1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * esb2rom.c
4 *
5 * Normal mappings of flash chips in physical memory
6 * through the Intel ESB2 Southbridge.
7 *
8 * This was derived from ichxrom.c in May 2006 by
9 * Lew Glendenning <lglendenning@lnxi.com>
10 *
11 * Eric Biederman, of course, was a major help in this effort.
12 */
13
14#include <linux/module.h>
15#include <linux/types.h>
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/slab.h>
19#include <asm/io.h>
20#include <linux/mtd/mtd.h>
21#include <linux/mtd/map.h>
22#include <linux/mtd/cfi.h>
23#include <linux/mtd/flashchip.h>
24#include <linux/pci.h>
25#include <linux/pci_ids.h>
26#include <linux/list.h>
27
28#define MOD_NAME KBUILD_BASENAME
29
30#define ADDRESS_NAME_LEN 18
31
32#define ROM_PROBE_STEP_SIZE (64*1024) /* 64KiB */
33
34#define BIOS_CNTL 0xDC
35#define BIOS_LOCK_ENABLE 0x02
36#define BIOS_WRITE_ENABLE 0x01
37
38/* This became a 16-bit register, and EN2 has disappeared */
39#define FWH_DEC_EN1 0xD8
40#define FWH_F8_EN 0x8000
41#define FWH_F0_EN 0x4000
42#define FWH_E8_EN 0x2000
43#define FWH_E0_EN 0x1000
44#define FWH_D8_EN 0x0800
45#define FWH_D0_EN 0x0400
46#define FWH_C8_EN 0x0200
47#define FWH_C0_EN 0x0100
48#define FWH_LEGACY_F_EN 0x0080
49#define FWH_LEGACY_E_EN 0x0040
50/* reserved 0x0020 and 0x0010 */
51#define FWH_70_EN 0x0008
52#define FWH_60_EN 0x0004
53#define FWH_50_EN 0x0002
54#define FWH_40_EN 0x0001
55
56/* these are 32-bit values */
57#define FWH_SEL1 0xD0
58#define FWH_SEL2 0xD4
59
60#define FWH_8MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
61 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
62 FWH_70_EN | FWH_60_EN | FWH_50_EN | FWH_40_EN)
63
64#define FWH_7MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
65 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
66 FWH_70_EN | FWH_60_EN | FWH_50_EN)
67
68#define FWH_6MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
69 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
70 FWH_70_EN | FWH_60_EN)
71
72#define FWH_5MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
73 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN | \
74 FWH_70_EN)
75
76#define FWH_4MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
77 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN | FWH_C0_EN)
78
79#define FWH_3_5MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
80 FWH_D8_EN | FWH_D0_EN | FWH_C8_EN)
81
82#define FWH_3MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
83 FWH_D8_EN | FWH_D0_EN)
84
85#define FWH_2_5MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN | \
86 FWH_D8_EN)
87
88#define FWH_2MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN | FWH_E0_EN)
89
90#define FWH_1_5MiB (FWH_F8_EN | FWH_F0_EN | FWH_E8_EN)
91
92#define FWH_1MiB (FWH_F8_EN | FWH_F0_EN)
93
94#define FWH_0_5MiB (FWH_F8_EN)
95
96
97struct esb2rom_window {
98 void __iomem* virt;
99 unsigned long phys;
100 unsigned long size;
101 struct list_head maps;
102 struct resource rsrc;
103 struct pci_dev *pdev;
104};
105
106struct esb2rom_map_info {
107 struct list_head list;
108 struct map_info map;
109 struct mtd_info *mtd;
110 struct resource rsrc;
111 char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
112};
113
114static struct esb2rom_window esb2rom_window = {
115 .maps = LIST_HEAD_INIT(esb2rom_window.maps),
116};
117
118static void esb2rom_cleanup(struct esb2rom_window *window)
119{
120 struct esb2rom_map_info *map, *scratch;
121 u8 byte;
122
123 /* Disable writes through the rom window */
124 pci_read_config_byte(dev: window->pdev, BIOS_CNTL, val: &byte);
125 pci_write_config_byte(dev: window->pdev, BIOS_CNTL,
126 val: byte & ~BIOS_WRITE_ENABLE);
127
128 /* Free all of the mtd devices */
129 list_for_each_entry_safe(map, scratch, &window->maps, list) {
130 if (map->rsrc.parent)
131 release_resource(new: &map->rsrc);
132 mtd_device_unregister(master: map->mtd);
133 map_destroy(mtd: map->mtd);
134 list_del(entry: &map->list);
135 kfree(objp: map);
136 }
137 if (window->rsrc.parent)
138 release_resource(new: &window->rsrc);
139 if (window->virt) {
140 iounmap(addr: window->virt);
141 window->virt = NULL;
142 window->phys = 0;
143 window->size = 0;
144 }
145 pci_dev_put(dev: window->pdev);
146}
147
148static int __init esb2rom_init_one(struct pci_dev *pdev,
149 const struct pci_device_id *ent)
150{
151 static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
152 struct esb2rom_window *window = &esb2rom_window;
153 struct esb2rom_map_info *map = NULL;
154 unsigned long map_top;
155 u8 byte;
156 u16 word;
157
158 /* For now I just handle the ecb2 and I assume there
159 * are not a lot of resources up at the top of the address
160 * space. It is possible to handle other devices in the
161 * top 16MiB but it is very painful. Also since
162 * you can only really attach a FWH to an ICHX there
163 * a number of simplifications you can make.
