Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* sc520cdp.c -- MTD map driver for AMD SC520 Customer Development Platform |
2 | * | |
3 | * Copyright (C) 2001 Sysgo Real-Time Solutions GmbH | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA | |
18 | * | |
19 | * $Id: sc520cdp.c,v 1.21 2004/12/13 10:27:08 dedekind Exp $ | |
20 | * | |
21 | * | |
22 | * The SC520CDP is an evaluation board for the Elan SC520 processor available | |
23 | * from AMD. It has two banks of 32-bit Flash ROM, each 8 Megabytes in size, | |
24 | * and up to 512 KiB of 8-bit DIL Flash ROM. | |
25 | * For details see http://www.amd.com/products/epd/desiging/evalboards/18.elansc520/520_cdp_brief/index.html | |
26 | */ | |
27 | ||
28 | #include <linux/config.h> | |
29 | #include <linux/module.h> | |
30 | #include <linux/types.h> | |
31 | #include <linux/kernel.h> | |
32 | #include <linux/init.h> | |
33 | #include <asm/io.h> | |
34 | #include <linux/mtd/mtd.h> | |
35 | #include <linux/mtd/map.h> | |
36 | #include <linux/mtd/concat.h> | |
37 | ||
38 | /* | |
39 | ** The Embedded Systems BIOS decodes the first FLASH starting at | |
40 | ** 0x8400000. This is a *terrible* place for it because accessing | |
41 | ** the flash at this location causes the A22 address line to be high | |
42 | ** (that's what 0x8400000 binary's ought to be). But this is the highest | |
43 | ** order address line on the raw flash devices themselves!! | |
44 | ** This causes the top HALF of the flash to be accessed first. Beyond | |
45 | ** the physical limits of the flash, the flash chip aliases over (to | |
46 | ** 0x880000 which causes the bottom half to be accessed. This splits the | |
47 | ** flash into two and inverts it! If you then try to access this from another | |
48 | ** program that does NOT do this insanity, then you *will* access the | |
49 | ** first half of the flash, but not find what you expect there. That | |
50 | ** stuff is in the *second* half! Similarly, the address used by the | |
51 | ** BIOS for the second FLASH bank is also quite a bad choice. | |
52 | ** If REPROGRAM_PAR is defined below (the default), then this driver will | |
53 | ** choose more useful addresses for the FLASH banks by reprogramming the | |
54 | ** responsible PARxx registers in the SC520's MMCR region. This will | |
55 | ** cause the settings to be incompatible with the BIOS's settings, which | |
56 | ** shouldn't be a problem since you are running Linux, (i.e. the BIOS is | |
57 | ** not much use anyway). However, if you need to be compatible with | |
58 | ** the BIOS for some reason, just undefine REPROGRAM_PAR. | |
59 | */ | |
60 | #define REPROGRAM_PAR | |
61 | ||
62 | ||
63 | ||
64 | #ifdef REPROGRAM_PAR | |
65 | ||
66 | /* These are the addresses we want.. */ | |
67 | #define WINDOW_ADDR_0 0x08800000 | |
68 | #define WINDOW_ADDR_1 0x09000000 | |
69 | #define WINDOW_ADDR_2 0x09800000 | |
70 | ||
71 | /* .. and these are the addresses the BIOS gives us */ | |
72 | #define WINDOW_ADDR_0_BIOS 0x08400000 | |
73 | #define WINDOW_ADDR_1_BIOS 0x08c00000 | |
74 | #define WINDOW_ADDR_2_BIOS 0x09400000 | |
75 | ||
76 | #else | |
77 | ||
78 | #define WINDOW_ADDR_0 0x08400000 | |
79 | #define WINDOW_ADDR_1 0x08C00000 | |
80 | #define WINDOW_ADDR_2 0x09400000 | |
81 | ||
82 | #endif | |
83 | ||
84 | #define WINDOW_SIZE_0 0x00800000 | |
85 | #define WINDOW_SIZE_1 0x00800000 | |
86 | #define WINDOW_SIZE_2 0x00080000 | |
87 | ||
88 | ||
89 | static struct map_info sc520cdp_map[] = { | |
90 | { | |
91 | .name = "SC520CDP Flash Bank #0", | |
92 | .size = WINDOW_SIZE_0, | |
93 | .bankwidth = 4, | |
94 | .phys = WINDOW_ADDR_0 | |
95 | }, | |
96 | { | |
