path: root/target/linux/brcm47xx/patches-3.9/070-bcma-add-functions-to-write-to-serial-flash.patch

--- a/drivers/bcma/driver_chipcommon_sflash.c
+++ b/drivers/bcma/driver_chipcommon_sflash.c
@@ -1,6 +1,9 @@
 /*
  * Broadcom specific AMBA
  * ChipCommon serial flash interface
+ * Copyright 2011, Jonas Gorski <jonas.gorski@gmail.com>
+ * Copyright 2011, 2012, Hauke Mehrtens <hauke@hauke-m.de>
+ * Copyright 2010, Broadcom Corporation
  *
  * Licensed under the GNU/GPL. See COPYING for details.
  */
@@ -8,7 +11,11 @@
 #include "bcma_private.h"
 
 #include <linux/platform_device.h>
+#include <linux/delay.h>
 #include <linux/bcma/bcma.h>
+#include <linux/bcma/bcma_driver_chipcommon.h>
+
+#define NUM_RETRIES	3
 
 static struct resource bcma_sflash_resource = {
 	.name	= "bcma_sflash",
@@ -18,7 +25,7 @@ static struct resource bcma_sflash_resou
 };
 
 struct platform_device bcma_sflash_dev = {
-	.name		= "bcma_sflash",
+	.name		= "bcm47xx-sflash",
 	.resource	= &bcma_sflash_resource,
 	.num_resources	= 1,
 };
@@ -84,11 +91,185 @@ static void bcma_sflash_cmd(struct bcma_
 	bcma_err(cc->core->bus, "SFLASH control command failed (timeout)!\n");
 }
 
+static void bcma_sflash_write_u8(struct bcma_drv_cc *cc, u32 offset, u8 byte)
+{
+	bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset);
+	bcma_cc_write32(cc, BCMA_CC_FLASHDATA, byte);
+}
+
+/* Poll for command completion. Returns zero when complete. */
+static int bcma_sflash_poll(struct bcm47xxsflash *dev, u32 offset)
+{
+	struct bcma_drv_cc *cc = dev->bcc;
+
+	if (offset >= cc->sflash.size)
+		return -22;
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		/* Check for ST Write In Progress bit */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RDSR);
+		return bcma_cc_read32(cc, BCMA_CC_FLASHDATA)
+				& BCMA_CC_FLASHDATA_ST_WIP;
+	case BCMA_CC_FLASHT_ATSER:
+		/* Check for Atmel Ready bit */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_STATUS);
+		return !(bcma_cc_read32(cc, BCMA_CC_FLASHDATA)
+				& BCMA_CC_FLASHDATA_AT_READY);
+	}
+
+	return 0;
+}
+
+static int sflash_st_write(struct bcm47xxsflash *dev, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	int written = 1;
+	struct bcma_drv_cc *cc = dev->bcc;
+
+	/* Enable writes */
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_WREN);
+	bcma_sflash_write_u8(cc, offset, *buf++);
+	/* Issue a page program with CSA bit set */
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_CSA | BCMA_CC_FLASHCTL_ST_PP);
+	offset++;
+	len--;
+	while (len > 0) {
+		if ((offset & 255) == 0) {
+			/* Page boundary, poll droping cs and return */
+			bcma_cc_write32(cc, BCMA_CC_FLASHCTL, 0);
+			udelay(1);
+			if (!bcma_sflash_poll(dev, offset)) {
+				/* Flash rejected command */
+				return -EAGAIN;
+			}
+			return written;
+		} else {
+			/* Write single byte */
+			bcma_sflash_cmd(cc,
+					BCMA_CC_FLASHCTL_ST_CSA |
+					*buf++);
+		}
+		written++;
+		offset++;
+		len--;
+	}
+	/* All done, drop cs & poll */
+	bcma_cc_write32(cc, BCMA_CC_FLASHCTL, 0);
+	udelay(1);
+	if (!bcma_sflash_poll(dev, offset)) {
+		/* Flash rejected command */
+		return -EAGAIN;
+	}
+	return written;
+}
+
+static int sflash_at_write(struct bcm47xxsflash *dev, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct bcma_drv_cc *cc = dev->bcc;
+	u32 page, byte, mask;
+	int ret = 0;
+
+	mask = dev->blocksize - 1;
+	page = (offset & ~mask) << 1;
+	byte = offset & mask;
+	/* Read main memory page into buffer 1 */
+	if (byte || (len < dev->blocksize)) {
+		int i = 100;
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, page);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_BUF1_LOAD);
+		/* 250 us for AT45DB321B */
+		while (i > 0 && bcma_sflash_poll(dev, offset)) {
+			udelay(10);
+			i--;
+		}
+		BUG_ON(!bcma_sflash_poll(dev, offset));
+	}
+	/* Write into buffer 1 */
+	for (ret = 0; (ret < (int)len) && (byte < dev->blocksize); ret++) {
+		bcma_sflash_write_u8(cc, byte++, *buf++);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_BUF1_WRITE);
+	}
+	/* Write buffer 1 into main memory page */
+	bcma_cc_write32(cc, BCMA_CC_FLASHADDR, page);
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_BUF1_PROGRAM);
+
+	return ret;
+}
+
+/* Write len bytes starting at offset into buf. Returns number of bytes
+ * written. Caller should poll for completion.
+ */
+static int bcma_sflash_write(struct bcm47xxsflash *dev, u32 offset, u32 len,
+		      const u8 *buf)
+{
+	int ret = 0, tries = NUM_RETRIES;
+	struct bcma_drv_cc *cc = dev->bcc;
+
+	if (!len)
+		return 0;
+
+	if ((offset + len) > cc->sflash.size)
+		return -EINVAL;
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		do {
+			ret = sflash_st_write(dev, offset, len, buf);
+			tries--;
+		} while (ret == -EAGAIN && tries > 0);
+
+		if (ret == -EAGAIN && tries == 0) {
+			bcma_info(cc->core->bus, "ST Flash rejected write\n");
+			ret = -EIO;
+		}
+		break;
+	case BCMA_CC_FLASHT_ATSER:
+		ret = sflash_at_write(dev, offset, len, buf);
+		break;
+	}
+
+	return ret;
+}
+
+/* Erase a region. Returns number of bytes scheduled for erasure.
+ * Caller should poll for completion.
+ */
+static int bcma_sflash_erase(struct bcm47xxsflash *dev, u32 offset)
+{
+	struct bcma_drv_cc *cc = dev->bcc;
+
+	if (offset >= cc->sflash.size)
+		return -EINVAL;
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_WREN);
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset);
+		/* Newer flashes have "sub-sectors" which can be erased independently
+		 * with a new command: ST_SSE. The ST_SE command erases 64KB just as
+		 * before.
+		 */
+		if (dev->blocksize < (64 * 1024))
+			bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_SSE);
+		else
+			bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_SE);
+		return dev->blocksize;
+	case BCMA_CC_FLASHT_ATSER:
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset << 1);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_PAGE_ERASE);
+		return dev->blocksize;
+	}
+
+	return 0;
+}
+
 /* Initialize serial flash access */
 int bcma_sflash_init(struct bcma_drv_cc *cc)
 {
 	struct bcma_bus *bus = cc->core->bus;
-	struct bcma_sflash *sflash = &cc->sflash;
+	struct bcm47xxsflash *sflash = &cc->sflash;
 	const struct bcma_sflash_tbl_e *e;
 	u32 id, id2;
 
