diff options
Diffstat (limited to 'drivers/mtd/chips/jedec.c')
| -rw-r--r-- | drivers/mtd/chips/jedec.c | 934 |
1 files changed, 934 insertions, 0 deletions
diff --git a/drivers/mtd/chips/jedec.c b/drivers/mtd/chips/jedec.c new file mode 100644 index 00000000000..62d235a9a4e --- /dev/null +++ b/drivers/mtd/chips/jedec.c @@ -0,0 +1,934 @@ + +/* JEDEC Flash Interface. + * This is an older type of interface for self programming flash. It is + * commonly use in older AMD chips and is obsolete compared with CFI. + * It is called JEDEC because the JEDEC association distributes the ID codes + * for the chips. + * + * See the AMD flash databook for information on how to operate the interface. + * + * This code does not support anything wider than 8 bit flash chips, I am + * not going to guess how to send commands to them, plus I expect they will + * all speak CFI.. + * + * $Id: jedec.c,v 1.22 2005/01/05 18:05:11 dwmw2 Exp $ + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/mtd/jedec.h> +#include <linux/mtd/map.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/compatmac.h> + +static struct mtd_info *jedec_probe(struct map_info *); +static int jedec_probe8(struct map_info *map,unsigned long base, + struct jedec_private *priv); +static int jedec_probe16(struct map_info *map,unsigned long base, + struct jedec_private *priv); +static int jedec_probe32(struct map_info *map,unsigned long base, + struct jedec_private *priv); +static void jedec_flash_chip_scan(struct jedec_private *priv,unsigned long start, + unsigned long len); +static int flash_erase(struct mtd_info *mtd, struct erase_info *instr); +static int flash_write(struct mtd_info *mtd, loff_t start, size_t len, + size_t *retlen, const u_char *buf); + +static unsigned long my_bank_size; + +/* Listing of parts and sizes. We need this table to learn the sector + size of the chip and the total length */ +static const struct JEDECTable JEDEC_table[] = { + { + .jedec = 0x013D, + .name = "AMD Am29F017D", + .size = 2*1024*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { + .jedec = 0x01AD, + .name = "AMD Am29F016", + .size = 2*1024*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { + .jedec = 0x01D5, + .name = "AMD Am29F080", + .size = 1*1024*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { + .jedec = 0x01A4, + .name = "AMD Am29F040", + .size = 512*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { + .jedec = 0x20E3, + .name = "AMD Am29W040B", + .size = 512*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { + .jedec = 0xC2AD, + .name = "Macronix MX29F016", + .size = 2*1024*1024, + .sectorsize = 64*1024, + .capabilities = MTD_CAP_NORFLASH + }, + { .jedec = 0x0 } +}; + +static const struct JEDECTable *jedec_idtoinf(__u8 mfr,__u8 id); +static void jedec_sync(struct mtd_info *mtd) {}; +static int jedec_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf); +static int jedec_read_banked(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf); + +static struct mtd_info *jedec_probe(struct map_info *map); + + + +static struct mtd_chip_driver jedec_chipdrv = { + .probe = jedec_probe, + .name = "jedec", + .module = THIS_MODULE +}; + +/* Probe entry point */ + +static struct mtd_info *jedec_probe(struct map_info *map) +{ + struct mtd_info *MTD; + struct jedec_private *priv; + unsigned long Base; + unsigned long SectorSize; + unsigned count; + unsigned I,Uniq; + char Part[200]; + memset(&priv,0,sizeof(priv)); + + MTD = kmalloc(sizeof(struct mtd_info) + sizeof(struct jedec_private), GFP_KERNEL); + if (!MTD) + return NULL; + + memset(MTD, 0, sizeof(struct mtd_info) + sizeof(struct jedec_private)); + priv = (struct jedec_private *)&MTD[1]; + + my_bank_size = map->size; + + if (map->size/my_bank_size > MAX_JEDEC_CHIPS) + { + printk("mtd: Increase MAX_JEDEC_CHIPS, too many banks.