1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ichxrom.c
4 *
5 * Normal mappings of chips in physical memory
6 */
7
8#include <linux/module.h>
9#include <linux/types.h>
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <asm/io.h>
14#include <linux/mtd/mtd.h>
15#include <linux/mtd/map.h>
16#include <linux/mtd/cfi.h>
17#include <linux/mtd/flashchip.h>
18#include <linux/pci.h>
19#include <linux/pci_ids.h>
20#include <linux/list.h>
21
22#define xstr(s) str(s)
23#define str(s) #s
24#define MOD_NAME xstr(KBUILD_BASENAME)
25
26#define ADDRESS_NAME_LEN 18
27
28#define ROM_PROBE_STEP_SIZE (64*1024) /* 64KiB */
29
30#define BIOS_CNTL 0x4e
31#define FWH_DEC_EN1 0xE3
32#define FWH_DEC_EN2 0xF0
33#define FWH_SEL1 0xE8
34#define FWH_SEL2 0xEE
35
36struct ichxrom_window {
37 void __iomem* virt;
38 unsigned long phys;
39 unsigned long size;
40 struct list_head maps;
41 struct resource rsrc;
42 struct pci_dev *pdev;
43};
44
45struct ichxrom_map_info {
46 struct list_head list;
47 struct map_info map;
48 struct mtd_info *mtd;
49 struct resource rsrc;
50 char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
51};
52
53static struct ichxrom_window ichxrom_window = {
54 .maps = LIST_HEAD_INIT(ichxrom_window.maps),
55};
56
57static void ichxrom_cleanup(struct ichxrom_window *window)
58{
59 struct ichxrom_map_info *map, *scratch;
60 u16 word;
61 int ret;
62
63 /* Disable writes through the rom window */
64 ret = pci_read_config_word(dev: window->pdev, BIOS_CNTL, val: &word);
65 if (!ret)
66 pci_write_config_word(dev: window->pdev, BIOS_CNTL, val: word & ~1);
67 pci_dev_put(dev: window->pdev);
68
69 /* Free all of the mtd devices */
70 list_for_each_entry_safe(map, scratch, &window->maps, list) {
71 if (map->rsrc.parent)
72 release_resource(new: &map->rsrc);
73 mtd_device_unregister(master: map->mtd);
74 map_destroy(mtd: map->mtd);
75 list_del(entry: &map->list);
76 kfree(objp: map);
77 }
78 if (window->rsrc.parent)
79 release_resource(new: &window->rsrc);
80 if (window->virt) {
81 iounmap(addr: window->virt);
82 window->virt = NULL;
83 window->phys = 0;
84 window->size = 0;
85 window->pdev = NULL;
86 }
87}
88
89
90static int __init ichxrom_init_one(struct pci_dev *pdev,
91 const struct pci_device_id *ent)
92{
93 static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
94 struct ichxrom_window *window = &ichxrom_window;
95 struct ichxrom_map_info *map = NULL;
96 unsigned long map_top;
97 u8 byte;
98 u16 word;
99
100 /* For now I just handle the ichx and I assume there
101 * are not a lot of resources up at the top of the address
102 * space. It is possible to handle other devices in the
103 * top 16MB but it is very painful. Also since
104 * you can only really attach a FWH to an ICHX there
105 * a number of simplifications you can make.
106 *
107 * Also you can page firmware hubs if an 8MB window isn't enough
108 * but don't currently handle that case either.
