Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3109 insertions, 0 deletions

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
new file mode 100644
index 000000000..9bd65f3f8
--- /dev/null
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -0,0 +1,3109 @@
+/*
+ * Common Flash Interface support:
+ *   AMD & Fujitsu Standard Vendor Command Set (ID 0x0002)
+ *
+ * Copyright (C) 2000 Crossnet Co. <info@crossnet.co.jp>
+ * Copyright (C) 2004 Arcom Control Systems Ltd <linux@arcom.com>
+ * Copyright (C) 2005 MontaVista Software Inc. <source@mvista.com>
+ *
+ * 2_by_8 routines added by Simon Munton
+ *
+ * 4_by_16 work by Carolyn J. Smith
+ *
+ * XIP support hooks by Vitaly Wool (based on code for Intel flash
+ * by Nicolas Pitre)
+ *
+ * 25/09/2008 Christopher Moore: TopBottom fixup for many Macronix with CFI V1.0
+ *
+ * Occasionally maintained by Thayne Harbaugh tharbaugh at lnxi dot com
+ *
+ * This code is GPL
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <asm/io.h>
+#include <asm/byteorder.h>
+
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/reboot.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/cfi.h>
+#include <linux/mtd/xip.h>
+
+#define AMD_BOOTLOC_BUG
+#define FORCE_WORD_WRITE 0
+
+#define MAX_RETRIES 3
+
+#define SST49LF004B		0x0060
+#define SST49LF040B		0x0050
+#define SST49LF008A		0x005a
+#define AT49BV6416		0x00d6
+
+/*
+ * Status Register bit description. Used by flash devices that don't
+ * support DQ polling (e.g. HyperFlash)
+ */
+#define CFI_SR_DRB		BIT(7)
+#define CFI_SR_ESB		BIT(5)
+#define CFI_SR_PSB		BIT(4)
+#define CFI_SR_WBASB		BIT(3)
+#define CFI_SR_SLSB		BIT(1)
+
+enum cfi_quirks {
+	CFI_QUIRK_DQ_TRUE_DATA = BIT(0),
+};
+
+static int cfi_amdstd_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
+static int cfi_amdstd_write_words(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
+#if !FORCE_WORD_WRITE
+static int cfi_amdstd_write_buffers(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
+#endif
+static int cfi_amdstd_erase_chip(struct mtd_info *, struct erase_info *);
+static int cfi_amdstd_erase_varsize(struct mtd_info *, struct erase_info *);
+static void cfi_amdstd_sync (struct mtd_info *);
+static int cfi_amdstd_suspend (struct mtd_info *);
+static void cfi_amdstd_resume (struct mtd_info *);
+static int cfi_amdstd_reboot(struct notifier_block *, unsigned long, void *);
+static int cfi_amdstd_get_fact_prot_info(struct mtd_info *, size_t,
+					 size_t *, struct otp_info *);
+static int cfi_amdstd_get_user_prot_info(struct mtd_info *, size_t,
+					 size_t *, struct otp_info *);
+static int cfi_amdstd_secsi_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
+static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *, loff_t, size_t,
+					 size_t *, u_char *);
+static int cfi_amdstd_read_user_prot_reg(struct mtd_info *, loff_t, size_t,
+					 size_t *, u_char *);
+static int cfi_amdstd_write_user_prot_reg(struct mtd_info *, loff_t, size_t,
+					  size_t *, u_char *);
+static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *, loff_t, size_t);
+
+static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
+				  size_t *retlen, const u_char *buf);
+
+static void cfi_amdstd_destroy(struct mtd_info *);
+
+struct mtd_info *cfi_cmdset_0002(struct map_info *, int);
+static struct mtd_info *cfi_amdstd_setup (struct mtd_info *);
+
+static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode);
+static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr);
+#include "fwh_lock.h"
+
+static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+
+static int cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+static int cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+static int cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
+
+static struct mtd_chip_driver cfi_amdstd_chipdrv = {
+	.probe		= NULL, /* Not usable directly */
+	.destroy	= cfi_amdstd_destroy,
+	.name		= "cfi_cmdset_0002",
+	.module		= THIS_MODULE
+};
+
+/*
+ * Use status register to poll for Erase/write completion when DQ is not
+ * supported. This is indicated by Bit[1:0] of SoftwareFeatures field in
+ * CFI Primary Vendor-Specific Extended Query table 1.5
+ */
+static int cfi_use_status_reg(struct cfi_private *cfi)
+{
+	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
+	u8 poll_mask = CFI_POLL_STATUS_REG | CFI_POLL_DQ;
+
+	return extp && extp->MinorVersion >= '5' &&
+		(extp->SoftwareFeatures & poll_mask) == CFI_POLL_STATUS_REG;
+}
+
+static int cfi_check_err_status(struct map_info *map, struct flchip *chip,
+				unsigned long adr)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	map_word status;
+
+	if (!cfi_use_status_reg(cfi))
+		return 0;
+
+	cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	status = map_read(map, adr);
+
+	/* The error bits are invalid while the chip's busy */
+	if (!map_word_bitsset(map, status, CMD(CFI_SR_DRB)))
+		return 0;
+
+	if (map_word_bitsset(map, status, CMD(0x3a))) {
+		unsigned long chipstatus = MERGESTATUS(status);
+
+		if (chipstatus & CFI_SR_ESB)
+			pr_err("%s erase operation failed, status %lx\n",
+			       map->name, chipstatus);
+		if (chipstatus & CFI_SR_PSB)
+			pr_err("%s program operation failed, status %lx\n",
+			       map->name, chipstatus);
+		if (chipstatus & CFI_SR_WBASB)
+			pr_err("%s buffer program command aborted, status %lx\n",
+			       map->name, chipstatus);
+		if (chipstatus & CFI_SR_SLSB)
+			pr_err("%s sector write protected, status %lx\n",
+			       map->name, chipstatus);
+
+		/* Erase/Program status bits are set on the operation failure */
+		if (chipstatus & (CFI_SR_ESB | CFI_SR_PSB))
+			return 1;
+	}
+	return 0;
+}
+
+/* #define DEBUG_CFI_FEATURES */
+
+
+#ifdef DEBUG_CFI_FEATURES
+static void cfi_tell_features(struct cfi_pri_amdstd *extp)
+{
+	const char* erase_suspend[3] = {
+		"Not supported", "Read only", "Read/write"
+	};
+	const char* top_bottom[6] = {
+		"No WP", "8x8KiB sectors at top & bottom, no WP",
+		"Bottom boot", "Top boot",
+		"Uniform, Bottom WP", "Uniform, Top WP"
+	};
+
+	printk("  Silicon revision: %d\n", extp->SiliconRevision >> 1);
+	printk("  Address sensitive unlock: %s\n",
+	       (extp->SiliconRevision & 1) ? "Not required" : "Required");
+
+	if (extp->EraseSuspend < ARRAY_SIZE(erase_suspend))
+		printk("  Erase Suspend: %s\n", erase_suspend[extp->EraseSuspend]);
+	else
+		printk("  Erase Suspend: Unknown value %d\n", extp->EraseSuspend);
+
+	if (extp->BlkProt == 0)
+		printk("  Block protection: Not supported\n");
+	else
+		printk("  Block protection: %d sectors per group\n", extp->BlkProt);
+
+
+	printk("  Temporary block unprotect: %s\n",
+	       extp->TmpBlkUnprotect ? "Supported" : "Not supported");
+	printk("  Block protect/unprotect scheme: %d\n", extp->BlkProtUnprot);
+	printk("  Number of simultaneous operations: %d\n", extp->SimultaneousOps);
+	printk("  Burst mode: %s\n",
+	       extp->BurstMode ? "Supported" : "Not supported");
+	if (extp->PageMode == 0)
+		printk("  Page mode: Not supported\n");
+	else
+		printk("  Page mode: %d word page\n", extp->PageMode << 2);
+
+	printk("  Vpp Supply Minimum Program/Erase Voltage: %d.%d V\n",
+	       extp->VppMin >> 4, extp->VppMin & 0xf);
+	printk("  Vpp Supply Maximum Program/Erase Voltage: %d.%d V\n",
+	       extp->VppMax >> 4, extp->VppMax & 0xf);
+
+	if (extp->TopBottom < ARRAY_SIZE(top_bottom))
+		printk("  Top/Bottom Boot Block: %s\n", top_bottom[extp->TopBottom]);
+	else
+		printk("  Top/Bottom Boot Block: Unknown value %d\n", extp->TopBottom);
+}
+#endif
+
+#ifdef AMD_BOOTLOC_BUG
+/* Wheee. Bring me the head of someone at AMD. */
+static void fixup_amd_bootblock(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
+	__u8 major = extp->MajorVersion;
+	__u8 minor = extp->MinorVersion;
+
+	if (((major << 8) | minor) < 0x3131) {
+		/* CFI version 1.0 => don't trust bootloc */
+
+		pr_debug("%s: JEDEC Vendor ID is 0x%02X Device ID is 0x%02X\n",
+			map->name, cfi->mfr, cfi->id);
+
+		/* AFAICS all 29LV400 with a bottom boot block have a device ID
+		 * of 0x22BA in 16-bit mode and 0xBA in 8-bit mode.
+		 * These were badly detected as they have the 0x80 bit set
+		 * so treat them as a special case.
+		 */
+		if (((cfi->id == 0xBA) || (cfi->id == 0x22BA)) &&
+
+			/* Macronix added CFI to their 2nd generation
+			 * MX29LV400C B/T but AFAICS no other 29LV400 (AMD,
+			 * Fujitsu, Spansion, EON, ESI and older Macronix)
+			 * has CFI.
+			 *
+			 * Therefore also check the manufacturer.
+			 * This reduces the risk of false detection due to
+			 * the 8-bit device ID.
+			 */
+			(cfi->mfr == CFI_MFR_MACRONIX)) {
+			pr_debug("%s: Macronix MX29LV400C with bottom boot block"
+				" detected\n", map->name);
+			extp->TopBottom = 2;	/* bottom boot */
+		} else
+		if (cfi->id & 0x80) {
+			printk(KERN_WARNING "%s: JEDEC Device ID is 0x%02X. Assuming broken CFI table.\n", map->name, cfi->id);
+			extp->TopBottom = 3;	/* top boot */
+		} else {
+			extp->TopBottom = 2;	/* bottom boot */
+		}
+
+		pr_debug("%s: AMD CFI PRI V%c.%c has no boot block field;"
+			" deduced %s from Device ID\n", map->name, major, minor,
+			extp->TopBottom == 2 ? "bottom" : "top");
+	}
+}
+#endif
+
+#if !FORCE_WORD_WRITE
+static void fixup_use_write_buffers(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	if (cfi->cfiq->BufWriteTimeoutTyp) {
+		pr_debug("Using buffer write method\n");
+		mtd->_write = cfi_amdstd_write_buffers;
+	}
+}
+#endif /* !FORCE_WORD_WRITE */
+
+/* Atmel chips don't use the same PRI format as AMD chips */
+static void fixup_convert_atmel_pri(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
+	struct cfi_pri_atmel atmel_pri;
+
+	memcpy(&atmel_pri, extp, sizeof(atmel_pri));
+	memset((char *)extp + 5, 0, sizeof(*extp) - 5);
+
+	if (atmel_pri.Features & 0x02)
+		extp->EraseSuspend = 2;
+
+	/* Some chips got it backwards... */
+	if (cfi->id == AT49BV6416) {
+		if (atmel_pri.BottomBoot)
+			extp->TopBottom = 3;
+		else
+			extp->TopBottom = 2;
+	} else {
+		if (atmel_pri.BottomBoot)
+			extp->TopBottom = 2;
+		else
+			extp->TopBottom = 3;
+	}
+
+	/* burst write mode not supported */
+	cfi->cfiq->BufWriteTimeoutTyp = 0;
+	cfi->cfiq->BufWriteTimeoutMax = 0;
+}
+
+static void fixup_use_secsi(struct mtd_info *mtd)
+{
+	/* Setup for chips with a secsi area */
+	mtd->_read_user_prot_reg = cfi_amdstd_secsi_read;
+	mtd->_read_fact_prot_reg = cfi_amdstd_secsi_read;
+}
+
+static void fixup_use_erase_chip(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	if ((cfi->cfiq->NumEraseRegions == 1) &&
+		((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0)) {
+		mtd->_erase = cfi_amdstd_erase_chip;
+	}
+
+}
+
+/*
+ * Some Atmel chips (e.g. the AT49BV6416) power-up with all sectors
+ * locked by default.
