|  | /* | 
|  | * Flash mappings described by the OF (or flattened) device tree | 
|  | * | 
|  | * Copyright (C) 2006 MontaVista Software Inc. | 
|  | * Author: Vitaly Wool <vwool@ru.mvista.com> | 
|  | * | 
|  | * Revised to handle newer style flash binding by: | 
|  | *   Copyright (C) 2007 David Gibson, IBM Corporation. | 
|  | * | 
|  | * This program is free software; you can redistribute  it and/or modify it | 
|  | * under  the terms of  the GNU General  Public License as published by the | 
|  | * Free Software Foundation;  either version 2 of the  License, or (at your | 
|  | * option) any later version. | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/device.h> | 
|  | #include <linux/mtd/mtd.h> | 
|  | #include <linux/mtd/map.h> | 
|  | #include <linux/mtd/partitions.h> | 
|  | #include <linux/of.h> | 
|  | #include <linux/of_platform.h> | 
|  |  | 
|  | struct of_flash { | 
|  | struct mtd_info		*mtd; | 
|  | struct map_info		map; | 
|  | struct resource		*res; | 
|  | #ifdef CONFIG_MTD_PARTITIONS | 
|  | struct mtd_partition	*parts; | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | #ifdef CONFIG_MTD_PARTITIONS | 
|  | #define OF_FLASH_PARTS(info)	((info)->parts) | 
|  |  | 
|  | static int parse_obsolete_partitions(struct of_device *dev, | 
|  | struct of_flash *info, | 
|  | struct device_node *dp) | 
|  | { | 
|  | int i, plen, nr_parts; | 
|  | const struct { | 
|  | u32 offset, len; | 
|  | } *part; | 
|  | const char *names; | 
|  |  | 
|  | part = of_get_property(dp, "partitions", &plen); | 
|  | if (!part) | 
|  | return 0; /* No partitions found */ | 
|  |  | 
|  | dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n"); | 
|  |  | 
|  | nr_parts = plen / sizeof(part[0]); | 
|  |  | 
|  | info->parts = kzalloc(nr_parts * sizeof(*info->parts), GFP_KERNEL); | 
|  | if (!info->parts) | 
|  | return -ENOMEM; | 
|  |  | 
|  | names = of_get_property(dp, "partition-names", &plen); | 
|  |  | 
|  | for (i = 0; i < nr_parts; i++) { | 
|  | info->parts[i].offset = part->offset; | 
|  | info->parts[i].size   = part->len & ~1; | 
|  | if (part->len & 1) /* bit 0 set signifies read only partition */ | 
|  | info->parts[i].mask_flags = MTD_WRITEABLE; | 
|  |  | 
|  | if (names && (plen > 0)) { | 
|  | int len = strlen(names) + 1; | 
|  |  | 
|  | info->parts[i].name = (char *)names; | 
|  | plen -= len; | 
|  | names += len; | 
|  | } else { | 
|  | info->parts[i].name = "unnamed"; | 
|  | } | 
|  |  | 
|  | part++; | 
|  | } | 
|  |  | 
|  | return nr_parts; | 
|  | } | 
|  | #else /* MTD_PARTITIONS */ | 
|  | #define	OF_FLASH_PARTS(info)		(0) | 
|  | #define parse_partitions(info, dev)	(0) | 
|  | #endif /* MTD_PARTITIONS */ | 
|  |  | 
|  | static int of_flash_remove(struct of_device *dev) | 
|  | { | 
|  | struct of_flash *info; | 
|  |  | 
|  | info = dev_get_drvdata(&dev->dev); | 
|  | if (!info) | 
|  | return 0; | 
|  | dev_set_drvdata(&dev->dev, NULL); | 
|  |  | 
|  | if (info->mtd) { | 
|  | if (OF_FLASH_PARTS(info)) { | 
|  | del_mtd_partitions(info->mtd); | 
|  | kfree(OF_FLASH_PARTS(info)); | 
|  | } else { | 
|  | del_mtd_device(info->mtd); | 