164 *
165 * Also you can page firmware hubs if an 8MiB window isn't enough
166 * but don't currently handle that case either.
167 */
168 window->pdev = pci_dev_get(dev: pdev);
169
170 /* RLG: experiment 2. Force the window registers to the widest values */
171
172/*
173 pci_read_config_word(pdev, FWH_DEC_EN1, &word);
174 printk(KERN_DEBUG "Original FWH_DEC_EN1 : %x\n", word);
175 pci_write_config_byte(pdev, FWH_DEC_EN1, 0xff);
176 pci_read_config_byte(pdev, FWH_DEC_EN1, &byte);
177 printk(KERN_DEBUG "New FWH_DEC_EN1 : %x\n", byte);
178
179 pci_read_config_byte(pdev, FWH_DEC_EN2, &byte);
180 printk(KERN_DEBUG "Original FWH_DEC_EN2 : %x\n", byte);
181 pci_write_config_byte(pdev, FWH_DEC_EN2, 0x0f);
182 pci_read_config_byte(pdev, FWH_DEC_EN2, &byte);
183 printk(KERN_DEBUG "New FWH_DEC_EN2 : %x\n", byte);
184*/
185
186 /* Find a region continuous to the end of the ROM window */
187 window->phys = 0;
188 pci_read_config_word(dev: pdev, FWH_DEC_EN1, val: &word);
189 printk(KERN_DEBUG "pci_read_config_word : %x\n", word);
190
191 if ((word & FWH_8MiB) == FWH_8MiB)
192 window->phys = 0xff400000;
193 else if ((word & FWH_7MiB) == FWH_7MiB)
194 window->phys = 0xff500000;
195 else if ((word & FWH_6MiB) == FWH_6MiB)
196 window->phys = 0xff600000;
197 else if ((word & FWH_5MiB) == FWH_5MiB)
198 window->phys = 0xFF700000;
199 else if ((word & FWH_4MiB) == FWH_4MiB)
200 window->phys = 0xffc00000;
201 else if ((word & FWH_3_5MiB) == FWH_3_5MiB)
202 window->phys = 0xffc80000;
203 else if ((word & FWH_3MiB) == FWH_3MiB)
204 window->phys = 0xffd00000;
205 else if ((word & FWH_2_5MiB) == FWH_2_5MiB)
206 window->phys = 0xffd80000;
207 else if ((word & FWH_2MiB) == FWH_2MiB)
208 window->phys = 0xffe00000;
209 else if ((word & FWH_1_5MiB) == FWH_1_5MiB)
210 window->phys = 0xffe80000;
211 else if ((word & FWH_1MiB) == FWH_1MiB)
212 window->phys = 0xfff00000;
213 else if ((word & FWH_0_5MiB) == FWH_0_5MiB)
214 window->phys = 0xfff80000;
215
216 if (window->phys == 0) {
217 printk(KERN_ERR MOD_NAME ": Rom window is closed\n");
218 goto out;
219 }
220
221 /* reserved 0x0020 and 0x0010 */
222 window->phys -= 0x400000UL;
223 window->size = (0xffffffffUL - window->phys) + 1UL;
224
225 /* Enable writes through the rom window */
226 pci_read_config_byte(dev: pdev, BIOS_CNTL, val: &byte);
227 if (!(byte & BIOS_WRITE_ENABLE) && (byte & (BIOS_LOCK_ENABLE))) {
228 /* The BIOS will generate an error if I enable
229 * this device, so don't even try.
