@@ -26,6 +26,15 @@ Required properties:
"cal" - reference clock for RCLK delay calibration (optional)
"sleep" - sleep clock for RCLK delay calibration (optional)
+Optional Properties:
+- qcom,devfreq,freq-table - specifies supported frequencies for clock scaling.
+ Clock scaling logic shall toggle between these frequencies based
+ on card load. In case the defined frequencies are over or below
+ the supported card frequencies, they will be overridden
+ during card init. In case this entry is not supplied,
+ the driver will construct one based on the card
+ supported max and min frequencies.
+ The frequencies must be ordered from lowest to highest.
Example:
sdhc_1: sdhci@f9824900 {
@@ -43,6 +52,7 @@ Example:
clocks = <&gcc GCC_SDCC1_APPS_CLK>, <&gcc GCC_SDCC1_AHB_CLK>;
clock-names = "core", "iface";
+ qcom,devfreq,freq-table = <52000000 200000000>;
};
sdhc_2: sdhci@f98a4900 {
@@ -14,6 +14,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
+#include <linux/devfreq.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/pagemap.h>
@@ -112,6 +113,552 @@ static inline void mmc_should_fail_request(struct mmc_host *host,
#endif /* CONFIG_FAIL_MMC_REQUEST */
+static bool mmc_is_data_request(struct mmc_request *mmc_request)
+{
+ switch (mmc_request->cmd->opcode) {
+ case MMC_READ_SINGLE_BLOCK:
+ case MMC_READ_MULTIPLE_BLOCK:
+ case MMC_WRITE_BLOCK:
+ case MMC_WRITE_MULTIPLE_BLOCK:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static void mmc_clk_scaling_start_busy(struct mmc_host *host, bool lock_needed)
+{
+ struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling;
+
+ if (!clk_scaling->enable)
+ return;
+
+ if (lock_needed)
+ spin_lock_bh(&clk_scaling->lock);
+
+ clk_scaling->start_busy = ktime_get();
+ clk_scaling->is_busy_started = true;
+
+ if (lock_needed)
+ spin_unlock_bh(&clk_scaling->lock);
+}
+
+static void mmc_clk_scaling_stop_busy(struct mmc_host *host, bool lock_needed)
+{
+ struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling;
+
+ if (!clk_scaling->enable)
+ return;
+
+ if (lock_needed)
+ spin_lock_bh(&clk_scaling->lock);
+
+ if (!clk_scaling->is_busy_started) {
+ WARN_ON(1);
+ goto out;
+ }
+
+ clk_scaling->total_busy_time_us +=
+ ktime_to_us(ktime_sub(ktime_get(),
+ clk_scaling->start_busy));
+ pr_debug("%s: accumulated busy time is %lu usec\n",
+ mmc_hostname(host), clk_scaling->total_busy_time_us);
+ clk_scaling->is_busy_started = false;
+
+out:
+ if (lock_needed)
+ spin_unlock_bh(&clk_scaling->lock);
+}
+
+/**
+ * mmc_can_scale_clk() - Check clock scaling capability
+ * @host: pointer to mmc host structure
+ */
+bool mmc_can_scale_clk(struct mmc_host *host)
+{
+ if (!host) {
+ pr_err("bad host parameter\n");
+ WARN_ON(1);
+ return false;
+ }
+
+ return host->caps2 & MMC_CAP2_CLK_SCALE;
+}
+EXPORT_SYMBOL(mmc_can_scale_clk);
+
+static int mmc_devfreq_get_dev_status(struct device *dev,
+ struct devfreq_dev_status *status)
+{
+ struct mmc_host *host = container_of(dev, struct mmc_host, class_dev);
+ struct mmc_devfeq_clk_scaling *clk_scaling;
+
+ if (!host) {
+ pr_err("bad host parameter\n");
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ clk_scaling = &host->clk_scaling;
+
+ if (!clk_scaling->enable)
+ return 0;
+
+ spin_lock_bh(&clk_scaling->lock);
+
+ /* accumulate the busy time of ongoing work */
+ memset(status, 0, sizeof(*status));
+ if (clk_scaling->is_busy_started) {
+ mmc_clk_scaling_stop_busy(host, false);
+ mmc_clk_scaling_start_busy(host, false);
+ }
+
+ status->busy_time = clk_scaling->total_busy_time_us;
+ status->total_time = ktime_to_us(ktime_sub(ktime_get(),
+ clk_scaling->measure_interval_start));
+ clk_scaling->total_busy_time_us = 0;
+ status->current_frequency = clk_scaling->curr_freq;
+ clk_scaling->measure_interval_start = ktime_get();
+
+ pr_debug("%s: status: load = %lu%% - total_time=%lu busy_time = %lu, clk=%lu\n",
+ mmc_hostname(host),
+ (status->busy_time*100)/status->total_time,
+ status->total_time, status->busy_time,
+ status->current_frequency);
+
+ spin_unlock_bh(&clk_scaling->lock);
+
+ return 0;
+}
+
+static bool mmc_is_valid_state_for_clk_scaling(struct mmc_host *host)
+{
+ struct mmc_card *card = host->card;
+ u32 status;
+
+ /*
+ * If the current partition type is RPMB, clock switching may not
+ * work properly as sending tuning command (CMD21) is illegal in
+ * this mode.