97 | .name = "SC520CDP Flash Bank #1", | |
98 | .size = WINDOW_SIZE_1, | |
99 | .bankwidth = 4, | |
100 | .phys = WINDOW_ADDR_1 | |
101 | }, | |
102 | { | |
103 | .name = "SC520CDP DIL Flash", | |
104 | .size = WINDOW_SIZE_2, | |
105 | .bankwidth = 1, | |
106 | .phys = WINDOW_ADDR_2 | |
107 | }, | |
108 | }; | |
109 | ||
110 | #define NUM_FLASH_BANKS (sizeof(sc520cdp_map)/sizeof(struct map_info)) | |
111 | ||
112 | static struct mtd_info *mymtd[NUM_FLASH_BANKS]; | |
113 | static struct mtd_info *merged_mtd; | |
114 | ||
115 | #ifdef REPROGRAM_PAR | |
116 | ||
117 | /* | |
118 | ** The SC520 MMCR (memory mapped control register) region resides | |
119 | ** at 0xFFFEF000. The 16 Programmable Address Region (PAR) registers | |
120 | ** are at offset 0x88 in the MMCR: | |
121 | */ | |
122 | #define SC520_MMCR_BASE 0xFFFEF000 | |
123 | #define SC520_MMCR_EXTENT 0x1000 | |
124 | #define SC520_PAR(x) ((0x88/sizeof(unsigned long)) + (x)) | |
125 | #define NUM_SC520_PAR 16 /* total number of PAR registers */ | |
126 | ||
127 | /* | |
128 | ** The highest three bits in a PAR register determine what target | |
129 | ** device is controlled by this PAR. Here, only ROMCS? and BOOTCS | |
130 | ** devices are of interest. | |
131 | */ | |
132 | #define SC520_PAR_BOOTCS (0x4<<29) | |
133 | #define SC520_PAR_ROMCS0 (0x5<<29) | |
134 | #define SC520_PAR_ROMCS1 (0x6<<29) | |
135 | #define SC520_PAR_TRGDEV (0x7<<29) | |
136 | ||
137 | /* | |
138 | ** Bits 28 thru 26 determine some attributes for the | |
139 | ** region controlled by the PAR. (We only use non-cacheable) | |
140 | */ | |
141 | #define SC520_PAR_WRPROT (1<<26) /* write protected */ | |
142 | #define SC520_PAR_NOCACHE (1<<27) /* non-cacheable */ | |
143 | #define SC520_PAR_NOEXEC (1<<28) /* code execution denied */ | |
144 | ||
145 | ||
146 | /* | |
147 | ** Bit 25 determines the granularity: 4K or 64K | |
148 | */ | |
149 | #define SC520_PAR_PG_SIZ4 (0<<25) | |
150 | #define SC520_PAR_PG_SIZ64 (1<<25) | |
151 | ||
152 | /* | |
153 | ** Build a value to be written into a PAR register. | |
154 | ** We only need ROM entries, 64K page size: | |
155 | */ | |
156 | #define SC520_PAR_ENTRY(trgdev, address, size) \ | |
157 | ((trgdev) | SC520_PAR_NOCACHE | SC520_PAR_PG_SIZ64 | \ | |
158 | (address) >> 16 | (((size) >> 16) - 1) << 14) | |
159 | ||
160 | struct sc520_par_table | |
161 | { | |
162 | unsigned long trgdev; | |
163 | unsigned long new_par; | |
164 | unsigned long default_address; | |
165 | }; | |
166 | ||
167 | static struct sc520_par_table par_table[NUM_FLASH_BANKS] = | |
168 | { | |
169 | { /* Flash Bank #0: selected by ROMCS0 */ | |
170 | SC520_PAR_ROMCS0, | |
171 | SC520_PAR_ENTRY(SC520_PAR_ROMCS0, WINDOW_ADDR_0, WINDOW_SIZE_0), | |
172 | WINDOW_ADDR_0_BIOS | |
173 | }, | |
174 | { /* Flash Bank #1: selected by ROMCS1 */ | |
175 | SC520_PAR_ROMCS1, | |
176 | SC520_PAR_ENTRY(SC520_PAR_ROMCS1, WINDOW_ADDR_1, WINDOW_SIZE_1), | |
177 | WINDOW_ADDR_1_BIOS | |
178 | }, | |
179 | { /* DIL (BIOS) Flash: selected by BOOTCS */ | |
180 | SC520_PAR_BOOTCS, | |
181 | SC520_PAR_ENTRY(SC520_PAR_BOOTCS, WINDOW_ADDR_2, WINDOW_SIZE_2), | |
182 | WINDOW_ADDR_2_BIOS | |
183 | } | |
184 | }; | |
185 | ||
186 | ||
187 | static void sc520cdp_setup_par(void) | |
188 | { | |
189 | volatile unsigned long __iomem *mmcr; | |
190 | unsigned long mmcr_val; | |
191 | int i, j; | |
192 | ||
193 | /* map in SC520's MMCR area */ | |
194 | mmcr = ioremap_nocache(SC520_MMCR_BASE, SC520_MMCR_EXTENT); | |
195 | if(!mmcr) { /* ioremap_nocache failed: skip the PAR reprogramming */ | |
196 | /* force physical address fields to BIOS defaults: */ | |
197 | for(i = 0; i < NUM_FLASH_BANKS; i++) | |