+ */
+static void fixup_use_atmel_lock(struct mtd_info *mtd)
+{
+	mtd->_lock = cfi_atmel_lock;
+	mtd->_unlock = cfi_atmel_unlock;
+	mtd->flags |= MTD_POWERUP_LOCK;
+}
+
+static void fixup_old_sst_eraseregion(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	/*
+	 * These flashes report two separate eraseblock regions based on the
+	 * sector_erase-size and block_erase-size, although they both operate on the
+	 * same memory. This is not allowed according to CFI, so we just pick the
+	 * sector_erase-size.
+	 */
+	cfi->cfiq->NumEraseRegions = 1;
+}
+
+static void fixup_sst39vf(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	fixup_old_sst_eraseregion(mtd);
+
+	cfi->addr_unlock1 = 0x5555;
+	cfi->addr_unlock2 = 0x2AAA;
+}
+
+static void fixup_sst39vf_rev_b(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	fixup_old_sst_eraseregion(mtd);
+
+	cfi->addr_unlock1 = 0x555;
+	cfi->addr_unlock2 = 0x2AA;
+
+	cfi->sector_erase_cmd = CMD(0x50);
+}
+
+static void fixup_sst38vf640x_sectorsize(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	fixup_sst39vf_rev_b(mtd);
+
+	/*
+	 * CFI reports 1024 sectors (0x03ff+1) of 64KBytes (0x0100*256) where
+	 * it should report a size of 8KBytes (0x0020*256).
+	 */
+	cfi->cfiq->EraseRegionInfo[0] = 0x002003ff;
+	pr_warn("%s: Bad 38VF640x CFI data; adjusting sector size from 64 to 8KiB\n",
+		mtd->name);
+}
+
+static void fixup_s29gl064n_sectors(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	if ((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0x003f) {
+		cfi->cfiq->EraseRegionInfo[0] |= 0x0040;
+		pr_warn("%s: Bad S29GL064N CFI data; adjust from 64 to 128 sectors\n",
+			mtd->name);
+	}
+}
+
+static void fixup_s29gl032n_sectors(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	if ((cfi->cfiq->EraseRegionInfo[1] & 0xffff) == 0x007e) {
+		cfi->cfiq->EraseRegionInfo[1] &= ~0x0040;
+		pr_warn("%s: Bad S29GL032N CFI data; adjust from 127 to 63 sectors\n",
+			mtd->name);
+	}
+}
+
+static void fixup_s29ns512p_sectors(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	/*
+	 *  S29NS512P flash uses more than 8bits to report number of sectors,
+	 * which is not permitted by CFI.
+	 */
+	cfi->cfiq->EraseRegionInfo[0] = 0x020001ff;
+	pr_warn("%s: Bad S29NS512P CFI data; adjust to 512 sectors\n",
+		mtd->name);
+}
+
+static void fixup_quirks(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	if (cfi->mfr == CFI_MFR_AMD && cfi->id == 0x0c01)
+		cfi->quirks |= CFI_QUIRK_DQ_TRUE_DATA;
+}
+
+/* Used to fix CFI-Tables of chips without Extended Query Tables */
+static struct cfi_fixup cfi_nopri_fixup_table[] = {
+	{ CFI_MFR_SST, 0x234a, fixup_sst39vf }, /* SST39VF1602 */
+	{ CFI_MFR_SST, 0x234b, fixup_sst39vf }, /* SST39VF1601 */
+	{ CFI_MFR_SST, 0x235a, fixup_sst39vf }, /* SST39VF3202 */
+	{ CFI_MFR_SST, 0x235b, fixup_sst39vf }, /* SST39VF3201 */
+	{ CFI_MFR_SST, 0x235c, fixup_sst39vf_rev_b }, /* SST39VF3202B */
+	{ CFI_MFR_SST, 0x235d, fixup_sst39vf_rev_b }, /* SST39VF3201B */
+	{ CFI_MFR_SST, 0x236c, fixup_sst39vf_rev_b }, /* SST39VF6402B */
+	{ CFI_MFR_SST, 0x236d, fixup_sst39vf_rev_b }, /* SST39VF6401B */
+	{ 0, 0, NULL }
+};
+
+static struct cfi_fixup cfi_fixup_table[] = {
+	{ CFI_MFR_ATMEL, CFI_ID_ANY, fixup_convert_atmel_pri },
+#ifdef AMD_BOOTLOC_BUG
+	{ CFI_MFR_AMD, CFI_ID_ANY, fixup_amd_bootblock },
+	{ CFI_MFR_AMIC, CFI_ID_ANY, fixup_amd_bootblock },
+	{ CFI_MFR_MACRONIX, CFI_ID_ANY, fixup_amd_bootblock },
+#endif
+	{ CFI_MFR_AMD, 0x0050, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x0053, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x0055, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x0056, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x005C, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x005F, fixup_use_secsi },
+	{ CFI_MFR_AMD, 0x0c01, fixup_s29gl064n_sectors },
+	{ CFI_MFR_AMD, 0x1301, fixup_s29gl064n_sectors },
+	{ CFI_MFR_AMD, 0x1a00, fixup_s29gl032n_sectors },
+	{ CFI_MFR_AMD, 0x1a01, fixup_s29gl032n_sectors },
+	{ CFI_MFR_AMD, 0x3f00, fixup_s29ns512p_sectors },
+	{ CFI_MFR_SST, 0x536a, fixup_sst38vf640x_sectorsize }, /* SST38VF6402 */
+	{ CFI_MFR_SST, 0x536b, fixup_sst38vf640x_sectorsize }, /* SST38VF6401 */
+	{ CFI_MFR_SST, 0x536c, fixup_sst38vf640x_sectorsize }, /* SST38VF6404 */
+	{ CFI_MFR_SST, 0x536d, fixup_sst38vf640x_sectorsize }, /* SST38VF6403 */
+#if !FORCE_WORD_WRITE
+	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_write_buffers },
+#endif
+	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_quirks },
+	{ 0, 0, NULL }
+};
+static struct cfi_fixup jedec_fixup_table[] = {
+	{ CFI_MFR_SST, SST49LF004B, fixup_use_fwh_lock },
+	{ CFI_MFR_SST, SST49LF040B, fixup_use_fwh_lock },
+	{ CFI_MFR_SST, SST49LF008A, fixup_use_fwh_lock },
+	{ 0, 0, NULL }
+};
+
+static struct cfi_fixup fixup_table[] = {
+	/* The CFI vendor ids and the JEDEC vendor IDs appear
+	 * to be common.  It is like the devices id's are as
+	 * well.  This table is to pick all cases where
+	 * we know that is the case.
+	 */
+	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_erase_chip },
+	{ CFI_MFR_ATMEL, AT49BV6416, fixup_use_atmel_lock },
+	{ 0, 0, NULL }
+};
+
+
+static void cfi_fixup_major_minor(struct cfi_private *cfi,
+				  struct cfi_pri_amdstd *extp)
+{
+	if (cfi->mfr == CFI_MFR_SAMSUNG) {
+		if ((extp->MajorVersion == '0' && extp->MinorVersion == '0') ||
+		    (extp->MajorVersion == '3' && extp->MinorVersion == '3')) {
+			/*
+			 * Samsung K8P2815UQB and K8D6x16UxM chips
+			 * report major=0 / minor=0.
+			 * K8D3x16UxC chips report major=3 / minor=3.
+			 */
+			printk(KERN_NOTICE "  Fixing Samsung's Amd/Fujitsu"
+			       " Extended Query version to 1.%c\n",
+			       extp->MinorVersion);
+			extp->MajorVersion = '1';
+		}
+	}
+
+	/*
+	 * SST 38VF640x chips report major=0xFF / minor=0xFF.
+	 */
+	if (cfi->mfr == CFI_MFR_SST && (cfi->id >> 4) == 0x0536) {
+		extp->MajorVersion = '1';
+		extp->MinorVersion = '0';
+	}
+}
+
+static int is_m29ew(struct cfi_private *cfi)
+{
+	if (cfi->mfr == CFI_MFR_INTEL &&
+	    ((cfi->device_type == CFI_DEVICETYPE_X8 && (cfi->id & 0xff) == 0x7e) ||
+	     (cfi->device_type == CFI_DEVICETYPE_X16 && cfi->id == 0x227e)))
+		return 1;
+	return 0;
+}
+
+/*
+ * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 20:
+ * Some revisions of the M29EW suffer from erase suspend hang ups. In
+ * particular, it can occur when the sequence
+ * Erase Confirm -> Suspend -> Program -> Resume
+ * causes a lockup due to internal timing issues. The consequence is that the
+ * erase cannot be resumed without inserting a dummy command after programming
+ * and prior to resuming. [...] The work-around is to issue a dummy write cycle
+ * that writes an F0 command code before the RESUME command.
+ */
+static void cfi_fixup_m29ew_erase_suspend(struct map_info *map,
+					  unsigned long adr)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	/* before resume, insert a dummy 0xF0 cycle for Micron M29EW devices */
+	if (is_m29ew(cfi))
+		map_write(map, CMD(0xF0), adr);
+}
+
+/*
+ * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 22:
+ *
+ * Some revisions of the M29EW (for example, A1 and A2 step revisions)
+ * are affected by a problem that could cause a hang up when an ERASE SUSPEND
+ * command is issued after an ERASE RESUME operation without waiting for a
+ * minimum delay.  The result is that once the ERASE seems to be completed
+ * (no bits are toggling), the contents of the Flash memory block on which
+ * the erase was ongoing could be inconsistent with the expected values
+ * (typically, the array value is stuck to the 0xC0, 0xC4, 0x80, or 0x84
+ * values), causing a consequent failure of the ERASE operation.
+ * The occurrence of this issue could be high, especially when file system
+ * operations on the Flash are intensive.  As a result, it is recommended
+ * that a patch be applied.  Intensive file system operations can cause many
+ * calls to the garbage routine to free Flash space (also by erasing physical
+ * Flash blocks) and as a result, many consecutive SUSPEND and RESUME
+ * commands can occur.  The problem disappears when a delay is inserted after
+ * the RESUME command by using the udelay() function available in Linux.
+ * The DELAY value must be tuned based on the customer's platform.
+ * The maximum value that fixes the problem in all cases is 500us.
+ * But, in our experience, a delay of 30 µs to 50 µs is sufficient
+ * in most cases.
+ * We have chosen 500µs because this latency is acceptable.