+ */
+ if (!card || (mmc_card_mmc(card) &&
+ (card->part_curr == EXT_CSD_PART_CONFIG_ACC_RPMB ||
+ mmc_card_doing_bkops(card))))
+ return false;
+
+ if (mmc_send_status(card, &status)) {
+ pr_err("%s: Get card status fail\n", mmc_hostname(card->host));
+ return false;
+ }
+
+ return R1_CURRENT_STATE(status) == R1_STATE_TRAN;
+}
+
+int mmc_clk_update_freq(struct mmc_host *host,
+ unsigned long freq, enum mmc_load state)
+{
+ int err = 0;
+
+ if (!host) {
+ pr_err("bad host parameter\n");
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ /* make sure the card supports the frequency we want */
+ if (unlikely(freq > host->card->clk_scaling_highest)) {
+ freq = host->card->clk_scaling_highest;
+ pr_warn("%s: %s: frequency was overridden to %lu\n",
+ mmc_hostname(host), __func__,
+ host->card->clk_scaling_highest);
+ }
+
+ if (unlikely(freq < host->card->clk_scaling_lowest)) {
+ freq = host->card->clk_scaling_lowest;
+ pr_warn("%s: %s: frequency was overridden to %lu\n",
+ mmc_hostname(host), __func__,
+ host->card->clk_scaling_lowest);
+ }
+
+ if (freq == host->clk_scaling.curr_freq)
+ goto out;
+
+ if (host->ops->notify_load) {
+ err = host->ops->notify_load(host, state);
+ if (err) {
+ pr_err("%s: %s: fail on notify_load\n",
+ mmc_hostname(host), __func__);
+ goto out;
+ }
+ }
+
+ if (!mmc_is_valid_state_for_clk_scaling(host)) {
+ pr_debug("%s: invalid state for clock scaling - skipping",
+ mmc_hostname(host));
+ goto invalid_state;
+ }
+
+ err = host->bus_ops->change_bus_speed(host, &freq);
+ if (!err)
+ host->clk_scaling.curr_freq = freq;
+ else
+ pr_err("%s: %s: failed (%d) at freq=%lu\n",
+ mmc_hostname(host), __func__, err, freq);
+
+invalid_state:
+ if (err) {
+ /* restore previous state */
+ if (host->ops->notify_load)
+ if (host->ops->notify_load(host,
+ host->clk_scaling.state))
+ pr_err("%s: %s: fail on notify_load restore\n",
+ mmc_hostname(host), __func__);
+ }
+out:
+ return err;
+}
+EXPORT_SYMBOL(mmc_clk_update_freq);
+
+static int mmc_devfreq_set_target(struct device *dev,
+ unsigned long *freq, u32 devfreq_flags)
+{
+ struct mmc_host *host = container_of(dev, struct mmc_host, class_dev);
+ struct mmc_devfeq_clk_scaling *clk_scaling;
+ int err = 0;
+ int abort;
+ unsigned long pflags = current->flags;
+
+ /* Ensure scaling would happen even in memory pressure conditions */
+ current->flags |= PF_MEMALLOC;
+
+ if (!(host && freq)) {
+ pr_err("%s: unexpected host/freq parameter\n", __func__);
+ err = -EINVAL;
+ goto out;
+ }
+
+ clk_scaling = &host->clk_scaling;
+
+ if (!clk_scaling->enable)
+ goto out;
+
+ pr_debug("%s: target freq = %lu (%s)\n", mmc_hostname(host),
+ *freq, current->comm);
+
+ /* No need to scale the clocks if they are gated */
+ if (!host->ios.clock)
+ goto out;
+
+ spin_lock_bh(&clk_scaling->lock);
+ if (clk_scaling->target_freq == *freq ||
+ clk_scaling->skip_clk_scale_freq_update ||
+ clk_scaling->clk_scaling_in_progress) {
+ spin_unlock_bh(&clk_scaling->lock);
+ goto out;
+ }
+ clk_scaling->need_freq_change = true;
+ clk_scaling->target_freq = *freq;
+ clk_scaling->state = *freq < clk_scaling->curr_freq ?
+ MMC_LOAD_LOW : MMC_LOAD_HIGH;
+ spin_unlock_bh(&clk_scaling->lock);
+
+ abort = __mmc_claim_host(host, NULL, &clk_scaling->devfreq_abort);
+ if (abort)
+ goto out;
+
+ /*
+ * In case we were able to claim host there is no need to
+ * defer the frequency change. It will be done now
+ */
+ clk_scaling->need_freq_change = false;
+
+ err = mmc_clk_update_freq(host, *freq, clk_scaling->state);
+ if (err && err != -EAGAIN) {
+ pr_err("%s: clock scale to %lu failed with error %d\n",
+ mmc_hostname(host), *freq, err);
+ } else {
+ pr_debug("%s: clock change to %lu finished successfully (%s)\n",
+ mmc_hostname(host), *freq, current->comm);
+ }
+
+ mmc_release_host(host);
+out:
+ current->flags &= ~PF_MEMALLOC;
+ current->flags |= pflags & PF_MEMALLOC;
+ return err;
+}
+
+/**
+ * mmc_deferred_scaling() - scale clocks from data path (mmc thread context)
+ * @host: pointer to mmc host structure
+ *
+ * This function does clock scaling in case "need_freq_change" flag was set
+ * by the clock scaling logic.
+ */
+void mmc_deferred_scaling(struct mmc_host *host)
+{
+ unsigned long target_freq;
+ int err;
+
+ if (!host->clk_scaling.enable)
+ return;
+
+ spin_lock_bh(&host->clk_scaling.lock);
+
+ if (host->clk_scaling.clk_scaling_in_progress ||
+ !(host->clk_scaling.need_freq_change)) {
+ spin_unlock_bh(&host->clk_scaling.lock);
+ return;
+ }
+
+
+ atomic_inc(&host->clk_scaling.devfreq_abort);
+ target_freq = host->clk_scaling.target_freq;
+ host->clk_scaling.clk_scaling_in_progress = true;
+ host->clk_scaling.need_freq_change = false;
+ spin_unlock_bh(&host->clk_scaling.lock);
+ pr_debug("%s: doing deferred frequency change (%lu) (%s)\n",
+ mmc_hostname(host),
+ target_freq, current->comm);
+
+ err = mmc_clk_update_freq(host, target_freq,
+ host->clk_scaling.state);
+ if (err && err != -EAGAIN) {
+ pr_err("%s: failed on deferred scale clocks (%d)\n",
+ mmc_hostname(host), err);
+ } else {
+ pr_debug("%s: clocks were successfully scaled to %lu (%s)\n",
+ mmc_hostname(host),
+ target_freq, current->comm);
+ }
+ host->clk_scaling.clk_scaling_in_progress = false;
+ atomic_dec(&host->clk_scaling.devfreq_abort);
+}
+EXPORT_SYMBOL(mmc_deferred_scaling);
+
+static int mmc_devfreq_create_freq_table(struct mmc_host *host)
+{
+ int i;
+ struct mmc_devfeq_clk_scaling *clk_scaling = &host->clk_scaling;
+
+ pr_debug("%s: supported: lowest=%lu, highest=%lu\n",
+ mmc_hostname(host),
+ host->card->clk_scaling_lowest,
+ host->card->clk_scaling_highest);
+
+ /*
+ * Create the frequency table and initialize it with default values.
