/* * Physical mapping layer for MTD using the Axis partitiontable format * * Copyright (c) 2001, 2002 Axis Communications AB * * This file is under the GPL. * * First partition is always sector 0 regardless of if we find a partitiontable * or not. In the start of the next sector, there can be a partitiontable that * tells us what other partitions to define. If there isn't, we use a default * partition split defined below. * * $Log: axisflashmap.c,v $ * Revision 1.11 2004/11/15 10:27:14 starvik * Corrected typo (Thanks to Milton Miller ). * * Revision 1.10 2004/08/16 12:37:22 starvik * Merge of Linux 2.6.8 * * Revision 1.8 2004/05/14 07:58:03 starvik * Merge of changes from 2.4 * * Revision 1.6 2003/07/04 08:27:37 starvik * Merge of Linux 2.5.74 * * Revision 1.5 2002/12/11 13:13:57 starvik * Added arch/ to v10 specific includes * Added fix from Linux 2.4 in serial.c (flush_to_flip_buffer) * * Revision 1.4 2002/11/20 11:56:10 starvik * Merge of Linux 2.5.48 * * Revision 1.3 2002/11/13 14:54:13 starvik * Copied from linux 2.4 * * Revision 1.28 2002/10/01 08:08:43 jonashg * The first partition ends at the start of the partition table. * * Revision 1.27 2002/08/21 09:23:13 jonashg * Speling. * * Revision 1.26 2002/08/21 08:35:20 jonashg * Cosmetic change to printouts. * * Revision 1.25 2002/08/21 08:15:42 jonashg * Made it compile even without CONFIG_MTD_CONCAT defined. * * Revision 1.24 2002/08/20 13:12:35 jonashg * * New approach to probing. Probe cse0 and cse1 separately and (mtd)concat * the results. * * Removed compile time tests concerning how the mtdram driver has been * configured. The user will know about the misconfiguration at runtime * instead. (The old approach made it impossible to use mtdram for anything * else than RAM boot). * * Revision 1.23 2002/05/13 12:12:28 johana * Allow compile without CONFIG_MTD_MTDRAM but warn at compiletime and * be informative at runtime. * * Revision 1.22 2002/05/13 10:24:44 johana * Added #if checks on MTDRAM CONFIG * * Revision 1.21 2002/05/06 16:05:20 johana * Removed debug printout. * * Revision 1.20 2002/05/06 16:03:00 johana * No more cramfs as root hack in generic code. * It's handled by axisflashmap using mtdram. * * Revision 1.19 2002/03/15 17:10:28 bjornw * Changed comment about cached access since we changed this before * * Revision 1.18 2002/03/05 17:06:15 jonashg * Try amd_flash probe before cfi_probe since amd_flash driver can handle two * (or more) flash chips of different model and the cfi driver cannot. * * Revision 1.17 2001/11/12 19:42:38 pkj * Fixed compiler warnings. * * Revision 1.16 2001/11/08 11:18:58 jonashg * Always read from uncached address to avoid problems with flushing * cachelines after write and MTD-erase. No performance loss have been * seen yet. * * Revision 1.15 2001/10/19 12:41:04 jonashg * Name of probe has changed in MTD. * * Revision 1.14 2001/09/21 07:14:10 jonashg * Made root filesystem (cramfs) use mtdblock driver when booting from flash. * * Revision 1.13 2001/08/15 13:57:35 jonashg * Entire MTD updated to the linux 2.4.7 version. * * Revision 1.12 2001/06/11 09:50:30 jonashg * Oops, 2MB is 0x200000 bytes. * * Revision 1.11 2001/06/08 11:39:44 jonashg * Changed sizes and offsets in axis_default_partitions to use * CONFIG_ETRAX_PTABLE_SECTOR. * * Revision 1.10 2001/05/29 09:42:03 jonashg * Use macro for end marker length instead of sizeof. * * Revision 1.9 2001/05/29 08:52:52 jonashg * Gave names to the magic fours (size of the ptable end marker). * * Revision 1.8 2001/05/28 15:36:20 jonashg * * Removed old comment about ptable location