+ */
+static void cfi_fixup_m29ew_delay_after_resume(struct cfi_private *cfi)
+{
+	/*
+	 * Resolving the Delay After Resume Issue see Micron TN-13-07
+	 * Worst case delay must be 500µs but 30-50µs should be ok as well
+	 */
+	if (is_m29ew(cfi))
+		cfi_udelay(500);
+}
+
+struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	struct device_node __maybe_unused *np = map->device_node;
+	struct mtd_info *mtd;
+	int i;
+
+	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
+	if (!mtd)
+		return NULL;
+	mtd->priv = map;
+	mtd->type = MTD_NORFLASH;
+
+	/* Fill in the default mtd operations */
+	mtd->_erase   = cfi_amdstd_erase_varsize;
+	mtd->_write   = cfi_amdstd_write_words;
+	mtd->_read    = cfi_amdstd_read;
+	mtd->_sync    = cfi_amdstd_sync;
+	mtd->_suspend = cfi_amdstd_suspend;
+	mtd->_resume  = cfi_amdstd_resume;
+	mtd->_read_user_prot_reg = cfi_amdstd_read_user_prot_reg;
+	mtd->_read_fact_prot_reg = cfi_amdstd_read_fact_prot_reg;
+	mtd->_get_fact_prot_info = cfi_amdstd_get_fact_prot_info;
+	mtd->_get_user_prot_info = cfi_amdstd_get_user_prot_info;
+	mtd->_write_user_prot_reg = cfi_amdstd_write_user_prot_reg;
+	mtd->_lock_user_prot_reg = cfi_amdstd_lock_user_prot_reg;
+	mtd->flags   = MTD_CAP_NORFLASH;
+	mtd->name    = map->name;
+	mtd->writesize = 1;
+	mtd->writebufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
+
+	pr_debug("MTD %s(): write buffer size %d\n", __func__,
+			mtd->writebufsize);
+
+	mtd->_panic_write = cfi_amdstd_panic_write;
+	mtd->reboot_notifier.notifier_call = cfi_amdstd_reboot;
+
+	if (cfi->cfi_mode==CFI_MODE_CFI){
+		unsigned char bootloc;
+		__u16 adr = primary?cfi->cfiq->P_ADR:cfi->cfiq->A_ADR;
+		struct cfi_pri_amdstd *extp;
+
+		extp = (struct cfi_pri_amdstd*)cfi_read_pri(map, adr, sizeof(*extp), "Amd/Fujitsu");
+		if (extp) {
+			/*
+			 * It's a real CFI chip, not one for which the probe
+			 * routine faked a CFI structure.
+			 */
+			cfi_fixup_major_minor(cfi, extp);
+
+			/*
+			 * Valid primary extension versions are: 1.0, 1.1, 1.2, 1.3, 1.4, 1.5
+			 * see: http://cs.ozerki.net/zap/pub/axim-x5/docs/cfi_r20.pdf, page 19 
+			 *      http://www.spansion.com/Support/AppNotes/cfi_100_20011201.pdf
+			 *      http://www.spansion.com/Support/Datasheets/s29ws-p_00_a12_e.pdf
+			 *      http://www.spansion.com/Support/Datasheets/S29GL_128S_01GS_00_02_e.pdf
+			 */
+			if (extp->MajorVersion != '1' ||
+			    (extp->MajorVersion == '1' && (extp->MinorVersion < '0' || extp->MinorVersion > '5'))) {
+				printk(KERN_ERR "  Unknown Amd/Fujitsu Extended Query "
+				       "version %c.%c (%#02x/%#02x).\n",
+				       extp->MajorVersion, extp->MinorVersion,
+				       extp->MajorVersion, extp->MinorVersion);
+				kfree(extp);
+				kfree(mtd);
+				return NULL;
+			}
+
+			printk(KERN_INFO "  Amd/Fujitsu Extended Query version %c.%c.\n",
+			       extp->MajorVersion, extp->MinorVersion);
+
+			/* Install our own private info structure */
+			cfi->cmdset_priv = extp;
+
+			/* Apply cfi device specific fixups */
+			cfi_fixup(mtd, cfi_fixup_table);
+
+#ifdef DEBUG_CFI_FEATURES
+			/* Tell the user about it in lots of lovely detail */
+			cfi_tell_features(extp);
+#endif
+
+#ifdef CONFIG_OF
+			if (np && of_property_read_bool(
+				    np, "use-advanced-sector-protection")
+			    && extp->BlkProtUnprot == 8) {
+				printk(KERN_INFO "  Advanced Sector Protection (PPB Locking) supported\n");
+				mtd->_lock = cfi_ppb_lock;
+				mtd->_unlock = cfi_ppb_unlock;
+				mtd->_is_locked = cfi_ppb_is_locked;
+			}
+#endif
+
+			bootloc = extp->TopBottom;
+			if ((bootloc < 2) || (bootloc > 5)) {
+				printk(KERN_WARNING "%s: CFI contains unrecognised boot "
+				       "bank location (%d). Assuming bottom.\n",
+				       map->name, bootloc);
+				bootloc = 2;
+			}
+
+			if (bootloc == 3 && cfi->cfiq->NumEraseRegions > 1) {
+				printk(KERN_WARNING "%s: Swapping erase regions for top-boot CFI table.\n", map->name);
+
+				for (i=0; i<cfi->cfiq->NumEraseRegions / 2; i++) {
+					int j = (cfi->cfiq->NumEraseRegions-1)-i;
+
+					swap(cfi->cfiq->EraseRegionInfo[i],
+					     cfi->cfiq->EraseRegionInfo[j]);
+				}
+			}
+			/* Set the default CFI lock/unlock addresses */
+			cfi->addr_unlock1 = 0x555;
+			cfi->addr_unlock2 = 0x2aa;
+		}
+		cfi_fixup(mtd, cfi_nopri_fixup_table);
+
+		if (!cfi->addr_unlock1 || !cfi->addr_unlock2) {
+			kfree(mtd);
+			return NULL;
+		}
+
+	} /* CFI mode */
+	else if (cfi->cfi_mode == CFI_MODE_JEDEC) {
+		/* Apply jedec specific fixups */
+		cfi_fixup(mtd, jedec_fixup_table);
+	}
+	/* Apply generic fixups */
+	cfi_fixup(mtd, fixup_table);
+
+	for (i=0; i< cfi->numchips; i++) {
+		cfi->chips[i].word_write_time = 1<<cfi->cfiq->WordWriteTimeoutTyp;
+		cfi->chips[i].buffer_write_time = 1<<cfi->cfiq->BufWriteTimeoutTyp;
+		cfi->chips[i].erase_time = 1<<cfi->cfiq->BlockEraseTimeoutTyp;
+		/*
+		 * First calculate the timeout max according to timeout field
+		 * of struct cfi_ident that probed from chip's CFI aera, if
+		 * available. Specify a minimum of 2000us, in case the CFI data
+		 * is wrong.
+		 */
+		if (cfi->cfiq->BufWriteTimeoutTyp &&
+		    cfi->cfiq->BufWriteTimeoutMax)
+			cfi->chips[i].buffer_write_time_max =
+				1 << (cfi->cfiq->BufWriteTimeoutTyp +
+				      cfi->cfiq->BufWriteTimeoutMax);
+		else
+			cfi->chips[i].buffer_write_time_max = 0;
+
+		cfi->chips[i].buffer_write_time_max =
+			max(cfi->chips[i].buffer_write_time_max, 2000);
+
+		cfi->chips[i].ref_point_counter = 0;
+		init_waitqueue_head(&(cfi->chips[i].wq));
+	}
+
+	map->fldrv = &cfi_amdstd_chipdrv;
+
+	return cfi_amdstd_setup(mtd);
+}
+struct mtd_info *cfi_cmdset_0006(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
+struct mtd_info *cfi_cmdset_0701(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
+EXPORT_SYMBOL_GPL(cfi_cmdset_0002);
+EXPORT_SYMBOL_GPL(cfi_cmdset_0006);
+EXPORT_SYMBOL_GPL(cfi_cmdset_0701);
+
+static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long devsize = (1<<cfi->cfiq->DevSize) * cfi->interleave;
+	unsigned long offset = 0;
+	int i,j;
+
+	printk(KERN_NOTICE "number of %s chips: %d\n",
+	       (cfi->cfi_mode == CFI_MODE_CFI)?"CFI":"JEDEC",cfi->numchips);
+	/* Select the correct geometry setup */
+	mtd->size = devsize * cfi->numchips;
+
+	mtd->numeraseregions = cfi->cfiq->NumEraseRegions * cfi->numchips;
+	mtd->eraseregions = kmalloc_array(mtd->numeraseregions,
+					  sizeof(struct mtd_erase_region_info),
+					  GFP_KERNEL);
+	if (!mtd->eraseregions)
+		goto setup_err;
+
+	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
+		unsigned long ernum, ersize;
+		ersize = ((cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff) * cfi->interleave;
+		ernum = (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1;
+
+		if (mtd->erasesize < ersize) {
+			mtd->erasesize = ersize;
+		}
+		for (j=0; j<cfi->numchips; j++) {
+			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].offset = (j*devsize)+offset;
+			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].erasesize = ersize;
+			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].numblocks = ernum;
+		}
+		offset += (ersize * ernum);
+	}
+	if (offset != devsize) {
+		/* Argh */
+		printk(KERN_WARNING "Sum of regions (%lx) != total size of set of interleaved chips (%lx)\n", offset, devsize);
+		goto setup_err;
+	}
+
+	__module_get(THIS_MODULE);
+	register_reboot_notifier(&mtd->reboot_notifier);
+	return mtd;
+
+ setup_err:
+	kfree(mtd->eraseregions);
+	kfree(mtd);
+	kfree(cfi->cmdset_priv);
+	return NULL;
+}
+
+/*
+ * Return true if the chip is ready and has the correct value.
+ *
+ * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
+ * non-suspended sector) and is indicated by no toggle bits toggling.
+ *
+ * Error are indicated by toggling bits or bits held with the wrong value,
+ * or with bits toggling.
+ *
+ * Note that anything more complicated than checking if no bits are toggling
+ * (including checking DQ5 for an error status) is tricky to get working
+ * correctly and is therefore not done	(particularly with interleaved chips
+ * as each chip must be checked independently of the others).
+ */
+static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
+			       unsigned long addr, map_word *expected)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	map_word d, t;
+	int ret;
+
+	if (cfi_use_status_reg(cfi)) {
+		map_word ready = CMD(CFI_SR_DRB);
+		/*
+		 * For chips that support status register, check device
+		 * ready bit
+		 */
+		cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
+				 cfi->device_type, NULL);
+		t = map_read(map, addr);
+
+		return map_word_andequal(map, t, ready, ready);
+	}
+
+	d = map_read(map, addr);
+	t = map_read(map, addr);
+
+	ret = map_word_equal(map, d, t);
+
+	if (!ret || !expected)
+		return ret;
+
+	return map_word_equal(map, t, *expected);
+}
+
+static int __xipram chip_good(struct map_info *map, struct flchip *chip,
+			      unsigned long addr, map_word *expected)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	map_word *datum = expected;
+
+	if (cfi->quirks & CFI_QUIRK_DQ_TRUE_DATA)
+		datum = NULL;
+
+	return chip_ready(map, chip, addr, datum);
+}
+
+static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long timeo;
+	struct cfi_pri_amdstd *cfip = (struct cfi_pri_amdstd *)cfi->cmdset_priv;
+
+ resettime:
+	timeo = jiffies + HZ;
+ retry:
+	switch (chip->state) {
+
+	case FL_STATUS:
+		for (;;) {
+			if (chip_ready(map, chip, adr, NULL))
+				break;
+
+			if (time_after(jiffies, timeo)) {
+				printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
+				return -EIO;
+			}
+			mutex_unlock(&chip->mutex);
+			cfi_udelay(1);
+			mutex_lock(&chip->mutex);
+			/* Someone else might have been playing with it. */
+			goto retry;
+		}
+
+	case FL_READY:
+	case FL_CFI_QUERY:
+	case FL_JEDEC_QUERY:
+		return 0;
+
+	case FL_ERASING:
+		if (!cfip || !(cfip->EraseSuspend & (0x1|0x2)) ||
+		    !(mode == FL_READY || mode == FL_POINT ||
+		    (mode == FL_WRITING && (cfip->EraseSuspend & 0x2))))
+			goto sleep;
+
+		/* Do not allow suspend iff read/write to EB address */
+		if ((adr & chip->in_progress_block_mask) ==
+		    chip->in_progress_block_addr)
+			goto sleep;
+
+		/* Erase suspend */
+		/* It's harmless to issue the Erase-Suspend and Erase-Resume
+		 * commands when the erase algorithm isn't in progress. */
+		map_write(map, CMD(0xB0), chip->in_progress_block_addr);
+		chip->oldstate = FL_ERASING;
+		chip->state = FL_ERASE_SUSPENDING;
+		chip->erase_suspended = 1;
+		for (;;) {
+			if (chip_ready(map, chip, adr, NULL))
+				break;
+
+			if (time_after(jiffies, timeo)) {
+				/* Should have suspended the erase by now.