+ * Initialize it with platform specific frequencies if the frequency
+ * table supplied by platform driver is present, otherwise initialize
+ * it with min and max frequencies supported by the card.
+ */
+ if (!clk_scaling->freq_table) {
+ if (clk_scaling->pltfm_freq_table_sz)
+ clk_scaling->freq_table_sz =
+ clk_scaling->pltfm_freq_table_sz;
+ else
+ clk_scaling->freq_table_sz = 2;
+
+ clk_scaling->freq_table = kzalloc(
+ (clk_scaling->freq_table_sz *
+ sizeof(*(clk_scaling->freq_table))), GFP_KERNEL);
+ if (!clk_scaling->freq_table)
+ return -ENOMEM;
+
+ if (clk_scaling->pltfm_freq_table) {
+ memcpy(clk_scaling->freq_table,
+ clk_scaling->pltfm_freq_table,
+ (clk_scaling->pltfm_freq_table_sz *
+ sizeof(*(clk_scaling->pltfm_freq_table))));
+ } else {
+ pr_debug("%s: no frequency table defined - setting default\n",
+ mmc_hostname(host));
+ clk_scaling->freq_table[0] =
+ host->card->clk_scaling_lowest;
+ clk_scaling->freq_table[1] =
+ host->card->clk_scaling_highest;
+ goto out;
+ }
+ }
+
+ if (host->card->clk_scaling_lowest >
+ clk_scaling->freq_table[0])
+ pr_debug("%s: frequency table undershot possible freq\n",
+ mmc_hostname(host));
+
+ for (i = 0; i < clk_scaling->freq_table_sz; i++) {
+ if (clk_scaling->freq_table[i] <=
+ host->card->clk_scaling_highest)
+ continue;
+ clk_scaling->freq_table[i] =
+ host->card->clk_scaling_highest;
+ clk_scaling->freq_table_sz = i + 1;
+ pr_debug("%s: frequency table overshot possible freq (%d)\n",
+ mmc_hostname(host), clk_scaling->freq_table[i]);
+ break;
+ }
+
+out:
+ /**
+ * devfreq requires unsigned long type freq_table while the
+ * freq_table in clk_scaling is un32. Here allocates an individual
+ * memory space for it and release it when exit clock scaling.
+ */
+ clk_scaling->devfreq_profile.freq_table = kzalloc(
+ clk_scaling->freq_table_sz *
+ sizeof(*(clk_scaling->devfreq_profile.freq_table)),
+ GFP_KERNEL);
+ if (!clk_scaling->devfreq_profile.freq_table)
+ return -ENOMEM;
+ clk_scaling->devfreq_profile.max_state = clk_scaling->freq_table_sz;
+
+ for (i = 0; i < clk_scaling->freq_table_sz; i++) {
+ clk_scaling->devfreq_profile.freq_table[i] =
+ clk_scaling->freq_table[i];
+ pr_debug("%s: freq[%d] = %u\n",
+ mmc_hostname(host), i, clk_scaling->freq_table[i]);
+ }
+
+ return 0;
+}
+
+/**
+ * mmc_init_devfreq_clk_scaling() - Initialize clock scaling
+ * @host: pointer to mmc host structure
+ *
+ * Initialize clock scaling for supported hosts. It is assumed that the caller
+ * ensure clock is running at maximum possible frequency before calling this
+ * function. Shall use struct devfreq_simple_ondemand_data to configure
+ * governor.
+ */
+int mmc_init_clk_scaling(struct mmc_host *host)
+{
+ int err;
+
+ if (!host || !host->card) {
+ pr_err("%s: unexpected host/card parameters\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ if (!mmc_can_scale_clk(host) ||
+ !host->bus_ops->change_bus_speed) {
+ pr_debug("%s: clock scaling is not supported\n",
+ mmc_hostname(host));
+ return 0;
+ }
+
+ pr_debug("registering %s dev (%p) to devfreq",
+ mmc_hostname(host),
+ mmc_classdev(host));
+
+ if (host->clk_scaling.devfreq) {
+ pr_err("%s: dev is already registered for dev %p\n",
+ mmc_hostname(host),
+ mmc_dev(host));
+ return -EPERM;
+ }
+ spin_lock_init(&host->clk_scaling.lock);
+ atomic_set(&host->clk_scaling.devfreq_abort, 0);
+ host->clk_scaling.curr_freq = host->ios.clock;
+ host->clk_scaling.clk_scaling_in_progress = false;
+ host->clk_scaling.need_freq_change = false;
+ host->clk_scaling.is_busy_started = false;
+
+ host->clk_scaling.devfreq_profile.polling_ms =
+ host->clk_scaling.polling_delay_ms;
+ host->clk_scaling.devfreq_profile.get_dev_status =
+ mmc_devfreq_get_dev_status;
+ host->clk_scaling.devfreq_profile.target = mmc_devfreq_set_target;
+ host->clk_scaling.devfreq_profile.initial_freq = host->ios.clock;
+
+ host->clk_scaling.ondemand_gov_data.simple_scaling = true;
+ host->clk_scaling.ondemand_gov_data.upthreshold =
+ host->clk_scaling.upthreshold;
+ host->clk_scaling.ondemand_gov_data.downdifferential =
+ host->clk_scaling.upthreshold - host->clk_scaling.downthreshold;
+
+ err = mmc_devfreq_create_freq_table(host);
+ if (err) {
+ pr_err("%s: fail to create devfreq frequency table\n",
+ mmc_hostname(host));
+ return err;
+ }
+
+ pr_debug("%s: adding devfreq with: upthreshold=%u downthreshold=%u polling=%u\n",
+ mmc_hostname(host),
+ host->clk_scaling.ondemand_gov_data.upthreshold,
+ host->clk_scaling.ondemand_gov_data.downdifferential,
+ host->clk_scaling.devfreq_profile.polling_ms);
+ host->clk_scaling.devfreq = devfreq_add_device(
+ mmc_classdev(host),
+ &host->clk_scaling.devfreq_profile,
+ "simple_ondemand",
+ &host->clk_scaling.ondemand_gov_data);
+ if (!host->clk_scaling.devfreq) {
+ pr_err("%s: unable to register with devfreq\n",
+ mmc_hostname(host));
+ return -EPERM;
+ }
+
+ pr_debug("%s: clk scaling is enabled for device %s (%p) with devfreq %p (clock = %uHz)\n",
+ mmc_hostname(host),
+ dev_name(mmc_classdev(host)),
+ mmc_classdev(host),
+ host->clk_scaling.devfreq,
+ host->ios.clock);
+
+ host->clk_scaling.enable = true;
+
+ return err;
+}
+EXPORT_SYMBOL(mmc_init_clk_scaling);
+
+/**
+ * mmc_exit_devfreq_clk_scaling() - Disable clock scaling
+ * @host: pointer to mmc host structure
+ *
+ * Disable clock scaling permanently.
