/* * $Id: ixp4xx.c,v 1.13 2005/11/16 16:23:21 dvrabel Exp $ * * drivers/mtd/maps/ixp4xx.c * * MTD Map file for IXP4XX based systems. Please do not make per-board * changes in here. If your board needs special setup, do it in your * platform level code in arch/arm/mach-ixp4xx/board-setup.c * * Original Author: Intel Corporation * Maintainer: Deepak Saxena <dsaxena@mvista.com> * * Copyright (C) 2002 Intel Corporation * Copyright (C) 2003-2004 MontaVista Software, Inc. * */ #include <linux/module.h> #include <linux/types.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/slab.h> #include <linux/ioport.h> #include <linux/device.h> #include <linux/platform_device.h> #include <linux/mtd/mtd.h> #include <linux/mtd/map.h> #include <linux/mtd/partitions.h> #include <asm/io.h> #include <asm/mach/flash.h> #include <linux/reboot.h> /* * Read/write a 16 bit word from flash address 'addr'. * * When the cpu is in little-endian mode it swizzles the address lines * ('address coherency') so we need to undo the swizzling to ensure commands * and the like end up on the correct flash address. * * To further complicate matters, due to the way the expansion bus controller * handles 32 bit reads, the byte stream ABCD is stored on the flash as: * D15 D0 * +---+---+ * | A | B | 0 * +---+---+ * | C | D | 2 * +---+---+ * This means that on LE systems each 16 bit word must be swapped. Note that * this requires CONFIG_MTD_CFI_BE_BYTE_SWAP to be enabled to 'unswap' the CFI * data and other flash commands which are always in D7-D0. */ #ifndef __ARMEB__ #ifndef CONFIG_MTD_CFI_BE_BYTE_SWAP # error CONFIG_MTD_CFI_BE_BYTE_SWAP required #endif static inline u16 flash_read16(void __iomem *addr) { return be16_to_cpu(__raw_readw((void __iomem *)((unsigned long)addr ^ 0x2))); } static inline void flash_write16(u16 d, void __iomem *addr) { __raw_writew(cpu_to_be16(d), (void __iomem *)((unsigned long)addr ^ 0x2)); } #define BYTE0(h) ((h) & 0xFF) #define BYTE1(h) (((h) >> 8) & 0xFF) #else static inline u16 flash_read16(const void __iomem *addr) { return __raw_readw(addr); } static inline void flash_write16(u16 d, void __iomem *addr) { __raw_writew(d, addr); } #define BYTE0(h) (((h) >> 8) & 0xFF) #define BYTE1(h) ((h) & 0xFF) #endif static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs) { map_word val; val.x[0] = flash_read16(map->virt + ofs); return val; } /* * The IXP4xx expansion bus only allows 16-bit wide acceses * when attached to a 16-bit wide device (such as the 28F128J3A), * so we can't just memcpy_fromio(). */ static void ixp4xx_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len) { u8 *dest = (u8 *) to; void __iomem *src = map->virt + from; if (len <= 0) return; if (from & 1) { *dest++ = BYTE1(flash_read16(src)); src++; --len; } while (len >= 2) { u16 data = flash_read16(src); *dest++ = BYTE0(data); *dest++ = BYTE1(data); src += 2; len -= 2; } if (len > 0) *dest++ = BYTE0(flash_read16(src)); } /* * Unaligned writes are ignored, causing the 8-bit * probe to fail and proceed to the 16-bit probe (which succeeds). */ static void ixp4xx_probe_write16(struct map_info *map, map_word d, unsigned long adr) { if (!(adr & 1)) flash_write16(d.x[0], map->virt + adr); } /* * Fast write16 function without the probing check above */ static void ixp4xx_write16(struct map_info *map, map_word d, unsigned long adr) { flash_write16(d.x[0], map->virt + adr); } struct ixp4xx_flash_info { struct mtd_info *mtd; struct map_info map; struct mtd_partition *partitions; struct resource *res; }; static const char *probes[] = { "RedBoot", "cmdlinepart", NULL }; static int ixp4xx_flash_remove(struct platform_device *dev) { struct flash_platform_data *plat = dev->dev.platform_data; struct ixp4xx_flash_info *info = platform_get_drvdata(dev); platform_set_drvdata(dev, NULL); if(!info) return 0; if (info->mtd) { del_mtd_partitions(info->mtd); map_destroy(info->mtd); } if (info->map.virt) iounmap(info->map.virt); kfree(info->partitions); if (info->res) { release_resource(info->res); kfree(info->res); } if (plat->exit) plat->exit(); return 0; } static int ixp4xx_flash_probe(struct platform_device *dev) { struct flash_platform_data *plat = dev->dev.platform_data; struct ixp4xx_flash_info *info; int err = -1; if (!plat) return -ENODEV; if (plat->init) { err = plat->init(); if (err) return err; } info = kmalloc(sizeof(struct ixp4xx_flash_info), GFP_KERNEL); if(!info) { err = -ENOMEM; goto Error; } memzero(info, sizeof(struct ixp4xx_flash_info)); platform_set_drvdata(dev, info); /* * Tell the MTD layer we're not 1:1 mapped so that it does * not attempt to do a direct access on us. */ info->map.phys = NO_XIP; info->map.size = dev->resource->end - dev->resource->start + 1; /* * We only support 16-bit accesses for now. If and when * any board use 8-bit access, we'll fixup the driver to * handle that. */ info->map.bankwidth = 2; info->map.name = dev->dev.bus_id; info->map.read = ixp4xx_read16, info->map.write = ixp4xx_probe_write16, info->map.copy_from = ixp4xx_copy_from, info->res = request_mem_region(dev->resource->start, dev->resource->end - dev->resource->start + 1, "IXP4XXFlash"); if (!info->res) { printk(KERN_ERR "IXP4XXFlash: Could not reserve memory region\n"); err = -ENOMEM; goto Error; } info->map.virt = ioremap(dev->resource->start, dev->resource->end - dev->resource->start + 1); if (!info->map.virt) { printk(KERN_ERR "IXP4XXFlash: Failed to ioremap region\n"); err = -EIO; goto Error; } info->mtd = do_map_probe(plat->map_name, &info->map); if (!info->mtd) { printk(KERN_ERR "IXP4XXFlash: map_probe failed\n"); err = -ENXIO; goto Error; } info->mtd->owner = THIS_MODULE; /* Use the fast version */ info->map.write = ixp4xx_write16, err = parse_mtd_partitions(info->mtd, probes, &info->partitions, dev->resource->start); if (err > 0) { err = add_mtd_partitions(info->mtd, info->partitions, err); if(err) printk(KERN_ERR "Could not parse partitions\n"); } if (err) goto Error; return 0; Error: ixp4xx_flash_remove(dev); return err; } static struct platform_driver ixp4xx_flash_driver = { .probe = ixp4xx_flash_probe, .remove = ixp4xx_flash_remove, .driver = { .name = "IXP4XX-Flash", }, }; static int __init ixp4xx_flash_init(void) { return platform_driver_register(&ixp4xx_flash_driver); } static void __exit ixp4xx_flash_exit(void) { platform_driver_unregister(&ixp4xx_flash_driver); } module_init(ixp4xx_flash_init); module_exit(ixp4xx_flash_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems"); MODULE_AUTHOR("Deepak Saxena");