path: root/drivers/mtd/chips/cfi_probe.c

/*
   Common Flash Interface probe code.
   (C) 2000 Red Hat. GPL'd.
*/

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/byteorder.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/interrupt.h>

#include <linux/mtd/xip.h>
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/gen_probe.h>

//#define DEBUG_CFI

#ifdef DEBUG_CFI
static void print_cfi_ident(struct cfi_ident *);
#endif

static int cfi_probe_chip(struct map_info *map, __u32 base,
			  unsigned long *chip_map, struct cfi_private *cfi);
static int cfi_chip_setup(struct map_info *map, struct cfi_private *cfi);

struct mtd_info *cfi_probe(struct map_info *map);

#ifdef CONFIG_MTD_XIP

/* only needed for short periods, so this is rather simple */
#define xip_disable()	local_irq_disable()

#define xip_allowed(base, map) \
do { \
	(void) map_read(map, base); \
	xip_iprefetch(); \
	local_irq_enable(); \
} while (0)

#define xip_enable(base, map, cfi) \
do { \
	cfi_qry_mode_off(base, map, cfi);		\
	xip_allowed(base, map); \
} while (0)

#define xip_disable_qry(base, map, cfi) \
do { \
	xip_disable(); \
	cfi_qry_mode_on(base, map, cfi); \
} while (0)

#else

#define xip_disable()			do { } while (0)
#define xip_allowed(base, map)		do { } while (0)
#define xip_enable(base, map, cfi)	do { } while (0)
#define xip_disable_qry(base, map, cfi) do { } while (0)

#endif

/*
 * This fixup occurs immediately after reading the CFI structure and can affect
 * the number of chips detected, unlike cfi_fixup, which occurs after an
 * mtd_info structure has been created for the chip.
 */
struct cfi_early_fixup {
	uint16_t mfr;
	uint16_t id;
	void (*fixup)(struct cfi_private *cfi);
};

static void cfi_early_fixup(struct cfi_private *cfi,
			    const struct cfi_early_fixup *fixups)
{
	const struct cfi_early_fixup *f;

	for (f = fixups; f->fixup; f++) {
		if (((f->mfr == CFI_MFR_ANY) || (f->mfr == cfi->mfr)) &&
		    ((f->id == CFI_ID_ANY) || (f->id == cfi->id))) {
			f->fixup(cfi);
		}
	}
}

/* check for QRY.
   in: interleave,type,mode
   ret: table index, <0 for error
 */

static int __xipram cfi_probe_chip(struct map_info *map, __u32 base,
				   unsigned long *chip_map, struct cfi_private *cfi)
{
	int i;

	if ((base + 0) >= map->size) {
		printk(KERN_NOTICE
			"Probe at base[0x00](0x%08lx) past the end of the map(0x%08lx)\n",
			(unsigned long)base, map->size -1);
		return 0;
	}
	if ((base + 0xff) >= map->size) {
		printk(KERN_NOTICE
			"Probe at base[0x55](0x%08lx) past the end of the map(0x%08lx)\n",
			(unsigned long)base + 0x55, map->size -1);
		return 0;
	}

	xip_disable();
	if (!cfi_qry_mode_on(base, map, cfi)) {
		xip_enable(base, map, cfi);
		return 0;
	}

	if (!cfi->numchips) {
		/* This is the first time we're called. Set up the CFI
		   stuff accordingly and return */
		return cfi_chip_setup(map, cfi);
	}

	/* Check each previous chip to see if it's an alias */
 	for (i=0; i < (base >> cfi->chipshift); i++) {
 		unsigned long start;
 		if(!test_bit(i, chip_map)) {
			/* Skip location; no valid chip at this address */
 			continue;
 		}
 		start = i << cfi->chipshift;
		/* This chip should be in read mode if it's one
		   we've already touched. */
		if (cfi_qry_present(map, start, cfi)) {
			/* Eep. This chip also had the QRY marker.
			 * Is it an alias for the new one? */
			cfi_qry_mode_off(start, map, cfi);