+ */
+int mmc_exit_clk_scaling(struct mmc_host *host)
+{
+ int err;
+
+ if (!host) {
+ pr_err("%s: bad host parameter\n", __func__);
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ if (!mmc_can_scale_clk(host))
+ return 0;
+
+ if (!host->clk_scaling.devfreq) {
+ pr_err("%s: %s: no devfreq is assosiated with this device\n",
+ mmc_hostname(host), __func__);
+ return -EPERM;
+ }
+
+ err = devfreq_remove_device(host->clk_scaling.devfreq);
+ if (err) {
+ pr_err("%s: remove devfreq failed (%d)\n",
+ mmc_hostname(host), err);
+ return err;
+ }
+
+ kfree(host->clk_scaling.devfreq_profile.freq_table);
+
+ host->clk_scaling.devfreq = NULL;
+ atomic_set(&host->clk_scaling.devfreq_abort, 1);
+
+ kfree(host->clk_scaling.freq_table);
+ host->clk_scaling.freq_table = NULL;
+
+ pr_debug("%s: devfreq was removed\n", mmc_hostname(host));
+
+ return 0;
+}
+EXPORT_SYMBOL(mmc_exit_clk_scaling);
+
static inline void mmc_complete_cmd(struct mmc_request *mrq)
{
if (mrq->cap_cmd_during_tfr && !completion_done(&mrq->cmd_completion))
@@ -143,6 +690,9 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
struct mmc_command *cmd = mrq->cmd;
int err = cmd->error;
+ if (host->clk_scaling.is_busy_started)
+ mmc_clk_scaling_stop_busy(host, true);
+
/* Flag re-tuning needed on CRC errors */
if ((cmd->opcode != MMC_SEND_TUNING_BLOCK &&
cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200) &&
@@ -354,6 +904,12 @@ int mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
return err;
led_trigger_event(host->led, LED_FULL);
+
+ if (mmc_is_data_request(mrq)) {
+ mmc_deferred_scaling(host);
+ mmc_clk_scaling_start_busy(host, true);
+ }
+
__mmc_start_request(host, mrq);
return 0;
@@ -34,6 +34,7 @@ struct mmc_bus_ops {
int (*shutdown)(struct mmc_host *);
int (*hw_reset)(struct mmc_host *);
int (*sw_reset)(struct mmc_host *);
+ int (*change_bus_speed)(struct mmc_host *, unsigned long *);
};
void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);
@@ -46,6 +47,8 @@ struct device_node *mmc_of_find_child_device(struct mmc_host *host,
void mmc_set_chip_select(struct mmc_host *host, int mode);
void mmc_set_clock(struct mmc_host *host, unsigned int hz);
+int mmc_clk_update_freq(struct mmc_host *host,
+ unsigned long freq, enum mmc_load state);
void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode);
void mmc_set_bus_width(struct mmc_host *host, unsigned int width);
u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
@@ -91,6 +94,10 @@ static inline void mmc_delay(unsigned int ms)
void mmc_add_card_debugfs(struct mmc_card *card);
void mmc_remove_card_debugfs(struct mmc_card *card);
+extern bool mmc_can_scale_clk(struct mmc_host *host);
+extern int mmc_init_clk_scaling(struct mmc_host *host);
+extern int mmc_exit_clk_scaling(struct mmc_host *host);
+
int mmc_execute_tuning(struct mmc_card *card);
int mmc_hs200_to_hs400(struct mmc_card *card);
int mmc_hs400_to_hs200(struct mmc_card *card);
@@ -225,6 +225,43 @@ static int mmc_clock_opt_set(void *data, u64 val)
DEFINE_SIMPLE_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, mmc_clock_opt_set,
"%llu\n");
+#include <linux/delay.h>
+
+static int mmc_scale_get(void *data, u64 *val)
+{
+ struct mmc_host *host = data;
+
+ *val = host->clk_scaling.curr_freq;
+
+ return 0;
+}
+
+static int mmc_scale_set(void *data, u64 val)
+{
+ int err = 0;
+ struct mmc_host *host = data;
+
+ mmc_claim_host(host);
+
+ /* change frequency from sysfs manually */
+ err = mmc_clk_update_freq(host, val, host->clk_scaling.state);
+ if (err == -EAGAIN)
+ err = 0;
+ else if (err)
+ pr_err("%s: clock scale to %llu failed with error %d\n",
+ mmc_hostname(host), val, err);
+ else
+ pr_debug("%s: clock change to %llu finished successfully (%s)\n",
+ mmc_hostname(host), val, current->comm);
+
+ mmc_release_host(host);
+
+ return err;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(mmc_scale_fops, mmc_scale_get, mmc_scale_set,
+ "%llu\n");
+
void mmc_add_host_debugfs(struct mmc_host *host)
{
struct dentry *root;
@@ -253,6 +290,15 @@ void mmc_add_host_debugfs(struct mmc_host *host)
&mmc_clock_fops))
goto err_node;