+				 * Send an Erase-Resume command as either
+				 * there was an error (so leave the erase
+				 * routine to recover from it) or we trying to
+				 * use the erase-in-progress sector. */
+				put_chip(map, chip, adr);
+				printk(KERN_ERR "MTD %s(): chip not ready after erase suspend\n", __func__);
+				return -EIO;
+			}
+
+			mutex_unlock(&chip->mutex);
+			cfi_udelay(1);
+			mutex_lock(&chip->mutex);
+			/* Nobody will touch it while it's in state FL_ERASE_SUSPENDING.
+			   So we can just loop here. */
+		}
+		chip->state = FL_READY;
+		return 0;
+
+	case FL_XIP_WHILE_ERASING:
+		if (mode != FL_READY && mode != FL_POINT &&
+		    (!cfip || !(cfip->EraseSuspend&2)))
+			goto sleep;
+		chip->oldstate = chip->state;
+		chip->state = FL_READY;
+		return 0;
+
+	case FL_SHUTDOWN:
+		/* The machine is rebooting */
+		return -EIO;
+
+	case FL_POINT:
+		/* Only if there's no operation suspended... */
+		if (mode == FL_READY && chip->oldstate == FL_READY)
+			return 0;
+		fallthrough;
+	default:
+	sleep:
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		add_wait_queue(&chip->wq, &wait);
+		mutex_unlock(&chip->mutex);
+		schedule();
+		remove_wait_queue(&chip->wq, &wait);
+		mutex_lock(&chip->mutex);
+		goto resettime;
+	}
+}
+
+
+static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	switch(chip->oldstate) {
+	case FL_ERASING:
+		cfi_fixup_m29ew_erase_suspend(map,
+			chip->in_progress_block_addr);
+		map_write(map, cfi->sector_erase_cmd, chip->in_progress_block_addr);
+		cfi_fixup_m29ew_delay_after_resume(cfi);
+		chip->oldstate = FL_READY;
+		chip->state = FL_ERASING;
+		break;
+
+	case FL_XIP_WHILE_ERASING:
+		chip->state = chip->oldstate;
+		chip->oldstate = FL_READY;
+		break;
+
+	case FL_READY:
+	case FL_STATUS:
+		break;
+	default:
+		printk(KERN_ERR "MTD: put_chip() called with oldstate %d!!\n", chip->oldstate);
+	}
+	wake_up(&chip->wq);
+}
+
+#ifdef CONFIG_MTD_XIP
+
+/*
+ * No interrupt what so ever can be serviced while the flash isn't in array
+ * mode.  This is ensured by the xip_disable() and xip_enable() functions
+ * enclosing any code path where the flash is known not to be in array mode.
+ * And within a XIP disabled code path, only functions marked with __xipram
+ * may be called and nothing else (it's a good thing to inspect generated
+ * assembly to make sure inline functions were actually inlined and that gcc
+ * didn't emit calls to its own support functions). Also configuring MTD CFI
+ * support to a single buswidth and a single interleave is also recommended.
+ */
+
+static void xip_disable(struct map_info *map, struct flchip *chip,
+			unsigned long adr)
+{
+	/* TODO: chips with no XIP use should ignore and return */
+	(void) map_read(map, adr); /* ensure mmu mapping is up to date */
+	local_irq_disable();
+}
+
+static void __xipram xip_enable(struct map_info *map, struct flchip *chip,
+				unsigned long adr)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	if (chip->state != FL_POINT && chip->state != FL_READY) {
+		map_write(map, CMD(0xf0), adr);
+		chip->state = FL_READY;
+	}
+	(void) map_read(map, adr);
+	xip_iprefetch();
+	local_irq_enable();
+}
+
+/*
+ * When a delay is required for the flash operation to complete, the
+ * xip_udelay() function is polling for both the given timeout and pending
+ * (but still masked) hardware interrupts.  Whenever there is an interrupt
+ * pending then the flash erase operation is suspended, array mode restored
+ * and interrupts unmasked.  Task scheduling might also happen at that
+ * point.  The CPU eventually returns from the interrupt or the call to
+ * schedule() and the suspended flash operation is resumed for the remaining
+ * of the delay period.
+ *
+ * Warning: this function _will_ fool interrupt latency tracing tools.
+ */
+
+static void __xipram xip_udelay(struct map_info *map, struct flchip *chip,
+				unsigned long adr, int usec)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
+	map_word status, OK = CMD(0x80);
+	unsigned long suspended, start = xip_currtime();
+	flstate_t oldstate;
+
+	do {
+		cpu_relax();
+		if (xip_irqpending() && extp &&
+		    ((chip->state == FL_ERASING && (extp->EraseSuspend & 2))) &&
+		    (cfi_interleave_is_1(cfi) || chip->oldstate == FL_READY)) {
+			/*
+			 * Let's suspend the erase operation when supported.
+			 * Note that we currently don't try to suspend
+			 * interleaved chips if there is already another
+			 * operation suspended (imagine what happens
+			 * when one chip was already done with the current
+			 * operation while another chip suspended it, then
+			 * we resume the whole thing at once).  Yes, it
+			 * can happen!
+			 */
+			map_write(map, CMD(0xb0), adr);
+			usec -= xip_elapsed_since(start);
+			suspended = xip_currtime();
+			do {
+				if (xip_elapsed_since(suspended) > 100000) {
+					/*
+					 * The chip doesn't want to suspend
+					 * after waiting for 100 msecs.
+					 * This is a critical error but there
+					 * is not much we can do here.
+					 */
+					return;
+				}
+				status = map_read(map, adr);
+			} while (!map_word_andequal(map, status, OK, OK));
+
+			/* Suspend succeeded */
+			oldstate = chip->state;
+			if (!map_word_bitsset(map, status, CMD(0x40)))
+				break;
+			chip->state = FL_XIP_WHILE_ERASING;
+			chip->erase_suspended = 1;
+			map_write(map, CMD(0xf0), adr);
+			(void) map_read(map, adr);
+			xip_iprefetch();
+			local_irq_enable();
+			mutex_unlock(&chip->mutex);
+			xip_iprefetch();
+			cond_resched();
+
+			/*
+			 * We're back.  However someone else might have
+			 * decided to go write to the chip if we are in
+			 * a suspended erase state.  If so let's wait
+			 * until it's done.
+			 */
+			mutex_lock(&chip->mutex);
+			while (chip->state != FL_XIP_WHILE_ERASING) {
+				DECLARE_WAITQUEUE(wait, current);
+				set_current_state(TASK_UNINTERRUPTIBLE);
+				add_wait_queue(&chip->wq, &wait);
+				mutex_unlock(&chip->mutex);
+				schedule();
+				remove_wait_queue(&chip->wq, &wait);
+				mutex_lock(&chip->mutex);
+			}
+			/* Disallow XIP again */
+			local_irq_disable();
+
+			/* Correct Erase Suspend Hangups for M29EW */
+			cfi_fixup_m29ew_erase_suspend(map, adr);
+			/* Resume the write or erase operation */
+			map_write(map, cfi->sector_erase_cmd, adr);
+			chip->state = oldstate;
+			start = xip_currtime();
+		} else if (usec >= 1000000/HZ) {
+			/*
+			 * Try to save on CPU power when waiting delay
+			 * is at least a system timer tick period.
+			 * No need to be extremely accurate here.
+			 */
+			xip_cpu_idle();
+		}
+		status = map_read(map, adr);
+	} while (!map_word_andequal(map, status, OK, OK)
+		 && xip_elapsed_since(start) < usec);
+}
+
+#define UDELAY(map, chip, adr, usec)  xip_udelay(map, chip, adr, usec)
+
+/*
+ * The INVALIDATE_CACHED_RANGE() macro is normally used in parallel while
+ * the flash is actively programming or erasing since we have to poll for
+ * the operation to complete anyway.  We can't do that in a generic way with
+ * a XIP setup so do it before the actual flash operation in this case
+ * and stub it out from INVALIDATE_CACHE_UDELAY.
+ */
+#define XIP_INVAL_CACHED_RANGE(map, from, size)  \
+	INVALIDATE_CACHED_RANGE(map, from, size)
+
+#define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
+	UDELAY(map, chip, adr, usec)
+
+/*
+ * Extra notes:
+ *
+ * Activating this XIP support changes the way the code works a bit.  For
+ * example the code to suspend the current process when concurrent access
+ * happens is never executed because xip_udelay() will always return with the
+ * same chip state as it was entered with.  This is why there is no care for
+ * the presence of add_wait_queue() or schedule() calls from within a couple
+ * xip_disable()'d  areas of code, like in do_erase_oneblock for example.
+ * The queueing and scheduling are always happening within xip_udelay().
+ *
+ * Similarly, get_chip() and put_chip() just happen to always be executed
+ * with chip->state set to FL_READY (or FL_XIP_WHILE_*) where flash state
+ * is in array mode, therefore never executing many cases therein and not
+ * causing any problem with XIP.
+ */
+
+#else
+
+#define xip_disable(map, chip, adr)
+#define xip_enable(map, chip, adr)
+#define XIP_INVAL_CACHED_RANGE(x...)
