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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/mtd/maps/scb2_flash.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/mtd/maps/scb2_flash.c')
-rw-r--r--drivers/mtd/maps/scb2_flash.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/mtd/maps/scb2_flash.c b/drivers/mtd/maps/scb2_flash.c
new file mode 100644
index 000000000000..5bb3b600e5d0
--- /dev/null
+++ b/drivers/mtd/maps/scb2_flash.c
@@ -0,0 +1,256 @@
1/*
2 * MTD map driver for BIOS Flash on Intel SCB2 boards
3 * $Id: scb2_flash.c,v 1.11 2004/11/28 09:40:40 dwmw2 Exp $
4 * Copyright (C) 2002 Sun Microsystems, Inc.
5 * Tim Hockin <thockin@sun.com>
6 *
7 * A few notes on this MTD map:
8 *
9 * This was developed with a small number of SCB2 boards to test on.
10 * Hopefully, Intel has not introducted too many unaccounted variables in the
11 * making of this board.
12 *
13 * The BIOS marks its own memory region as 'reserved' in the e820 map. We
14 * try to request it here, but if it fails, we carry on anyway.
15 *
16 * This is how the chip is attached, so said the schematic:
17 * * a 4 MiB (32 Mib) 16 bit chip
18 * * a 1 MiB memory region
19 * * A20 and A21 pulled up
20 * * D8-D15 ignored
21 * What this means is that, while we are addressing bytes linearly, we are
22 * really addressing words, and discarding the other byte. This means that
23 * the chip MUST BE at least 2 MiB. This also means that every block is
24 * actually half as big as the chip reports. It also means that accesses of
25 * logical address 0 hit higher-address sections of the chip, not physical 0.
26 * One can only hope that these 4MiB x16 chips were a lot cheaper than 1MiB x8
27 * chips.
28 *
29 * This driver assumes the chip is not write-protected by an external signal.
30 * As of the this writing, that is true, but may change, just to spite me.
31 *
32 * The actual BIOS layout has been mostly reverse engineered. Intel BIOS
33 * updates for this board include 10 related (*.bio - &.bi9) binary files and
34 * another separate (*.bbo) binary file. The 10 files are 64k of data + a
35 * small header. If the headers are stripped off, the 10 64k files can be
36 * concatenated into a 640k image. This is your BIOS image, proper. The
37 * separate .bbo file also has a small header. It is the 'Boot Block'
38 * recovery BIOS. Once the header is stripped, no further prep is needed.
39 * As best I can tell, the BIOS is arranged as such:
40 * offset 0x00000 to 0x4ffff (320k): unknown - SCSI BIOS, etc?
41 * offset 0x50000 to 0xeffff (640k): BIOS proper
42 * offset 0xf0000 ty 0xfffff (64k): Boot Block region
43 *
44 * Intel's BIOS update program flashes the BIOS and Boot Block in separate
45 * steps. Probably a wise thing to do.
46 */
47
48#include <linux/module.h>
49#include <linux/types.h>
50#include <linux/kernel.h>
51#include <linux/init.h>
52#include <asm/io.h>
53#include <linux/mtd/mtd.h>
54#include <linux/mtd/map.h>
55#include <linux/mtd/cfi.h>
56#include <linux/config.h>
57#include <linux/pci.h>
58#include <linux/pci_ids.h>
59
60#define MODNAME "scb2_flash"
61#define SCB2_ADDR 0xfff00000
62#define SCB2_WINDOW 0x00100000
63
64
65static void __iomem *scb2_ioaddr;
66static struct mtd_info *scb2_mtd;
67static struct map_info scb2_map = {
68 .name = "SCB2 BIOS Flash",
69 .size = 0,
70 .bankwidth = 1,
71};
72static int region_fail;
73
74static int __devinit
75scb2_fixup_mtd(struct mtd_info *mtd)
76{
77 int i;
78 int done = 0;
79 struct map_info *map = mtd->priv;
80 struct cfi_private *cfi = map->fldrv_priv;
81
82 /* barf if this doesn't look right */
83 if (cfi->cfiq->InterfaceDesc != 1) {
84 printk(KERN_ERR MODNAME ": unsupported InterfaceDesc: %#x\n",
85 cfi->cfiq->InterfaceDesc);
86 return -1;
87 }
88
89 /* I wasn't here. I didn't see. dwmw2. */
90
91 /* the chip is sometimes bigger than the map - what a waste */
92 mtd->size = map->size;
93
94 /*
95 * We only REALLY get half the chip, due to the way it is
96 * wired up - D8-D15 are tossed away. We read linear bytes,
97 * but in reality we are getting 1/2 of each 16-bit read,
98 * which LOOKS linear to us. Because CFI code accounts for
99 * things like lock/unlock/erase by eraseregions, we need to
100 * fudge them to reflect this. Erases go like this:
101 * * send an erase to an address
102 * * the chip samples the address and erases the block
103 * * add the block erasesize to the address and repeat
104 * -- the problem is that addresses are 16-bit addressable
105 * -- we end up erasing every-other block
106 */
107 mtd->erasesize /= 2;
108 for (i = 0; i < mtd->numeraseregions; i++) {
109 struct mtd_erase_region_info *region = &mtd->eraseregions[i];
110 region->erasesize /= 2;
111 }
112
113 /*
114 * If the chip is bigger than the map, it is wired with the high
115 * address lines pulled up. This makes us access the top portion of
116 * the chip, so all our erase-region info is wrong. Start cutting from
117 * the bottom.
