Patchwork [U-Boot,PATCHv2,6/8] drivers: mtd: qspi: Add quad read support

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Submitter Poddar, Sourav
Date July 23, 2013, 8:59 a.m.
Message ID <1374569979-28660-7-git-send-email-sourav.poddar@ti.com>
Download mbox | patch
Permalink /patch/260993/
State Superseded
Delegated to: Jagannadha Sutradharudu Teki
Headers show

Comments

Poddar, Sourav - July 23, 2013, 8:59 a.m.
From: Ravikumar Kattekola <rk@ti.com>

Add Quad read mode (6 pin interface) support to spi flash
and ti qspi driver.

Quad mode (0x6bh on spansion) uses two extra pins (D2 and D3) for
data transfer apart from the usual D0 and D1 pins thus transfering
4 bits per cycle.

Signed-off-by: Ravikumar Kattekola <rk@ti.com>
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
---
 drivers/mtd/spi/spi_flash.c          |  110 +++++++++++++++++++++++++++++++++-
 drivers/mtd/spi/spi_flash_internal.h |    2 +
 drivers/spi/ti_qspi.c                |   18 ++++--
 include/configs/dra7xx_evm.h         |    1 +
 include/spi.h                        |    2 +
 5 files changed, 127 insertions(+), 6 deletions(-)
Wolfgang Denk - July 23, 2013, 9:28 a.m.
Dear Sourav Poddar,

In message <1374569979-28660-7-git-send-email-sourav.poddar@ti.com> you wrote:
> From: Ravikumar Kattekola <rk@ti.com>
> 
> Add Quad read mode (6 pin interface) support to spi flash
> and ti qspi driver.
> 
> Quad mode (0x6bh on spansion) uses two extra pins (D2 and D3) for
> data transfer apart from the usual D0 and D1 pins thus transfering
> 4 bits per cycle.
> 
> Signed-off-by: Ravikumar Kattekola <rk@ti.com>
> Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
> ---
>  drivers/mtd/spi/spi_flash.c          |  110 +++++++++++++++++++++++++++++++++-
>  drivers/mtd/spi/spi_flash_internal.h |    2 +
>  drivers/spi/ti_qspi.c                |   18 ++++--
>  include/configs/dra7xx_evm.h         |    1 +
>  include/spi.h                        |    2 +
>  5 files changed, 127 insertions(+), 6 deletions(-)

Again: change log missing, checkpatch issues (line over 80
characters).

Please fix.

Best regards,

Wolfgang Denk

Patch

diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 5f8db7b..c81f402 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -42,7 +42,12 @@  static int spi_flash_read_write(struct spi_slave *spi,
 		debug("SF: Failed to send command (%zu bytes): %d\n",
 				cmd_len, ret);
 	} else if (data_len != 0) {
-		ret = spi_xfer(spi, data_len * 8, data_out, data_in, SPI_XFER_END);
+		if (spi->quad_enable)
+			flags = SPI_6WIRE;
+		else
+			flags = 0;
+
+		ret = spi_xfer(spi, data_len * 8, data_out, data_in, flags | SPI_XFER_END);
 		if (ret)
 			debug("SF: Failed to transfer %zu bytes of data: %d\n",
 					data_len, ret);
@@ -271,6 +276,51 @@  int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
 	return ret;
 }
 
