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