[PATCH] bfs iget() abuses
[linux-2.6] / drivers / char / agp / efficeon-agp.c
1 /*
2  * Transmeta's Efficeon AGPGART driver.
3  * 
4  * Based upon a diff by Linus around November '02.
5  *
6  * Ported to the 2.6 kernel by Carlos Puchol <cpglinux@puchol.com>
7  * and H. Peter Anvin <hpa@transmeta.com>.
8  */
9
10 /*
11  * NOTE-cpg-040217:
12  * 
13  *   - when compiled as a module, after loading the module,
14  *     it will refuse to unload, indicating it is in use,
15  *     when it is not.
16  *   - no s3 (suspend to ram) testing.
17  *   - tested on the efficeon integrated nothbridge for tens
18  *     of iterations of starting x and glxgears.
19  *   - tested with radeon 9000 and radeon mobility m9 cards
20  *   - tested with c3/c4 enabled (with the mobility m9 card)
21  */
22
23 #include <linux/module.h>
24 #include <linux/pci.h>
25 #include <linux/init.h>
26 #include <linux/agp_backend.h>
27 #include <linux/gfp.h>
28 #include <linux/page-flags.h>
29 #include <linux/mm.h>
30 #include "agp.h"
31
32 /*
33  * The real differences to the generic AGP code is
34  * in the GART mappings - a two-level setup with the
35  * first level being an on-chip 64-entry table.
36  *
37  * The page array is filled through the ATTPAGE register
38  * (Aperture Translation Table Page Register) at 0xB8. Bits:
39  *  31:20: physical page address
40  *   11:9: Page Attribute Table Index (PATI)
41  *         must match the PAT index for the
42  *         mapped pages (the 2nd level page table pages
43  *         themselves should be just regular WB-cacheable,
44  *         so this is normally zero.)
45  *      8: Present
46  *    7:6: reserved, write as zero
47  *    5:0: GATT directory index: which 1st-level entry
48  * 
49  * The Efficeon AGP spec requires pages to be WB-cacheable
50  * but to be explicitly CLFLUSH'd after any changes.
51  */
52 #define EFFICEON_ATTPAGE        0xb8
53 #define EFFICEON_L1_SIZE        64      /* Number of PDE pages */
54
55 #define EFFICEON_PATI           (0 << 9)
56 #define EFFICEON_PRESENT        (1 << 8)
57
58 static struct _efficeon_private {
59         unsigned long l1_table[EFFICEON_L1_SIZE];
60 } efficeon_private;
61
62 static struct gatt_mask efficeon_generic_masks[] =
63 {
64         {.mask = 0x00000001, .type = 0}
65 };
66
67 static struct aper_size_info_lvl2 efficeon_generic_sizes[4] =
68 {
69         {256, 65536, 0},
70         {128, 32768, 32},
71         {64, 16384, 48},
72         {32, 8192, 56}
73 };
74
75 /*
76  * Control interfaces are largely identical to
77  * the legacy Intel 440BX..
78  */
79
80 static int efficeon_fetch_size(void)
81 {
82         int i;
83         u16 temp;
84         struct aper_size_info_lvl2 *values;
85
86         pci_read_config_word(agp_bridge->dev, INTEL_APSIZE, &temp);
87         values = A_SIZE_LVL2(agp_bridge->driver->aperture_sizes);
88
89         for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {
90                 if (temp == values[i].size_value) {
91                         agp_bridge->previous_size =
92                             agp_bridge->current_size = (void *) (values + i);
93                         agp_bridge->aperture_size_idx = i;
94                         return values[i].size;
95                 }
96         }
97
98         return 0;
99 }
100
101 static void efficeon_tlbflush(struct agp_memory * mem)
102 {
103         printk(KERN_DEBUG PFX "efficeon_tlbflush()\n");
104         pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2200);
105         pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
106 }
107
108 static void efficeon_cleanup(void)
109 {
110         u16 temp;
111         struct aper_size_info_lvl2 *previous_size;
112
113         printk(KERN_DEBUG PFX "efficeon_cleanup()\n");
114         previous_size = A_SIZE_LVL2(agp_bridge->previous_size);
115         pci_read_config_word(agp_bridge->dev, INTEL_NBXCFG, &temp);
116         pci_write_config_word(agp_bridge->dev, INTEL_NBXCFG, temp & ~(1 << 9));
117         pci_write_config_word(agp_bridge->dev, INTEL_APSIZE,
118                               previous_size->size_value);
119 }
120
121 static int efficeon_configure(void)
122 {
123         u32 temp;
124         u16 temp2;
125         struct aper_size_info_lvl2 *current_size;
126
127         printk(KERN_DEBUG PFX "efficeon_configure()\n");
128         
129         current_size = A_SIZE_LVL2(agp_bridge->current_size);
130
131         /* aperture size */
