--- a/drivers/ssb/Kconfig
+++ b/drivers/ssb/Kconfig
@@ -137,6 +137,12 @@ config SSB_DRIVER_MIPS
 
 	  If unsure, say N
 
+config SSB_SFLASH
+	bool
+	depends on SSB_DRIVER_MIPS
+	default y
+
+
 # Assumption: We are on embedded, if we compile the MIPS core.
 config SSB_EMBEDDED
 	bool
--- a/drivers/ssb/Makefile
+++ b/drivers/ssb/Makefile
@@ -11,6 +11,7 @@ ssb-$(CONFIG_SSB_SDIOHOST)		+= sdio.o
 # built-in drivers
 ssb-y					+= driver_chipcommon.o
 ssb-y					+= driver_chipcommon_pmu.o
+ssb-$(CONFIG_SSB_SFLASH)		+= driver_chipcommon_sflash.o
 ssb-$(CONFIG_SSB_DRIVER_MIPS)		+= driver_mipscore.o
 ssb-$(CONFIG_SSB_DRIVER_EXTIF)		+= driver_extif.o
 ssb-$(CONFIG_SSB_DRIVER_PCICORE)	+= driver_pcicore.o
--- /dev/null
+++ b/drivers/ssb/driver_chipcommon_sflash.c
@@ -0,0 +1,451 @@
+/*
+ * Broadcom SiliconBackplane 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.
+ */
+
+#include <linux/ssb/ssb.h>
+#include <linux/ssb/ssb_driver_chipcommon.h>
+#include <linux/delay.h>
+
+#include "ssb_private.h"
+
+#define NUM_RETRIES	3
+
+
+/* Issue a serial flash command */
+static inline void ssb_sflash_cmd(struct ssb_chipcommon *cc, u32 opcode)
+{
+	chipco_write32(cc, SSB_CHIPCO_FLASHCTL,
+			SSB_CHIPCO_FLASHCTL_START | opcode);
+	while (chipco_read32(cc, SSB_CHIPCO_FLASHCTL)
+			& SSB_CHIPCO_FLASHCTL_BUSY)
+		;
+}
+
+
+static inline void ssb_sflash_write_u8(struct ssb_chipcommon *cc,
+				       u32 offset, u8 byte)
+{
+	chipco_write32(cc, SSB_CHIPCO_FLASHADDR, offset);
+	chipco_write32(cc, SSB_CHIPCO_FLASHDATA, byte);
+}
+
+/* Initialize serial flash access */
+int ssb_sflash_init(struct ssb_chipcommon *cc)
+{
+	u32 id, id2;
+
+	memset(&cc->sflash, 0, sizeof(struct ssb_sflash));
+
+	switch (cc->capabilities & SSB_CHIPCO_CAP_FLASHT) {
+	case SSB_CHIPCO_FLASHT_STSER:
+		/* Probe for ST chips */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_DP);
+		chipco_write32(cc, SSB_CHIPCO_FLASHADDR, 0);
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_RES);
+		id = chipco_read32(cc, SSB_CHIPCO_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;
+			chipco_write32(cc, SSB_CHIPCO_FLASHADDR, 1);
+			ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_RES);
+			id2 = chipco_read32(cc, SSB_CHIPCO_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 SSB_CHIPCO_FLASHT_ATSER:
+		/* Probe for Atmel chips */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_AT_STATUS);
+		id = chipco_read32(cc, SSB_CHIPCO_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 ssb_sflash_read(struct ssb_chipcommon *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->dev->id.revision == 12)
+		from = (u8 *)KSEG1ADDR(SSB_FLASH2 + offset);
+	else
+		from = (u8 *)KSEG0ADDR(SSB_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 ssb_sflash_poll(struct ssb_chipcommon *cc, u32 offset)
+{
+	if (offset >= cc->sflash.size)
+		return -22;
+
+	switch (cc->capabilities & SSB_CHIPCO_CAP_FLASHT) {
+	case SSB_CHIPCO_FLASHT_STSER:
+		/* Check for ST Write In Progress bit */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_RDSR);
+		return chipco_read32(cc, SSB_CHIPCO_FLASHDATA)
+				& SSB_CHIPCO_FLASHSTA_ST_WIP;
+	case SSB_CHIPCO_FLASHT_ATSER:
+		/* Check for Atmel Ready bit */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_AT_STATUS);
+		return !(chipco_read32(cc, SSB_CHIPCO_FLASHDATA)
+				& SSB_CHIPCO_FLASHSTA_AT_READY);
+	}
+
+	return 0;
+}
+
+
+static int sflash_st_write(struct ssb_chipcommon *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct ssb_bus *bus = cc->dev->bus;
+	int ret = 0;
+	bool is4712b0 = (bus->chip_id == 0x4712) && (bus->chip_rev == 3);
+	u32 mask;
+
+	/* Enable writes */
+	ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_WREN);
+	if (is4712b0) {
+		mask = 1 << 14;
+		ssb_sflash_write_u8(cc, offset, *buf++);
+		/* Set chip select */
+		chipco_set32(cc, SSB_CHIPCO_GPIOOUT, mask);
+		/* Issue a page program with the first byte */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_PP);
+		ret = 1;
+		offset++;
+		len--;
+		while (len > 0) {
+			if ((offset & 255) == 0) {