\n"); + kfree(MTD); + return NULL; + } + + for (Base = 0; Base < map->size; Base += my_bank_size) + { + // Perhaps zero could designate all tests? + if (map->buswidth == 0) + map->buswidth = 1; + + if (map->buswidth == 1){ + if (jedec_probe8(map,Base,priv) == 0) { + printk("did recognize jedec chip\n"); + kfree(MTD); + return NULL; + } + } + if (map->buswidth == 2) + jedec_probe16(map,Base,priv); + if (map->buswidth == 4) + jedec_probe32(map,Base,priv); + } + + // Get the biggest sector size + SectorSize = 0; + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + // printk("priv->chips[%d].jedec is %x\n",I,priv->chips[I].jedec); + // printk("priv->chips[%d].sectorsize is %lx\n",I,priv->chips[I].sectorsize); + if (priv->chips[I].sectorsize > SectorSize) + SectorSize = priv->chips[I].sectorsize; + } + + // Quickly ensure that the other sector sizes are factors of the largest + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + if ((SectorSize/priv->chips[I].sectorsize)*priv->chips[I].sectorsize != SectorSize) + { + printk("mtd: Failed. Device has incompatible mixed sector sizes\n"); + kfree(MTD); + return NULL; + } + } + + /* Generate a part name that includes the number of different chips and + other configuration information */ + count = 1; + strlcpy(Part,map->name,sizeof(Part)-10); + strcat(Part," "); + Uniq = 0; + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + const struct JEDECTable *JEDEC; + + if (priv->chips[I+1].jedec == priv->chips[I].jedec) + { + count++; + continue; + } + + // Locate the chip in the jedec table + JEDEC = jedec_idtoinf(priv->chips[I].jedec >> 8,priv->chips[I].jedec); + if (JEDEC == 0) + { + printk("mtd: Internal Error, JEDEC not set\n"); + kfree(MTD); + return NULL; + } + + if (Uniq != 0) + strcat(Part,","); + Uniq++; + + if (count != 1) + sprintf(Part+strlen(Part),"%x*[%s]",count,JEDEC->name); + else + sprintf(Part+strlen(Part),"%s",JEDEC->name); + if (strlen(Part) > sizeof(Part)*2/3) + break; + count = 1; + } + + /* Determine if the chips are organized in a linear fashion, or if there + are empty banks. Note, the last bank does not count here, only the + first banks are important. Holes on non-bank boundaries can not exist + due to the way the detection algorithm works. */ + if (priv->size < my_bank_size) + my_bank_size = priv->size; + priv->is_banked = 0; + //printk("priv->size is %x, my_bank_size is %x\n",priv->size,my_bank_size); + //printk("priv->bank_fill[0] is %x\n",priv->bank_fill[0]); + if (!priv->size) { + printk("priv->size is zero\n"); + kfree(MTD); + return NULL; + } + if (priv->size/my_bank_size) { + if (priv->size/my_bank_size == 1) { + priv->size = my_bank_size; + } + else { + for (I = 0; I != priv->size/my_bank_size - 1; I++) + { + if (priv->bank_fill[I] != my_bank_size) + priv->is_banked = 1; + + /* This even could be eliminated, but new de-optimized read/write + functions have to be written */ + printk("priv->bank_fill[%d] is %lx, priv->bank_fill[0] is %lx\n",I,priv->bank_fill[I],priv->bank_fill[0]); + if (priv->bank_fill[I] != priv->bank_fill[0]) + { + printk("mtd: Failed. Cannot handle unsymmetric banking\n"); + kfree(MTD); + return NULL; + } + } + } + } + if (priv->is_banked == 1) + strcat(Part,", banked"); + + // printk("Part: '%s'\n",Part); + + memset(MTD,0,sizeof(*MTD)); + // strlcpy(MTD->name,Part,sizeof(MTD->name)); + MTD->name = map->name; + MTD->type = MTD_NORFLASH; + MTD->flags = MTD_CAP_NORFLASH; + MTD->erasesize = SectorSize*(map->buswidth); + // printk("MTD->erasesize is %x\n",(unsigned int)MTD->erasesize); + MTD->size = priv->size; + // printk("MTD->size is %x\n",(unsigned int)MTD->size); + //MTD->module = THIS_MODULE; // ? Maybe this should be the low level module? + MTD->erase = flash_erase; + if (priv->is_banked == 1) + MTD->read = jedec_read_banked; + else + MTD->read = jedec_read; + MTD->write = flash_write; + MTD->sync = jedec_sync; + MTD->priv = map; + map->fldrv_priv = priv; + map->fldrv = &jedec_chipdrv; + __module_get(THIS_MODULE); + return MTD; +} + +/* Helper for the JEDEC function, JEDEC numbers all have odd parity */ +static int checkparity(u_char C) +{ + u_char parity = 0; + while (C != 0) + { + parity ^= C & 1; + C >>= 1; + } + + return parity == 1; +} + + +/* Take an array of JEDEC numbers that represent interleved flash chips + and process them. Check to make sure they are good JEDEC numbers, look + them up and then add them to the chip list */ +static int handle_jedecs(struct map_info *map,__u8 *Mfg,__u8 *Id,unsigned Count, + unsigned long base,struct jedec_private *priv) +{ + unsigned I,J; + unsigned long Size; + unsigned long SectorSize; + const struct JEDECTable *JEDEC; + + // Test #2 JEDEC numbers exhibit odd parity + for (I = 0; I != Count; I++) + { + if (checkparity(Mfg[I]) == 0 || checkparity(Id[I]) == 0) + return 0; + } + + // Finally, just make sure all the chip sizes are the same + JEDEC = jedec_idtoinf(Mfg[0],Id[0]); + + if (JEDEC == 0) + { + printk("mtd: Found JEDEC flash chip, but do not have a table entry for %x:%x\n",Mfg[0],Mfg[1]); + return 0; + } + + Size = JEDEC->size; + SectorSize = JEDEC->sectorsize; + for (I = 0; I != Count; I++) + { + JEDEC = jedec_idtoinf(Mfg[0],Id[0]); + if (JEDEC == 0) + { + printk("mtd: Found JEDEC flash chip, but do not have a table entry for %x:%x\n",Mfg[0],Mfg[1]); + return 0; + } + + if (Size != JEDEC->size || SectorSize != JEDEC->sectorsize) + { + printk("mtd: Failed. Interleved flash does not have matching characteristics\n"); + return 0; + } + } + + // Load the Chips + for (I = 0; I != MAX_JEDEC_CHIPS; I++) + { + if (priv->chips[I].jedec == 0) + break; + } + + if (I + Count > MAX_JEDEC_CHIPS) + { + printk("mtd: Device has too many chips. Increase MAX_JEDEC_CHIPS\n"); + return 0; + } + + // Add them to the table + for (J = 0; J != Count; J++) + { + unsigned long Bank; + + JEDEC = jedec_idtoinf(Mfg[J],Id[J]); + priv->chips[I].jedec = (Mfg[J] << 8) | Id[J]; + priv->chips[I].size = JEDEC->size; + priv->chips[I].sectorsize = JEDEC->sectorsize; + priv->chips[I].base = base + J; + priv->chips[I].datashift = J*8; + priv->chips[I].capabilities = JEDEC->capabilities; + priv->chips[I].offset = priv->size + J; + + // log2 n :| + priv->chips[I].addrshift = 0; + for (Bank = Count; Bank != 1; Bank >>= 1, priv->chips[I].addrshift++); + + // Determine how filled this bank is. + Bank = base & (~(my_bank_size-1)); + if (priv->bank_fill[Bank/my_bank_size] < base + + (JEDEC->size << priv->chips[I].addrshift) - Bank) + priv->bank_fill[Bank/my_bank_size] = base + (JEDEC->size << priv->chips[I].addrshift) - Bank; + I++; + } + + priv->size += priv->chips[I-1].size*Count; + + return priv->chips[I-1].size; +} + +/* Lookup the chip information from the JEDEC ID table. */ +static const struct JEDECTable *jedec_idtoinf(__u8 mfr,__u8 id) +{ + __u16 Id = (mfr << 8) | id; + unsigned long I = 0; + for (I = 0; JEDEC_table[I].jedec != 0; I++) + if (JEDEC_table[I].jedec == Id) + return JEDEC_table + I; + return NULL; +} + +// Look for flash using an 8 bit bus interface +static int jedec_probe8(struct map_info *map,unsigned long base, + struct jedec_private *priv) +{ + #define flread(x) map_read8(map,base+x) + #define flwrite(v,x) map_write8(map,v,base+x) + + const unsigned long AutoSel1 = 0xAA; + const unsigned long AutoSel2 = 0x55; + const unsigned long