			/* If the QRY marker goes away, it's an alias */
			if (!cfi_qry_present(map, start, cfi)) {
				xip_allowed(base, map);
				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
				       map->name, base, start);
				return 0;
			}
			/* Yes, it's actually got QRY for data. Most
			 * unfortunate. Stick the new chip in read mode
			 * too and if it's the same, assume it's an alias. */
			/* FIXME: Use other modes to do a proper check */
			cfi_qry_mode_off(base, map, cfi);

			if (cfi_qry_present(map, base, cfi)) {
				xip_allowed(base, map);
				printk(KERN_DEBUG "%s: Found an alias at 0x%x for the chip at 0x%lx\n",
				       map->name, base, start);
				return 0;
			}
		}
	}

	/* OK, if we got to here, then none of the previous chips appear to
	   be aliases for the current one. */
	set_bit((base >> cfi->chipshift), chip_map); /* Update chip map */
	cfi->numchips++;

	/* Put it back into Read Mode */
	cfi_qry_mode_off(base, map, cfi);
	xip_allowed(base, map);

	printk(KERN_INFO "%s: Found %d x%d devices at 0x%x in %d-bit bank\n",
	       map->name, cfi->interleave, cfi->device_type*8, base,
	       map->bankwidth*8);

	return 1;
}

static void fixup_s70gl02gs_chips(struct cfi_private *cfi)
{
	/*
	 * S70GL02GS flash reports a single 256 MiB chip, but is really made up
	 * of two 128 MiB chips with 1024 sectors each.
	 */
	cfi->cfiq->DevSize = 27;
	cfi->cfiq->EraseRegionInfo[0] = 0x20003ff;
	pr_warn("Bad S70GL02GS CFI data; adjust to detect 2 chips\n");
}

static const struct cfi_early_fixup cfi_early_fixup_table[] = {
	{ CFI_MFR_AMD, 0x4801, fixup_s70gl02gs_chips },
	{ },
};

static int __xipram cfi_chip_setup(struct map_info *map,
				   struct cfi_private *cfi)
{
	int ofs_factor = cfi->interleave*cfi->device_type;
	__u32 base = 0;
	int num_erase_regions = cfi_read_query(map, base + (0x10 + 28)*ofs_factor);
	int i;
	int addr_unlock1 = 0x555, addr_unlock2 = 0x2AA;

	xip_enable(base, map, cfi);
#ifdef DEBUG_CFI
	printk("Number of erase regions: %d\n", num_erase_regions);
#endif
	if (!num_erase_regions)
		return 0;

	cfi->cfiq = kmalloc(sizeof(struct cfi_ident) + num_erase_regions * 4, GFP_KERNEL);
	if (!cfi->cfiq)
		return 0;

	memset(cfi->cfiq,0,sizeof(struct cfi_ident));

	cfi->cfi_mode = CFI_MODE_CFI;

	cfi->sector_erase_cmd = CMD(0x30);

	/* Read the CFI info structure */
	xip_disable_qry(base, map, cfi);
	for (i=0; i<(sizeof(struct cfi_ident) + num_erase_regions * 4); i++)
		((unsigned char *)cfi->cfiq)[i] = cfi_read_query(map,base + (0x10 + i)*ofs_factor);

	/* Do any necessary byteswapping */
	cfi->cfiq->P_ID = le16_to_cpu(cfi->cfiq->P_ID);

	cfi->cfiq->P_ADR = le16_to_cpu(cfi->cfiq->P_ADR);
	cfi->cfiq->A_ID = le16_to_cpu(cfi->cfiq->A_ID);
	cfi->cfiq->A_ADR = le16_to_cpu(cfi->cfiq->A_ADR);
	cfi->cfiq->InterfaceDesc = le16_to_cpu(cfi->cfiq->InterfaceDesc);
	cfi->cfiq->MaxBufWriteSize = le16_to_cpu(cfi->cfiq->MaxBufWriteSize);

#ifdef DEBUG_CFI
	/* Dump the information therein */
	print_cfi_ident(cfi->cfiq);
#endif

	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
		cfi->cfiq->EraseRegionInfo[i] = le32_to_cpu(cfi->cfiq->EraseRegionInfo[i]);

#ifdef DEBUG_CFI
		printk("  Erase Region #%d: BlockSize 0x%4.4X bytes, %d blocks\n",
		       i, (cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff,
		       (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1);
#endif
	}

	if (cfi->cfiq->P_ID == P_ID_SST_OLD) {
		addr_unlock1 = 0x5555;
		addr_unlock2 = 0x2AAA;
	}

	/*
	 * Note we put the device back into Read Mode BEFORE going into Auto
	 * Select Mode, as some devices support nes