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ck804xrom.c
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1 /*
2  * ck804xrom.c
3  *
4  * Normal mappings of chips in physical memory
5  *
6  * Dave Olsen <[email protected]>
7  * Ryan Jackson <[email protected]>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <asm/io.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/map.h>
18 #include <linux/mtd/cfi.h>
19 #include <linux/mtd/flashchip.h>
20 #include <linux/pci.h>
21 #include <linux/pci_ids.h>
22 #include <linux/list.h>
23 
24 
25 #define MOD_NAME KBUILD_BASENAME
26 
27 #define ADDRESS_NAME_LEN 18
28 
29 #define ROM_PROBE_STEP_SIZE (64*1024)
30 
31 #define DEV_CK804 1
32 #define DEV_MCP55 2
33 
35  void __iomem *virt;
36  unsigned long phys;
37  unsigned long size;
38  struct list_head maps;
39  struct resource rsrc;
40  struct pci_dev *pdev;
41 };
42 
44  struct list_head list;
45  struct map_info map;
46  struct mtd_info *mtd;
47  struct resource rsrc;
48  char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
49 };
50 
51 /*
52  * The following applies to ck804 only:
53  * The 2 bits controlling the window size are often set to allow reading
54  * the BIOS, but too small to allow writing, since the lock registers are
55  * 4MiB lower in the address space than the data.
56  *
57  * This is intended to prevent flashing the bios, perhaps accidentally.
58  *
59  * This parameter allows the normal driver to override the BIOS settings.
60  *
61  * The bits are 6 and 7. If both bits are set, it is a 5MiB window.
62  * If only the 7 Bit is set, it is a 4MiB window. Otherwise, a
63  * 64KiB window.
64  *
65  * The following applies to mcp55 only:
66  * The 15 bits controlling the window size are distributed as follows:
67  * byte @0x88: bit 0..7
68  * byte @0x8c: bit 8..15
69  * word @0x90: bit 16..30
70  * If all bits are enabled, we have a 16? MiB window
71  * Please set win_size_bits to 0x7fffffff if you actually want to do something
72  */
73 static uint win_size_bits = 0;
74 module_param(win_size_bits, uint, 0);
75 MODULE_PARM_DESC(win_size_bits, "ROM window size bits override, normally set by BIOS.");
76 
77 static struct ck804xrom_window ck804xrom_window = {
78  .maps = LIST_HEAD_INIT(ck804xrom_window.maps),
79 };
80 
81 static void ck804xrom_cleanup(struct ck804xrom_window *window)
82 {
83  struct ck804xrom_map_info *map, *scratch;
84  u8 byte;
85 
86  if (window->pdev) {
87  /* Disable writes through the rom window */
88  pci_read_config_byte(window->pdev, 0x6d, &byte);
89  pci_write_config_byte(window->pdev, 0x6d, byte & ~1);
90  }
91 
92  /* Free all of the mtd devices */
93  list_for_each_entry_safe(map, scratch, &window->maps, list) {
94  if (map->rsrc.parent)
95  release_resource(&map->rsrc);
96 
98  map_destroy(map->mtd);
99  list_del(&map->list);
100  kfree(map);
101  }
102  if (window->rsrc.parent)
103  release_resource(&window->rsrc);
104 
105  if (window->virt) {
106  iounmap(window->virt);
107  window->virt = NULL;
108  window->phys = 0;
109  window->size = 0;
110  }
111  pci_dev_put(window->pdev);
112 }
113 
114 
115 static int __devinit ck804xrom_init_one (struct pci_dev *pdev,
116  const struct pci_device_id *ent)
117 {
118  static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
119  u8 byte;
120  u16 word;
121  struct ck804xrom_window *window = &ck804xrom_window;
122  struct ck804xrom_map_info *map = NULL;
123  unsigned long map_top;
124 
125  /* Remember the pci dev I find the window in */
126  window->pdev = pci_dev_get(pdev);
127 
128  switch (ent->driver_data) {
129  case DEV_CK804:
130  /* Enable the selected rom window. This is often incorrectly
131  * set up by the BIOS, and the 4MiB offset for the lock registers
132  * requires the full 5MiB of window space.
133  *
134  * This 'write, then read' approach leaves the bits for
135  * other uses of the hardware info.