118 */
119 for (i = 0; !done && i < mtd->numeraseregions; i++) {
120 struct mtd_erase_region_info *region = &mtd->eraseregions[i];
121
122 if (region->numblocks * region->erasesize > mtd->size) {
123 region->numblocks = (mtd->size / region->erasesize);
124 done = 1;
125 } else {
126 region->numblocks = 0;
127 }
128 region->offset = 0;
129 }
130
131 return 0;
132}
133
134/* CSB5's 'Function Control Register' has bits for decoding @ >= 0xffc00000 */
135#define CSB5_FCR 0x41
136#define CSB5_FCR_DECODE_ALL 0x0e
137static int __devinit
138scb2_flash_probe(struct pci_dev *dev, const struct pci_device_id *ent)
139{
140 u8 reg;
141
142 /* enable decoding of the flash region in the south bridge */
143 pci_read_config_byte(dev, CSB5_FCR, &reg);
144 pci_write_config_byte(dev, CSB5_FCR, reg | CSB5_FCR_DECODE_ALL);
145
146 if (!request_mem_region(SCB2_ADDR, SCB2_WINDOW, scb2_map.name)) {
147 /*
148 * The BIOS seems to mark the flash region as 'reserved'
149 * in the e820 map. Warn and go about our business.
150 */
151 printk(KERN_WARNING MODNAME
152 ": warning - can't reserve rom window, continuing\n");
153 region_fail = 1;
154 }
155
156 /* remap the IO window (w/o caching) */
157 scb2_ioaddr = ioremap_nocache(SCB2_ADDR, SCB2_WINDOW);
158 if (!scb2_ioaddr) {
159 printk(KERN_ERR MODNAME ": Failed to ioremap window!\n");
160 if (!region_fail)
161 release_mem_region(SCB2_ADDR, SCB2_WINDOW);
162 return -ENOMEM;
163 }
164
165 scb2_map.phys = SCB2_ADDR;
166 scb2_map.virt = scb2_ioaddr;
167 scb2_map.size = SCB2_WINDOW;
168
169 simple_map_init(&scb2_map);
170
171 /* try to find a chip */
172 scb2_mtd = do_map_probe("cfi_probe", &scb2_map);
173
174 if (!scb2_mtd) {
175 printk(KERN_ERR MODNAME ": flash probe failed!\n");
176 iounmap(scb2_ioaddr);
177 if (!region_fail)
178 release_mem_region(SCB2_ADDR, SCB2_WINDOW);
179 return -ENODEV;
180 }
181
182 scb2_mtd->owner = THIS_MODULE;
183 if (scb2_fixup_mtd(scb2_mtd) < 0) {
184 del_mtd_device(scb2_mtd);
185 map_destroy(scb2_mtd);
186 iounmap(scb2_ioaddr);
187 if (!region_fail)
188 release_mem_region(SCB2_ADDR, SCB2_WINDOW);
189 return -ENODEV;
190 }
191
192 printk(KERN_NOTICE MODNAME ": chip size 0x%x at offset 0x%x\n",
193 scb2_mtd->size, SCB2_WINDOW - scb2_mtd->size);
194
195 add_mtd_device(scb2_mtd);
196
197 return 0;
198}
199
200static void __devexit
201scb2_flash_remove(struct pci_dev *dev)
202{
203 if (!scb2_mtd)
204 return;
205
206 /* disable flash writes */
207 if (scb2_mtd->lock)
208 scb2_mtd->lock(scb2_mtd, 0, scb2_mtd->size);
209
210 del_mtd_device(scb2_mtd);
211 map_destroy(scb2_mtd);
212
213 iounmap(scb2_ioaddr);
214 scb2_ioaddr = NULL;
215
216 if (!region_fail)
217 release_mem_region(SCB2_ADDR, SCB2_WINDOW);
218 pci_set_drvdata(dev, NULL);
219}
220
221static struct pci_device_id scb2_flash_pci_ids[] = {
222 {
223 .vendor = PCI_VENDOR_ID_SERVERWORKS,
224 .device = PCI_DEVICE_ID_SERVERWORKS_CSB5,
225 .subvendor = PCI_ANY_ID,
226 .subdevice = PCI_ANY_ID
227 },
228 { 0, }
229};
230
231static struct pci_driver scb2_flash_driver = {
232 .name = "Intel SCB2 BIOS Flash",
233 .id_table = scb2_flash_pci_ids,
234 .probe = scb2_flash_probe,
235 .remove = __devexit_p(scb2_flash_remove),
236};
237
238static int __init
239scb2_flash_init(void)
240{
241 return pci_module_init(&scb2_flash_driver);
242}
243
244static void __exit
245scb2_flash_exit(void)
246{
247 pci_unregister_driver(&scb2_flash_driver);
248}
249
250module_init(scb2_flash_init);
251module_exit(scb2_flash_exit);
252
253MODULE_LICENSE("GPL");
254MODULE_AUTHOR("Tim Hockin <thockin@sun.com>");
255MODULE_DESCRIPTION("MTD map driver for Intel SCB2 BIOS Flash");
256MODULE_DEVICE_TABLE(pci, scb2_flash_pci_ids);