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From a62940e988526c881966a8c72cc28c95fca89f3c Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <hauke@hauke-m.de>
Date: Sun, 17 Jul 2011 14:53:07 +0200
Subject: [PATCH 13/26] bcma: add serial flash support to bcma


Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
 drivers/bcma/Kconfig                        |    5 +
 drivers/bcma/Makefile                       |    1 +
 drivers/bcma/bcma_private.h                 |    5 +
 drivers/bcma/driver_chipcommon_sflash.c     |  555 +++++++++++++++++++++++++++
 drivers/bcma/driver_mips.c                  |    8 +-
 include/linux/bcma/bcma_driver_chipcommon.h |   24 ++
 6 files changed, 597 insertions(+), 1 deletions(-)
 create mode 100644 drivers/bcma/driver_chipcommon_sflash.c

--- a/drivers/bcma/Kconfig
+++ b/drivers/bcma/Kconfig
@@ -38,6 +38,11 @@ config BCMA_HOST_SOC
 	bool
 	depends on BCMA_DRIVER_MIPS
 
+config BCMA_SFLASH
+	bool
+	depends on BCMA_DRIVER_MIPS
+	default y
+
 config BCMA_DRIVER_MIPS
 	bool "BCMA Broadcom MIPS core driver"
 	depends on BCMA && MIPS
--- a/drivers/bcma/Makefile
+++ b/drivers/bcma/Makefile
@@ -1,5 +1,6 @@
 bcma-y					+= main.o scan.o core.o sprom.o
 bcma-y					+= driver_chipcommon.o driver_chipcommon_pmu.o
+bcma-$(CONFIG_BCMA_SFLASH)		+= driver_chipcommon_sflash.o
 bcma-y					+= driver_pci.o
 bcma-$(CONFIG_BCMA_DRIVER_PCI_HOSTMODE)	+= driver_pci_host.o
 bcma-$(CONFIG_BCMA_DRIVER_MIPS)		+= driver_mips.o
--- a/drivers/bcma/bcma_private.h
+++ b/drivers/bcma/bcma_private.h
@@ -41,6 +41,11 @@ void bcma_chipco_serial_init(struct bcma
 u32 bcma_pmu_alp_clock(struct bcma_drv_cc *cc);
 u32 bcma_pmu_get_clockcpu(struct bcma_drv_cc *cc);
 
+#ifdef CONFIG_BCMA_SFLASH
+/* driver_chipcommon_sflash.c */
+int bcma_sflash_init(struct bcma_drv_cc *cc);
+#endif /* CONFIG_BCMA_SFLASH */
+
 #ifdef CONFIG_BCMA_HOST_PCI
 /* host_pci.c */
 extern int __init bcma_host_pci_init(void);
--- /dev/null
+++ b/drivers/bcma/driver_chipcommon_sflash.c
@@ -0,0 +1,555 @@
+/*
+ * Broadcom SiliconBackplane chipcommon serial flash interface
+ *
+ * Copyright 2011, Jonas Gorski <jonas.gorski@gmail.com>
+ * Copyright 2010, Broadcom Corporation
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/bcma/bcma.h>
+#include <linux/bcma/bcma_driver_chipcommon.h>
+#include <linux/delay.h>
+
+#include "bcma_private.h"
+
+#define NUM_RETRIES	3
+
+
+/* Issue a serial flash command */
+static inline void bcma_sflash_cmd(struct bcma_drv_cc *cc, u32 opcode)
+{
+	bcma_cc_write32(cc, BCMA_CC_FLASHCTL,
+			BCMA_CC_FLASHCTL_START | opcode);
+	while (bcma_cc_read32(cc, BCMA_CC_FLASHCTL) & BCMA_CC_FLASHCTL_BUSY)
+		;
+}
+
+
+static inline 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);
+}
+
+/* Initialize serial flash access */
+int bcma_sflash_init(struct bcma_drv_cc *cc)
+{
+	u32 id, id2;
+
+	memset(&cc->sflash, 0, sizeof(struct bcma_sflash));
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		/* Probe for ST chips */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_DP);
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 0);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+		cc->sflash.blocksize = 64 * 1024;
+		switch (id) {
+		case 0x11:
+			/* ST M25P20 2 Mbit Serial Flash */
+			cc->sflash.numblocks = 4;
+			break;
+		case 0x12:
+			/* ST M25P40 4 Mbit Serial Flash */