in flash (it's a CONFIG_ option). * * Variable ptable was initialized twice to the same value. * * Revision 1.7 2001/04/05 13:41:46 markusl * Updated according to review remarks * * Revision 1.6 2001/03/07 09:21:21 bjornw * No need to waste .data * * Revision 1.5 2001/03/06 16:27:01 jonashg * Probe the entire flash area for flash devices. * * Revision 1.4 2001/02/23 12:47:15 bjornw * Uncached flash in LOW_MAP moved from 0xe to 0x8 * * Revision 1.3 2001/02/16 12:11:45 jonashg * MTD driver amd_flash is now included in MTD CVS repository. * (It's now in drivers/mtd). * * Revision 1.2 2001/02/09 11:12:22 jonashg * Support for AMD compatible non-CFI flash chips. * Only tested with Toshiba TC58FVT160 so far. * * Revision 1.1 2001/01/12 17:01:18 bjornw * * Added axisflashmap.c, a physical mapping for MTD that reads and understands * Axis partition-table format. * * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_CRIS_LOW_MAP #define FLASH_UNCACHED_ADDR KSEG_8 #define FLASH_CACHED_ADDR KSEG_5 #else #define FLASH_UNCACHED_ADDR KSEG_E #define FLASH_CACHED_ADDR KSEG_F #endif #if CONFIG_ETRAX_FLASH_BUSWIDTH==1 #define flash_data __u8 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==2 #define flash_data __u16 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==4 #define flash_data __u32 #endif /* From head.S */ extern unsigned long romfs_start, romfs_length, romfs_in_flash; /* The master mtd for the entire flash. */ struct mtd_info* axisflash_mtd = NULL; /* Map driver functions. */ static map_word flash_read(struct map_info *map, unsigned long ofs) { map_word tmp; tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs); return tmp; } static void flash_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len) { memcpy(to, (void *)(map->map_priv_1 + from), len); } static void flash_write(struct map_info *map, map_word d, unsigned long adr) { *(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0]; } /* * The map for chip select e0. * * We run into tricky coherence situations if we mix cached with uncached * accesses to we only use the uncached version here. * * The size field is the total size where the flash chips may be mapped on the * chip select. MTD probes should find all devices there and it does not matter * if there are unmapped gaps or aliases (mirrors of flash devices). The MTD * probes will ignore them. * * The start address in map_priv_1 is in virtual memory so we cannot use * MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start * address of cse0. */ static struct map_info map_cse0 = { .name = "cse0", .size = MEM_CSE0_SIZE, .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH, .read = flash_read, .copy_from = flash_copy_from, .write = flash_write, .map_priv_1 = FLASH_UNCACHED_ADDR }; /* * The map for chip select e1. * * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong * address, but there isn't. */ static struct map_info map_cse1 = { .name = "cse1", .size = MEM_CSE1_SIZE, .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH, .read = flash_read, .copy_from = flash_copy_from, .write = flash_write, .map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE }; /* If no partition-table was found, we use this default-set. */ #define MAX_PARTITIONS 7 #define NUM_DEFAULT_PARTITIONS 3 /* * Default flash size is 2MB. CONFIG_ETRAX_PTABLE_SECTOR is most likely the * size of one flash block and "filesystem"-partition needs 5 blocks to be able * to use JFFS. */ static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = { { .name = "boot firmware", .size = CONFIG_ETRAX_PTABLE_SECTOR, .offset = 