LXR linux/arch/mips/cavium-octeon/flash

   1/*
   2 *   Octeon Bootbus flash setup
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 2007, 2008 Cavium Networks
   9 */
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <linux/semaphore.h>
  13#include <linux/mtd/mtd.h>
  14#include <linux/mtd/map.h>
  15#include <linux/of_platform.h>
  16#include <linux/mtd/partitions.h>
  17
  18#include <asm/octeon/octeon.h>
  19
  20static struct map_info flash_map;
  21static struct mtd_info *mymtd;
  22static const char *part_probe_types[] = {
  23        "cmdlinepart",
  24#ifdef CONFIG_MTD_REDBOOT_PARTS
  25        "RedBoot",
  26#endif
  27        NULL
  28};
  29
  30static map_word octeon_flash_map_read(struct map_info *map, unsigned long ofs)
  31{
  32        map_word r;
  33
  34        down(&octeon_bootbus_sem);
  35        r = inline_map_read(map, ofs);
  36        up(&octeon_bootbus_sem);
  37
  38        return r;
  39}
  40
  41static void octeon_flash_map_write(struct map_info *map, const map_word datum,
  42                                   unsigned long ofs)
  43{
  44        down(&octeon_bootbus_sem);
  45        inline_map_write(map, datum, ofs);
  46        up(&octeon_bootbus_sem);
  47}
  48
  49static void octeon_flash_map_copy_from(struct map_info *map, void *to,
  50                                       unsigned long from, ssize_t len)
  51{
  52        down(&octeon_bootbus_sem);
  53        inline_map_copy_from(map, to, from, len);
  54        up(&octeon_bootbus_sem);
  55}
  56
  57static void octeon_flash_map_copy_to(struct map_info *map, unsigned long to,
  58                                     const void *from, ssize_t len)
  59{
  60        down(&octeon_bootbus_sem);
  61        inline_map_copy_to(map, to, from, len);
  62        up(&octeon_bootbus_sem);
  63}
  64
  65/**
  66 * Module/ driver initialization.
  67 *
  68 * Returns Zero on success
  69 */
  70static int octeon_flash_probe(struct platform_device *pdev)
  71{
  72        union cvmx_mio_boot_reg_cfgx region_cfg;
  73        u32 cs;
  74        int r;
  75        struct device_node *np = pdev->dev.of_node;
  76
  77        r = of_property_read_u32(np, "reg", &cs);
  78        if (r)
  79                return r;
  80
  81        /*
  82         * Read the bootbus region 0 setup to determine the base
  83         * address of the flash.
  84         */
  85        region_cfg.u64 = cvmx_read_csr(CVMX_MIO_BOOT_REG_CFGX(cs));
  86        if (region_cfg.s.en) {
  87                /*
  88                 * The bootloader always takes the flash and sets its
  89                 * address so the entire flash fits below
  90                 * 0x1fc00000. This way the flash aliases to
  91                 * 0x1fc00000 for booting. Software can access the
  92                 * full flash at the true address, while core boot can
  93                 * access 4MB.
  94                 */
  95                /* Use this name so old part lines work */
  96                flash_map.name = "phys_mapped_flash";
  97                flash_map.phys = region_cfg.s.base << 16;
  98                flash_map.size = 0x1fc00000 - flash_map.phys;
  99                /* 8-bit bus (0 + 1) or 16-bit bus (1 + 1) */
 100                flash_map.bankwidth = region_cfg.s.width + 1;
 101                flash_map.virt = ioremap(flash_map.phys, flash_map.size);
 102                pr_notice("Bootbus flash: Setting flash for %luMB flash at "
 103                          "0x%08llx\n", flash_map.size >> 20, flash_map.phys);
 104                WARN_ON(!map_bankwidth_supported(flash_map.bankwidth));
 105                flash_map.read = octeon_flash_map_read;
 106                flash_map.write = octeon_flash_map_write;
 107                flash_map.copy_from = octeon_flash_map_copy_from;
 108                flash_map.copy_to = octeon_flash_map_copy_to;
 109                mymtd = do_map_probe("cfi_probe", &flash_map);
 110                if (mymtd) {
 111                        mymtd->owner = THIS_MODULE;
 112                        mtd_device_parse_register(mymtd, part_probe_types,
 113                                                  NULL, NULL, 0);
 114                } else {
 115                        pr_err("Failed to register MTD device for flash\n");
 116                }
 117        }
 118        return 0;
 119}
 120
 121static const struct of_device_id of_flash_match[] = {
 122        {
 123                .compatible     = "cfi-flash",
 124        },
 125        { },
 126};
 127MODULE_DEVICE_TABLE(of, of_flash_match);
 128
 129static struct platform_driver of_flash_driver = {
 130        .driver = {
 131                .name = "octeon-of-flash",
 132                .of_match_table = of_flash_match,
 133        },
 134        .probe          = octeon_flash_probe,
 135};
 136
 137static int octeon_flash_init(void)
 138{
 139        return platform_driver_register(&of_flash_driver);
 140}
 141late_initcall(octeon_flash_init);
 142
 143MODULE_LICENSE("GPL");
 144