+			cc->sflash.numblocks = 8;
+			break;
+		case 0x13:
+			/* ST M25P80 8 Mbit Serial Flash */
+			cc->sflash.numblocks = 16;
+			break;
+		case 0x14:
+			/* ST M25P16 16 Mbit Serial Flash */
+			cc->sflash.numblocks = 32;
+			break;
+		case 0x15:
+			/* ST M25P32 32 Mbit Serial Flash */
+			cc->sflash.numblocks = 64;
+			break;
+		case 0x16:
+			/* ST M25P64 64 Mbit Serial Flash */
+			cc->sflash.numblocks = 128;
+			break;
+		case 0x17:
+			/* ST M25FL128 128 Mbit Serial Flash */
+			cc->sflash.numblocks = 256;
+			break;
+		case 0xbf:
+			/* All of the following flashes are SST with
+			 * 4KB subsectors. Others should be added but
+			 * We'll have to revamp the way we identify them
+			 * since RES is not eough to disambiguate them.
+			 */
+			cc->sflash.blocksize = 4 * 1024;
+			bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 1);
+			bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+			id2 = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+			switch (id2) {
+			case 1:
+				/* SST25WF512 512 Kbit Serial Flash */
+			case 0x48:
+				/* SST25VF512 512 Kbit Serial Flash */
+				cc->sflash.numblocks = 16;
+				break;
+			case 2:
+				/* SST25WF010 1 Mbit Serial Flash */
+			case 0x49:
+				/* SST25VF010 1 Mbit Serial Flash */
+				cc->sflash.numblocks = 32;
+				break;
+			case 3:
+				/* SST25WF020 2 Mbit Serial Flash */
+			case 0x43:
+				/* SST25VF020 2 Mbit Serial Flash */
+				cc->sflash.numblocks = 64;
+				break;
+			case 4:
+				/* SST25WF040 4 Mbit Serial Flash */
+			case 0x44:
+				/* SST25VF040 4 Mbit Serial Flash */
+			case 0x8d:
+				/* SST25VF040B 4 Mbit Serial Flash */
+				cc->sflash.numblocks = 128;
+				break;
+			case 5:
+				/* SST25WF080 8 Mbit Serial Flash */
+			case 0x8e:
+				/* SST25VF080B 8 Mbit Serial Flash */
+				cc->sflash.numblocks = 256;
+				break;
+			case 0x41:
+				/* SST25VF016 16 Mbit Serial Flash */
+				cc->sflash.numblocks = 512;
+				break;
+			case 0x4a:
+				/* SST25VF032 32 Mbit Serial Flash */
+				cc->sflash.numblocks = 1024;
+				break;
+			case 0x4b:
+				/* SST25VF064 64 Mbit Serial Flash */
+				cc->sflash.numblocks = 2048;
+				break;
+			}
+			break;
+		}
+		break;
+
+	case BCMA_CC_FLASHT_ATSER:
+		/* Probe for Atmel chips */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_STATUS);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA) & 0x3c;
+		switch (id) {
+		case 0xc:
+			/* Atmel AT45DB011 1Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 512;
+			break;
+		case 0x14:
+			/* Atmel AT45DB021 2Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 1024;
+			break;
+		case 0x1c:
+			/* Atmel AT45DB041 4Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 2048;
+			break;
+		case 0x24:
+			/* Atmel AT45DB081 8Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 4096;
+			break;
+		case 0x2c:
+			/* Atmel AT45DB161 16Mbit Serial Flash */
+			cc->sflash.blocksize = 512;
+			cc->sflash.numblocks = 4096;
+			break;
+		case 0x34:
+			/* Atmel AT45DB321 32Mbit Serial Flash */
+			cc->sflash.blocksize = 512;
+			cc->sflash.numblocks = 8192;
+			break;
+		case 0x3c:
+			/* Atmel AT45DB642 64Mbit Serial Flash */
+			cc->sflash.blocksize = 1024;
+			cc->sflash.numblocks = 8192;
+			break;
+		}
+		break;
+	}
+
+	cc->sflash.size = cc->sflash.blocksize * cc->sflash.numblocks;
+