+
+#define UDELAY(map, chip, adr, usec)  \
+do {  \
+	mutex_unlock(&chip->mutex);  \
+	cfi_udelay(usec);  \
+	mutex_lock(&chip->mutex);  \
+} while (0)
+
+#define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
+do {  \
+	mutex_unlock(&chip->mutex);  \
+	INVALIDATE_CACHED_RANGE(map, adr, len);  \
+	cfi_udelay(usec);  \
+	mutex_lock(&chip->mutex);  \
+} while (0)
+
+#endif
+
+static inline int do_read_onechip(struct map_info *map, struct flchip *chip, loff_t adr, size_t len, u_char *buf)
+{
+	unsigned long cmd_addr;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret;
+
+	adr += chip->start;
+
+	/* Ensure cmd read/writes are aligned. */
+	cmd_addr = adr & ~(map_bankwidth(map)-1);
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, cmd_addr, FL_READY);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	if (chip->state != FL_POINT && chip->state != FL_READY) {
+		map_write(map, CMD(0xf0), cmd_addr);
+		chip->state = FL_READY;
+	}
+
+	map_copy_from(map, buf, adr, len);
+
+	put_chip(map, chip, cmd_addr);
+
+	mutex_unlock(&chip->mutex);
+	return 0;
+}
+
+
+static int cfi_amdstd_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long ofs;
+	int chipnum;
+	int ret = 0;
+
+	/* ofs: offset within the first chip that the first read should start */
+	chipnum = (from >> cfi->chipshift);
+	ofs = from - (chipnum <<  cfi->chipshift);
+
+	while (len) {
+		unsigned long thislen;
+
+		if (chipnum >= cfi->numchips)
+			break;
+
+		if ((len + ofs -1) >> cfi->chipshift)
+			thislen = (1<<cfi->chipshift) - ofs;
+		else
+			thislen = len;
+
+		ret = do_read_onechip(map, &cfi->chips[chipnum], ofs, thislen, buf);
+		if (ret)
+			break;
+
+		*retlen += thislen;
+		len -= thislen;
+		buf += thislen;
+
+		ofs = 0;
+		chipnum++;
+	}
+	return ret;
+}
+
+typedef int (*otp_op_t)(struct map_info *map, struct flchip *chip,
+			loff_t adr, size_t len, u_char *buf, size_t grouplen);
+
+static inline void otp_enter(struct map_info *map, struct flchip *chip,
+			     loff_t adr, size_t len)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x88, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+
+	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
+}
+
+static inline void otp_exit(struct map_info *map, struct flchip *chip,
+			    loff_t adr, size_t len)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x90, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x00, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+
+	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
+}
+
+static inline int do_read_secsi_onechip(struct map_info *map,
+					struct flchip *chip, loff_t adr,
+					size_t len, u_char *buf,
+					size_t grouplen)
+{
+	DECLARE_WAITQUEUE(wait, current);
+
+ retry:
+	mutex_lock(&chip->mutex);
+
+	if (chip->state != FL_READY){
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		add_wait_queue(&chip->wq, &wait);
+
+		mutex_unlock(&chip->mutex);
+
+		schedule();
+		remove_wait_queue(&chip->wq, &wait);
+
+		goto retry;
+	}
+
+	adr += chip->start;
+
+	chip->state = FL_READY;
+
+	otp_enter(map, chip, adr, len);
+	map_copy_from(map, buf, adr, len);
+	otp_exit(map, chip, adr, len);
+
+	wake_up(&chip->wq);
+	mutex_unlock(&chip->mutex);
+
+	return 0;
+}
+
+static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long ofs;
+	int chipnum;
+	int ret = 0;
+
+	/* ofs: offset within the first chip that the first read should start */
+	/* 8 secsi bytes per chip */
+	chipnum=from>>3;
+	ofs=from & 7;
+
+	while (len) {
+		unsigned long thislen;
+
+		if (chipnum >= cfi->numchips)
+			break;
+
+		if ((len + ofs -1) >> 3)
+			thislen = (1<<3) - ofs;
+		else
+			thislen = len;
+
+		ret = do_read_secsi_onechip(map, &cfi->chips[chipnum], ofs,
+					    thislen, buf, 0);
+		if (ret)
+			break;
+
+		*retlen += thislen;
+		len -= thislen;
+		buf += thislen;
+
+		ofs = 0;
+		chipnum++;
+	}
+	return ret;
+}
+
+static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
+				     unsigned long adr, map_word datum,
+				     int mode);
+
+static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
+			size_t len, u_char *buf, size_t grouplen)
+{
+	int ret;
+	while (len) {
+		unsigned long bus_ofs = adr & ~(map_bankwidth(map)-1);
+		int gap = adr - bus_ofs;
+		int n = min_t(int, len, map_bankwidth(map) - gap);
+		map_word datum = map_word_ff(map);
+
+		if (n != map_bankwidth(map)) {
+			/* partial write of a word, load old contents */
+			otp_enter(map, chip, bus_ofs, map_bankwidth(map));
+			datum = map_read(map, bus_ofs);
+			otp_exit(map, chip, bus_ofs, map_bankwidth(map));
+		}
+
+		datum = map_word_load_partial(map, datum, buf, gap, n);
+		ret = do_write_oneword(map, chip, bus_ofs, datum, FL_OTP_WRITE);
+		if (ret)
+			return ret;
+
+		adr += n;
+		buf += n;
+		len -= n;
+	}
+
+	return 0;
+}
+
+static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
+		       size_t len, u_char *buf, size_t grouplen)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	uint8_t lockreg;
+	unsigned long timeo;
+	int ret;
+
+	/* make sure area matches group boundaries */
+	if ((adr != 0) || (len != grouplen))
+		return -EINVAL;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, chip->start, FL_LOCKING);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+	chip->state = FL_LOCKING;
+
+	/* Enter lock register command */
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x40, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+
+	/* read lock register */
+	lockreg = cfi_read_query(map, 0);
+
+	/* set bit 0 to protect extended memory block */
+	lockreg &= ~0x01;
+
+	/* set bit 0 to protect extended memory block */
+	/* write lock register */
+	map_write(map, CMD(0xA0), chip->start);
+	map_write(map, CMD(lockreg), chip->start);
+
+	/* wait for chip to become ready */
+	timeo = jiffies + msecs_to_jiffies(2);
+	for (;;) {
+		if (chip_ready(map, chip, adr, NULL))
+			break;
+
+		if (time_after(jiffies, timeo)) {
+			pr_err("Waiting for chip to be ready timed out.\n");
+			ret = -EIO;
+			break;
+		}
+		UDELAY(map, chip, 0, 1);
+	}
+
+	/* exit protection commands */
+	map_write(map, CMD(0x90), chip->start);
+	map_write(map, CMD(0x00), chip->start);
+
+	chip->state = FL_READY;
+	put_chip(map, chip, chip->start);
+	mutex_unlock(&chip->mutex);
+
+	return ret;
+}
+
+static int cfi_amdstd_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
+			       size_t *retlen, u_char *buf,
+			       otp_op_t action, int user_regs)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ofs_factor = cfi->interleave * cfi->device_type;
+	unsigned long base;
+	int chipnum;
+	struct flchip *chip;
+	uint8_t otp, lockreg;
+	int ret;
+
+	size_t user_size, factory_size, otpsize;
+	loff_t user_offset, factory_offset, otpoffset;
+	int user_locked = 0, otplocked;
+
+	*retlen = 0;
+
+	for (chipnum = 0; chipnum < cfi->numchips; chipnum++) {
+		chip = &cfi->chips[chipnum];
+		factory_size = 0;
+		user_size = 0;
+
+		/* Micron M29EW family */
+		if (is_m29ew(cfi)) {
+			base = chip->start;
+
+			/* check whether secsi area is factory locked
+			   or user lockable */
+			mutex_lock(&chip->mutex);
+			ret = get_chip(map, chip, base, FL_CFI_QUERY);
+			if (ret) {
+				mutex_unlock(&chip->mutex);
+				return ret;
+			}
+			cfi_qry_mode_on(base, map, cfi);
+			otp = cfi_read_query(map, base + 0x3 * ofs_factor);
+			cfi_qry_mode_off(base, map, cfi);
+			put_chip(map, chip, base);
+			mutex_unlock(&chip->mutex);
+
+			if (otp & 0x80) {
+				/* factory locked */
+				factory_offset = 0;
+				factory_size = 0x100;
+			} else {
+				/* customer lockable */
+				user_offset = 0;
+				user_size = 0x100;
+
+				mutex_lock(&chip->mutex);
+				ret = get_chip(map, chip, base, FL_LOCKING);
+				if (ret) {
+					mutex_unlock(&chip->mutex);
+					return ret;
+				}
+
+				/* Enter lock register command */
+				cfi_send_gen_cmd(0xAA, cfi->addr_unlock1,
+						 chip->start, map, cfi,
+						 cfi->device_type, NULL);
+				cfi_send_gen_cmd(0x55, cfi->addr_unlock2,
+						 chip->start, map, cfi,
+						 cfi->device_type, NULL);
+				cfi_send_gen_cmd(0x40, cfi->addr_unlock1,
+						 chip->start, map, cfi,
+						 cfi->device_type, NULL);
+				/* read lock register */
+				lockreg = cfi_read_query(map, 0);
+				/* exit protection commands */
+				map_write(map, CMD(0x90), chip->start);
+				map_write(map, CMD(0x00), chip->start);
+				put_chip(map, chip, chip->start);
+				mutex_unlock(&chip->mutex);
+
+				user_locked = ((lockreg & 0x01) == 0x00);
+			}
+		}
+
+		otpsize = user_regs ? user_size : factory_size;
+		if (!otpsize)
+			continue;
+		otpoffset = user_regs ? user_offset : factory_offset;
+		otplocked = user_regs ? user_locked : 1;
+
+		if (!action) {
+			/* return otpinfo */
+			struct otp_info *otpinfo;
+			len -= sizeof(*otpinfo);
+			if (len <= 0)
+				return -ENOSPC;
+			otpinfo = (struct otp_info *)buf;
+			otpinfo->start = from;
+			otpinfo->length = otpsize;
+			otpinfo->locked = otplocked;
+			buf += sizeof(*otpinfo);
+			*retlen += sizeof(*otpinfo);
+			from += otpsize;
+		} else if ((from < otpsize) && (len > 0)) {
+			size_t size;
+			size = (len < otpsize - from) ? len : otpsize - from;
+			ret = action(map, chip, otpoffset + from, size, buf,
+				     otpsize);
+			if (ret < 0)
+				return ret;
+
+			buf += size;
+			len -= size;
+			*retlen += size;
+			from = 0;
+		} else {
+			from -= otpsize;
+		}
+	}
+	return 0;
+}
+
+static int cfi_amdstd_get_fact_prot_info(struct mtd_info *mtd, size_t len,
+					 size_t *retlen, struct otp_info *buf)
+{
+	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
+				   NULL, 0);
+}
+
+static int cfi_amdstd_get_user_prot_info(struct mtd_info *mtd, size_t len,
+					 size_t *retlen, struct otp_info *buf)
+{
+	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
+				   NULL, 1);
+}
+
+static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
+					 size_t len, size_t *retlen,
+					 u_char *buf)
+{
+	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
+				   buf, do_read_secsi_onechip, 0);
+}
+
+static int cfi_amdstd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
+					 size_t len, size_t *retlen,
+					 u_char *buf)
+{
+	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
+				   buf, do_read_secsi_onechip, 1);
+}
+
+static int cfi_amdstd_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
+					  size_t len, size_t *retlen,
+					  u_char *buf)
+{
+	return cfi_amdstd_otp_walk(mtd, from, len, retlen, buf,
+				   do_otp_write, 1);
+}
+
+static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
+					 size_t len)
+{
+	size_t retlen;
+	return cfi_amdstd_otp_walk(mtd, from, len, &retlen, NULL,
+				   do_otp_lock, 1);
+}
+
+static int __xipram do_write_oneword_once(struct map_info *map,
+					  struct flchip *chip,
+					  unsigned long adr, map_word datum,
+					  int mode, struct cfi_private *cfi)
+{
+	unsigned long timeo = jiffies + HZ;
+	/*
+	 * We use a 1ms + 1 jiffies generic timeout for writes (most devices
+	 * have a max write time of a few hundreds usec). However, we should
+	 * use the maximum timeout value given by the chip at probe time
+	 * instead.  Unfortunately, struct flchip does have a field for
+	 * maximum timeout, only for typical which can be far too short
+	 * depending of the conditions.	 The ' + 1' is to avoid having a
+	 * timeout of 0 jiffies if HZ is smaller than 1000.
+	 */
+	unsigned long uWriteTimeout = (HZ / 1000) + 1;
+	int ret = 0;
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	map_write(map, datum, adr);
+	chip->state = mode;
+
+	INVALIDATE_CACHE_UDELAY(map, chip,
+				adr, map_bankwidth(map),
+				chip->word_write_time);
+
+	/* See comment above for timeout value. */
+	timeo = jiffies + uWriteTimeout;
+	for (;;) {
+		if (chip->state != mode) {
+			/* Someone's suspended the write. Sleep */
+			DECLARE_WAITQUEUE(wait, current);
+
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&chip->wq, &wait);
+			mutex_unlock(&chip->mutex);
+			schedule();
+			remove_wait_queue(&chip->wq, &wait);
+			timeo = jiffies + (HZ / 2); /* FIXME */
+			mutex_lock(&chip->mutex);
+			continue;
+		}
+
+		/*
+		 * We check "time_after" and "!chip_good" before checking
+		 * "chip_good" to avoid the failure due to scheduling.
+		 */
+		if (time_after(jiffies, timeo) &&
+		    !chip_good(map, chip, adr, &datum)) {
+			xip_enable(map, chip, adr);
+			printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
+			xip_disable(map, chip, adr);
+			ret = -EIO;
+			break;
+		}
+
+		if (chip_good(map, chip, adr, &datum)) {
+			if (cfi_check_err_status(map, chip, adr))
+				ret = -EIO;
+			break;
+		}
+
+		/* Latency issues. Drop the lock, wait a while and retry */
+		UDELAY(map, chip, adr, 1);
+	}
+
+	return ret;
+}
+
+static int __xipram do_write_oneword_start(struct map_info *map,
+					   struct flchip *chip,
+					   unsigned long adr, int mode)
+{
+	int ret;
+
+	mutex_lock(&chip->mutex);
+
+	ret = get_chip(map, chip, adr, mode);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	if (mode == FL_OTP_WRITE)
+		otp_enter(map, chip, adr, map_bankwidth(map));
+
+	return ret;
+}
+
+static void __xipram do_write_oneword_done(struct map_info *map,
+					   struct flchip *chip,
+					   unsigned long adr, int mode)
+{
+	if (mode == FL_OTP_WRITE)
+		otp_exit(map, chip, adr, map_bankwidth(map));
+
+	chip->state = FL_READY;
+	DISABLE_VPP(map);
+	put_chip(map, chip, adr);
+
+	mutex_unlock(&chip->mutex);
+}
+
+static int __xipram do_write_oneword_retry(struct map_info *map,
+					   struct flchip *chip,
+					   unsigned long adr, map_word datum,
+					   int mode)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret = 0;
+	map_word oldd;
+	int retry_cnt = 0;
+
+	/*
+	 * Check for a NOP for the case when the datum to write is already
+	 * present - it saves time and works around buggy chips that corrupt
+	 * data at other locations when 0xff is written to a location that
+	 * already contains 0xff.
