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
 21static struct map_info flash_map;
 22static struct mtd_info *mymtd;
 23static const char *part_probe_types[] = {
 24	"cmdlinepart",
 25#ifdef CONFIG_MTD_REDBOOT_PARTS
 26	"RedBoot",
 27#endif
 28	NULL
 29};
 30
 31static 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
 42static 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
 50static 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
 58static 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 */
 71static 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
122static const struct of_device_id of_flash_match[] = {
123	{
124		.compatible	= "cfi-flash",
125	},
126	{ },
127};
128MODULE_DEVICE_TABLE(of, of_flash_match);
129
130static 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
138static int octeon_flash_init(void)
139{
140	return platform_driver_register(&of_flash_driver);
141}
142late_initcall(octeon_flash_init);
143
144MODULE_LICENSE("GPL");