|  | } | 
|  | map_destroy(info->mtd); | 
|  | } | 
|  |  | 
|  | if (info->map.virt) | 
|  | iounmap(info->map.virt); | 
|  |  | 
|  | if (info->res) { | 
|  | release_resource(info->res); | 
|  | kfree(info->res); | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Helper function to handle probing of the obsolete "direct-mapped" | 
|  | * compatible binding, which has an extra "probe-type" property | 
|  | * describing the type of flash probe necessary. */ | 
|  | static struct mtd_info * __devinit obsolete_probe(struct of_device *dev, | 
|  | struct map_info *map) | 
|  | { | 
|  | struct device_node *dp = dev->node; | 
|  | const char *of_probe; | 
|  | struct mtd_info *mtd; | 
|  | static const char *rom_probe_types[] | 
|  | = { "cfi_probe", "jedec_probe", "map_rom"}; | 
|  | int i; | 
|  |  | 
|  | dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" " | 
|  | "flash binding\n"); | 
|  |  | 
|  | of_probe = of_get_property(dp, "probe-type", NULL); | 
|  | if (!of_probe) { | 
|  | for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) { | 
|  | mtd = do_map_probe(rom_probe_types[i], map); | 
|  | if (mtd) | 
|  | return mtd; | 
|  | } | 
|  | return NULL; | 
|  | } else if (strcmp(of_probe, "CFI") == 0) { | 
|  | return do_map_probe("cfi_probe", map); | 
|  | } else if (strcmp(of_probe, "JEDEC") == 0) { | 
|  | return do_map_probe("jedec_probe", map); | 
|  | } else { | 
|  | if (strcmp(of_probe, "ROM") != 0) | 
|  | dev_warn(&dev->dev, "obsolete_probe: don't know probe " | 
|  | "type '%s', mapping as rom\n", of_probe); | 
|  | return do_map_probe("mtd_rom", map); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int __devinit of_flash_probe(struct of_device *dev, | 
|  | const struct of_device_id *match) | 
|  | { | 
|  | #ifdef CONFIG_MTD_PARTITIONS | 
|  | static const char *part_probe_types[] | 
|  | = { "cmdlinepart", "RedBoot", NULL }; | 
|  | #endif | 
|  | struct device_node *dp = dev->node; | 
|  | struct resource res; | 
|  | struct of_flash *info; | 
|  | const char *probe_type = match->data; | 
|  | const u32 *width; | 
|  | int err; | 
|  |  | 
|  | err = -ENXIO; | 
|  | if (of_address_to_resource(dp, 0, &res)) { | 
|  | dev_err(&dev->dev, "Can't get IO address from device tree\n"); | 
|  | goto err_out; | 
|  | } | 
|  |  | 
|  | dev_dbg(&dev->dev, "of_flash device: %.8llx-%.8llx\n", | 
|  | (unsigned long long)res.start, (unsigned long long)res.end); | 
|  |  | 
|  | err = -ENOMEM; | 
|  | info = kzalloc(sizeof(*info), GFP_KERNEL); | 
|  | if (!info) | 
|  | goto err_out; | 
|  |  | 
|  | dev_set_drvdata(&dev->dev, info); | 
|  |  | 
|  | err = -EBUSY; | 
|  | info->res = request_mem_region(res.start, res.end - res.start + 1, | 
|  | dev->dev.bus_id); | 
|  | if (!info->res) | 
|  | goto err_out; | 
|  |  | 
|  | err = -ENXIO; | 
|  | width = of_get_property(dp, "bank-width", NULL); | 
|  | if (!width) { | 
|  | dev_err(&dev->dev, "Can't get bank width from device tree\n"); | 
|  | goto err_out; | 
|  | } | 
|  |  | 
|  | info->map.name = dev->dev.bus_id; | 
|  | info->map.phys = res.start; | 
|  | info->map.size = res.end - res.start + 1; | 