+	return cc->sflash.size ? 0 : -ENODEV;
+}
+
+/* Read len bytes starting at offset into buf. Returns number of bytes read. */
+int bcma_sflash_read(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   u8 *buf)
+{
+	u8 *from, *to;
+	u32 cnt, i;
+
+	if (!len)
+		return 0;
+
+	if ((offset + len) > cc->sflash.size)
+		return -EINVAL;
+
+	if ((len >= 4) && (offset & 3))
+		cnt = 4 - (offset & 3);
+	else if ((len >= 4) && ((u32)buf & 3))
+		cnt = 4 - ((u32)buf & 3);
+	else
+		cnt = len;
+
+
+	if (cc->core->id.rev == 12)
+		from = (u8 *)KSEG1ADDR(BCMA_FLASH2 + offset);
+	else
+		from = (u8 *)KSEG0ADDR(BCMA_FLASH2 + offset);
+
+	to = (u8 *)buf;
+
+	if (cnt < 4) {
+		for (i = 0; i < cnt; i++) {
+			*to = readb(from);
+			from++;
+			to++;
+		}
+		return cnt;
+	}
+
+	while (cnt >= 4) {
+		*(u32 *)to = readl(from);
+		from += 4;
+		to += 4;
+		cnt -= 4;
+	}
+
+	return len - cnt;
+}
+
+/* Poll for command completion. Returns zero when complete. */
+int bcma_sflash_poll(struct bcma_drv_cc *cc, u32 offset)
+{
+	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 bcma_drv_cc *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct bcma_bus *bus = cc->core->bus;
+	int ret = 0;
+	bool is4712b0 = (bus->chipinfo.id == 0x4712) && (bus->chipinfo.rev == 3);
+	u32 mask;
+
+
+	/* Enable writes */
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_WREN);
+	if (is4712b0) {
+		mask = 1 << 14;
+		bcma_sflash_write_u8(cc, offset, *buf++);
+		/* Set chip select */
+		bcma_cc_set32(cc, BCMA_CC_GPIOOUT, mask);
+		/* Issue a page program with the first byte */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_PP);
+		ret = 1;
+		offset++;
+		len--;
+		while (len > 0) {
+			if ((offset & 255) == 0) {
+				/* Page boundary, drop cs and return */
+				bcma_cc_mask32(cc, BCMA_CC_GPIOOUT, ~mask);
+				udelay(1);
+				if (!bcma_sflash_poll(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				bcma_sflash_cmd(cc, *buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs */
+		bcma_cc_mask32(cc, BCMA_CC_GPIOOUT, ~mask);
+		udelay(1);
+		if (!bcma_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else if (cc->core->id.rev >= 20) {
+		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);
+		ret = 1;
+		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(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				bcma_sflash_cmd(cc,
+						BCMA_CC_FLASHCTL_ST_CSA |
+						*buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs & poll */
+		bcma_cc_write32(cc, BCMA_CC_FLASHCTL, 0);
+		udelay(1);
+		if (!bcma_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else {
+		ret = 1;
+		bcma_sflash_write_u8(cc, offset, *buf);
+		/* Page program */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_PP);
+	}
+	return ret;
+}
+
+static int sflash_at_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct bcma_sflash *sfl = &cc->sflash;
+	u32 page, byte, mask;
+	int ret = 0;
+	mask = sfl->blocksize - 1;
+	page = (offset & ~mask) << 1;
+	byte = offset & mask;
+	/* Read main memory page into buffer 1 */
+	if (byte || (len < sfl->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(cc, offset)) {
+			udelay(10);
+			i--;
+		}
+		BUG_ON(!bcma_sflash_poll(cc, offset));
+	}
+	/* Write into buffer 1 */
+	for (ret = 0; (ret < (int)len) && (byte < sfl->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.