+ if (!debugfs_create_file("scale", 0600, root, host,
+ &mmc_scale_fops))
+ goto err_node;
+
+ if (!debugfs_create_bool("skip_clk_scale_freq_update",
+ 0600, root,
+ &host->clk_scaling.skip_clk_scale_freq_update))
+ goto err_node;
+
#ifdef CONFIG_FAIL_MMC_REQUEST
if (fail_request)
setup_fault_attr(&fail_default_attr, fail_request);
@@ -32,6 +32,10 @@
#include "pwrseq.h"
#include "sdio_ops.h"
+#define MMC_DEVFRQ_DEFAULT_UP_THRESHOLD 35
+#define MMC_DEVFRQ_DEFAULT_DOWN_THRESHOLD 5
+#define MMC_DEVFRQ_DEFAULT_POLLING_MSEC 100
+
#define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev)
static DEFINE_IDA(mmc_host_ida);
@@ -435,6 +439,10 @@ int mmc_add_host(struct mmc_host *host)
return err;
led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
+ host->clk_scaling.upthreshold = MMC_DEVFRQ_DEFAULT_UP_THRESHOLD;
+ host->clk_scaling.downthreshold = MMC_DEVFRQ_DEFAULT_DOWN_THRESHOLD;
+ host->clk_scaling.polling_delay_ms = MMC_DEVFRQ_DEFAULT_POLLING_MSEC;
+ host->clk_scaling.skip_clk_scale_freq_update = false;
#ifdef CONFIG_DEBUG_FS
mmc_add_host_debugfs(host);
@@ -1526,6 +1526,170 @@ static int mmc_hs200_tuning(struct mmc_card *card)
}
/*
+ * Scale down from HS400 to HS in order to allow frequency change.
+ * This is needed for cards that doesn't support changing frequency in HS400
+ */
+static int mmc_scale_low(struct mmc_host *host, unsigned long freq)
+{
+ int err = 0;
+
+ mmc_set_timing(host, MMC_TIMING_LEGACY);
+ mmc_set_clock(host, MMC_HIGH_26_MAX_DTR);
+
+ err = mmc_select_hs(host->card);
+ if (err) {
+ pr_err("%s: %s: scaling low: failed (%d)\n",
+ mmc_hostname(host), __func__, err);
+ return err;
+ }
+
+ err = mmc_select_bus_width(host->card);
+ if (err < 0) {
+ pr_err("%s: %s: select_bus_width failed(%d)\n",
+ mmc_hostname(host), __func__, err);
+ return err;
+ }
+
+ mmc_set_clock(host, freq);
+
+ return 0;
+}
+
+/*
+ * Scale UP from HS to HS200/H400
+ */
+static int mmc_scale_high(struct mmc_host *host)
+{
+ int err = 0;
+
+ if (mmc_card_ddr52(host->card)) {
+ mmc_set_timing(host, MMC_TIMING_LEGACY);
+ mmc_set_clock(host, MMC_HIGH_26_MAX_DTR);
+ }
+
+ if (!host->card->ext_csd.strobe_support) {
+ if (!(host->card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200)) {
+ pr_err("%s: %s: card does not support HS200\n",
+ mmc_hostname(host), __func__);
+ WARN_ON(1);
+ return -EPERM;
+ }
+
+ err = mmc_select_hs200(host->card);
+ if (err) {
+ pr_err("%s: %s: selecting HS200 failed (%d)\n",
+ mmc_hostname(host), __func__, err);
+ return err;
+ }
+
+ mmc_set_bus_speed(host->card);
+
+ err = mmc_hs200_tuning(host->card);
+ if (err) {
+ pr_err("%s: %s: hs200 tuning failed (%d)\n",
+ mmc_hostname(host), __func__, err);
+ return err;
+ }
+
+ if (!(host->card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400)) {
+ pr_debug("%s: card does not support HS400\n",
+ mmc_hostname(host));
+ return 0;
+ }
+ }
+
+ err = mmc_select_hs400(host->card);
+ if (err) {
+ pr_err("%s: %s: select hs400 failed (%d)\n",
+ mmc_hostname(host), __func__, err);
+ return err;
+ }
+
+ return err;
+}
+
+static int mmc_set_clock_bus_speed(struct mmc_card *card, unsigned long freq)
+{
+ int err = 0;
+
+ if (freq == MMC_HS200_MAX_DTR)
+ err = mmc_scale_high(card->host);
+ else
+ err = mmc_scale_low(card->host, freq);
+
+ return err;
+}
+
+static inline unsigned long mmc_ddr_freq_accommodation(unsigned long freq)
+{
+ if (freq == MMC_HIGH_DDR_MAX_DTR)
+ return freq;
+
+ return freq/2;
+}
+
+/**
+ * mmc_change_bus_speed() - Change MMC card bus frequency at runtime
+ * @host: pointer to mmc host structure
+ * @freq: pointer to desired frequency to be set
+ *
+ * Change the MMC card bus frequency at runtime after the card is
+ * initialized. Callers are expected to make sure of the card's
+ * state (DATA/RCV/TRANSFER) before changing the frequency at runtime.
+ *
+ * If the frequency to change is greater than max. supported by card,
+ * *freq is changed to max. supported by card. If it is less than min.
+ * supported by host, *freq is changed to min. supported by host.
+ * Host is assumed to be calimed while calling this funciton.