136  */
137  pci_read_config_byte(pdev, 0x88, &byte);
138  pci_write_config_byte(pdev, 0x88, byte | win_size_bits );
139 
140  /* Assume the rom window is properly setup, and find it's size */
141  pci_read_config_byte(pdev, 0x88, &byte);
142 
143  if ((byte & ((1<<7)|(1<<6))) == ((1<<7)|(1<<6)))
144  window->phys = 0xffb00000; /* 5MiB */
145  else if ((byte & (1<<7)) == (1<<7))
146  window->phys = 0xffc00000; /* 4MiB */
147  else
148  window->phys = 0xffff0000; /* 64KiB */
149  break;
150 
151  case DEV_MCP55:
152  pci_read_config_byte(pdev, 0x88, &byte);
153  pci_write_config_byte(pdev, 0x88, byte | (win_size_bits & 0xff));
154 
155  pci_read_config_byte(pdev, 0x8c, &byte);
156  pci_write_config_byte(pdev, 0x8c, byte | ((win_size_bits & 0xff00) >> 8));
157 
158  pci_read_config_word(pdev, 0x90, &word);
159  pci_write_config_word(pdev, 0x90, word | ((win_size_bits & 0x7fff0000) >> 16));
160 
161  window->phys = 0xff000000; /* 16MiB, hardcoded for now */
162  break;
163  }
164 
165  window->size = 0xffffffffUL - window->phys + 1UL;
166 
167  /*
168  * Try to reserve the window mem region. If this fails then
169  * it is likely due to a fragment of the window being
170  * "reserved" by the BIOS. In the case that the
171  * request_mem_region() fails then once the rom size is
172  * discovered we will try to reserve the unreserved fragment.
173  */
174  window->rsrc.name = MOD_NAME;
175  window->rsrc.start = window->phys;
176  window->rsrc.end = window->phys + window->size - 1;
177  window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
178  if (request_resource(&iomem_resource, &window->rsrc)) {
179  window->rsrc.parent = NULL;
181  " %s(): Unable to register resource %pR - kernel bug?\n",
182  __func__, &window->rsrc);
183  }
184 
185 
186  /* Enable writes through the rom window */
187  pci_read_config_byte(pdev, 0x6d, &byte);
188  pci_write_config_byte(pdev, 0x6d, byte | 1);
189 
190  /* FIXME handle registers 0x80 - 0x8C the bios region locks */
191 
192  /* For write accesses caches are useless */
193  window->virt = ioremap_nocache(window->phys, window->size);
194  if (!window->virt) {
195  printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
196  window->phys, window->size);
197  goto out;
198  }
199 
200  /* Get the first address to look for a rom chip at */
201  map_top = window->phys;
202 #if 1
203  /* The probe sequence run over the firmware hub lock
204  * registers sets them to 0x7 (no access).
205  * Probe at most the last 4MiB of the address space.
206  */
207  if (map_top < 0xffc00000)
208  map_top = 0xffc00000;
209 #endif
210  /* Loop through and look for rom chips. Since we don't know the
211  * starting address for each chip, probe every ROM_PROBE_STEP_SIZE
212  * bytes from the starting address of the window.
213  */
214  while((map_top - 1) < 0xffffffffUL) {
215  struct cfi_private *cfi;
216  unsigned long offset;
217  int i;
218 
219  if (!map)
220  map = kmalloc(sizeof(*map), GFP_KERNEL);
221 
222  if (!map) {
223  printk(KERN_ERR MOD_NAME ": kmalloc failed");
224  goto out;
225  }
226  memset(map, 0, sizeof(*map));
227  INIT_LIST_HEAD(&map->list);
228  map->map.name = map->map_name;
229  map->map.phys = map_top;
230  offset = map_top - window->phys;
231  map->map.virt = (void __iomem *)
232  (((unsigned long)(window->virt)) + offset);
233  map->map.size = 0xffffffffUL - map_top + 1UL;
234  /* Set the name of the map to the address I am trying */
235  sprintf(map->map_name, "%s @%08Lx",
236  MOD_NAME, (unsigned long long)map->map.phys);
237 
238  /* There is no generic VPP support */
239  for(map->map.bankwidth = 32; map->map.bankwidth;
240  map->map.bankwidth >>= 1)
241  {
242  char **probe_type;
243  /* Skip bankwidths that are not supported */
244  if (!map_bankwidth_supported(map->map.bankwidth))
245  continue;
246 
247  /* Setup the map methods */
248  simple_map_init(&map->map);
249 
250  /* Try all of the probe methods */
251  probe_type = rom_probe_types;
252  for(; *probe_type; probe_type++) {
253  map->mtd = do_map_probe(*probe_type, &map->map);
254  if (map->mtd)
255  goto found;
256  }
257  }
258  map_top += ROM_PROBE_STEP_SIZE;
259  continue;
260  found:
261  /* Trim the size if we are larger than the map */
262  if (map->mtd->size > map->map.size) {
264  " rom(%llu) larger than window(%lu). fixing...\n",
265  (unsigned long long)map->mtd->size, map->map.size);
266  map->mtd->size = map->map.size;
267  }
268  if (window->rsrc.parent) {
269  /*
270  * Registering the MTD device in iomem may not be possible
271  * if there is a BIOS "reserved" and BUSY range. If this
272  * fails then continue anyway.