230 */
231 printk(KERN_ERR MOD_NAME ": firmware access control, I can't enable writes\n");
232 goto out;
233 }
234 pci_write_config_byte(dev: pdev, BIOS_CNTL, val: byte | BIOS_WRITE_ENABLE);
235
236 /*
237 * Try to reserve the window mem region. If this fails then
238 * it is likely due to the window being "reserved" by the BIOS.
239 */
240 window->rsrc.name = MOD_NAME;
241 window->rsrc.start = window->phys;
242 window->rsrc.end = window->phys + window->size - 1;
243 window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
244 if (request_resource(root: &iomem_resource, new: &window->rsrc)) {
245 window->rsrc.parent = NULL;
246 printk(KERN_DEBUG MOD_NAME ": "
247 "%s(): Unable to register resource %pR - kernel bug?\n",
248 __func__, &window->rsrc);
249 }
250
251 /* Map the firmware hub into my address space. */
252 window->virt = ioremap(offset: window->phys, size: window->size);
253 if (!window->virt) {
254 printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
255 window->phys, window->size);
256 goto out;
257 }
258
259 /* Get the first address to look for an rom chip at */
260 map_top = window->phys;
261 if ((window->phys & 0x3fffff) != 0) {
262 /* if not aligned on 4MiB, look 4MiB lower in address space */
263 map_top = window->phys + 0x400000;
264 }
265#if 1
266 /* The probe sequence run over the firmware hub lock
267 * registers sets them to 0x7 (no access).
268 * (Insane hardware design, but most copied Intel's.)
269 * ==> Probe at most the last 4M of the address space.
270 */
271 if (map_top < 0xffc00000)
272 map_top = 0xffc00000;
273#endif
274 /* Loop through and look for rom chips */
275 while ((map_top - 1) < 0xffffffffUL) {
276 struct cfi_private *cfi;
277 unsigned long offset;
278 int i;
279
280 if (!map) {
281 map = kmalloc(size: sizeof(*map), GFP_KERNEL);
282 if (!map)
283 goto out;
284 }
285 memset(map, 0, sizeof(*map));
286 INIT_LIST_HEAD(list: &map->list);
287 map->map.name = map->map_name;
288 map->map.phys = map_top;
289 offset = map_top - window->phys;
290 map->map.virt = (void __iomem *)
291 (((unsigned long)(window->virt)) + offset);
292 map->map.size = 0xffffffffUL - map_top + 1UL;
293 /* Set the name of the map to the address I am trying */
294 sprintf(buf: map->map_name, fmt: "%s @%08Lx",
295 MOD_NAME, (unsigned long long)map->map.phys);
296
297 /* Firmware hubs only use vpp when being programmed
298 * in a factory setting. So in-place programming
299 * needs to use a different method.
300 */
301 for(map->map.bankwidth = 32; map->map.bankwidth;
302 map->map.bankwidth >>= 1) {
303 char **probe_type;
304 /* Skip bankwidths that are not supported */
305 if (!map_bankwidth_supported(w: map->map.bankwidth))
306 continue;
307
308 /* Setup the map methods */
309 simple_map_init(&map->map);
310
311 /* Try all of the probe methods */
312 probe_type = rom_probe_types;
313 for(; *probe_type; probe_type++) {
314 map->mtd = do_map_probe(name: *probe_type, map: &map->map);
315 if (map->mtd)
316 goto found;
317 }
318 }
319 map_top += ROM_PROBE_STEP_SIZE;
320 continue;
321 found:
322 /* Trim the size if we are larger than the map */
323 if (map->mtd->size > map->map.size) {
324 printk(KERN_WARNING MOD_NAME
325 " rom(%llu) larger than window(%lu). fixing...\n",
326 (unsigned long long)map->mtd->size, map->map.size);
327 map->mtd->size = map->map.size;
328 }
329 if (window->rsrc.parent) {
330 /*
331 * Registering the MTD device in iomem may not be possible
332 * if there is a BIOS "reserved" and BUSY range. If this
333 * fails then continue anyway.