@@ -150,6 +331,11 @@ int bcma_sflash_init(struct bcma_drv_cc
 	sflash->numblocks = e->numblocks;
 	sflash->size = sflash->blocksize * sflash->numblocks;
 	sflash->present = true;
+	sflash->poll = bcma_sflash_poll;
+	sflash->write = bcma_sflash_write;
+	sflash->erase = bcma_sflash_erase;
+	sflash->type = BCM47XX_SFLASH_BCMA;
+	sflash->bcc = cc;
 
 	bcma_info(bus, "Found %s serial flash (size: %dKiB, blocksize: 0x%X, blocks: %d)\n",
 		  e->name, sflash->size / 1024, sflash->blocksize,
--- a/include/linux/bcma/bcma_driver_chipcommon.h
+++ b/include/linux/bcma/bcma_driver_chipcommon.h
@@ -3,6 +3,7 @@
 
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/mtd/bcm47xxsflash.h>
 
 /** ChipCommon core registers. **/
 #define BCMA_CC_ID			0x0000
@@ -578,19 +579,6 @@ struct bcma_pflash {
 	u32 window_size;
 };
 
-#ifdef CONFIG_BCMA_SFLASH
-struct bcma_sflash {
-	bool present;
-	u32 window;
-	u32 blocksize;
-	u16 numblocks;
-	u32 size;
-
-	struct mtd_info *mtd;
-	void *priv;
-};
-#endif
-
 #ifdef CONFIG_BCMA_NFLASH
 struct mtd_info;
 
@@ -624,7 +612,7 @@ struct bcma_drv_cc {
 #ifdef CONFIG_BCMA_DRIVER_MIPS
 	struct bcma_pflash pflash;
 #ifdef CONFIG_BCMA_SFLASH
-	struct bcma_sflash sflash;
+	struct bcm47xxsflash sflash;
 #endif
 #ifdef CONFIG_BCMA_NFLASH
 	struct bcma_nflash nflash;