198 | sc520cdp_map[i].phys = par_table[i].default_address; | |
199 | return; | |
200 | } | |
201 | ||
202 | /* | |
203 | ** Find the PARxx registers that are reponsible for activating | |
204 | ** ROMCS0, ROMCS1 and BOOTCS. Reprogram each of these with a | |
205 | ** new value from the table. | |
206 | */ | |
207 | for(i = 0; i < NUM_FLASH_BANKS; i++) { /* for each par_table entry */ | |
208 | for(j = 0; j < NUM_SC520_PAR; j++) { /* for each PAR register */ | |
209 | mmcr_val = mmcr[SC520_PAR(j)]; | |
210 | /* if target device field matches, reprogram the PAR */ | |
211 | if((mmcr_val & SC520_PAR_TRGDEV) == par_table[i].trgdev) | |
212 | { | |
213 | mmcr[SC520_PAR(j)] = par_table[i].new_par; | |
214 | break; | |
215 | } | |
216 | } | |
217 | if(j == NUM_SC520_PAR) | |
218 | { /* no matching PAR found: try default BIOS address */ | |
219 | printk(KERN_NOTICE "Could not find PAR responsible for %s\n", | |
220 | sc520cdp_map[i].name); | |
221 | printk(KERN_NOTICE "Trying default address 0x%lx\n", | |
222 | par_table[i].default_address); | |
223 | sc520cdp_map[i].phys = par_table[i].default_address; | |
224 | } | |
225 | } | |
226 | iounmap(mmcr); | |
227 | } | |
228 | #endif | |
229 | ||
230 | ||
231 | static int __init init_sc520cdp(void) | |
232 | { | |
233 | int i, devices_found = 0; | |
234 | ||
235 | #ifdef REPROGRAM_PAR | |
236 | /* reprogram PAR registers so flash appears at the desired addresses */ | |
237 | sc520cdp_setup_par(); | |
238 | #endif | |
239 | ||
240 | for (i = 0; i < NUM_FLASH_BANKS; i++) { | |
241 | printk(KERN_NOTICE "SC520 CDP flash device: 0x%lx at 0x%lx\n", | |
242 | sc520cdp_map[i].size, sc520cdp_map[i].phys); | |
243 | ||
244 | sc520cdp_map[i].virt = ioremap_nocache(sc520cdp_map[i].phys, sc520cdp_map[i].size); | |
245 | ||
246 | if (!sc520cdp_map[i].virt) { | |
247 | printk("Failed to ioremap_nocache\n"); | |
248 | return -EIO; | |
249 | } | |
250 | ||
251 | simple_map_init(&sc520cdp_map[i]); | |
252 | ||
253 | mymtd[i] = do_map_probe("cfi_probe", &sc520cdp_map[i]); | |
254 | if(!mymtd[i]) | |
255 | mymtd[i] = do_map_probe("jedec_probe", &sc520cdp_map[i]); | |
256 | if(!mymtd[i]) | |
257 | mymtd[i] = do_map_probe("map_rom", &sc520cdp_map[i]); | |
258 | ||
259 | if (mymtd[i]) { | |
260 | mymtd[i]->owner = THIS_MODULE; | |
261 | ++devices_found; | |
262 | } | |
263 | else { | |
264 | iounmap(sc520cdp_map[i].virt); | |
265 | } | |
266 | } | |
267 | if(devices_found >= 2) { | |
268 | /* Combine the two flash banks into a single MTD device & register it: */ | |
269 | merged_mtd = mtd_concat_create(mymtd, 2, "SC520CDP Flash Banks #0 and #1"); | |
270 | if(merged_mtd) | |
271 | add_mtd_device(merged_mtd); | |
272 | } | |
273 | if(devices_found == 3) /* register the third (DIL-Flash) device */ | |
274 | add_mtd_device(mymtd[2]); | |
275 | return(devices_found ? 0 : -ENXIO); | |
276 | } | |
277 | ||
278 | static void __exit cleanup_sc520cdp(void) | |
279 | { | |
280 | int i; | |
281 | ||
282 | if (merged_mtd) { | |
283 | del_mtd_device(merged_mtd); | |
284 | mtd_concat_destroy(merged_mtd); | |
285 | } | |
286 | if (mymtd[2]) | |
287 | del_mtd_device(mymtd[2]); | |
288 | ||
289 | for (i = 0; i < NUM_FLASH_BANKS; i++) { | |
290 | if (mymtd[i]) | |
291 | map_destroy(mymtd[i]); | |
292 | if (sc520cdp_map[i].virt) { | |
293 | iounmap(sc520cdp_map[i].virt); | |
294 | sc520cdp_map[i].virt = NULL; | |
295 | } | |
296 | } | |
297 | } | |
298 | ||
299 | module_init(init_sc520cdp); | |
300 | module_exit(cleanup_sc520cdp); | |
301 | ||
302 | MODULE_LICENSE("GPL"); | |
303 | MODULE_AUTHOR("Sysgo Real-Time Solutions GmbH"); | |
304 | MODULE_DESCRIPTION("MTD map driver for AMD SC520 Customer Development Platform"); |