+ */
+static int mmc_change_bus_speed(struct mmc_host *host, unsigned long *freq)
+{
+ int err = 0;
+ struct mmc_card *card;
+ unsigned long actual_freq;
+
+ card = host->card;
+
+ if (!card || !freq) {
+ err = -EINVAL;
+ goto out;
+ }
+ actual_freq = *freq;
+
+ WARN_ON(!host->claimed);
+
+ /*
+ * For scaling up/down HS400 we'll need special handling,
+ * for other timings we can simply do clock frequency change
+ */
+ if (mmc_card_hs400(card) ||
+ (!mmc_card_hs200(host->card) && *freq == MMC_HS200_MAX_DTR)) {
+ err = mmc_set_clock_bus_speed(card, *freq);
+ if (err) {
+ pr_err("%s: %s: failed (%d)to set bus and clock speed (freq=%lu)\n",
+ mmc_hostname(host), __func__, err, *freq);
+ goto out;
+ }
+ } else if (mmc_card_hs200(host->card)) {
+ mmc_set_clock(host, *freq);
+ err = mmc_hs200_tuning(host->card);
+ if (err) {
+ pr_warn("%s: %s: tuning execution failed %d\n",
+ mmc_hostname(card->host),
+ __func__, err);
+ mmc_set_clock(host, host->clk_scaling.curr_freq);
+ }
+ } else {
+ if (mmc_card_ddr52(host->card))
+ actual_freq = mmc_ddr_freq_accommodation(*freq);
+ mmc_set_clock(host, actual_freq);
+ }
+
+out:
+ return err;
+}
+
+/*
* Handle the detection and initialisation of a card.
*
* In the case of a resume, "oldcard" will contain the card
@@ -1751,6 +1915,16 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
}
}
+ card->clk_scaling_lowest = host->f_min;
+ if ((card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS400) ||
+ (card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS200))
+ card->clk_scaling_highest = card->ext_csd.hs200_max_dtr;
+ else if ((card->mmc_avail_type & EXT_CSD_CARD_TYPE_HS) ||
+ (card->mmc_avail_type & EXT_CSD_CARD_TYPE_DDR_52))
+ card->clk_scaling_highest = card->ext_csd.hs_max_dtr;
+ else
+ card->clk_scaling_highest = card->csd.max_dtr;
+
/*
* Choose the power class with selected bus interface
*/
@@ -1942,6 +2116,7 @@ static int mmc_poweroff_notify(struct mmc_card *card, unsigned int notify_type)
*/
static void mmc_remove(struct mmc_host *host)
{
+ mmc_exit_clk_scaling(host);
mmc_remove_card(host->card);
host->card = NULL;
}
@@ -2064,6 +2239,13 @@ static int mmc_shutdown(struct mmc_host *host)
int err = 0;
/*
+ * Exit clock scaling so that it doesn't kick in after
+ * power off notification is sent
+ */
+ if (host->caps2 & MMC_CAP2_CLK_SCALE)
+ mmc_exit_clk_scaling(host);
+
+ /*
* In a specific case for poweroff notify, we need to resume the card
* before we can shutdown it properly.
*/
@@ -2132,6 +2314,7 @@ static int mmc_can_reset(struct mmc_card *card)
static int _mmc_hw_reset(struct mmc_host *host)
{
struct mmc_card *card = host->card;
+ int ret;
/*
* In the case of recovery, we can't expect flushing the cache to work
@@ -2151,7 +2334,15 @@ static int _mmc_hw_reset(struct mmc_host *host)
mmc_power_cycle(host, card->ocr);
mmc_pwrseq_reset(host);
}
- return mmc_init_card(host, card->ocr, card);
+
+ ret = mmc_init_card(host, card->ocr, card);
+ if (ret) {
+ pr_err("%s: %s: mmc_init_card failed (%d)\n",
+ mmc_hostname(host), __func__, ret);
+ return ret;
+ }
+
+ return ret;
}
static const struct mmc_bus_ops mmc_ops = {
@@ -2164,6 +2355,7 @@ static int _mmc_hw_reset(struct mmc_host *host)
.alive = mmc_alive,
.shutdown = mmc_shutdown,
.hw_reset = _mmc_hw_reset,
+ .change_bus_speed = mmc_change_bus_speed,
};
/*
@@ -2220,6 +2412,12 @@ int mmc_attach_mmc(struct mmc_host *host)
goto remove_card;
mmc_claim_host(host);
+ err = mmc_init_clk_scaling(host);
+ if (err) {
+ mmc_release_host(host);
+ goto remove_card;
+ }
+
return 0;
remove_card:
@@ -892,7 +892,10 @@ unsigned mmc_sd_get_max_clock(struct mmc_card *card)
{
unsigned max_dtr = (unsigned int)-1;
- if (mmc_card_hs(card)) {
+ if (mmc_card_uhs(card)) {
+ if (max_dtr > card->sw_caps.uhs_max_dtr)
+ max_dtr = card->sw_caps.uhs_max_dtr;
+ } else if (mmc_card_hs(card)) {
if (max_dtr > card->sw_caps.hs_max_dtr)
max_dtr = card->sw_caps.hs_max_dtr;
} else if (max_dtr > card->csd.max_dtr) {
@@ -1059,6 +1062,9 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
}
}
+ card->clk_scaling_highest = mmc_sd_get_max_clock(card);
+ card->clk_scaling_lowest = host->f_min;
+
if (host->caps2 & MMC_CAP2_AVOID_3_3V &&
host->ios.signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
pr_err("%s: Host failed to negotiate down from 3.3V\n",
@@ -1082,6 +1088,7 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
*/
static void mmc_sd_remove(struct mmc_host *host)
{
+ mmc_exit_clk_scaling(host);
mmc_remove_card(host->card);
host->card = NULL;
}
@@ -1228,6 +1235,62 @@ static int mmc_sd_hw_reset(struct mmc_host *host)
return mmc_sd_init_card(host, host->card->ocr, host->card);
}
+/**
+ * mmc_sd_change_bus_speed() - Change SD card bus frequency at runtime
+ * @host: pointer to mmc host structure
+ * @freq: pointer to desired frequency to be set
+ *
+ * Change the SD card bus frequency at runtime after the card is
+ * initialized. Callers are expected to make sure of the card's
+ * state (DATA/RCV/TRANSFER) beforing changing the frequency at runtime.
