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_platform.h>
  16 #include <linux/mtd/partitions.h>
  17
  18 #include <asm/octeon/octeon.h>
  19
  20 static struct map_info flash_map;
  21 static struct mtd_info *mymtd;
  22 static const char *part_probe_types[] = {
  23         "cmdlinepart",
  24 #ifdef CONFIG_MTD_REDBOOT_PARTS
  25         "RedBoot",
  26 #endif
  27         NULL
  28 };
  29
  30 static 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
  41 static 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
  49 static 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
  57 static 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  */
  70 static 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
 121 static const struct of_device_id of_flash_match[] = {
 122         {
 123                 .compatible     = "cfi-flash",
 124         },
 125         { },
 126 };
 127 MODULE_DEVICE_TABLE(of, of_flash_match);
 128
 129 static 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
 137 static int octeon_flash_init(void)
 138 {
 139         return platform_driver_register(&of_flash_driver);
 140 }
 141 late_initcall(octeon_flash_init);
 142
 143 MODULE_LICENSE("GPL");