+	 */
+	oldd = map_read(map, adr);
+	if (map_word_equal(map, oldd, datum)) {
+		pr_debug("MTD %s(): NOP\n", __func__);
+		return ret;
+	}
+
+	XIP_INVAL_CACHED_RANGE(map, adr, map_bankwidth(map));
+	ENABLE_VPP(map);
+	xip_disable(map, chip, adr);
+
+ retry:
+	ret = do_write_oneword_once(map, chip, adr, datum, mode, cfi);
+	if (ret) {
+		/* reset on all failures. */
+		map_write(map, CMD(0xF0), chip->start);
+		/* FIXME - should have reset delay before continuing */
+
+		if (++retry_cnt <= MAX_RETRIES) {
+			ret = 0;
+			goto retry;
+		}
+	}
+	xip_enable(map, chip, adr);
+
+	return ret;
+}
+
+static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
+				     unsigned long adr, map_word datum,
+				     int mode)
+{
+	int ret;
+
+	adr += chip->start;
+
+	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n", __func__, adr,
+		 datum.x[0]);
+
+	ret = do_write_oneword_start(map, chip, adr, mode);
+	if (ret)
+		return ret;
+
+	ret = do_write_oneword_retry(map, chip, adr, datum, mode);
+
+	do_write_oneword_done(map, chip, adr, mode);
+
+	return ret;
+}
+
+
+static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
+				  size_t *retlen, const u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret;
+	int chipnum;
+	unsigned long ofs, chipstart;
+	DECLARE_WAITQUEUE(wait, current);
+
+	chipnum = to >> cfi->chipshift;
+	ofs = to  - (chipnum << cfi->chipshift);
+	chipstart = cfi->chips[chipnum].start;
+
+	/* If it's not bus-aligned, do the first byte write */
+	if (ofs & (map_bankwidth(map)-1)) {
+		unsigned long bus_ofs = ofs & ~(map_bankwidth(map)-1);
+		int i = ofs - bus_ofs;
+		int n = 0;
+		map_word tmp_buf;
+
+ retry:
+		mutex_lock(&cfi->chips[chipnum].mutex);
+
+		if (cfi->chips[chipnum].state != FL_READY) {
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
+
+			mutex_unlock(&cfi->chips[chipnum].mutex);
+
+			schedule();
+			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
+			goto retry;
+		}
+
+		/* Load 'tmp_buf' with old contents of flash */
+		tmp_buf = map_read(map, bus_ofs+chipstart);
+
+		mutex_unlock(&cfi->chips[chipnum].mutex);
+
+		/* Number of bytes to copy from buffer */
+		n = min_t(int, len, map_bankwidth(map)-i);
+
+		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
+
+		ret = do_write_oneword(map, &cfi->chips[chipnum],
+				       bus_ofs, tmp_buf, FL_WRITING);
+		if (ret)
+			return ret;
+
+		ofs += n;
+		buf += n;
+		(*retlen) += n;
+		len -= n;
+
+		if (ofs >> cfi->chipshift) {
+			chipnum ++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+		}
+	}
+
+	/* We are now aligned, write as much as possible */
+	while(len >= map_bankwidth(map)) {
+		map_word datum;
+
+		datum = map_word_load(map, buf);
+
+		ret = do_write_oneword(map, &cfi->chips[chipnum],
+				       ofs, datum, FL_WRITING);
+		if (ret)
+			return ret;
+
+		ofs += map_bankwidth(map);
+		buf += map_bankwidth(map);
+		(*retlen) += map_bankwidth(map);
+		len -= map_bankwidth(map);
+
+		if (ofs >> cfi->chipshift) {
+			chipnum ++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+			chipstart = cfi->chips[chipnum].start;
+		}
+	}
+
+	/* Write the trailing bytes if any */
+	if (len & (map_bankwidth(map)-1)) {
+		map_word tmp_buf;
+
+ retry1:
+		mutex_lock(&cfi->chips[chipnum].mutex);
+
+		if (cfi->chips[chipnum].state != FL_READY) {
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
+
+			mutex_unlock(&cfi->chips[chipnum].mutex);
+
+			schedule();
+			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
+			goto retry1;
+		}
+
+		tmp_buf = map_read(map, ofs + chipstart);
+
+		mutex_unlock(&cfi->chips[chipnum].mutex);
+
+		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
+
+		ret = do_write_oneword(map, &cfi->chips[chipnum],
+				       ofs, tmp_buf, FL_WRITING);
+		if (ret)
+			return ret;
+
+		(*retlen) += len;
+	}
+
+	return 0;
+}
+
+#if !FORCE_WORD_WRITE
+static int __xipram do_write_buffer_wait(struct map_info *map,
+					 struct flchip *chip, unsigned long adr,
+					 map_word datum)
+{
+	unsigned long timeo;
+	unsigned long u_write_timeout;
+	int ret = 0;
+
+	/*
+	 * Timeout is calculated according to CFI data, if available.
+	 * See more comments in cfi_cmdset_0002().
+	 */
+	u_write_timeout = usecs_to_jiffies(chip->buffer_write_time_max);
+	timeo = jiffies + u_write_timeout;
+
+	for (;;) {
+		if (chip->state != FL_WRITING) {
+			/* Someone's suspended the write. Sleep */
+			DECLARE_WAITQUEUE(wait, current);
+
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&chip->wq, &wait);
+			mutex_unlock(&chip->mutex);
+			schedule();
+			remove_wait_queue(&chip->wq, &wait);
+			timeo = jiffies + (HZ / 2); /* FIXME */
+			mutex_lock(&chip->mutex);
+			continue;
+		}
+
+		/*
+		 * We check "time_after" and "!chip_good" before checking
+		 * "chip_good" to avoid the failure due to scheduling.
+		 */
+		if (time_after(jiffies, timeo) &&
+		    !chip_good(map, chip, adr, &datum)) {
+			pr_err("MTD %s(): software timeout, address:0x%.8lx.\n",
+			       __func__, adr);
+			ret = -EIO;
+			break;
+		}
+
+		if (chip_good(map, chip, adr, &datum)) {
+			if (cfi_check_err_status(map, chip, adr))
+				ret = -EIO;
+			break;
+		}
+
+		/* Latency issues. Drop the lock, wait a while and retry */
+		UDELAY(map, chip, adr, 1);
+	}
+
+	return ret;
+}
+
+static void __xipram do_write_buffer_reset(struct map_info *map,
+					   struct flchip *chip,
+					   struct cfi_private *cfi)
+{
+	/*
+	 * Recovery from write-buffer programming failures requires
+	 * the write-to-buffer-reset sequence.  Since the last part
+	 * of the sequence also works as a normal reset, we can run
+	 * the same commands regardless of why we are here.
+	 * See e.g.
+	 * http://www.spansion.com/Support/Application%20Notes/MirrorBit_Write_Buffer_Prog_Page_Buffer_Read_AN.pdf
+	 */
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xF0, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+
+	/* FIXME - should have reset delay before continuing */
+}
+
+/*
+ * FIXME: interleaved mode not tested, and probably not supported!
+ */
+static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
+				    unsigned long adr, const u_char *buf,
+				    int len)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret;
+	unsigned long cmd_adr;
+	int z, words;
+	map_word datum;
+
+	adr += chip->start;
+	cmd_adr = adr;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr, FL_WRITING);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	datum = map_word_load(map, buf);
+
+	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n",
+		 __func__, adr, datum.x[0]);
+
+	XIP_INVAL_CACHED_RANGE(map, adr, len);
+	ENABLE_VPP(map);
+	xip_disable(map, chip, cmd_adr);
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+
+	/* Write Buffer Load */
+	map_write(map, CMD(0x25), cmd_adr);
+
+	chip->state = FL_WRITING_TO_BUFFER;
+
+	/* Write length of data to come */
+	words = len / map_bankwidth(map);
+	map_write(map, CMD(words - 1), cmd_adr);
+	/* Write data */
+	z = 0;
+	while(z < words * map_bankwidth(map)) {
+		datum = map_word_load(map, buf);
+		map_write(map, datum, adr + z);
+
+		z += map_bankwidth(map);
+		buf += map_bankwidth(map);
+	}
+	z -= map_bankwidth(map);
+
+	adr += z;
+
+	/* Write Buffer Program Confirm: GO GO GO */
+	map_write(map, CMD(0x29), cmd_adr);
+	chip->state = FL_WRITING;
+
+	INVALIDATE_CACHE_UDELAY(map, chip,
+				adr, map_bankwidth(map),
+				chip->word_write_time);
+
+	ret = do_write_buffer_wait(map, chip, adr, datum);
+	if (ret)
+		do_write_buffer_reset(map, chip, cfi);
+
+	xip_enable(map, chip, adr);
+
+	chip->state = FL_READY;
+	DISABLE_VPP(map);
+	put_chip(map, chip, adr);
+	mutex_unlock(&chip->mutex);
+
+	return ret;
+}
+
+
+static int cfi_amdstd_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
+				    size_t *retlen, const u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int wbufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
+	int ret;
+	int chipnum;
+	unsigned long ofs;
+
+	chipnum = to >> cfi->chipshift;
+	ofs = to  - (chipnum << cfi->chipshift);
+
+	/* If it's not bus-aligned, do the first word write */
+	if (ofs & (map_bankwidth(map)-1)) {
+		size_t local_len = (-ofs)&(map_bankwidth(map)-1);
+		if (local_len > len)
+			local_len = len;
+		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
+					     local_len, retlen, buf);
+		if (ret)
+			return ret;
+		ofs += local_len;
+		buf += local_len;
+		len -= local_len;
+
+		if (ofs >> cfi->chipshift) {
+			chipnum ++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+		}
+	}
+
+	/* Write buffer is worth it only if more than one word to write... */
+	while (len >= map_bankwidth(map) * 2) {
+		/* We must not cross write block boundaries */
+		int size = wbufsize - (ofs & (wbufsize-1));
+
+		if (size > len)
+			size = len;
+		if (size % map_bankwidth(map))
+			size -= size % map_bankwidth(map);
+
+		ret = do_write_buffer(map, &cfi->chips[chipnum],
+				      ofs, buf, size);
+		if (ret)
+			return ret;
+
+		ofs += size;
+		buf += size;
+		(*retlen) += size;
+		len -= size;
+
+		if (ofs >> cfi->chipshift) {
+			chipnum ++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+		}
+	}
+
+	if (len) {
+		size_t retlen_dregs = 0;
+
+		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
+					     len, &retlen_dregs, buf);
+
+		*retlen += retlen_dregs;
+		return ret;
+	}
+
+	return 0;
+}
+#endif /* !FORCE_WORD_WRITE */
+
+/*
+ * Wait for the flash chip to become ready to write data
+ *
+ * This is only called during the panic_write() path. When panic_write()
+ * is called, the kernel is in the process of a panic, and will soon be
+ * dead. Therefore we don't take any locks, and attempt to get access
+ * to the chip as soon as possible.
+ */
+static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
+				 unsigned long adr)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	int retries = 10;
+	int i;
+
+	/*
+	 * If the driver thinks the chip is idle, and no toggle bits
+	 * are changing, then the chip is actually idle for sure.
+	 */
+	if (chip->state == FL_READY && chip_ready(map, chip, adr, NULL))
+		return 0;
+
+	/*
+	 * Try several times to reset the chip and then wait for it
+	 * to become idle. The upper limit of a few milliseconds of
+	 * delay isn't a big problem: the kernel is dying anyway. It
+	 * is more important to save the messages.