+ *
+ * If the frequency to change is greater than max. supported by card,
+ * *freq is changed to max. supported by card and if it is less than min.
+ * supported by host, *freq is changed to min. supported by host.
+ */
+static int mmc_sd_change_bus_speed(struct mmc_host *host, unsigned long *freq)
+{
+ int err = 0;
+ struct mmc_card *card;
+
+ mmc_claim_host(host);
+ /*
+ * Assign card pointer after claiming host to avoid race
+ * conditions that may arise during removal of the card.
+ */
+ card = host->card;
+
+ /* sanity checks */
+ if (!card || !freq) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ mmc_set_clock(host, (unsigned int) (*freq));
+
+ if (!mmc_host_is_spi(card->host) && mmc_card_uhs(card)
+ && card->host->ops->execute_tuning) {
+ /*
+ * We try to probe host driver for tuning for any
+ * frequency, it is host driver responsibility to
+ * perform actual tuning only when required.
+ */
+ err = card->host->ops->execute_tuning(card->host,
+ MMC_SEND_TUNING_BLOCK);
+
+ if (err) {
+ pr_warn("%s: %s: tuning execution failed %d. Restoring to previous clock %lu\n",
+ mmc_hostname(card->host), __func__, err,
+ host->clk_scaling.curr_freq);
+ mmc_set_clock(host, host->clk_scaling.curr_freq);
+ }
+ }
+
+out:
+ mmc_release_host(host);
+ return err;
+}
+
static const struct mmc_bus_ops mmc_sd_ops = {
.remove = mmc_sd_remove,
.detect = mmc_sd_detect,
@@ -1238,6 +1301,7 @@ static int mmc_sd_hw_reset(struct mmc_host *host)
.alive = mmc_sd_alive,
.shutdown = mmc_sd_suspend,
.hw_reset = mmc_sd_hw_reset,
+ .change_bus_speed = mmc_sd_change_bus_speed,
};
/*
@@ -1292,6 +1356,12 @@ int mmc_attach_sd(struct mmc_host *host)
goto remove_card;
mmc_claim_host(host);
+ err = mmc_init_clk_scaling(host);
+ if (err) {
+ mmc_release_host(host);
+ goto remove_card;
+ }
+
return 0;
remove_card:
@@ -1705,6 +1705,43 @@ static int sdhci_msm_register_vreg(struct sdhci_msm_host *msm_host)
MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
+int sdhci_msm_dt_get_array(struct device *dev, const char *prop_name,
+ u32 **out, int *len, u32 size)
+{
+ int ret = 0;
+ struct device_node *np = dev->of_node;
+ size_t sz;
+ u32 *arr = NULL;
+
+ if (!of_get_property(np, prop_name, len)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ sz = *len = *len / sizeof(*arr);
+ if (sz <= 0 || (size > 0 && (sz > size))) {
+ dev_err(dev, "%s invalid size\n", prop_name);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ arr = devm_kzalloc(dev, sz * sizeof(*arr), GFP_KERNEL);
+ if (!arr) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = of_property_read_u32_array(np, prop_name, arr, sz);
+ if (ret < 0) {
+ dev_err(dev, "%s failed reading array %d\n", prop_name, ret);
+ goto out;
+ }
+ *out = arr;
+out:
+ if (ret)
+ *len = 0;
+ return ret;
+}
+
static const struct sdhci_ops sdhci_msm_ops = {
.reset = sdhci_reset,
.set_clock = sdhci_msm_set_clock,
@@ -36,6 +36,9 @@
#endif
#include "sdhci-pltfm.h"
+int sdhci_msm_dt_get_array(struct device *dev, const char *prop_name,
+ u32 **out, int *len, u32 size);
+
unsigned int sdhci_pltfm_clk_get_max_clock(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -101,6 +104,14 @@ void sdhci_get_of_property(struct platform_device *pdev)
of_property_read_u32(np, "clock-frequency", &pltfm_host->clock);
+ if (sdhci_msm_dt_get_array(&pdev->dev, "qcom,devfreq,freq-table",
+ &host->mmc->clk_scaling.pltfm_freq_table,
+ &host->mmc->clk_scaling.pltfm_freq_table_sz, 0))
+ pr_debug("no clock scaling frequencies were supplied\n");
+ else if (!host->mmc->clk_scaling.pltfm_freq_table ||
+ !host->mmc->clk_scaling.pltfm_freq_table_sz)
+ pr_err("bad dts clock scaling frequencies\n");
+
if (of_find_property(np, "keep-power-in-suspend", NULL))
host->mmc->pm_caps |= MMC_PM_KEEP_POWER;
@@ -2427,6 +2427,32 @@ static void sdhci_card_event(struct mmc_host *mmc)
spin_unlock_irqrestore(&host->lock, flags);
}
+static inline void sdhci_update_power_policy(struct sdhci_host *host,
+ enum sdhci_power_policy policy)
+{
+ host->power_policy = policy;
+}
+
+static int sdhci_notify_load(struct mmc_host *mmc, enum mmc_load state)
+{
+ int err = 0;
+ struct sdhci_host *host = mmc_priv(mmc);
+
+ switch (state) {
+ case MMC_LOAD_HIGH:
+ sdhci_update_power_policy(host, SDHCI_PERFORMANCE_MODE);
+ break;
+ case MMC_LOAD_LOW:
+ sdhci_update_power_policy(host, SDHCI_POWER_SAVE_MODE);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ return err;
+}
+
static const struct mmc_host_ops sdhci_ops = {
.request = sdhci_request,
.post_req = sdhci_post_req,
@@ -2441,6 +2467,7 @@ static void sdhci_card_event(struct mmc_host *mmc)
.execute_tuning = sdhci_execute_tuning,
.card_event = sdhci_card_event,
.card_busy = sdhci_card_busy,
+ .notify_load = sdhci_notify_load,
};
/*****************************************************************************\
@@ -346,6 +346,12 @@ enum sdhci_cookie {
COOKIE_MAPPED, /* mapped by sdhci_prepare_data() */
};
+enum sdhci_power_policy {
+ SDHCI_PERFORMANCE_MODE,
