GNU Linux-libre 4.19.286-gnu1
[releases.git] / 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");