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Diffstat (limited to 'drivers/mtd/maps/microdev-flash.c')
| -rw-r--r-- | drivers/mtd/maps/microdev-flash.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/mtd/maps/microdev-flash.c b/drivers/mtd/maps/microdev-flash.c new file mode 100644 index 00000000000000..a38b9daac1b467 --- /dev/null +++ b/drivers/mtd/maps/microdev-flash.c @@ -0,0 +1,165 @@ +/* + * drivers/mtd/maps/microdev-flash.c + * + * Flash Mapping for the SuperH SH4-202 MicroDev. + * + * Copyright (C) 2004 SuperH, Inc. + * Copyright (C) 2004 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/map.h> +#include <linux/mtd/partitions.h> +#include <asm/io.h> + +/* + * The SH4-202 MicroDev has 32M of Intel StrataFlash mapped into the + * beginning of the FEMI address space (mapped to P0). MicroDev flash + * consists of 2x16M chips, mapped contiguously, and accessed with a + * 32-bit buswidth. + * + * Additionally, the MicroDev also supports booting from an EEPROM. + * In the event that the EEPROM is configured, it is mapped in the + * same address space window as the StrataFlash. As such, we can only + * use one at a time. + * + * Since the EEPROM is only accessible with an 8-bit buswidth, flash + * is preferrable as far as performance is concerned. + */ +struct map_info microdev_flash_map = { + .name = "MicroDev Flash", + .size = 0x02000000, + .bankwidth = 4, +}; + +struct map_info microdev_eeprom_map = { + .name = "MicroDev EEPROM", + .size = 0x00100000, + .bankwidth = 1, +}; + +static const char *probes[] = { "RedBoot", "cmdlinepart", NULL }; +static struct mtd_partition *parsed_parts; + +/* + * Default partition map. + */ +static struct mtd_partition microdev_partitions[] = { +#ifdef CONFIG_MTD_PARTITIONS + { + .name = "bootloader", + .size = 0x00080000, + .mask_flags = MTD_WRITEABLE, /* force read-only */ + }, { + .name = "User FS", + .offset = MTDPART_OFS_APPEND, + .size = MTDPART_SIZ_FULL, + }, +#endif +}; + +static struct mtd_info *microdev_flash; +static struct mtd_info *microdev_eeprom; +static struct mtd_info *microdev_mtd; + +static void show_map_info(struct map_info *info) +{ + unsigned long addr; + + if (!info) + return; + + addr = info->phys & 0x1fffffff; + + printk(KERN_NOTICE "%s at 0x%08lx:0x%08lx, using a %d-bit bankwidth.\n", + info->name, addr, addr + info->size, info->bankwidth << 3); +} + +static int __init microdev_map_init(void) +{ + struct mtd_partition *parts; + int nr_parts, parsed_nr_parts; + + /* Flash mapped at FEMI area 0 */ + microdev_flash_map.phys = 0; + microdev_flash_map.virt = (void __iomem *)P2SEGADDR(0); + + /* EEPROM mapped in the same place */ + microdev_eeprom_map.phys = 0; + microdev_eeprom_map.virt = (void __iomem *)P2SEGADDR(0); + + simple_map_init(µdev_flash_map); + simple_map_init(µdev_eeprom_map); + + /* Try the flash first */ + printk(KERN_NOTICE "MicroDev flash: probing for flash chips at 0x00000000:\n"); + microdev_flash = do_map_probe("cfi_probe", µdev_flash_map); + if (!microdev_flash) { + printk(KERN_NOTICE "Flash chips not detected, probing for EEPROM\n"); + + /* No luck, try EEPROM */ + microdev_eeprom = do_map_probe("map_rom", µdev_eeprom_map); + if (!microdev_eeprom) { + /* Nope.. */ + printk(KERN_ERR "nothing found\n"); + return -ENXIO; + } + } + + if (microdev_flash) { + microdev_mtd = microdev_flash; + show_map_info(µdev_flash_map); + } else { + microdev_mtd = microdev_eeprom; + show_map_info(µdev_eeprom_map); + } + + microdev_mtd->owner = THIS_MODULE; + + /* Start out with a static map.. */ + parts = microdev_partitions; + nr_parts = ARRAY_SIZE(microdev_partitions); + +#ifdef CONFIG_MTD_PARTITIONS + /* Try to parse the partitions */ + parsed_nr_parts = parse_mtd_partitions(microdev_mtd, probes, &parsed_parts, 0); + if (parsed_nr_parts > 0) { + parts = parsed_parts; + nr_parts = parsed_nr_parts; + } +#endif + + if (nr_parts > 0) { + add_mtd_partitions(microdev_mtd, parts, nr_parts); + } else { + add_mtd_device(microdev_mtd); + } + + return 0; +} + +static void __exit microdev_map_exit(void) +{ + if (parsed_parts) { + del_mtd_partitions(microdev_mtd); + } else { + del_mtd_device(microdev_mtd); + } + + map_destroy(microdev_mtd); +} + +module_init(microdev_map_init); +module_exit(microdev_map_exit); + +MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>"); +MODULE_DESCRIPTION("MTD map driver for SuperH SH4-202 MicroDev"); +MODULE_LICENSE("GPL"); + |