+ */
+int bcma_sflash_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			    const u8 *buf)
+{
+	struct bcma_sflash *sfl;
+	int ret = 0, tries = NUM_RETRIES;
+
+	if (!len)
+		return 0;
+
+	if ((offset + len) > cc->sflash.size)
+		return -EINVAL;
+
+	sfl = &cc->sflash;
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		do {
+			ret = sflash_st_write(cc, offset, len, buf);
+			tries--;
+		} while (ret == -EAGAIN && tries > 0);
+
+		if (ret == -EAGAIN && tries == 0) {
+			pr_info("ST Flash rejected write\n");
+			ret = -EIO;
+		}
+		break;
+	case BCMA_CC_FLASHT_ATSER:
+		ret = sflash_at_write(cc, offset, len, buf);
+		break;
+	}
+
+	return ret;
+}
+
+/* Erase a region. Returns number of bytes scheduled for erasure.
+ * Caller should poll for completion.
+ */
+int bcma_sflash_erase(struct bcma_drv_cc *cc, u32 offset)
+{
+	struct bcma_sflash *sfl;
+
+	if (offset >= cc->sflash.size)
+		return -EINVAL;
+
+	sfl = &cc->sflash;
+	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.
+		 */
+		bcma_sflash_cmd(cc, (sfl->blocksize < (64 * 1024)) ? BCMA_CC_FLASHCTL_ST_SSE : BCMA_CC_FLASHCTL_ST_SE);
+		return sfl->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 sfl->blocksize;
+	}
+
+	return 0;
+}
+
+/*
+ * writes the appropriate range of flash, a NULL buf simply erases
+ * the region of flash
+ */
+int bcma_sflash_commit(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			     const u8 *buf)
+{
+	struct bcma_sflash *sfl;
+	u8 *block = NULL, *cur_ptr, *blk_ptr;
+	u32 blocksize = 0, mask, cur_offset, cur_length, cur_retlen, remainder;
+	u32 blk_offset, blk_len, copied;
+	int bytes, ret = 0;
+
+	/* Check address range */
+	if (len <= 0)
+		return 0;
+
+	sfl = &cc->sflash;
+	if ((offset + len) > sfl->size)
+		return -EINVAL;
+
+	blocksize = sfl->blocksize;
+	mask = blocksize - 1;
+
+	/* Allocate a block of mem */
+	block = kmalloc(blocksize, GFP_KERNEL);
+	if (!block)
+		return -ENOMEM;
+
+	while (len) {
+		/* Align offset */
+		cur_offset = offset & ~mask;
+		cur_length = blocksize;
+		cur_ptr = block;
+
+		remainder = blocksize - (offset & mask);
+		if (len < remainder)
+			cur_retlen = len;
+		else
+			cur_retlen = remainder;
+
+		/* buf == NULL means erase only */
+		if (buf) {
+			/* Copy existing data into holding block if necessary */
+			if ((offset & mask) || (len < blocksize)) {
+				blk_offset = cur_offset;
+				blk_len = cur_length;
+				blk_ptr = cur_ptr;
+
+				/* Copy entire block */
+				while (blk_len) {
+					copied = bcma_sflash_read(cc,
+							blk_offset,
+							blk_len, blk_ptr);
+					blk_offset += copied;
+					blk_len -= copied;
+					blk_ptr += copied;
+				}
+			}
+
+			/* Copy input data into holding block */
+			memcpy(cur_ptr + (offset & mask), buf, cur_retlen);
+		}
+
+		/* Erase block */
+		ret = bcma_sflash_erase(cc, cur_offset);