273  */
274  map->rsrc.name = map->map_name;
275  map->rsrc.start = map->map.phys;
276  map->rsrc.end = map->map.phys + map->mtd->size - 1;
277  map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
278  if (request_resource(&window->rsrc, &map->rsrc)) {
280  ": cannot reserve MTD resource\n");
281  map->rsrc.parent = NULL;
282  }
283  }
284 
285  /* Make the whole region visible in the map */
286  map->map.virt = window->virt;
287  map->map.phys = window->phys;
288  cfi = map->map.fldrv_priv;
289  for(i = 0; i < cfi->numchips; i++)
290  cfi->chips[i].start += offset;
291 
292  /* Now that the mtd devices is complete claim and export it */
293  map->mtd->owner = THIS_MODULE;
294  if (mtd_device_register(map->mtd, NULL, 0)) {
295  map_destroy(map->mtd);
296  map->mtd = NULL;
297  goto out;
298  }
299 
300 
301  /* Calculate the new value of map_top */
302  map_top += map->mtd->size;
303 
304  /* File away the map structure */
305  list_add(&map->list, &window->maps);
306  map = NULL;
307  }
308 
309  out:
310  /* Free any left over map structures */
311  if (map)
312  kfree(map);
313 
314  /* See if I have any map structures */
315  if (list_empty(&window->maps)) {
316  ck804xrom_cleanup(window);
317  return -ENODEV;
318  }
319  return 0;
320 }
321 
322 
323 static void __devexit ck804xrom_remove_one (struct pci_dev *pdev)
324 {
325  struct ck804xrom_window *window = &ck804xrom_window;
326 
327  ck804xrom_cleanup(window);
328 }
329 
330 static struct pci_device_id ck804xrom_pci_tbl[] = {
331  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0051), .driver_data = DEV_CK804 },
332  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0360), .driver_data = DEV_MCP55 },
333  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0361), .driver_data = DEV_MCP55 },
334  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0362), .driver_data = DEV_MCP55 },
335  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0363), .driver_data = DEV_MCP55 },
336  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0364), .driver_data = DEV_MCP55 },
337  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0365), .driver_data = DEV_MCP55 },
338  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0366), .driver_data = DEV_MCP55 },
339  { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, 0x0367), .driver_data = DEV_MCP55 },
340  { 0, }
341 };
342 
343 #if 0
344 MODULE_DEVICE_TABLE(pci, ck804xrom_pci_tbl);
345 
346 static struct pci_driver ck804xrom_driver = {
347  .name = MOD_NAME,
348  .id_table = ck804xrom_pci_tbl,
349  .probe = ck804xrom_init_one,
350  .remove = ck804xrom_remove_one,
351 };
352 #endif
353 
354 static int __init init_ck804xrom(void)
355 {
356  struct pci_dev *pdev;
357  struct pci_device_id *id;
358  int retVal;
359  pdev = NULL;
360 
361  for(id = ck804xrom_pci_tbl; id->vendor; id++) {
362  pdev = pci_get_device(id->vendor, id->device, NULL);
363  if (pdev)
364  break;
365  }
366  if (pdev) {
367  retVal = ck804xrom_init_one(pdev, id);
368  pci_dev_put(pdev);
369  return retVal;
370  }
371  return -ENXIO;
372 #if 0
373  return pci_register_driver(&ck804xrom_driver);
374 #endif
375 }
376 
377 static void __exit cleanup_ck804xrom(void)
378 {
379  ck804xrom_remove_one(ck804xrom_window.pdev);
380 }
381 
382 module_init(init_ck804xrom);
383 module_exit(cleanup_ck804xrom);
384 
385 MODULE_LICENSE("GPL");
386 MODULE_AUTHOR("Eric Biederman <[email protected]>, Dave Olsen <[email protected]>");
387 MODULE_DESCRIPTION("MTD map driver for BIOS chips on the Nvidia ck804 southbridge");
388