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");
145