arch/mips/cavium-octeon/flash_setup.c

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