tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * $Id: walnut.c,v 1.3 2005/11/07 11:14:29 gleixner Exp $
3 *
4 * Mapping for Walnut flash
5 * (used ebony.c as a "framework")
6 *
7 * Heikki Lindholm <holindho@infradead.org>
8 *
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 */
15
16#include <linux/module.h>
17#include <linux/types.h>
18#include <linux/kernel.h>
19#include <linux/init.h>
20#include <linux/mtd/mtd.h>
21#include <linux/mtd/map.h>
22#include <linux/mtd/partitions.h>
23#include <linux/config.h>
24#include <asm/io.h>
25#include <asm/ibm4xx.h>
26#include <platforms/4xx/walnut.h>
27
28/* these should be in platforms/4xx/walnut.h ? */
29#define WALNUT_FLASH_ONBD_N(x) (x & 0x02)
30#define WALNUT_FLASH_SRAM_SEL(x) (x & 0x01)
31#define WALNUT_FLASH_LOW 0xFFF00000
32#define WALNUT_FLASH_HIGH 0xFFF80000
33#define WALNUT_FLASH_SIZE 0x80000
34
35static struct mtd_info *flash;
36
37static struct map_info walnut_map = {
38 .name = "Walnut flash",
39 .size = WALNUT_FLASH_SIZE,
40 .bankwidth = 1,
41};
42
43/* Actually, OpenBIOS is the last 128 KiB of the flash - better
44 * partitioning could be made */
45static struct mtd_partition walnut_partitions[] = {
46 {
47 .name = "OpenBIOS",
48 .offset = 0x0,
49 .size = WALNUT_FLASH_SIZE,
50 /*.mask_flags = MTD_WRITEABLE, */ /* force read-only */
51 }
52};
53
54int __init init_walnut(void)
55{
56 u8 fpga_brds1;
57 void *fpga_brds1_adr;
58 void *fpga_status_adr;
59 unsigned long flash_base;
60
61 /* this should already be mapped (platform/4xx/walnut.c) */
62 fpga_status_adr = ioremap(WALNUT_FPGA_BASE, 8);
63 if (!fpga_status_adr)
64 return -ENOMEM;
65
66 fpga_brds1_adr = fpga_status_adr+5;
67 fpga_brds1 = readb(fpga_brds1_adr);
68 /* iounmap(fpga_status_adr); */
69
70 if (WALNUT_FLASH_ONBD_N(fpga_brds1)) {
71 printk("The on-board flash is disabled (U79 sw 5)!");
72 return -EIO;
73 }
74 if (WALNUT_FLASH_SRAM_SEL(fpga_brds1))
75 flash_base = WALNUT_FLASH_LOW;
76 else
77 flash_base = WALNUT_FLASH_HIGH;
78
79 walnut_map.phys = flash_base;
80 walnut_map.virt =
81 (void __iomem *)ioremap(flash_base, walnut_map.size);
82
83 if (!walnut_map.virt) {
84 printk("Failed to ioremap flash.\n");
85 return -EIO;
86 }
87
88 simple_map_init(&walnut_map);
89
90 flash = do_map_probe("jedec_probe", &walnut_map);
91 if (flash) {
92 flash->owner = THIS_MODULE;
93 add_mtd_partitions(flash, walnut_partitions,
94 ARRAY_SIZE(walnut_partitions));
95 } else {
96 printk("map probe failed for flash\n");
97 return -ENXIO;
98 }
99
100 return 0;
101}
102
103static void __exit cleanup_walnut(void)
104{
105 if (flash) {
106 del_mtd_partitions(flash);
107 map_destroy(flash);
108 }
109
110 if (walnut_map.virt) {
111 iounmap((void *)walnut_map.virt);
112 walnut_map.virt = 0;
113 }
114}
115
116module_init(init_walnut);
117module_exit(cleanup_walnut);
118
119MODULE_LICENSE("GPL");
120MODULE_AUTHOR("Heikki Lindholm <holindho@infradead.org>");
121MODULE_DESCRIPTION("MTD map and partitions for IBM 405GP Walnut boards");