|  | info->map.bankwidth = *width; | 
|  |  | 
|  | err = -ENOMEM; | 
|  | info->map.virt = ioremap(info->map.phys, info->map.size); | 
|  | if (!info->map.virt) { | 
|  | dev_err(&dev->dev, "Failed to ioremap() flash region\n"); | 
|  | goto err_out; | 
|  | } | 
|  |  | 
|  | simple_map_init(&info->map); | 
|  |  | 
|  | if (probe_type) | 
|  | info->mtd = do_map_probe(probe_type, &info->map); | 
|  | else | 
|  | info->mtd = obsolete_probe(dev, &info->map); | 
|  |  | 
|  | err = -ENXIO; | 
|  | if (!info->mtd) { | 
|  | dev_err(&dev->dev, "do_map_probe() failed\n"); | 
|  | goto err_out; | 
|  | } | 
|  | info->mtd->owner = THIS_MODULE; | 
|  |  | 
|  | #ifdef CONFIG_MTD_PARTITIONS | 
|  | /* First look for RedBoot table or partitions on the command | 
|  | * line, these take precedence over device tree information */ | 
|  | err = parse_mtd_partitions(info->mtd, part_probe_types, | 
|  | &info->parts, 0); | 
|  | if (err < 0) | 
|  | return err; | 
|  |  | 
|  | #ifdef CONFIG_MTD_OF_PARTS | 
|  | if (err == 0) { | 
|  | err = of_mtd_parse_partitions(&dev->dev, info->mtd, | 
|  | dp, &info->parts); | 
|  | if (err < 0) | 
|  | return err; | 
|  | } | 
|  | #endif | 
|  |  | 
|  | if (err == 0) { | 
|  | err = parse_obsolete_partitions(dev, info, dp); | 
|  | if (err < 0) | 
|  | return err; | 
|  | } | 
|  |  | 
|  | if (err > 0) | 
|  | add_mtd_partitions(info->mtd, info->parts, err); | 
|  | else | 
|  | #endif | 
|  | add_mtd_device(info->mtd); | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | err_out: | 
|  | of_flash_remove(dev); | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static struct of_device_id of_flash_match[] = { | 
|  | { | 
|  | .compatible	= "cfi-flash", | 
|  | .data		= (void *)"cfi_probe", | 
|  | }, | 
|  | { | 
|  | /* FIXME: JEDEC chips can't be safely and reliably | 
|  | * probed, although the mtd code gets it right in | 
|  | * practice most of the time.  We should use the | 
|  | * vendor and device ids specified by the binding to | 
|  | * bypass the heuristic probe code, but the mtd layer | 
|  | * provides, at present, no interface for doing so | 
|  | * :(. */ | 
|  | .compatible	= "jedec-flash", | 
|  | .data		= (void *)"jedec_probe", | 
|  | }, | 
|  | { | 
|  | .type		= "rom", | 
|  | .compatible	= "direct-mapped" | 
|  | }, | 
|  | { }, | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(of, of_flash_match); | 
|  |  | 
|  | static struct of_platform_driver of_flash_driver = { | 
|  | .name		= "of-flash", | 
|  | .match_table	= of_flash_match, | 
|  | .probe		= of_flash_probe, | 
|  | .remove		= of_flash_remove, | 
|  | }; | 
|  |  | 
|  | static int __init of_flash_init(void) | 
|  | { | 
|  | return of_register_platform_driver(&of_flash_driver); | 
|  | } | 
|  |  | 
|  | static void __exit of_flash_exit(void) | 
|  | { | 
|  | of_unregister_platform_driver(&of_flash_driver); | 
|  | } | 
|  |  | 
|  | module_init(of_flash_init); | 
|  | module_exit(of_flash_exit); | 
|  |  | 
|  | MODULE_LICENSE("GPL"); | 
|  | MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>"); | 
|  | MODULE_DESCRIPTION("Device tree based MTD map driver"); |