+	 */
+	while (retries > 0) {
+		const unsigned long timeo = (HZ / 1000) + 1;
+
+		/* send the reset command */
+		map_write(map, CMD(0xF0), chip->start);
+
+		/* wait for the chip to become ready */
+		for (i = 0; i < jiffies_to_usecs(timeo); i++) {
+			if (chip_ready(map, chip, adr, NULL))
+				return 0;
+
+			udelay(1);
+		}
+
+		retries--;
+	}
+
+	/* the chip never became ready */
+	return -EBUSY;
+}
+
+/*
+ * Write out one word of data to a single flash chip during a kernel panic
+ *
+ * This is only called during the panic_write() path. When panic_write()
+ * is called, the kernel is in the process of a panic, and will soon be
+ * dead. Therefore we don't take any locks, and attempt to get access
+ * to the chip as soon as possible.
+ *
+ * The implementation of this routine is intentionally similar to
+ * do_write_oneword(), in order to ease code maintenance.
+ */
+static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
+				  unsigned long adr, map_word datum)
+{
+	const unsigned long uWriteTimeout = (HZ / 1000) + 1;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int retry_cnt = 0;
+	map_word oldd;
+	int ret;
+	int i;
+
+	adr += chip->start;
+
+	ret = cfi_amdstd_panic_wait(map, chip, adr);
+	if (ret)
+		return ret;
+
+	pr_debug("MTD %s(): PANIC WRITE 0x%.8lx(0x%.8lx)\n",
+			__func__, adr, datum.x[0]);
+
+	/*
+	 * Check for a NOP for the case when the datum to write is already
+	 * present - it saves time and works around buggy chips that corrupt
+	 * data at other locations when 0xff is written to a location that
+	 * already contains 0xff.
+	 */
+	oldd = map_read(map, adr);
+	if (map_word_equal(map, oldd, datum)) {
+		pr_debug("MTD %s(): NOP\n", __func__);
+		goto op_done;
+	}
+
+	ENABLE_VPP(map);
+
+retry:
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	map_write(map, datum, adr);
+
+	for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
+		if (chip_ready(map, chip, adr, NULL))
+			break;
+
+		udelay(1);
+	}
+
+	if (!chip_ready(map, chip, adr, &datum) ||
+	    cfi_check_err_status(map, chip, adr)) {
+		/* reset on all failures. */
+		map_write(map, CMD(0xF0), chip->start);
+		/* FIXME - should have reset delay before continuing */
+
+		if (++retry_cnt <= MAX_RETRIES)
+			goto retry;
+
+		ret = -EIO;
+	}
+
+op_done:
+	DISABLE_VPP(map);
+	return ret;
+}
+
+/*
+ * Write out some data during a kernel panic
+ *
+ * This is used by the mtdoops driver to save the dying messages from a
+ * kernel which has panic'd.
+ *
+ * This routine ignores all of the locking used throughout the rest of the
+ * driver, in order to ensure that the data gets written out no matter what
+ * state this driver (and the flash chip itself) was in when the kernel crashed.
+ *
+ * The implementation of this routine is intentionally similar to
+ * cfi_amdstd_write_words(), in order to ease code maintenance.
+ */
+static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
+				  size_t *retlen, const u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long ofs, chipstart;
+	int ret;
+	int chipnum;
+
+	chipnum = to >> cfi->chipshift;
+	ofs = to - (chipnum << cfi->chipshift);
+	chipstart = cfi->chips[chipnum].start;
+
+	/* If it's not bus aligned, do the first byte write */
+	if (ofs & (map_bankwidth(map) - 1)) {
+		unsigned long bus_ofs = ofs & ~(map_bankwidth(map) - 1);
+		int i = ofs - bus_ofs;
+		int n = 0;
+		map_word tmp_buf;
+
+		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], bus_ofs);
+		if (ret)
+			return ret;
+
+		/* Load 'tmp_buf' with old contents of flash */
+		tmp_buf = map_read(map, bus_ofs + chipstart);
+
+		/* Number of bytes to copy from buffer */
+		n = min_t(int, len, map_bankwidth(map) - i);
+
+		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
+
+		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
+					     bus_ofs, tmp_buf);
+		if (ret)
+			return ret;
+
+		ofs += n;
+		buf += n;
+		(*retlen) += n;
+		len -= n;
+
+		if (ofs >> cfi->chipshift) {
+			chipnum++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+		}
+	}
+
+	/* We are now aligned, write as much as possible */
+	while (len >= map_bankwidth(map)) {
+		map_word datum;
+
+		datum = map_word_load(map, buf);
+
+		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
+					     ofs, datum);
+		if (ret)
+			return ret;
+
+		ofs += map_bankwidth(map);
+		buf += map_bankwidth(map);
+		(*retlen) += map_bankwidth(map);
+		len -= map_bankwidth(map);
+
+		if (ofs >> cfi->chipshift) {
+			chipnum++;
+			ofs = 0;
+			if (chipnum == cfi->numchips)
+				return 0;
+
+			chipstart = cfi->chips[chipnum].start;
+		}
+	}
+
+	/* Write the trailing bytes if any */
+	if (len & (map_bankwidth(map) - 1)) {
+		map_word tmp_buf;
+
+		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], ofs);
+		if (ret)
+			return ret;
+
+		tmp_buf = map_read(map, ofs + chipstart);
+
+		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
+
+		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
+					     ofs, tmp_buf);
+		if (ret)
+			return ret;
+
+		(*retlen) += len;
+	}
+
+	return 0;
+}
+
+
+/*
+ * Handle devices with one erase region, that only implement
+ * the chip erase command.
+ */
+static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long timeo = jiffies + HZ;
+	unsigned long int adr;
+	DECLARE_WAITQUEUE(wait, current);
+	int ret;
+	int retry_cnt = 0;
+	map_word datum = map_word_ff(map);
+
+	adr = cfi->addr_unlock1;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr, FL_ERASING);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
+	       __func__, chip->start);
+
+	XIP_INVAL_CACHED_RANGE(map, adr, map->size);
+	ENABLE_VPP(map);
+	xip_disable(map, chip, adr);
+
+ retry:
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x10, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+
+	chip->state = FL_ERASING;
+	chip->erase_suspended = 0;
+	chip->in_progress_block_addr = adr;
+	chip->in_progress_block_mask = ~(map->size - 1);
+
+	INVALIDATE_CACHE_UDELAY(map, chip,
+				adr, map->size,
+				chip->erase_time*500);
+
+	timeo = jiffies + (HZ*20);
+
+	for (;;) {
+		if (chip->state != FL_ERASING) {
+			/* Someone's suspended the erase. Sleep */
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&chip->wq, &wait);
+			mutex_unlock(&chip->mutex);
+			schedule();
+			remove_wait_queue(&chip->wq, &wait);
+			mutex_lock(&chip->mutex);
+			continue;
+		}
+		if (chip->erase_suspended) {
+			/* This erase was suspended and resumed.
+			   Adjust the timeout */
+			timeo = jiffies + (HZ*20); /* FIXME */
+			chip->erase_suspended = 0;
+		}
+
+		if (chip_ready(map, chip, adr, &datum)) {
+			if (cfi_check_err_status(map, chip, adr))
+				ret = -EIO;
+			break;
+		}
+
+		if (time_after(jiffies, timeo)) {
+			printk(KERN_WARNING "MTD %s(): software timeout\n",
+			       __func__);
+			ret = -EIO;
+			break;
+		}
+
+		/* Latency issues. Drop the lock, wait a while and retry */
+		UDELAY(map, chip, adr, 1000000/HZ);
+	}
+	/* Did we succeed? */
+	if (ret) {
+		/* reset on all failures. */
+		map_write(map, CMD(0xF0), chip->start);
+		/* FIXME - should have reset delay before continuing */
+
+		if (++retry_cnt <= MAX_RETRIES) {
+			ret = 0;
+			goto retry;
+		}
+	}
+
+	chip->state = FL_READY;
+	xip_enable(map, chip, adr);
+	DISABLE_VPP(map);
+	put_chip(map, chip, adr);
+	mutex_unlock(&chip->mutex);
+
+	return ret;
+}
+
+
+static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip, unsigned long adr, int len, void *thunk)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long timeo = jiffies + HZ;
+	DECLARE_WAITQUEUE(wait, current);
+	int ret;
+	int retry_cnt = 0;
+	map_word datum = map_word_ff(map);
+
+	adr += chip->start;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr, FL_ERASING);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
+		 __func__, adr);
+
+	XIP_INVAL_CACHED_RANGE(map, adr, len);
+	ENABLE_VPP(map);
+	xip_disable(map, chip, adr);
+
+ retry:
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
+	map_write(map, cfi->sector_erase_cmd, adr);
+
+	chip->state = FL_ERASING;
+	chip->erase_suspended = 0;
+	chip->in_progress_block_addr = adr;
+	chip->in_progress_block_mask = ~(len - 1);
+
+	INVALIDATE_CACHE_UDELAY(map, chip,
+				adr, len,
+				chip->erase_time*500);
+
+	timeo = jiffies + (HZ*20);
+
+	for (;;) {
+		if (chip->state != FL_ERASING) {
+			/* Someone's suspended the erase. Sleep */
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&chip->wq, &wait);
+			mutex_unlock(&chip->mutex);
+			schedule();
+			remove_wait_queue(&chip->wq, &wait);
+			mutex_lock(&chip->mutex);
+			continue;
+		}
+		if (chip->erase_suspended) {
+			/* This erase was suspended and resumed.