+				/* Page boundary, drop cs and return */
+				chipco_mask32(cc, SSB_CHIPCO_GPIOOUT, ~mask);
+				udelay(1);
+				if (!ssb_sflash_poll(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				ssb_sflash_cmd(cc, *buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs */
+		chipco_mask32(cc, SSB_CHIPCO_GPIOOUT, ~mask);
+		udelay(1);
+		if (!ssb_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else if (cc->dev->id.revision >= 20) {
+		ssb_sflash_write_u8(cc, offset, *buf++);
+		/* Issue a page program with CSA bit set */
+		ssb_sflash_cmd(cc,
+				SSB_CHIPCO_FLASHCTL_ST_CSA |
+				SSB_CHIPCO_FLASHCTL_ST_PP);
+		ret = 1;
+		offset++;
+		len--;
+		while (len > 0) {
+			if ((offset & 255) == 0) {
+				/* Page boundary, poll droping cs and return */
+				chipco_write32(cc, SSB_CHIPCO_FLASHCTL, 0);
+				udelay(1);
+				if (!ssb_sflash_poll(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				ssb_sflash_cmd(cc,
+						SSB_CHIPCO_FLASHCTL_ST_CSA |
+						*buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs & poll */
+		chipco_write32(cc, SSB_CHIPCO_FLASHCTL, 0);
+		udelay(1);
+		if (!ssb_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else {
+		ret = 1;
+		ssb_sflash_write_u8(cc, offset, *buf);
+		/* Page program */
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_PP);
+	}
+	return ret;
+}
+
+static int sflash_at_write(struct ssb_chipcommon *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct ssb_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;
+		chipco_write32(cc, SSB_CHIPCO_FLASHADDR, page);
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_AT_BUF1_LOAD);
+		/* 250 us for AT45DB321B */
+		while (i > 0 && ssb_sflash_poll(cc, offset)) {
+			udelay(10);
+			i--;
+		}
+		BUG_ON(!ssb_sflash_poll(cc, offset));
+	}
+	/* Write into buffer 1 */
+	for (ret = 0; (ret < (int)len) && (byte < sfl->blocksize); ret++) {
+		ssb_sflash_write_u8(cc, byte++, *buf++);
+		ssb_sflash_cmd(cc,
+				SSB_CHIPCO_FLASHCTL_AT_BUF1_WRITE);
+	}
+	/* Write buffer 1 into main memory page */
+	chipco_write32(cc, SSB_CHIPCO_FLASHADDR, page);
+	ssb_sflash_cmd(cc, SSB_CHIPCO_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 ssb_sflash_write(struct ssb_chipcommon *cc, u32 offset, u32 len,
+			    const u8 *buf)
+{
+	struct ssb_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 & SSB_CHIPCO_CAP_FLASHT) {
+	case SSB_CHIPCO_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 SSB_CHIPCO_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 ssb_sflash_erase(struct ssb_chipcommon *cc, u32 offset)
+{
+	struct ssb_sflash *sfl;
+
+	if (offset >= cc->sflash.size)
+		return -EINVAL;
+
+	sfl = &cc->sflash;
+	switch (cc->capabilities & SSB_CHIPCO_CAP_FLASHT) {
+	case SSB_CHIPCO_FLASHT_STSER:
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_WREN);
+		chipco_write32(cc, SSB_CHIPCO_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 (sfl->blocksize < (64 * 1024))
+			ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_SSE);
+		else
+			ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_SE);
+		return sfl->blocksize;
+	case SSB_CHIPCO_FLASHT_ATSER:
+		chipco_write32(cc, SSB_CHIPCO_FLASHADDR, offset << 1);
+		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_AT_PAGE_ERASE);
+		return sfl->blocksize;
+	}
+
+	return 0;
+}
--- a/drivers/ssb/driver_mipscore.c
+++ b/drivers/ssb/driver_mipscore.c
@@ -203,7 +203,13 @@ static void ssb_mips_flash_detect(struct
 	switch (bus->chipco.capabilities & SSB_CHIPCO_CAP_FLASHT) {
 	case SSB_CHIPCO_FLASHT_STSER:
 	case SSB_CHIPCO_FLASHT_ATSER:
+#ifdef CONFIG_SSB_SFLASH
+		pr_info("found serial flash.\n");
+		bus->chipco.flash_type = SSB_SFLASH;
+		ssb_sflash_init(&bus->chipco);
+#else
 		pr_info("serial flash not supported.\n");
+#endif /* CONFIG_SSB_SFLASH */
 		break;
 	case SSB_CHIPCO_FLASHT_PARA:
 		pr_info("found parallel flash.\n");
--- a/drivers/ssb/ssb_private.h
+++ b/drivers/ssb/ssb_private.h
@@ -192,6 +192,10 @@ extern int ssb_devices_freeze(struct ssb
 extern int ssb_devices_thaw(struct ssb_freeze_context *ctx);
 
