| /* |
| * 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; |
| } |
| |
| static int __devinit parse_partitions(struct of_flash *info, |
| struct of_device *dev) |
| { |
| const char *partname; |
| static const char *part_probe_types[] |
| = { "cmdlinepart", "RedBoot", NULL }; |
| struct device_node *dp = dev->node, *pp; |
| int nr_parts, i; |
| |
| /* First look for RedBoot table or partitions on the command |
| * line, these take precedence over device tree information */ |
| nr_parts = parse_mtd_partitions(info->mtd, part_probe_types, |
| &info->parts, 0); |
| if (nr_parts > 0) { |
| add_mtd_partitions(info->mtd, info->parts, nr_parts); |
| return 0; |
| } |
| |
| /* First count the subnodes */ |
| nr_parts = 0; |
| for (pp = dp->child; pp; pp = pp->sibling) |
| nr_parts++; |
| |
| if (nr_parts == 0) |
| return parse_obsolete_partitions(dev, info, dp); |
| |
| info->parts = kzalloc(nr_parts * sizeof(*info->parts), |
| GFP_KERNEL); |
| if (!info->parts) |
| return -ENOMEM; |
| |
| for (pp = dp->child, i = 0; pp; pp = pp->sibling, i++) { |
| const u32 *reg; |
| int len; |
| |
| reg = of_get_property(pp, "reg", &len); |
| if (!reg || (len != 2*sizeof(u32))) { |
| dev_err(&dev->dev, "Invalid 'reg' on %s\n", |
| dp->full_name); |
| kfree(info->parts); |
| info->parts = NULL; |
| return -EINVAL; |
| } |
| info->parts[i].offset = reg[0]; |
| info->parts[i].size = reg[1]; |
| |
| partname = of_get_property(pp, "label", &len); |
| if (!partname) |
| partname = of_get_property(pp, "name", &len); |
| info->parts[i].name = (char *)partname; |
| |
| if (of_get_property(pp, "read-only", &len)) |
| info->parts[i].mask_flags = MTD_WRITEABLE; |
| } |
| |
| 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) |
| { |
| 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; |
| memset(info, 0, sizeof(*info)); |
| |
| 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; |
| |
| err = parse_partitions(info, dev); |
| if (err < 0) |
| goto err_out; |
| |
| if (err > 0) |
| add_mtd_partitions(info->mtd, OF_FLASH_PARTS(info), err); |
| else |
| 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"); |