0 }, { .name = "kernel", .size = 0x200000 - (6 * CONFIG_ETRAX_PTABLE_SECTOR), .offset = CONFIG_ETRAX_PTABLE_SECTOR }, { .name = "filesystem", .size = 5 * CONFIG_ETRAX_PTABLE_SECTOR, .offset = 0x200000 - (5 * CONFIG_ETRAX_PTABLE_SECTOR) } }; /* Initialize the ones normally used. */ static struct mtd_partition axis_partitions[MAX_PARTITIONS] = { { .name = "part0", .size = CONFIG_ETRAX_PTABLE_SECTOR, .offset = 0 }, { .name = "part1", .size = 0, .offset = 0 }, { .name = "part2", .size = 0, .offset = 0 }, { .name = "part3", .size = 0, .offset = 0 }, { .name = "part4", .size = 0, .offset = 0 }, { .name = "part5", .size = 0, .offset = 0 }, { .name = "part6", .size = 0, .offset = 0 }, }; /* * Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash * chips in that order (because the amd_flash-driver is faster). */ static struct mtd_info *probe_cs(struct map_info *map_cs) { struct mtd_info *mtd_cs = NULL; printk(KERN_INFO "%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n", map_cs->name, map_cs->size, map_cs->map_priv_1); #ifdef CONFIG_MTD_AMDSTD mtd_cs = do_map_probe("amd_flash", map_cs); #endif #ifdef CONFIG_MTD_CFI if (!mtd_cs) { mtd_cs = do_map_probe("cfi_probe", map_cs); } #endif return mtd_cs; } /* * Probe each chip select individually for flash chips. If there are chips on * both cse0 and cse1, the mtd_info structs will be concatenated to one struct * so that MTD partitions can cross chip boundries. * * The only known restriction to how you can mount your chips is that each * chip select must hold similar flash chips. But you need external hardware * to do that anyway and you can put totally different chips on cse0 and cse1 * so it isn't really much of a restriction. */ static struct mtd_info *flash_probe(void) { struct mtd_info *mtd_cse0; struct mtd_info *mtd_cse1; struct mtd_info *mtd_cse; mtd_cse0 = probe_cs(&map_cse0); mtd_cse1 = probe_cs(&map_cse1); if (!mtd_cse0 && !mtd_cse1) { /* No chip found. */ return NULL; } if (mtd_cse0 && mtd_cse1) { #ifdef CONFIG_MTD_CONCAT struct mtd_info *mtds[] = { mtd_cse0, mtd_cse1 }; /* Since the concatenation layer adds a small overhead we * could try to figure out if the chips in cse0 and cse1 are * identical and reprobe the whole cse0+cse1 window. But since * flash chips are slow, the overhead is relatively small. * So we use the MTD concatenation layer instead of further * complicating the probing procedure. */ mtd_cse = mtd_concat_create(mtds, ARRAY_SIZE(mtds), "cse0+cse1"); #else printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel " "(mis)configuration!\n", map_cse0.name, map_cse1.name); mtd_cse = NULL; #endif if (!mtd_cse) { printk(KERN_ERR "%s and %s: Concatenation failed!\n", map_cse0.name, map_cse1.name); /* The best we can do now is to only use what we found * at cse0. */ mtd_cse = mtd_cse0; map_destroy(mtd_cse1); } } else { mtd_cse = mtd_cse0? mtd_cse0 : mtd_cse1; } return mtd_cse; } /* * Probe the flash chip(s) and, if it succeeds, read the partition-table * and register the partitions with MTD. */ static int __init init_axis_flash(void) { struct mtd_info *mymtd; int err = 0; int pidx = 0; struct partitiontable_head *ptable_head = NULL; struct partitiontable_entry *ptable; int use_default_ptable = 1; /* Until proven otherwise. */ const char *pmsg = " /dev/flash%d at 0x%08x, size 0x%08x\n"; if (!(mymtd = flash_probe())) { /* There's no reason to use this module if no flash chip can * be identified. Make sure that's understood. */ printk(KERN_INFO "axisflashmap: Found no flash chip.\n"); } else { printk(KERN_INFO "%s: 0x%08x bytes of flash memory.