334 */
335 map->rsrc.name = map->map_name;
336 map->rsrc.start = map->map.phys;
337 map->rsrc.end = map->map.phys + map->mtd->size - 1;
338 map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
339 if (request_resource(root: &window->rsrc, new: &map->rsrc)) {
340 printk(KERN_ERR MOD_NAME
341 ": cannot reserve MTD resource\n");
342 map->rsrc.parent = NULL;
343 }
344 }
345
346 /* Make the whole region visible in the map */
347 map->map.virt = window->virt;
348 map->map.phys = window->phys;
349 cfi = map->map.fldrv_priv;
350 for(i = 0; i < cfi->numchips; i++)
351 cfi->chips[i].start += offset;
352
353 /* Now that the mtd devices is complete claim and export it */
354 map->mtd->owner = THIS_MODULE;
355 if (mtd_device_register(map->mtd, NULL, 0)) {
356 map_destroy(mtd: map->mtd);
357 map->mtd = NULL;
358 goto out;
359 }
360
361 /* Calculate the new value of map_top */
362 map_top += map->mtd->size;
363
364 /* File away the map structure */
365 list_add(new: &map->list, head: &window->maps);
366 map = NULL;
367 }
368
369 out:
370 /* Free any left over map structures */
371 kfree(objp: map);
372
373 /* See if I have any map structures */
374 if (list_empty(head: &window->maps)) {
375 esb2rom_cleanup(window);
376 return -ENODEV;
377 }
378 return 0;
379}
380
381static void esb2rom_remove_one(struct pci_dev *pdev)
382{
383 struct esb2rom_window *window = &esb2rom_window;
384 esb2rom_cleanup(window);
385}
386
387static const struct pci_device_id esb2rom_pci_tbl[] = {
388 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0,
389 PCI_ANY_ID, PCI_ANY_ID, },
390 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0,
391 PCI_ANY_ID, PCI_ANY_ID, },
392 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
393 PCI_ANY_ID, PCI_ANY_ID, },
394 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,
395 PCI_ANY_ID, PCI_ANY_ID, },
396 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1,
397 PCI_ANY_ID, PCI_ANY_ID, },
398 { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_0,
399 PCI_ANY_ID, PCI_ANY_ID, },
400 { 0, },
401};
402
403#if 0
404MODULE_DEVICE_TABLE(pci, esb2rom_pci_tbl);
405
406static struct pci_driver esb2rom_driver = {
407 .name = MOD_NAME,
408 .id_table = esb2rom_pci_tbl,
409 .probe = esb2rom_init_one,
410 .remove = esb2rom_remove_one,
411};
412#endif
413
414static int __init init_esb2rom(void)
415{
416 struct pci_dev *pdev;
417 const struct pci_device_id *id;
418 int retVal;
419
420 pdev = NULL;
421 for (id = esb2rom_pci_tbl; id->vendor; id++) {
422 printk(KERN_DEBUG "device id = %x\n", id->device);
423 pdev = pci_get_device(vendor: id->vendor, device: id->device, NULL);
424 if (pdev) {
425 printk(KERN_DEBUG "matched device = %x\n", id->device);
426 break;
427 }
428 }
429 if (pdev) {
430 printk(KERN_DEBUG "matched device id %x\n", id->device);
431 retVal = esb2rom_init_one(pdev, ent: &esb2rom_pci_tbl[0]);
432 pci_dev_put(dev: pdev);
433 printk(KERN_DEBUG "retVal = %d\n", retVal);
434 return retVal;
435 }
436 return -ENXIO;
437#if 0
438 return pci_register_driver(&esb2rom_driver);
439#endif
440}
441
442static void __exit cleanup_esb2rom(void)
443{
444 esb2rom_remove_one(pdev: esb2rom_window.pdev);
445}
446
447module_init(init_esb2rom);
448module_exit(cleanup_esb2rom);
449
450MODULE_LICENSE("GPL");
451MODULE_AUTHOR("Lew Glendenning <lglendenning@lnxi.com>");
452MODULE_DESCRIPTION("MTD map driver for BIOS chips on the ESB2 southbridge");
453

source code of linux/drivers/mtd/maps/esb2rom.c