 
+#ifdef CONFIG_SSB_SFLASH
+/* driver_chipcommon_sflash.c */
+int ssb_sflash_init(struct ssb_chipcommon *cc);
+#endif /* CONFIG_SSB_SFLASH */
 
 /* b43_pci_bridge.c */
 #ifdef CONFIG_SSB_B43_PCI_BRIDGE
--- a/include/linux/ssb/ssb_driver_chipcommon.h
+++ b/include/linux/ssb/ssb_driver_chipcommon.h
@@ -503,8 +503,10 @@
 #define SSB_CHIPCO_FLASHCTL_ST_PP	0x0302		/* Page Program */
 #define SSB_CHIPCO_FLASHCTL_ST_SE	0x02D8		/* Sector Erase */
 #define SSB_CHIPCO_FLASHCTL_ST_BE	0x00C7		/* Bulk Erase */
-#define SSB_CHIPCO_FLASHCTL_ST_DP	0x00B9		/* Deep Power-down */
-#define SSB_CHIPCO_FLASHCTL_ST_RSIG	0x03AB		/* Read Electronic Signature */
+#define SSB_CHIPCO_FLASHCTL_ST_DP	0x00D9		/* Deep Power-down */
+#define SSB_CHIPCO_FLASHCTL_ST_RES	0x03AB		/* Read Electronic Signature */
+#define SSB_CHIPCO_FLASHCTL_ST_CSA	0x1000		/* Keep chip select asserted */
+#define SSB_CHIPCO_FLASHCTL_ST_SSE	0x0220		/* Sub-sector Erase */
 
 /* Status register bits for ST flashes */
 #define SSB_CHIPCO_FLASHSTA_ST_WIP	0x01		/* Write In Progress */
@@ -585,6 +587,7 @@ struct ssb_chipcommon_pmu {
 #ifdef CONFIG_SSB_DRIVER_MIPS
 enum ssb_flash_type {
 	SSB_PFLASH,
+	SSB_SFLASH,
 };
 
 struct ssb_pflash {
@@ -592,6 +595,14 @@ struct ssb_pflash {
 	u32 window;
 	u32 window_size;
 };
+
+#ifdef CONFIG_SSB_SFLASH
+struct ssb_sflash {
+	u32 blocksize;		/* Block size */
+	u32 numblocks;		/* Number of blocks */
+	u32 size;		/* Total size in bytes */
+};
+#endif /* CONFIG_SSB_SFLASH */
 #endif /* CONFIG_SSB_DRIVER_MIPS */
 
 struct ssb_chipcommon {
@@ -605,6 +616,9 @@ struct ssb_chipcommon {
 	enum ssb_flash_type flash_type;
 	union {
 		struct ssb_pflash pflash;
+#ifdef CONFIG_SSB_SFLASH
+		struct ssb_sflash sflash;
+#endif /* CONFIG_SSB_SFLASH */
 	};
 #endif /* CONFIG_SSB_DRIVER_MIPS */
 };
@@ -666,6 +680,16 @@ extern int ssb_chipco_serial_init(struct
 				  struct ssb_serial_port *ports);
 #endif /* CONFIG_SSB_SERIAL */
 
+#ifdef CONFIG_SSB_SFLASH
+/* Chipcommon sflash support. */
+int ssb_sflash_read(struct ssb_chipcommon *cc, u32 offset, u32 len,
+			   u8 *buf);
+int ssb_sflash_poll(struct ssb_chipcommon *cc, u32 offset);
+int ssb_sflash_write(struct ssb_chipcommon *cc, u32 offset, u32 len,
+			    const u8 *buf);
+int ssb_sflash_erase(struct ssb_chipcommon *cc, u32 offset);
+#endif /* CONFIG_SSB_SFLASH */
+
 /* PMU support */
 extern void ssb_pmu_init(struct ssb_chipcommon *cc);