+		if (ret < 0)
+			goto done;
+
+		while (bcma_sflash_poll(cc, cur_offset));
+
+		/* buf == NULL means erase only */
+		if (!buf) {
+			offset += cur_retlen;
+			len -= cur_retlen;
+			continue;
+		}
+
+		/* Write holding block */
+		while (cur_length > 0) {
+			bytes = bcma_sflash_write(cc, cur_offset,
+					cur_length, cur_ptr);
+
+			if (bytes < 0) {
+				ret = bytes;
+				goto done;
+			}
+
+			while (bcma_sflash_poll(cc, cur_offset))
+				;
+
+			cur_offset += bytes;
+			cur_length -= bytes;
+			cur_ptr += bytes;
+		}
+
+		offset += cur_retlen;
+		len -= cur_retlen;
+		buf += cur_retlen;
+	}
+
+	ret = len;
+done:
+	kfree(block);
+	return ret;
+}
--- a/drivers/bcma/driver_mips.c
+++ b/drivers/bcma/driver_mips.c
@@ -185,7 +185,13 @@ static void bcma_core_mips_flash_detect(
 	switch (bus->drv_cc.capabilities & BCMA_CC_CAP_FLASHT) {
 	case BCMA_CC_FLASHT_STSER:
 	case BCMA_CC_FLASHT_ATSER:
-		pr_err("Serial flash not supported.\n");
+#ifdef CONFIG_BCMA_SFLASH
+		pr_info("found serial flash.\n");
+		bus->drv_cc.flash_type = BCMA_SFLASH;
+		bcma_sflash_init(&bus->drv_cc);
+#else
+		pr_info("serial flash not supported.\n");
+#endif /* CONFIG_BCMA_SFLASH */
 		break;
 	case BCMA_CC_FLASHT_PARA:
 		pr_info("found parallel flash.\n");
--- a/include/linux/bcma/bcma_driver_chipcommon.h
+++ b/include/linux/bcma/bcma_driver_chipcommon.h
@@ -375,6 +375,7 @@ struct bcma_chipcommon_pmu {
 #ifdef CONFIG_BCMA_DRIVER_MIPS
 enum bcma_flash_type {
 	BCMA_PFLASH,
+	BCMA_SFLASH,
 };
 
 struct bcma_pflash {
@@ -383,6 +384,14 @@ struct bcma_pflash {
 	u32 window_size;
 };
 
+#ifdef CONFIG_BCMA_SFLASH
+struct bcma_sflash {
+	u32 blocksize;		/* Block size */
+	u32 numblocks;		/* Number of blocks */
+	u32 size;		/* Total size in bytes */
+};
+#endif /* CONFIG_BCMA_SFLASH */
+
 struct bcma_serial_port {
 	void *regs;
 	unsigned long clockspeed;
@@ -405,6 +414,9 @@ struct bcma_drv_cc {
 	enum bcma_flash_type flash_type;
 	union {
 		struct bcma_pflash pflash;
+#ifdef CONFIG_BCMA_SFLASH
+		struct bcma_sflash sflash;
+#endif /* CONFIG_BCMA_SFLASH */
 	};
 
 	int nr_serial_ports;
@@ -459,4 +471,16 @@ extern void bcma_chipco_chipctl_maskset(
 extern void bcma_chipco_regctl_maskset(struct bcma_drv_cc *cc,
 				       u32 offset, u32 mask, u32 set);
 
+#ifdef CONFIG_BCMA_SFLASH
+/* Chipcommon sflash support. */
+int bcma_sflash_read(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   u8 *buf);
+int bcma_sflash_poll(struct bcma_drv_cc *cc, u32 offset);
+int bcma_sflash_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			    const u8 *buf);
+int bcma_sflash_erase(struct bcma_drv_cc *cc, u32 offset);
+int bcma_sflash_commit(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			     const u8 *buf);
+#endif /* CONFIG_BCMA_SFLASH */
+
 #endif /* LINUX_BCMA_DRIVER_CC_H_ */