+ SDHCI_POWER_SAVE_MODE,
+ SDHCI_POWER_POLICY_NUM /* Always keep this one last */
+};
+
struct sdhci_host {
/* Data set by hardware interface driver */
const char *hw_name; /* Hardware bus name */
@@ -562,6 +568,8 @@ struct sdhci_host {
/* Delay (ms) between tuning commands */
int tuning_delay;
+ enum sdhci_power_policy power_policy;
+
/* Host SDMA buffer boundary. */
u32 sdma_boundary;
@@ -245,6 +245,10 @@ struct mmc_card {
struct mmc_host *host; /* the host this device belongs to */
struct device dev; /* the device */
u32 ocr; /* the current OCR setting */
+ unsigned long clk_scaling_lowest; /* lowest scaleable*/
+ /* frequency */
+ unsigned long clk_scaling_highest; /* highest scaleable */
+
unsigned int rca; /* relative card address of device */
unsigned int type; /* card type */
#define MMC_TYPE_MMC 0 /* MMC card */
@@ -308,6 +312,7 @@ struct mmc_card {
unsigned int nr_parts;
unsigned int bouncesz; /* Bounce buffer size */
+ unsigned int part_curr;
};
static inline bool mmc_large_sector(struct mmc_card *card)
@@ -12,6 +12,7 @@
#include <linux/sched.h>
#include <linux/device.h>
+#include <linux/devfreq.h>
#include <linux/fault-inject.h>
#include <linux/mmc/core.h>
@@ -82,6 +83,12 @@ struct mmc_ios {
struct mmc_host;
+/* states to represent load on the host */
+enum mmc_load {
+ MMC_LOAD_HIGH,
+ MMC_LOAD_LOW,
+};
+
struct mmc_host_ops {
/*
* It is optional for the host to implement pre_req and post_req in
@@ -161,6 +168,7 @@ struct mmc_host_ops {
*/
int (*multi_io_quirk)(struct mmc_card *card,
unsigned int direction, int blk_size);
+ int (*notify_load)(struct mmc_host *, enum mmc_load);
};
struct mmc_cqe_ops {
@@ -260,9 +268,60 @@ struct mmc_ctx {
struct task_struct *task;
};
+/**
+ * struct mmc_devfeq_clk_scaling - main context for MMC clock scaling logic
+ *
+ * @lock: spinlock to protect statistics
+ * @devfreq: struct that represent mmc-host as a client for devfreq
+ * @devfreq_profile: MMC device profile, mostly polling interval and callbacks
+ * @ondemand_gov_data: struct supplied to ondemmand governor (thresholds)
+ * @state: load state, can be HIGH or LOW. used to notify mmc_host_ops callback
+ * @start_busy: timestamped armed once a data request is started
+ * @measure_interval_start: timestamped armed once a measure interval started
+ * @devfreq_abort: flag to sync between different contexts relevant to devfreq
+ * @skip_clk_scale_freq_update: flag that enable/disable frequency change
+ * @freq_table_sz: table size of frequencies supplied to devfreq
+ * @freq_table: frequencies table supplied to devfreq
+ * @curr_freq: current frequency
+ * @polling_delay_ms: polling interval for status collection used by devfreq
+ * @upthreshold: up-threshold supplied to ondemand governor
+ * @downthreshold: down-threshold supplied to ondemand governor
+ * @need_freq_change: flag indicating if a frequency change is required
+ * @clk_scaling_in_progress: flag indicating if there's ongoing frequency change
+ * @is_busy_started: flag indicating if a request is handled by the HW
+ * @enable: flag indicating if the clock scaling logic is enabled for this host
+ */
+struct mmc_devfeq_clk_scaling {
+ spinlock_t lock;
+ struct devfreq *devfreq;
+ struct devfreq_dev_profile devfreq_profile;
+ struct devfreq_simple_ondemand_data ondemand_gov_data;
+ enum mmc_load state;
+ ktime_t start_busy;
+ ktime_t measure_interval_start;
+ atomic_t devfreq_abort;
+ bool skip_clk_scale_freq_update;
+ int freq_table_sz;
+ int pltfm_freq_table_sz;
+ u32 *freq_table;
+ u32 *pltfm_freq_table;
+ unsigned long total_busy_time_us;
+ unsigned long target_freq;
+ unsigned long curr_freq;
+ unsigned long polling_delay_ms;
+ unsigned int upthreshold;
+ unsigned int downthreshold;
+ bool need_freq_change;
+ bool clk_scaling_in_progress;
+ bool is_busy_started;
+ bool enable;
+};
+
+
struct mmc_host {
struct device *parent;
struct device class_dev;
+ struct mmc_devfeq_clk_scaling clk_scaling;
int index;
const struct mmc_host_ops *ops;
struct mmc_pwrseq *pwrseq;
@@ -360,6 +419,7 @@ struct mmc_host {
#define MMC_CAP2_CQE (1 << 23) /* Has eMMC command queue engine */
#define MMC_CAP2_CQE_DCMD (1 << 24) /* CQE can issue a direct command */
#define MMC_CAP2_AVOID_3_3V (1 << 25) /* Host must negotiate down from 3.3V */
+#define MMC_CAP2_CLK_SCALE (1 << 26) /* Allow dynamic clk scaling */
int fixed_drv_type; /* fixed driver type for non-removable media */
@@ -523,6 +583,16 @@ static inline int mmc_regulator_set_vqmmc(struct mmc_host *mmc,
u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max);
int mmc_regulator_get_supply(struct mmc_host *mmc);
+static inline void mmc_host_clear_sdr104(struct mmc_host *host)
+{
+ host->caps &= ~MMC_CAP_UHS_SDR104;
+}
+
+static inline void mmc_host_set_sdr104(struct mmc_host *host)
+{
+ host->caps |= MMC_CAP_UHS_SDR104;
+}
+
static inline int mmc_card_is_removable(struct mmc_host *host)
{
return !(host->caps & MMC_CAP_NONREMOVABLE);