\n", mymtd->name, mymtd->size); axisflash_mtd = mymtd; } if (mymtd) { mymtd->owner = THIS_MODULE; ptable_head = (struct partitiontable_head *)(FLASH_CACHED_ADDR + CONFIG_ETRAX_PTABLE_SECTOR + PARTITION_TABLE_OFFSET); } pidx++; /* First partition is always set to the default. */ if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC) && (ptable_head->size < (MAX_PARTITIONS * sizeof(struct partitiontable_entry) + PARTITIONTABLE_END_MARKER_SIZE)) && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) + ptable_head->size - PARTITIONTABLE_END_MARKER_SIZE) == PARTITIONTABLE_END_MARKER)) { /* Looks like a start, sane length and end of a * partition table, lets check csum etc. */ int ptable_ok = 0; struct partitiontable_entry *max_addr = (struct partitiontable_entry *) ((unsigned long)ptable_head + sizeof(*ptable_head) + ptable_head->size); unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR; unsigned char *p; unsigned long csum = 0; ptable = (struct partitiontable_entry *) ((unsigned long)ptable_head + sizeof(*ptable_head)); /* Lets be PARANOID, and check the checksum. */ p = (unsigned char*) ptable; while (p <= (unsigned char*)max_addr) { csum += *p++; csum += *p++; csum += *p++; csum += *p++; } ptable_ok = (csum == ptable_head->checksum); /* Read the entries and use/show the info. */ printk(KERN_INFO " Found a%s partition table at 0x%p-0x%p.\n", (ptable_ok ? " valid" : "n invalid"), ptable_head, max_addr); /* We have found a working bootblock. Now read the * partition table. Scan the table. It ends when * there is 0xffffffff, that is, empty flash. */ while (ptable_ok && ptable->offset != 0xffffffff && ptable < max_addr && pidx < MAX_PARTITIONS) { axis_partitions[pidx].offset = offset + ptable->offset; axis_partitions[pidx].size = ptable->size; printk(pmsg, pidx, axis_partitions[pidx].offset, axis_partitions[pidx].size); pidx++; ptable++; } use_default_ptable = !ptable_ok; } if (romfs_in_flash) { /* Add an overlapping device for the root partition (romfs). */ axis_partitions[pidx].name = "romfs"; axis_partitions[pidx].size = romfs_length; axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR; axis_partitions[pidx].mask_flags |= MTD_WRITEABLE; printk(KERN_INFO " Adding readonly flash partition for romfs image:\n"); printk(pmsg, pidx, axis_partitions[pidx].offset, axis_partitions[pidx].size); pidx++; } if (mymtd) { if (use_default_ptable) { printk(KERN_INFO " Using default partition table.\n"); err = add_mtd_partitions(mymtd, axis_default_partitions, NUM_DEFAULT_PARTITIONS); } else { err = add_mtd_partitions(mymtd, axis_partitions, pidx); } if (err) { panic("axisflashmap could not add MTD partitions!\n"); } } if (!romfs_in_flash) { /* Create an RAM device for the root partition (romfs). */ #if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0) /* No use trying to boot this kernel from RAM. Panic! */ printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM " "device due to kernel (mis)configuration!\n"); panic("This kernel cannot boot from RAM!\n"); #else struct mtd_info *mtd_ram; mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL); if (!mtd_ram) { panic("axisflashmap couldn't allocate memory for " "mtd_info!\n"); } printk(KERN_INFO " Adding RAM partition for romfs image:\n"); printk(pmsg, pidx, romfs_start, romfs_length); err = mtdram_init_device(mtd_ram, (void*)romfs_start, romfs_length, "romfs"); if (err) { panic("axisflashmap could not initialize MTD RAM " "device!\n"); } #endif } return err; } /* This adds the above to the kernels init-call chain. */ module_init(init_axis_flash); EXPORT_SYMBOL(axisflash_mtd);