diff options
Diffstat (limited to 'arch/cris/arch-v10/drivers/axisflashmap.c')
| -rw-r--r-- | arch/cris/arch-v10/drivers/axisflashmap.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/drivers/axisflashmap.c b/arch/cris/arch-v10/drivers/axisflashmap.c new file mode 100644 index 00000000000..fb7d4855ea6 --- /dev/null +++ b/arch/cris/arch-v10/drivers/axisflashmap.c @@ -0,0 +1,541 @@ +/* + * 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 1.10 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 <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/config.h> +#include <linux/init.h> + +#include <linux/mtd/concat.h> +#include <linux/mtd/map.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/mtdram.h> +#include <linux/mtd/partitions.h> + +#include <asm/axisflashmap.h> +#include <asm/mmu.h> +#include <asm/arch/sv_addr_ag.h> + +#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 __u16 +#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, + sizeof(mtds) / sizeof(mtds[0]), + "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 = (struct mtd_info *)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); |