+int spi_flash_cmd_read_quad(struct spi_flash *flash, u32 offset,
+		size_t len, void *data)
+{
+	struct spi_slave *spi = flash->spi;
+
+	unsigned long page_addr, byte_addr, page_size;
+	size_t chunk_len, actual;
+	int ret = 0;
+	u8 cmd[5];
+
+	spi->quad_enable = 1;
+	/* Handle memory-mapped SPI */
+	if (flash->memory_map)
+		memcpy(data, flash->memory_map + offset, len);
+
+	page_size = flash->page_size;
+	page_addr = offset / page_size;
+	byte_addr = offset % page_size;
+
+	cmd[0] = CMD_READ_ARRAY_QUAD;
+	for (actual = 0; actual < len; actual += chunk_len) {
+		chunk_len = min(len - actual, page_size - byte_addr);
+
+		cmd[1] = page_addr >> 8;
+		cmd[2] = page_addr;
+		cmd[3] = byte_addr;
+		cmd[4] = 0x0;
+
+		ret = spi_flash_read_common(flash, cmd, sizeof(cmd),
+				data + actual, chunk_len);
+		if (ret < 0) {
+			debug("SF: read failed");
+			break;
+		}
+
+		byte_addr += chunk_len;
+		if (byte_addr == page_size) {
+			page_addr++;
+			byte_addr = 0;
+		}
+	}
+
+	return ret;
+}
+
 int spi_flash_cmd_read_fast(struct spi_flash *flash, u32 offset,
 		size_t len, void *data)
 {
@@ -424,6 +474,56 @@  int spi_flash_bank_config(struct spi_flash *flash, u8 idcode0)
 }
 #endif
 
+int spi_flash_en_quad_mode(struct spi_flash *flash)
+{
+	u8 stat, con, cd;
+	u16 cr;
+	int ret;
+	cd = CMD_WRITE_STATUS;
+
+	ret = spi_flash_cmd_write_enable(flash);
+	if (ret < 0) {
+		debug("SF: enabling write failed\n");
+		goto out;
+	}
+	ret = spi_flash_cmd(flash->spi, CMD_READ_STATUS, &stat, 1);
+	ret = spi_flash_cmd(flash->spi, CMD_READ_CONFIG, &con, 1);
+	if (ret < 0) {
+		debug("%s: SF: read CR failed\n", __func__);
+		goto out;
+	}
+	/* Byte 1 - status reg, Byte 2 - config reg */
+	cr = ((con | (0x1 << 1)) << 8) | (stat << 0);
+
+	ret = spi_flash_cmd_write(flash->spi, &cd, 1, &cr, 2);
+	if (ret) {
+		debug("SF: fail to write conf register\n");
+		goto out;
+	}
+
+	ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+	if (ret < 0) {
+		debug("SF: write conf register timed out\n");
+		goto out;
+	}
+
+	ret = spi_flash_cmd(flash->spi, CMD_READ_STATUS, &stat, 1);
+	ret = spi_flash_cmd(flash->spi, CMD_READ_CONFIG, &con, 1);
+	if (ret < 0) {
+		debug("%s: SF: read CR failed\n", __func__);
+		goto out;
+	}
+	debug("%s: *** CR = %x\n", __func__, con);
+
+	ret = spi_flash_cmd_write_disable(flash);
+	if (ret < 0) {
+		debug("SF: disabling write failed\n");
+		goto out;
+	}
+out:
+	return ret;
+}
+
 #ifdef CONFIG_OF_CONTROL
 int spi_flash_decode_fdt(const void *blob, struct spi_flash *flash)
 {
@@ -578,6 +678,10 @@  struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
 		goto err_manufacturer_probe;
 #endif
 
+#ifdef CONFIG_SF_QUAD_RD
+	spi_flash_en_quad_mode(flash);
+#endif
+
 #ifdef CONFIG_OF_CONTROL
 	if (spi_flash_decode_fdt(gd->fdt_blob, flash)) {
 		debug("SF: FDT decode error\n");
@@ -628,7 +732,11 @@  void *spi_flash_do_alloc(int offset, int size, struct spi_slave *spi,
 	flash->name = name;
 	flash->poll_cmd = CMD_READ_STATUS;
 
+#ifdef CONFIG_SF_QUAD_RD
+	flash->read = spi_flash_cmd_read_quad;
+#else
 	flash->read = spi_flash_cmd_read_fast;
+#endif
 	flash->write = spi_flash_cmd_write_multi;
 	flash->erase = spi_flash_cmd_erase;
 
diff --git a/drivers/mtd/spi/spi_flash_internal.h b/drivers/mtd/spi/spi_flash_internal.h
index af1afa9..1205a7a 100644
--- a/drivers/mtd/spi/spi_flash_internal.h
+++ b/drivers/mtd/spi/spi_flash_internal.h
@@ -17,11 +17,13 @@ 
 
