + qup_i2c_issue_write_v1(qup, msg); +} + +static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, + int run, int last) { unsigned long left; int ret; @@ -329,13 +501,20 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) qup->msg = msg; qup->pos = 0; + if (qup->use_v2_tags) + qup_i2c_create_tag_v2(qup, msg, last); + else + qup->blk.blocks = 0; + enable_irq(qup->irq); - qup_i2c_set_write_mode(qup, msg); + qup_i2c_set_write_mode(qup, msg, run); - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); - if (ret) - goto err; + if (!run) { + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto err; + } writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); @@ -363,10 +542,13 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) ret = -EIO; goto err; } - } while (qup->pos < msg->len); + qup->blk.block_pos++; + } while (qup->blk.block_pos < qup->blk.blocks); /* Wait for the outstanding data in the fifo to drain */ - ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE); + if (last) + ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, + ONE_BYTE); err: disable_irq(qup->irq); @@ -375,8 +557,17 @@ err: return ret; } -static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) +static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len, int run) { + if (qup->use_v2_tags) { + len += qup->rx_tag_len; + if (run) { + len |= QUP_I2C_MX_CONFIG_DURING_RUN; + qup->tx_tag_len |= QUP_I2C_MX_CONFIG_DURING_RUN; + } + writel(qup->tx_tag_len, qup->base + QUP_MX_WRITE_CNT); + } + if (len < qup->in_fifo_sz) { /* FIFO mode */ writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); @@ -389,7 +580,8 @@ static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) } } -static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_issue_read_v1(struct qup_i2c_dev *qup, + struct i2c_msg *msg) { u32 addr, len, val; @@ -402,20 +594,28 @@ static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) writel(val, qup->base + QUP_OUT_FIFO_BASE); } +static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg + *msg) +{ + if (qup->use_v2_tags) + qup_i2c_issue_xfer_v2(qup, msg); + else + qup_i2c_issue_read_v1(qup, msg); +} -static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_read_fifo_v1(struct qup_i2c_dev *qup, struct i2c_msg *msg) { - u32 opflags; u32 val = 0; int idx; + int len = msg->len + qup->rx_tag_len; - for (idx = 0; qup->pos < msg->len; idx++) { + for (idx = 0; qup->pos < len; idx++) { if ((idx & 1) == 0) { /* Check that FIFO have data */ - opflags = readl(qup->base + QUP_OPERATIONAL); - if (!(opflags & QUP_IN_NOT_EMPTY)) + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { + dev_err(qup->dev, "timeout for fifo not empty"); break; - + } /* Reading 2 words at time */ val = readl(qup->base + QUP_IN_FIFO_BASE); @@ -426,11 +626,50 @@ static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) } } -static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) +static void qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + u32 val; + int idx; + int pos = 0; + /* 2 extra bytes for read tags */ + int total = qup->blk.block_data_len[qup->blk.block_pos] + 2; + + while (pos < total) { + /* Check that FIFO have data */ + if (qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, 1, 4)) { + dev_err(qup->dev, "timeout for fifo not empty"); + break; + } + val = readl(qup->base + QUP_IN_FIFO_BASE); + + for (idx = 0; idx < 4; idx++, val >>= 8, pos++) { + /* first 2 bytes are tag bytes */ + if (pos < 2) + continue; + + if (pos >= total) + return; + + msg->buf[qup->pos++] = val & 0xff; + } + } +} + +static void qup_i2c_read_fifo(struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + if (qup->use_v2_tags) + qup_i2c_read_fifo_v2(qup, msg); + else + qup_i2c_read_fifo_v1(qup, msg); +} + +static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg, + int run, int last) { unsigned long left; int ret; - /* * The QUP block will issue a NACK and STOP on the bus when reaching * the end of the read, the length of the read is specified as one byte @@ -444,28 +683,34 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) qup->msg = msg; qup->pos = 0; + if (qup->use_v2_tags) + qup_i2c_create_tag_v2(qup, msg, last); + else + qup->blk.blocks = 0; enable_irq(qup->irq); - qup_i2c_set_read_mode(qup, msg->len); + qup_i2c_set_read_mode(qup, msg->len, run); - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); - if (ret) - goto err; + if (!run) { + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto err; + } writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); - ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); - if (ret) - goto err; + do { + ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); + if (ret) + goto err; - qup_i2c_issue_read(qup, msg); + qup_i2c_issue_read(qup, msg); - ret = qup_i2c_change_state(qup, QUP_RUN_STATE); - if (ret) - goto err; + ret = qup_i2c_change_state(qup, QUP_RUN_STATE); + if (ret) + goto err; - do { left = wait_for_completion_timeout(&qup->xfer, HZ); if (!left) { writel(1, qup->base + QUP_SW_RESET); @@ -481,7 +726,8 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) } qup_i2c_read_fifo(qup, msg); - } while (qup->pos < msg->len); + qup->blk.block_pos++; + } while (qup->blk.block_pos < qup->blk.blocks); err: disable_irq(qup->irq); @@ -495,7 +741,7 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, int num) { struct qup_i2c_dev *qup = i2c_get_adapdata(adap); - int ret, idx; + int ret, idx, last; ret = pm_runtime_get_sync(qup->dev); if (ret < 0) @@ -507,7 +753,12 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, goto out; /* Configure QUP as I2C mini core */ - writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); + if (qup->use_v2_tags) { + writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG); + writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN); + } else { + writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG); + } for (idx = 0; idx < num; idx++) { if (msgs[idx].len == 0) { @@ -520,23 +771,32 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, goto out; } + reinit_completion(&qup->xfer); + + last = (idx == (num - 1)); + if (msgs[idx].flags & I2C_M_RD) - ret = qup_i2c_read_one(qup, &msgs[idx]); + ret = qup_i2c_read_one(qup, &msgs[idx], idx, last); else - ret = qup_i2c_write_one(qup, &msgs[idx]); + ret = qup_i2c_write_one(qup, &msgs[idx], idx, last); if (ret) break; + } + if (!ret) ret = qup_i2c_change_state(qup, QUP_RESET_STATE); - if (ret) - break; - } if (ret == 0) ret = num; out: + if (qup->use_v2_tags) { + kfree(qup->tags); + kfree(qup->blk.block_tag_len); + kfree(qup->blk.block_data_len); + } + pm_runtime_mark_last_busy(qup->dev); pm_runtime_put_autosuspend(qup->dev); @@ -559,6 +819,14 @@ static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup) clk_prepare_enable(qup->pclk); } +static const struct of_device_id qup_i2c_dt_match[] = { + { .compatible = "qcom,i2c-qup-v1.1.1"}, + { .compatible = "qcom,i2c-qup-v2.1.1"}, + { .compatible = "qcom,i2c-qup-v2.2.1"}, + {} +}; +MODULE_DEVICE_TABLE(of, qup_i2c_dt_match); + static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup) { u32 config; @@ -580,8 +848,9 @@ static int qup_i2c_probe(struct platform_device *pdev) struct resource *res; u32 io_mode, hw_ver, size; int ret, fs_div, hs_div; - int src_clk_freq; + int src_clk_freq, clk_freq_max; u32 clk_freq = 100000; + const struct of_device_id *of_id; qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL); if (!qup) @@ -593,8 +862,19 @@ static int qup_i2c_probe(struct platform_device *pdev) of_property_read_u32(node, "clock-frequency", &clk_freq); - /* We support frequencies up to FAST Mode (400KHz) */ - if (!clk_freq || clk_freq > 400000) { + of_id = of_match_node(qup_i2c_dt_match, node); + + if (of_device_is_compatible(pdev->dev.of_node, + "qcom,i2c-qup-v1.1.1")) { + qup->use_v2_tags = 0; + clk_freq_max = 400000; + } else { + qup->use_v2_tags = 1; + clk_freq_max = 3400000; + } + + /* We support frequencies up to HIGH SPEED Mode (3400KHz) */ + if (!clk_freq || clk_freq > clk_freq_max) { dev_err(qup->dev, "clock frequency not supported %d\n", clk_freq); return -EINVAL; @@ -672,8 +952,17 @@ static int qup_i2c_probe(struct platform_device *pdev) qup->in_fifo_sz = qup->in_blk_sz * (2 << size); src_clk_freq = clk_get_rate(qup->clk); - fs_div = ((src_clk_freq / clk_freq) / 2) - 3; - hs_div = 3; + if (clk_freq > I2C_QUP_CLK_FAST_FREQ) { + fs_div = I2C_QUP_CLK_FAST_FREQ; + hs_div = (src_clk_freq / clk_freq) / 3; + + qup->is_hs = 1; + } else { + fs_div = ((src_clk_freq / clk_freq) / 2) - 3; + hs_div = 3; + } + + hs_div = min_t(int, hs_div, 0x7); qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff); /* @@ -770,14 +1059,6 @@ static const struct dev_pm_ops qup_i2c_qup_pm_ops = { NULL) }; -static const struct of_device_id qup_i2c_dt_match[] = { - { .compatible = "qcom,i2c-qup-v1.1.1" }, - { .compatible = "qcom,i2c-qup-v2.1.1" }, - { .compatible = "qcom,i2c-qup-v2.2.1" }, - {} -}; -MODULE_DEVICE_TABLE(of, qup_i2c_dt_match); - static struct platform_driver qup_i2c_driver = { .probe = qup_i2c_probe, .remove = qup_i2c_remove,