109 */
110 window->pdev = pdev;
111
112 /* Find a region continuous to the end of the ROM window */
113 window->phys = 0;
114 pci_read_config_byte(dev: pdev, FWH_DEC_EN1, val: &byte);
115 if (byte == 0xff) {
116 window->phys = 0xffc00000;
117 pci_read_config_byte(dev: pdev, FWH_DEC_EN2, val: &byte);
118 if ((byte & 0x0f) == 0x0f) {
119 window->phys = 0xff400000;
120 }
121 else if ((byte & 0x0e) == 0x0e) {
122 window->phys = 0xff500000;
123 }
124 else if ((byte & 0x0c) == 0x0c) {
125 window->phys = 0xff600000;
126 }
127 else if ((byte & 0x08) == 0x08) {
128 window->phys = 0xff700000;
129 }
130 }
131 else if ((byte & 0xfe) == 0xfe) {
132 window->phys = 0xffc80000;
133 }
134 else if ((byte & 0xfc) == 0xfc) {
135 window->phys = 0xffd00000;
136 }
137 else if ((byte & 0xf8) == 0xf8) {
138 window->phys = 0xffd80000;
139 }
140 else if ((byte & 0xf0) == 0xf0) {
141 window->phys = 0xffe00000;
142 }
143 else if ((byte & 0xe0) == 0xe0) {
144 window->phys = 0xffe80000;
145 }
146 else if ((byte & 0xc0) == 0xc0) {
147 window->phys = 0xfff00000;
148 }
149 else if ((byte & 0x80) == 0x80) {
150 window->phys = 0xfff80000;
151 }
152
153 if (window->phys == 0) {
154 printk(KERN_ERR MOD_NAME ": Rom window is closed\n");
155 goto out;
156 }
157 window->phys -= 0x400000UL;
158 window->size = (0xffffffffUL - window->phys) + 1UL;
159
160 /* Enable writes through the rom window */
161 pci_read_config_word(dev: pdev, BIOS_CNTL, val: &word);
162 if (!(word & 1) && (word & (1<<1))) {
163 /* The BIOS will generate an error if I enable
164 * this device, so don't even try.
165 */
166 printk(KERN_ERR MOD_NAME ": firmware access control, I can't enable writes\n");
167 goto out;
168 }
169 pci_write_config_word(dev: pdev, BIOS_CNTL, val: word | 1);
170
171 /*
172 * Try to reserve the window mem region. If this fails then
173 * it is likely due to the window being "reserved" by the BIOS.
174 */
175 window->rsrc.name = MOD_NAME;
176 window->rsrc.start = window->phys;
177 window->rsrc.end = window->phys + window->size - 1;
178 window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
179 if (request_resource(root: &iomem_resource, new: &window->rsrc)) {
180 window->rsrc.parent = NULL;
181 printk(KERN_DEBUG MOD_NAME ": "
182 "%s(): Unable to register resource %pR - kernel bug?\n",
183 __func__, &window->rsrc);
184 }
185
186 /* Map the firmware hub into my address space. */
187 window->virt = ioremap(offset: window->phys, size: window->size);
188 if (!window->virt) {
189 printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
190 window->phys, window->size);
191 goto out;
192 }
193
194 /* Get the first address to look for an rom chip at */
195 map_top = window->phys;
196 if ((window->phys & 0x3fffff) != 0) {
197 map_top = window->phys + 0x400000;
198 }
199#if 1
200 /* The probe sequence run over the firmware hub lock
201 * registers sets them to 0x7 (no access).
202 * Probe at most the last 4M of the address space.
203 */
204 if (map_top < 0xffc00000) {
205 map_top = 0xffc00000;
206 }
207#endif
208 /* Loop through and look for rom chips */
209 while((map_top - 1) < 0xffffffffUL) {
210 struct cfi_private *cfi;
211 unsigned long offset;
212 int i;
213
214 if (!map) {
215 map = kmalloc(size: sizeof(*map), GFP_KERNEL);
216 if (!map)
217 goto out;
218 }
219 memset(map, 0, sizeof(*map));
220 INIT_LIST_HEAD(list: &map->list);
221 map->map.name = map->map_name;
222 map->map.phys = map_top;
223 offset = map_top - window->phys;
224 map->map.virt = (void __iomem *)
225 (((unsigned long)(window->virt)) + offset);
226 map->map.size = 0xffffffffUL - map_top + 1UL;
227 /* Set the name of the map to the address I am trying */
228 sprintf(buf: map->map_name, fmt: "%s @%08Lx",
229 MOD_NAME, (unsigned long long)map->map.phys);
230
231 /* Firmware hubs only use vpp when being programmed
232 * in a factory setting. So in-place programming
233 * needs to use a different method.