+			   Adjust the timeout */
+			timeo = jiffies + (HZ*20); /* FIXME */
+			chip->erase_suspended = 0;
+		}
+
+		if (chip_ready(map, chip, adr, &datum)) {
+			if (cfi_check_err_status(map, chip, adr))
+				ret = -EIO;
+			break;
+		}
+
+		if (time_after(jiffies, timeo)) {
+			printk(KERN_WARNING "MTD %s(): software timeout\n",
+			       __func__);
+			ret = -EIO;
+			break;
+		}
+
+		/* Latency issues. Drop the lock, wait a while and retry */
+		UDELAY(map, chip, adr, 1000000/HZ);
+	}
+	/* Did we succeed? */
+	if (ret) {
+		/* reset on all failures. */
+		map_write(map, CMD(0xF0), chip->start);
+		/* FIXME - should have reset delay before continuing */
+
+		if (++retry_cnt <= MAX_RETRIES) {
+			ret = 0;
+			goto retry;
+		}
+	}
+
+	chip->state = FL_READY;
+	xip_enable(map, chip, adr);
+	DISABLE_VPP(map);
+	put_chip(map, chip, adr);
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+
+static int cfi_amdstd_erase_varsize(struct mtd_info *mtd, struct erase_info *instr)
+{
+	return cfi_varsize_frob(mtd, do_erase_oneblock, instr->addr,
+				instr->len, NULL);
+}
+
+
+static int cfi_amdstd_erase_chip(struct mtd_info *mtd, struct erase_info *instr)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	if (instr->addr != 0)
+		return -EINVAL;
+
+	if (instr->len != mtd->size)
+		return -EINVAL;
+
+	return do_erase_chip(map, &cfi->chips[0]);
+}
+
+static int do_atmel_lock(struct map_info *map, struct flchip *chip,
+			 unsigned long adr, int len, void *thunk)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr + chip->start, FL_LOCKING);
+	if (ret)
+		goto out_unlock;
+	chip->state = FL_LOCKING;
+
+	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	map_write(map, CMD(0x40), chip->start + adr);
+
+	chip->state = FL_READY;
+	put_chip(map, chip, adr + chip->start);
+	ret = 0;
+
+out_unlock:
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+static int do_atmel_unlock(struct map_info *map, struct flchip *chip,
+			   unsigned long adr, int len, void *thunk)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	int ret;
+
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr + chip->start, FL_UNLOCKING);
+	if (ret)
+		goto out_unlock;
+	chip->state = FL_UNLOCKING;
+
+	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	map_write(map, CMD(0x70), adr);
+
+	chip->state = FL_READY;
+	put_chip(map, chip, adr + chip->start);
+	ret = 0;
+
+out_unlock:
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+	return cfi_varsize_frob(mtd, do_atmel_lock, ofs, len, NULL);
+}
+
+static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+	return cfi_varsize_frob(mtd, do_atmel_unlock, ofs, len, NULL);
+}
+
+/*
+ * Advanced Sector Protection - PPB (Persistent Protection Bit) locking
+ */
+
+struct ppb_lock {
+	struct flchip *chip;
+	unsigned long adr;
+	int locked;
+};
+
+#define DO_XXLOCK_ONEBLOCK_LOCK		((void *)1)
+#define DO_XXLOCK_ONEBLOCK_UNLOCK	((void *)2)
+#define DO_XXLOCK_ONEBLOCK_GETLOCK	((void *)3)
+
+static int __maybe_unused do_ppb_xxlock(struct map_info *map,
+					struct flchip *chip,
+					unsigned long adr, int len, void *thunk)
+{
+	struct cfi_private *cfi = map->fldrv_priv;
+	unsigned long timeo;
+	int ret;
+
+	adr += chip->start;
+	mutex_lock(&chip->mutex);
+	ret = get_chip(map, chip, adr, FL_LOCKING);
+	if (ret) {
+		mutex_unlock(&chip->mutex);
+		return ret;
+	}
+
+	pr_debug("MTD %s(): XXLOCK 0x%08lx len %d\n", __func__, adr, len);
+
+	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+	/* PPB entry command */
+	cfi_send_gen_cmd(0xC0, cfi->addr_unlock1, chip->start, map, cfi,
+			 cfi->device_type, NULL);
+
+	if (thunk == DO_XXLOCK_ONEBLOCK_LOCK) {
+		chip->state = FL_LOCKING;
+		map_write(map, CMD(0xA0), adr);
+		map_write(map, CMD(0x00), adr);
+	} else if (thunk == DO_XXLOCK_ONEBLOCK_UNLOCK) {
+		/*
+		 * Unlocking of one specific sector is not supported, so we
+		 * have to unlock all sectors of this device instead
+		 */
+		chip->state = FL_UNLOCKING;
+		map_write(map, CMD(0x80), chip->start);
+		map_write(map, CMD(0x30), chip->start);
+	} else if (thunk == DO_XXLOCK_ONEBLOCK_GETLOCK) {
+		chip->state = FL_JEDEC_QUERY;
+		/* Return locked status: 0->locked, 1->unlocked */
+		ret = !cfi_read_query(map, adr);
+	} else
+		BUG();
+
+	/*
+	 * Wait for some time as unlocking of all sectors takes quite long
+	 */
+	timeo = jiffies + msecs_to_jiffies(2000);	/* 2s max (un)locking */
+	for (;;) {
+		if (chip_ready(map, chip, adr, NULL))
+			break;
+
+		if (time_after(jiffies, timeo)) {
+			printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
+			ret = -EIO;
+			break;
+		}
+
+		UDELAY(map, chip, adr, 1);
+	}
+
+	/* Exit BC commands */
+	map_write(map, CMD(0x90), chip->start);
+	map_write(map, CMD(0x00), chip->start);
+
+	chip->state = FL_READY;
+	put_chip(map, chip, adr);
+	mutex_unlock(&chip->mutex);
+
+	return ret;
+}
+
+static int __maybe_unused cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs,
+				       uint64_t len)
+{
+	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+				DO_XXLOCK_ONEBLOCK_LOCK);
+}
+
+static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
+					 uint64_t len)
+{
+	struct mtd_erase_region_info *regions = mtd->eraseregions;
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	struct ppb_lock *sect;
+	unsigned long adr;
+	loff_t offset;
+	uint64_t length;
+	int chipnum;
+	int i;
+	int sectors;
+	int ret;
+	int max_sectors;
+
+	/*
+	 * PPB unlocking always unlocks all sectors of the flash chip.
+	 * We need to re-lock all previously locked sectors. So lets
+	 * first check the locking status of all sectors and save
+	 * it for future use.
+	 */
+	max_sectors = 0;
+	for (i = 0; i < mtd->numeraseregions; i++)
+		max_sectors += regions[i].numblocks;
+
+	sect = kcalloc(max_sectors, sizeof(struct ppb_lock), GFP_KERNEL);
+	if (!sect)
+		return -ENOMEM;
+
+	/*
+	 * This code to walk all sectors is a slightly modified version
+	 * of the cfi_varsize_frob() code.
+	 */
+	i = 0;
+	chipnum = 0;
+	adr = 0;
+	sectors = 0;
+	offset = 0;
+	length = mtd->size;
+
+	while (length) {
+		int size = regions[i].erasesize;
+
+		/*
+		 * Only test sectors that shall not be unlocked. The other
+		 * sectors shall be unlocked, so lets keep their locking
+		 * status at "unlocked" (locked=0) for the final re-locking.
+		 */
+		if ((offset < ofs) || (offset >= (ofs + len))) {
+			sect[sectors].chip = &cfi->chips[chipnum];
+			sect[sectors].adr = adr;
+			sect[sectors].locked = do_ppb_xxlock(
+				map, &cfi->chips[chipnum], adr, 0,
+				DO_XXLOCK_ONEBLOCK_GETLOCK);
+		}
+
+		adr += size;
+		offset += size;
+		length -= size;
+
+		if (offset == regions[i].offset + size * regions[i].numblocks)
+			i++;
+
+		if (adr >> cfi->chipshift) {
+			if (offset >= (ofs + len))
+				break;
+			adr = 0;
+			chipnum++;
+
+			if (chipnum >= cfi->numchips)
+				break;
+		}
+
+		sectors++;
+		if (sectors >= max_sectors) {
+			printk(KERN_ERR "Only %d sectors for PPB locking supported!\n",
+			       max_sectors);
+			kfree(sect);
+			return -EINVAL;
+		}
+	}
+
+	/* Now unlock the whole chip */
+	ret = cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+			       DO_XXLOCK_ONEBLOCK_UNLOCK);
+	if (ret) {
+		kfree(sect);
+		return ret;
+	}
+
+	/*
+	 * PPB unlocking always unlocks all sectors of the flash chip.
+	 * We need to re-lock all previously locked sectors.
+	 */
+	for (i = 0; i < sectors; i++) {
+		if (sect[i].locked)
+			do_ppb_xxlock(map, sect[i].chip, sect[i].adr, 0,
+				      DO_XXLOCK_ONEBLOCK_LOCK);
+	}
+
+	kfree(sect);
+	return ret;
+}
+
+static int __maybe_unused cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs,
+					    uint64_t len)
+{
+	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
+				DO_XXLOCK_ONEBLOCK_GETLOCK) ? 1 : 0;
+}
+
+static void cfi_amdstd_sync (struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int i;
+	struct flchip *chip;
+	int ret = 0;
+	DECLARE_WAITQUEUE(wait, current);
+
+	for (i=0; !ret && i<cfi->numchips; i++) {
+		chip = &cfi->chips[i];
+
+	retry:
+		mutex_lock(&chip->mutex);
+
+		switch(chip->state) {
+		case FL_READY:
+		case FL_STATUS:
+		case FL_CFI_QUERY:
+		case FL_JEDEC_QUERY:
+			chip->oldstate = chip->state;
+			chip->state = FL_SYNCING;
+			/* No need to wake_up() on this state change -
+			 * as the whole point is that nobody can do anything
+			 * with the chip now anyway.
+			 */
+			fallthrough;
+		case FL_SYNCING:
+			mutex_unlock(&chip->mutex);
+			break;
+
+		default:
+			/* Not an idle state */
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			add_wait_queue(&chip->wq, &wait);
+
+			mutex_unlock(&chip->mutex);
+
+			schedule();
+
+			remove_wait_queue(&chip->wq, &wait);
+
+			goto retry;
+		}
+	}
+
+	/* Unlock the chips again */
+
+	for (i--; i >=0; i--) {
+		chip = &cfi->chips[i];
+
+		mutex_lock(&chip->mutex);
+
+		if (chip->state == FL_SYNCING) {
+			chip->state = chip->oldstate;
+			wake_up(&chip->wq);
+		}
+		mutex_unlock(&chip->mutex);
+	}
+}
+
+
+static int cfi_amdstd_suspend(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int i;
+	struct flchip *chip;
+	int ret = 0;
+
+	for (i=0; !ret && i<cfi->numchips; i++) {
+		chip = &cfi->chips[i];
+
+		mutex_lock(&chip->mutex);
+
+		switch(chip->state) {
+		case FL_READY:
+		case FL_STATUS:
+		case FL_CFI_QUERY:
+		case FL_JEDEC_QUERY:
+			chip->oldstate = chip->state;
+			chip->state = FL_PM_SUSPENDED;
+			/* No need to wake_up() on this state change -
+			 * as the whole point is that nobody can do anything
+			 * with the chip now anyway.
+			 */
+		case FL_PM_SUSPENDED:
+			break;
+
+		default:
+			ret = -EAGAIN;
+			break;
+		}
+		mutex_unlock(&chip->mutex);
+	}
+
+	/* Unlock the chips again */
+
+	if (ret) {
+		for (i--; i >=0; i--) {
+			chip = &cfi->chips[i];
+
+			mutex_lock(&chip->mutex);
+
+			if (chip->state == FL_PM_SUSPENDED) {
+				chip->state = chip->oldstate;
+				wake_up(&chip->wq);
+			}
+			mutex_unlock(&chip->mutex);
+		}
+	}
+
+	return ret;
+}
+
+
+static void cfi_amdstd_resume(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int i;
+	struct flchip *chip;
+
+	for (i=0; i<cfi->numchips; i++) {
+
+		chip = &cfi->chips[i];
+
+		mutex_lock(&chip->mutex);
+
+		if (chip->state == FL_PM_SUSPENDED) {
+			chip->state = FL_READY;
+			map_write(map, CMD(0xF0), chip->start);
+			wake_up(&chip->wq);
+		}
+		else
+			printk(KERN_ERR "Argh. Chip not in PM_SUSPENDED state upon resume()\n");
+
+		mutex_unlock(&chip->mutex);
+	}
+}
+
+
+/*
+ * Ensure that the flash device is put back into read array mode before
+ * unloading the driver or rebooting.  On some systems, rebooting while
+ * the flash is in query/program/erase mode will prevent the CPU from
+ * fetching the bootloader code, requiring a hard reset or power cycle.
+ */
+static int cfi_amdstd_reset(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+	int i, ret;
+	struct flchip *chip;
+
+	for (i = 0; i < cfi->numchips; i++) {
+
+		chip = &cfi->chips[i];
+
+		mutex_lock(&chip->mutex);
+
+		ret = get_chip(map, chip, chip->start, FL_SHUTDOWN);
+		if (!ret) {
+			map_write(map, CMD(0xF0), chip->start);
+			chip->state = FL_SHUTDOWN;
+			put_chip(map, chip, chip->start);
+		}
+
+		mutex_unlock(&chip->mutex);
+	}
+
+	return 0;
+}
+
+
+static int cfi_amdstd_reboot(struct notifier_block *nb, unsigned long val,
+			       void *v)
+{
+	struct mtd_info *mtd;
+
+	mtd = container_of(nb, struct mtd_info, reboot_notifier);
+	cfi_amdstd_reset(mtd);
+	return NOTIFY_DONE;
+}
+
+
+static void cfi_amdstd_destroy(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	cfi_amdstd_reset(mtd);
+	unregister_reboot_notifier(&mtd->reboot_notifier);
+	kfree(cfi->cmdset_priv);
+	kfree(cfi->cfiq);
+	kfree(cfi);
+	kfree(mtd->eraseregions);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Crossnet Co. <info@crossnet.co.jp> et al.");
+MODULE_DESCRIPTION("MTD chip driver for AMD/Fujitsu flash chips");
+MODULE_ALIAS("cfi_cmdset_0006");
+MODULE_ALIAS("cfi_cmdset_0701");