 #define CMD_READ_ARRAY_SLOW		0x03
 #define CMD_READ_ARRAY_FAST		0x0b
+#define CMD_READ_ARRAY_QUAD            0x6b
 
 #define CMD_WRITE_STATUS		0x01
 #define CMD_PAGE_PROGRAM		0x02
 #define CMD_WRITE_DISABLE		0x04
 #define CMD_READ_STATUS			0x05
+#define CMD_READ_CONFIG			0x35
 #define CMD_FLAG_STATUS			0x70
 #define CMD_WRITE_ENABLE		0x06
 #define CMD_ERASE_4K			0x20
diff --git a/drivers/spi/ti_qspi.c b/drivers/spi/ti_qspi.c
index 1973b85..12bba11 100644
--- a/drivers/spi/ti_qspi.c
+++ b/drivers/spi/ti_qspi.c
@@ -72,6 +72,7 @@  static struct qspi_regs *qspi = (struct qspi_regs *)QSPI_BASE;
 #define QSPI_RD_SNGL			(1 << 16)
 #define QSPI_WR_SNGL			(2 << 16)
 #define QSPI_INVAL			(4 << 16)
+#define QSPI_RD_QUAD			(7 << 16)
 
 /* Device Control */
 #define QSPI_DD(m, n)			(m << (3 + n*8))
@@ -235,10 +236,17 @@  int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
 			debug("tx done, status %08x\n", status);
 		}
 		if (rxp) {
-			debug("rx cmd %08x dc %08x\n",
-			      qslave->cmd | QSPI_RD_SNGL, qslave->dc);
-			writel(qslave->dc, &qspi->spi_dc);
-			writel(qslave->cmd | QSPI_RD_SNGL, &qspi->spi_cmd);
+			if (flags & SPI_6WIRE) {
+				debug("rx cmd %08x dc %08x\n",
+				      qslave->cmd | QSPI_RD_QUAD, qslave->dc);
+				writel(qslave->cmd | QSPI_RD_QUAD,
+				       &qspi->spi_cmd);
+			} else {
+				debug("rx cmd %08x dc %08x\n",
+				      qslave->cmd | QSPI_RD_SNGL, qslave->dc);
+				writel(qslave->cmd | QSPI_RD_SNGL,
+				       &qspi->spi_cmd);
+			}
 			status = readl(&qspi->spi_status);
 			timeout = QSPI_TIMEOUT;
 			while ((status & QSPI_WC_BUSY) != QSPI_XFER_DONE) {
@@ -250,7 +258,7 @@  int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
 			}
 			*rxp++ = readl(&qspi->spi_data);
 			debug("rx done, status %08x, read %02x\n",
-			      status, *(rxp-1));
+				 status, *(rxp-1));
 		}
 	}
 
diff --git a/include/configs/dra7xx_evm.h b/include/configs/dra7xx_evm.h
index f30a795..9d11820 100644
--- a/include/configs/dra7xx_evm.h
+++ b/include/configs/dra7xx_evm.h
@@ -50,6 +50,7 @@ 
 #define CONFIG_SPI_FLASH_SPANSION
 #define CONFIG_CMD_SF
 #define CONFIG_CMD_SPI
+#define CONFIG_SF_QUAD_RD
 #define CONFIG_SF_DEFAULT_SPEED                12000000
 #define CONFIG_DEFAULT_SPI_MODE                SPI_MODE_3
 
diff --git a/include/spi.h b/include/spi.h
index e8e6544..d5a0ead 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -39,6 +39,7 @@ 
 #define	SPI_LOOP	0x20			/* loopback mode */
 #define	SPI_SLAVE	0x40			/* slave mode */
 #define	SPI_PREAMBLE	0x80			/* Skip preamble bytes */
+#define	SPI_6WIRE       0x10                    /* 4 data lines */
 
 /* SPI transfer flags */
 #define SPI_XFER_BEGIN	0x01			/* Assert CS before transfer */
@@ -61,6 +62,7 @@  struct spi_slave {
 	unsigned int	bus;
 	unsigned int	cs;
 	unsigned int max_write_size;
+	bool quad_enable;
 };
 
 /*-----------------------------------------------------------------------