132         pci_write_config_word(agp_bridge->dev, INTEL_APSIZE,
133                               current_size->size_value);
134
135         /* address to map to */
136         pci_read_config_dword(agp_bridge->dev, AGP_APBASE, &temp);
137         agp_bridge->gart_bus_addr = (temp & PCI_BASE_ADDRESS_MEM_MASK);
138
139         /* agpctrl */
140         pci_write_config_dword(agp_bridge->dev, INTEL_AGPCTRL, 0x2280);
141
142         /* paccfg/nbxcfg */
143         pci_read_config_word(agp_bridge->dev, INTEL_NBXCFG, &temp2);
144         pci_write_config_word(agp_bridge->dev, INTEL_NBXCFG,
145                               (temp2 & ~(1 << 10)) | (1 << 9) | (1 << 11));
146         /* clear any possible error conditions */
147         pci_write_config_byte(agp_bridge->dev, INTEL_ERRSTS + 1, 7);
148         return 0;
149 }
150
151 static int efficeon_free_gatt_table(struct agp_bridge_data *bridge)
152 {
153         int index, freed = 0;
154
155         for (index = 0; index < EFFICEON_L1_SIZE; index++) {
156                 unsigned long page = efficeon_private.l1_table[index];
157                 if (page) {
158                         efficeon_private.l1_table[index] = 0;
159                         ClearPageReserved(virt_to_page((char *)page));
160                         free_page(page);
161                         freed++;
162                 }
163                 printk(KERN_DEBUG PFX "efficeon_free_gatt_table(%p, %02x, %08x)\n",
164                         agp_bridge->dev, EFFICEON_ATTPAGE, index);
165                 pci_write_config_dword(agp_bridge->dev,
166                         EFFICEON_ATTPAGE, index);
167         }
168         printk(KERN_DEBUG PFX "efficeon_free_gatt_table() freed %d pages\n", freed);
169         return 0;
170 }
171
172
173 /*
174  * Since we don't need contigious memory we just try
175  * to get the gatt table once
176  */
177
178 #define GET_PAGE_DIR_OFF(addr) (addr >> 22)
179 #define GET_PAGE_DIR_IDX(addr) (GET_PAGE_DIR_OFF(addr) - \
180         GET_PAGE_DIR_OFF(agp_bridge->gart_bus_addr))
181 #define GET_GATT_OFF(addr) ((addr & 0x003ff000) >> 12)
182 #undef  GET_GATT
183 #define GET_GATT(addr) (efficeon_private.gatt_pages[\
184         GET_PAGE_DIR_IDX(addr)]->remapped)
185
186 static int efficeon_create_gatt_table(struct agp_bridge_data *bridge)
187 {
188         int index;
189         const int pati    = EFFICEON_PATI;
190         const int present = EFFICEON_PRESENT;
191         const int clflush_chunk = ((cpuid_ebx(1) >> 8) & 0xff) << 3;
192         int num_entries, l1_pages;
193         
194         num_entries = A_SIZE_LVL2(agp_bridge->current_size)->num_entries;
195
196         printk(KERN_DEBUG PFX "efficeon_create_gatt_table(%d)\n", num_entries);
197
198         /* There are 2^10 PTE pages per PDE page */
199         BUG_ON(num_entries & 0x3ff);
200         l1_pages = num_entries >> 10;
201
202         for (index = 0 ; index < l1_pages ; index++) {
203                 int offset;
204                 unsigned long page;
205                 unsigned long value;
206
207                 page = efficeon_private.l1_table[index];
208                 BUG_ON(page);
209
210                 page = get_zeroed_page(GFP_KERNEL);
211                 if (!page) {
212                         efficeon_free_gatt_table(agp_bridge);
213                         return -ENOMEM;
214                 }
215                 SetPageReserved(virt_to_page((char *)page));
216
217                 for (offset = 0; offset < PAGE_SIZE; offset += clflush_chunk)
218                         asm volatile("clflush %0" : : "m" (*(char *)(page+offset)));
219
220                 efficeon_private.l1_table[index] = page;
221
222                 value = virt_to_gart(page) | pati | present | index;
223
224                 pci_write_config_dword(agp_bridge->dev,
225                         EFFICEON_ATTPAGE, value);
226         }
227
228         return 0;
229 }
230
231 static int efficeon_insert_memory(struct agp_memory * mem, off_t pg_start, int type)
232 {
233         int i, count = mem->page_count, num_entries;
234         unsigned int *page, *last_page;
235         const int clflush_chunk = ((cpuid_ebx(1) >> 8) & 0xff) << 3;
236         const unsigned long clflush_mask = ~(clflush_chunk-1);
237
238         printk(KERN_DEBUG PFX "efficeon_insert_memory(%lx, %d)\n", pg_start, count);
239
240         num_entries = A_SIZE_LVL2(agp_bridge->current_size)->num_entries;