AutoSel3 = 0x90; + const unsigned long Reset = 0xF0; + __u32 OldVal; + __u8 Mfg[1]; + __u8 Id[1]; + unsigned I; + unsigned long Size; + + // Wait for any write/erase operation to settle + OldVal = flread(base); + for (I = 0; OldVal != flread(base) && I < 10000; I++) + OldVal = flread(base); + + // Reset the chip + flwrite(Reset,0x555); + + // Send the sequence + flwrite(AutoSel1,0x555); + flwrite(AutoSel2,0x2AA); + flwrite(AutoSel3,0x555); + + // Get the JEDEC numbers + Mfg[0] = flread(0); + Id[0] = flread(1); + // printk("Mfg is %x, Id is %x\n",Mfg[0],Id[0]); + + Size = handle_jedecs(map,Mfg,Id,1,base,priv); + // printk("handle_jedecs Size is %x\n",(unsigned int)Size); + if (Size == 0) + { + flwrite(Reset,0x555); + return 0; + } + + + // Reset. + flwrite(Reset,0x555); + + return 1; + + #undef flread + #undef flwrite +} + +// Look for flash using a 16 bit bus interface (ie 2 8-bit chips) +static int jedec_probe16(struct map_info *map,unsigned long base, + struct jedec_private *priv) +{ + return 0; +} + +// Look for flash using a 32 bit bus interface (ie 4 8-bit chips) +static int jedec_probe32(struct map_info *map,unsigned long base, + struct jedec_private *priv) +{ + #define flread(x) map_read32(map,base+((x)<<2)) + #define flwrite(v,x) map_write32(map,v,base+((x)<<2)) + + const unsigned long AutoSel1 = 0xAAAAAAAA; + const unsigned long AutoSel2 = 0x55555555; + const unsigned long AutoSel3 = 0x90909090; + const unsigned long Reset = 0xF0F0F0F0; + __u32 OldVal; + __u8 Mfg[4]; + __u8 Id[4]; + unsigned I; + unsigned long Size; + + // Wait for any write/erase operation to settle + OldVal = flread(base); + for (I = 0; OldVal != flread(base) && I < 10000; I++) + OldVal = flread(base); + + // Reset the chip + flwrite(Reset,0x555); + + // Send the sequence + flwrite(AutoSel1,0x555); + flwrite(AutoSel2,0x2AA); + flwrite(AutoSel3,0x555); + + // Test #1, JEDEC numbers are readable from 0x??00/0x??01 + if (flread(0) != flread(0x100) || + flread(1) != flread(0x101)) + { + flwrite(Reset,0x555); + return 0; + } + + // Split up the JEDEC numbers + OldVal = flread(0); + for (I = 0; I != 4; I++) + Mfg[I] = (OldVal >> (I*8)); + OldVal = flread(1); + for (I = 0; I != 4; I++) + Id[I] = (OldVal >> (I*8)); + + Size = handle_jedecs(map,Mfg,Id,4,base,priv); + if (Size == 0) + { + flwrite(Reset,0x555); + return 0; + } + + /* Check if there is address wrap around within a single bank, if this + returns JEDEC numbers then we assume that it is wrap around. Notice + we call this routine with the JEDEC return still enabled, if two or + more flashes have a truncated address space the probe test will still + work */ + if (base + (Size<<2)+0x555 < map->size && + base + (Size<<2)+0x555 < (base & (~(my_bank_size-1))) + my_bank_size) + { + if (flread(base+Size) != flread(base+Size + 0x100) || + flread(base+Size + 1) != flread(base+Size + 0x101)) + { + jedec_probe32(map,base+Size,priv); + } + } + + // Reset. + flwrite(0xF0F0F0F0,0x555); + + return 1; + + #undef flread + #undef flwrite +} + +/* Linear read. */ +static int jedec_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) +{ + struct map_info *map = mtd->priv; + + map_copy_from(map, buf, from, len); + *retlen = len; + return 0; +} + +/* Banked read. Take special care to jump past the holes in the bank + mapping. This version assumes symetry in the holes.. */ +static int jedec_read_banked(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) +{ + struct map_info *map = mtd->priv; + struct jedec_private *priv = map->fldrv_priv; + + *retlen = 0; + while (len > 0) + { + // Determine what bank and offset into that bank the first byte is + unsigned long bank = from & (~(priv->bank_fill[0]-1)); + unsigned long offset = from & (priv->bank_fill[0]-1); + unsigned long get = len; + if (priv->bank_fill[0] - offset < len) + get = priv->bank_fill[0] - offset; + + bank /= priv->bank_fill[0]; + map_copy_from(map,buf + *retlen,bank*my_bank_size + offset,get); + + len -= get; + *retlen += get; + from += get; + } + return 0; +} + +/* Pass the flags value that the flash return before it re-entered read + mode. */ +static void jedec_flash_failed(unsigned char code) +{ + /* Bit 5 being high indicates that there was an internal device + failure, erasure time limits exceeded or something */ + if ((code & (1 << 5)) != 0) + { + printk("mtd: Internal Flash failure\n"); + return; + } + printk("mtd: Programming didn't take\n"); +} + +/* This uses the erasure function described in the AMD Flash Handbook, + it will work for flashes with a fixed sector size only. Flashes with + a selection of sector sizes (ie the AMD Am29F800B) will need a different + routine. This routine tries to parallize erasing multiple chips/sectors + where possible */ +static int flash_erase(struct mtd_info *mtd, struct erase_info *instr) +{ + // Does IO to the currently selected chip + #define flread(x) map_read8(map,chip->base+((x)<<chip->addrshift)) + #define flwrite(v,x) map_write8(map,v,chip->base+((x)<<chip->addrshift)) + + unsigned long Time = 0; + unsigned long NoTime = 0; + unsigned long start = instr->addr, len = instr->len; + unsigned int I; + struct map_info *map = mtd->priv; + struct jedec_private *priv = map->fldrv_priv; + + // Verify the arguments.. + if (start + len > mtd->size || + (start % mtd->erasesize) != 0 || + (len % mtd->erasesize) != 0 || + (len/mtd->erasesize) == 0) + return -EINVAL; + + jedec_flash_chip_scan(priv,start,len); + + // Start the erase sequence on each chip + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + unsigned long off; + struct jedec_flash_chip *chip = priv->chips + I; + + if (chip->length == 0) + continue; + + if (chip->start + chip->length > chip->size) + { + printk("DIE\n"); + return -EIO; + } + + flwrite(0xF0,chip->start + 0x555); + flwrite(0xAA,chip->start + 0x555); + flwrite(0x55,chip->start + 0x2AA); + flwrite(0x80,chip->start + 0x555); + flwrite(0xAA,chip->start + 0x555); + flwrite(0x55,chip->start + 0x2AA); + + /* Once we start selecting the erase sectors the delay between each + command must not exceed 50us or it will immediately start erasing + and ignore the other sectors */ + for (off = 0; off < len; off += chip->sectorsize) + { + // Check to make sure we didn't timeout + flwrite(0x30,chip->start + off); + if (off == 0) + continue; + if ((flread(chip->start + off) & (1 << 3)) != 0) + { + printk("mtd: Ack! We timed out the erase timer!\n"); + return -EIO; + } + } + } + + /* We could split this into a timer routine and return early, performing + background erasure.. Maybe later if the need warrents */ + + /* Poll the flash for erasure completion, specs say this can take as long + as 480 seconds to do all the sectors (for a 2 meg flash). + Erasure time is dependent on chip age, temp and wear.. */ + + /* This being a generic routine assumes a 32 bit bus. It does read32s + and bundles interleved chips into the same grouping. This will work + for all bus widths */ + Time = 0; + NoTime = 0; + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + struct jedec_flash_chip *chip = priv->chips + I; + unsigned long off = 0; + unsigned todo[4] = {0,0,0,0}; + unsigned todo_left = 0; + unsigned J; + + if (chip->length == 0) + continue; + + /* Find all chips in this data line, realistically this is all + or nothing up to the interleve count */ + for (J = 0; priv->chips[J].jedec != 0 && J < MAX_JEDEC_CHIPS; J++) + { + if ((priv->chips[J].base & (~((1<<chip->addrshift)-1))) == + (chip->base & (~((1<<chip->addrshift)-1)))) + { + todo_left++; + todo[priv->chips[J].base & ((1<<chip->addrshift)-1)] = 1; + } + } + + /* printk("todo: %x %x %x %x\n",(short)todo[0],(short)todo[1], + (short)todo[2],(short)todo[3]); + */ + while (1) + { + __u32 Last[4]; + unsigned long Count = 0; + + /* During erase bit 7 is held low and bit 6 toggles, we watch this, + should it stop toggling or go high then the erase is completed, + or this is not really flash ;> */ + switch (map->buswidth) { + case 1: + Last[0] = map_read8(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[1] = map_read8(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[2] = map_read8(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + case 2: + Last[0] = map_read16(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[1] = map_read16(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[2] = map_read16(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + case 3: + Last[0] = map_read32(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[1] = map_read32(map,(chip->base >> chip->addrshift) + chip->start + off); + Last[2] = map_read32(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + } + Count = 3; + while (todo_left != 0) + { + for (J = 0; J != 4; J++) + { + __u8 Byte1 = (Last[(Count-1)%4] >> (J*8)) & 0xFF; + __u8 Byte2 = (Last[(Count-2)%4] >> (J*8)) & 0xFF; + __u8 Byte3 = (Last[(Count-3)%4] >> (J*8)) & 0xFF; + if (todo[J] == 0) + continue; + + if ((Byte1 & (1 << 7)) == 0 && Byte1 != Byte2) + { +// printk("Check %x %x %x\n",(short)J,(short)Byte1,(short)Byte2); + continue; + } + + if (Byte1 == Byte2) + { + jedec_flash_failed(Byte3); + return -EIO; + } + + todo[J] = 0; + todo_left--; + } + +/* if (NoTime == 0) + Time += HZ/10 - schedule_timeout(HZ/10);*/ + NoTime = 0; + + switch (map->buswidth) { + case 1: + Last[Count % 4] = map_read8(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + case 2: + Last[Count % 4] = map_read16(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + case 4: + Last[Count % 4] = map_read32(map,(chip->base >> chip->addrshift) + chip->start + off); + break; + } + Count++; + +/* // Count time, max of 15s per sector (according to AMD) + if (Time > 15*len/mtd->erasesize*HZ) + { + printk("mtd: Flash Erase Timed out\n"); + return -EIO; + } */ + } + + // Skip to the next chip if we used chip erase + if (chip->length == chip->size) + off = chip->size; + else + off += chip->sectorsize; + + if (off >= chip->length) + break; + NoTime = 1; + } + + for (J = 0; priv->chips[J].jedec != 0 && J < MAX_JEDEC_CHIPS; J++) + { + if ((priv->chips[J].base & (~((1<<chip->addrshift)-1))) == + (chip->base & (~((1<<chip->addrshift)-1)))) + priv->chips[J].length = 0; + } + } + + //printk("done\n"); + instr->state = MTD_ERASE_DONE; + mtd_erase_callback(instr); + return 0; + + #undef flread + #undef flwrite +} + +/* This is the simple flash writing function. It writes to every byte, in + sequence. It takes care of how to properly address the flash if + the flash is interleved. It can only be used if all the chips in the + array are identical!*/ +static int flash_write(struct mtd_info *mtd, loff_t start, size_t len, + size_t *retlen, const u_char *buf) +{ + /* Does IO to the currently selected chip. It takes the bank addressing + base (which is divisible by the chip size) adds the necessary lower bits + of addrshift (interleave index) and then adds the control register index. */ + #define flread(x) map_read8(map,base+(off&((1<<chip->addrshift)-1))+((x)<<chip->addrshift)) + #define flwrite(v,x) map_write8(map,v,base+(off&((1<<chip->addrshift)-1))+((x)<<chip->addrshift)) + + struct map_info *map = mtd->priv; + struct