xref: /openbmc/linux/drivers/mtd/maps/netsc520.c (revision dc6a81c3)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* netsc520.c -- MTD map driver for AMD NetSc520 Demonstration Board
3  *
4  * Copyright (C) 2001 Mark Langsdorf (mark.langsdorf@amd.com)
5  *	based on sc520cdp.c by Sysgo Real-Time Solutions GmbH
6  *
7  * The NetSc520 is a demonstration board for the Elan Sc520 processor available
8  * from AMD.  It has a single back of 16 megs of 32-bit Flash ROM and another
9  * 16 megs of SDRAM.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <asm/io.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/map.h>
19 #include <linux/mtd/partitions.h>
20 
21 
22 /*
23 ** The single, 16 megabyte flash bank is divided into four virtual
24 ** partitions.  The first partition is 768 KiB and is intended to
25 ** store the kernel image loaded by the bootstrap loader.  The second
26 ** partition is 256 KiB and holds the BIOS image.  The third
27 ** partition is 14.5 MiB and is intended for the flash file system
28 ** image.  The last partition is 512 KiB and contains another copy
29 ** of the BIOS image and the reset vector.
30 **
31 ** Only the third partition should be mounted.  The first partition
32 ** should not be mounted, but it can erased and written to using the
33 ** MTD character routines.  The second and fourth partitions should
34 ** not be touched - it is possible to corrupt the BIOS image by
35 ** mounting these partitions, and potentially the board will not be
36 ** recoverable afterwards.
37 */
38 
39 /* partition_info gives details on the logical partitions that the split the
40  * single flash device into. If the size if zero we use up to the end of the
41  * device. */
42 static const struct mtd_partition partition_info[] = {
43     {
44 	    .name = "NetSc520 boot kernel",
45 	    .offset = 0,
46 	    .size = 0xc0000
47     },
48     {
49 	    .name = "NetSc520 Low BIOS",
50 	    .offset = 0xc0000,
51 	    .size = 0x40000
52     },
53     {
54 	    .name = "NetSc520 file system",
55 	    .offset = 0x100000,
56 	    .size = 0xe80000
57     },
58     {
59 	    .name = "NetSc520 High BIOS",
60 	    .offset = 0xf80000,
61 	    .size = 0x80000
62     },
63 };
64 #define NUM_PARTITIONS ARRAY_SIZE(partition_info)
65 
66 #define WINDOW_SIZE	0x00100000
67 #define WINDOW_ADDR	0x00200000
68 
69 static struct map_info netsc520_map = {
70 	.name = "netsc520 Flash Bank",
71 	.size = WINDOW_SIZE,
72 	.bankwidth = 4,
73 	.phys = WINDOW_ADDR,
74 };
75 
76 #define NUM_FLASH_BANKS	ARRAY_SIZE(netsc520_map)
77 
78 static struct mtd_info *mymtd;
79 
80 static int __init init_netsc520(void)
81 {
82 	printk(KERN_NOTICE "NetSc520 flash device: 0x%Lx at 0x%Lx\n",
83 			(unsigned long long)netsc520_map.size,
84 			(unsigned long long)netsc520_map.phys);
85 	netsc520_map.virt = ioremap(netsc520_map.phys, netsc520_map.size);
86 
87 	if (!netsc520_map.virt) {
88 		printk("Failed to ioremap\n");
89 		return -EIO;
90 	}
91 
92 	simple_map_init(&netsc520_map);
93 
94 	mymtd = do_map_probe("cfi_probe", &netsc520_map);
95 	if(!mymtd)
96 		mymtd = do_map_probe("map_ram", &netsc520_map);
97 	if(!mymtd)
98 		mymtd = do_map_probe("map_rom", &netsc520_map);
99 
100 	if (!mymtd) {
101 		iounmap(netsc520_map.virt);
102 		return -ENXIO;
103 	}
104 
105 	mymtd->owner = THIS_MODULE;
106 	mtd_device_register(mymtd, partition_info, NUM_PARTITIONS);
107 	return 0;
108 }
109 
110 static void __exit cleanup_netsc520(void)
111 {
112 	if (mymtd) {
113 		mtd_device_unregister(mymtd);
114 		map_destroy(mymtd);
115 	}
116 	if (netsc520_map.virt) {
117 		iounmap(netsc520_map.virt);
118 		netsc520_map.virt = NULL;
119 	}
120 }
121 
122 module_init(init_netsc520);
123 module_exit(cleanup_netsc520);
124 
125 MODULE_LICENSE("GPL");
126 MODULE_AUTHOR("Mark Langsdorf <mark.langsdorf@amd.com>");
127 MODULE_DESCRIPTION("MTD map driver for AMD NetSc520 Demonstration Board");
128