234 */
235 for(map->map.bankwidth = 32; map->map.bankwidth;
236 map->map.bankwidth >>= 1)
237 {
238 char **probe_type;
239 /* Skip bankwidths that are not supported */
240 if (!map_bankwidth_supported(w: map->map.bankwidth))
241 continue;
242
243 /* Setup the map methods */
244 simple_map_init(&map->map);
245
246 /* Try all of the probe methods */
247 probe_type = rom_probe_types;
248 for(; *probe_type; probe_type++) {
249 map->mtd = do_map_probe(name: *probe_type, map: &map->map);
250 if (map->mtd)
251 goto found;
252 }
253 }
254 map_top += ROM_PROBE_STEP_SIZE;
255 continue;
256 found:
257 /* Trim the size if we are larger than the map */
258 if (map->mtd->size > map->map.size) {
259 printk(KERN_WARNING MOD_NAME
260 " rom(%llu) larger than window(%lu). fixing...\n",
261 (unsigned long long)map->mtd->size, map->map.size);
262 map->mtd->size = map->map.size;
263 }
264 if (window->rsrc.parent) {
265 /*
266 * Registering the MTD device in iomem may not be possible
267 * if there is a BIOS "reserved" and BUSY range. If this
268 * fails then continue anyway.
269 */
270 map->rsrc.name = map->map_name;
271 map->rsrc.start = map->map.phys;
272 map->rsrc.end = map->map.phys + map->mtd->size - 1;
273 map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
274 if (request_resource(root: &window->rsrc, new: &map->rsrc)) {
275 printk(KERN_ERR MOD_NAME
276 ": cannot reserve MTD resource\n");
277 map->rsrc.parent = NULL;
278 }
279 }
280
281 /* Make the whole region visible in the map */
282 map->map.virt = window->virt;
283 map->map.phys = window->phys;
284 cfi = map->map.fldrv_priv;
285 for(i = 0; i < cfi->numchips; i++) {
286 cfi->chips[i].start += offset;
287 }
288
289 /* Now that the mtd devices is complete claim and export it */
290 map->mtd->owner = THIS_MODULE;
291 if (mtd_device_register(map->mtd, NULL, 0)) {
292 map_destroy(mtd: map->mtd);
293 map->mtd = NULL;
294 goto out;
295 }
296
297
298 /* Calculate the new value of map_top */
299 map_top += map->mtd->size;
300
301 /* File away the map structure */
302 list_add(new: &map->list, head: &window->maps);
303 map = NULL;
304 }
305
306 out:
307 /* Free any left over map structures */
308 kfree(objp: map);
309
310 /* See if I have any map structures */
311 if (list_empty(head: &window->maps)) {
312 ichxrom_cleanup(window);
313 return -ENODEV;
314 }
315 return 0;
316}
317
318
319static void ichxrom_remove_one(struct pci_dev *pdev)
320{
321 struct ichxrom_window *window = &ichxrom_window;
322 ichxrom_cleanup(window);
323}
324
325static const struct pci_device_id ichxrom_pci_tbl[] = {
326 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0,
327 PCI_ANY_ID, PCI_ANY_ID, },
328 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0,
329 PCI_ANY_ID, PCI_ANY_ID, },
330 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
331 PCI_ANY_ID, PCI_ANY_ID, },
332 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,
333 PCI_ANY_ID, PCI_ANY_ID, },
334 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1,
335 PCI_ANY_ID, PCI_ANY_ID, },
336 { 0, },
337};
338
339#if 0
340MODULE_DEVICE_TABLE(pci, ichxrom_pci_tbl);
341
342static struct pci_driver ichxrom_driver = {
343 .name = MOD_NAME,
344 .id_table = ichxrom_pci_tbl,
345 .probe = ichxrom_init_one,
346 .remove = ichxrom_remove_one,
347};
348#endif
349
350static int __init init_ichxrom(void)
351{
352 struct pci_dev *pdev;
353 const struct pci_device_id *id;
354
355 pdev = NULL;
356 for (id = ichxrom_pci_tbl; id->vendor; id++) {
357 pdev = pci_get_device(vendor: id->vendor, device: id->device, NULL);
358 if (pdev) {
359 break;
360 }
361 }
362 if (pdev) {
363 return ichxrom_init_one(pdev, ent: &ichxrom_pci_tbl[0]);
364 }
365 return -ENXIO;
366#if 0
367 return pci_register_driver(&ichxrom_driver);
368#endif
369}
370
371static void __exit cleanup_ichxrom(void)
372{
373 ichxrom_remove_one(pdev: ichxrom_window.pdev);
374}
375
376module_init(init_ichxrom);
377module_exit(cleanup_ichxrom);
378
379MODULE_LICENSE("GPL");
380MODULE_AUTHOR("Eric Biederman <ebiederman@lnxi.com>");
381MODULE_DESCRIPTION("MTD map driver for BIOS chips on the ICHX southbridge");
382

source code of linux/drivers/mtd/maps/ichxrom.c