jedec_private *priv = map->fldrv_priv; + unsigned long base; + unsigned long off; + size_t save_len = len; + + if (start + len > mtd->size) + return -EIO; + + //printk("Here"); + + //printk("flash_write: start is %x, len is %x\n",start,(unsigned long)len); + while (len != 0) + { + struct jedec_flash_chip *chip = priv->chips; + unsigned long bank; + unsigned long boffset; + + // Compute the base of the flash. + off = ((unsigned long)start) % (chip->size << chip->addrshift); + base = start - off; + + // Perform banked addressing translation. + bank = base & (~(priv->bank_fill[0]-1)); + boffset = base & (priv->bank_fill[0]-1); + bank = (bank/priv->bank_fill[0])*my_bank_size; + base = bank + boffset; + + // printk("Flasing %X %X %X\n",base,chip->size,len); + // printk("off is %x, compare with %x\n",off,chip->size << chip->addrshift); + + // Loop over this page + for (; off != (chip->size << chip->addrshift) && len != 0; start++, len--, off++,buf++) + { + unsigned char oldbyte = map_read8(map,base+off); + unsigned char Last[4]; + unsigned long Count = 0; + + if (oldbyte == *buf) { + // printk("oldbyte and *buf is %x,len is %x\n",oldbyte,len); + continue; + } + if (((~oldbyte) & *buf) != 0) + printk("mtd: warn: Trying to set a 0 to a 1\n"); + + // Write + flwrite(0xAA,0x555); + flwrite(0x55,0x2AA); + flwrite(0xA0,0x555); + map_write8(map,*buf,base + off); + Last[0] = map_read8(map,base + off); + Last[1] = map_read8(map,base + off); + Last[2] = map_read8(map,base + off); + + /* Wait for the flash to finish the operation. We store the last 4 + status bytes that have been retrieved so we can determine why + it failed. The toggle bits keep toggling when there is a + failure */ + for (Count = 3; Last[(Count - 1) % 4] != Last[(Count - 2) % 4] && + Count < 10000; Count++) + Last[Count % 4] = map_read8(map,base + off); + if (Last[(Count - 1) % 4] != *buf) + { + jedec_flash_failed(Last[(Count - 3) % 4]); + return -EIO; + } + } + } + *retlen = save_len; + return 0; +} + +/* This is used to enhance the speed of the erase routine, + when things are being done to multiple chips it is possible to + parallize the operations, particularly full memory erases of multi + chip memories benifit */ +static void jedec_flash_chip_scan(struct jedec_private *priv,unsigned long start, + unsigned long len) +{ + unsigned int I; + + // Zero the records + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + priv->chips[I].start = priv->chips[I].length = 0; + + // Intersect the region with each chip + for (I = 0; priv->chips[I].jedec != 0 && I < MAX_JEDEC_CHIPS; I++) + { + struct jedec_flash_chip *chip = priv->chips + I; + unsigned long ByteStart; + unsigned long ChipEndByte = chip->offset + (chip->size << chip->addrshift); + + // End is before this chip or the start is after it + if (start+len < chip->offset || + ChipEndByte - (1 << chip->addrshift) < start) + continue; + + if (start < chip->offset) + { + ByteStart = chip->offset; + chip->start = 0; + } + else + { + chip->start = (start - chip->offset + (1 << chip->addrshift)-1) >> chip->addrshift; + ByteStart = start; + } + + if (start + len >= ChipEndByte) + chip->length = (ChipEndByte - ByteStart) >> chip->addrshift; + else + chip->length = (start + len - ByteStart + (1 << chip->addrshift)-1) >> chip->addrshift; + } +} + +int __init jedec_init(void) +{ + register_mtd_chip_driver(&jedec_chipdrv); + return 0; +} + +static void __exit jedec_exit(void) +{ + unregister_mtd_chip_driver(&jedec_chipdrv); +} + +module_init(jedec_init); +module_exit(jedec_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jason Gunthorpe <jgg@deltatee.com> et al."); +MODULE_DESCRIPTION("Old MTD chip driver for JEDEC-compliant flash chips"); |