241         if ((pg_start + mem->page_count) > num_entries)
242                 return -EINVAL;
243         if (type != 0 || mem->type != 0)
244                 return -EINVAL;
245
246         if (mem->is_flushed == FALSE) {
247                 global_cache_flush();
248                 mem->is_flushed = TRUE;
249         }
250
251         last_page = NULL;
252         for (i = 0; i < count; i++) {
253                 int index = pg_start + i;
254                 unsigned long insert = mem->memory[i];
255
256                 page = (unsigned int *) efficeon_private.l1_table[index >> 10];
257
258                 if (!page)
259                         continue;
260                 
261                 page += (index & 0x3ff);
262                 *page = insert;
263
264                 /* clflush is slow, so don't clflush until we have to */
265                 if ( last_page && 
266                      ((unsigned long)page^(unsigned long)last_page) & clflush_mask )
267                     asm volatile("clflush %0" : : "m" (*last_page));
268
269                 last_page = page;
270         }
271
272         if ( last_page )
273                 asm volatile("clflush %0" : : "m" (*last_page));
274
275         agp_bridge->driver->tlb_flush(mem);
276         return 0;
277 }
278
279 static int efficeon_remove_memory(struct agp_memory * mem, off_t pg_start, int type)
280 {
281         int i, count = mem->page_count, num_entries;
282
283         printk(KERN_DEBUG PFX "efficeon_remove_memory(%lx, %d)\n", pg_start, count);
284
285         num_entries = A_SIZE_LVL2(agp_bridge->current_size)->num_entries;
286
287         if ((pg_start + mem->page_count) > num_entries)
288                 return -EINVAL;
289         if (type != 0 || mem->type != 0)
290                 return -EINVAL;
291
292         for (i = 0; i < count; i++) {
293                 int index = pg_start + i;
294                 unsigned int *page = (unsigned int *) efficeon_private.l1_table[index >> 10];
295
296                 if (!page)
297                         continue;
298                 page += (index & 0x3ff);
299                 *page = 0;
300         }
301         agp_bridge->driver->tlb_flush(mem);
302         return 0;
303 }
304
305
306 static struct agp_bridge_driver efficeon_driver = {
307         .owner                  = THIS_MODULE,
308         .aperture_sizes         = efficeon_generic_sizes,
309         .size_type              = LVL2_APER_SIZE,
310         .num_aperture_sizes     = 4,
311         .configure              = efficeon_configure,
312         .fetch_size             = efficeon_fetch_size,
313         .cleanup                = efficeon_cleanup,
314         .tlb_flush              = efficeon_tlbflush,
315         .mask_memory            = agp_generic_mask_memory,
316         .masks                  = efficeon_generic_masks,
317         .agp_enable             = agp_generic_enable,
318         .cache_flush            = global_cache_flush,
319
320         // Efficeon-specific GATT table setup / populate / teardown
321         .create_gatt_table      = efficeon_create_gatt_table,
322         .free_gatt_table        = efficeon_free_gatt_table,
323         .insert_memory          = efficeon_insert_memory,
324         .remove_memory          = efficeon_remove_memory,
325         .cant_use_aperture      = 0,    // 1 might be faster?
326
327         // Generic
328         .alloc_by_type          = agp_generic_alloc_by_type,
329         .free_by_type           = agp_generic_free_by_type,
330         .agp_alloc_page         = agp_generic_alloc_page,
331         .agp_destroy_page       = agp_generic_destroy_page,
332 };
333
334
335 static int agp_efficeon_resume(struct pci_dev *pdev)
336 {
337         printk(KERN_DEBUG PFX "agp_efficeon_resume()\n");
338         return efficeon_configure();
339 }
340
341 static int __devinit agp_efficeon_probe(struct pci_dev *pdev,
342                                      const struct pci_device_id *ent)
343 {
344         struct agp_bridge_data *bridge;
345         u8 cap_ptr;
346         struct resource *r;
347
348         cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
349         if (!cap_ptr)
350                 return -ENODEV;
351
352         /* Probe for Efficeon controller */
353         if (pdev->device != PCI_DEVICE_ID_EFFICEON) {
354                 printk(KERN_ERR PFX "Unsupported Efficeon chipset (device id: %04x)\n",
355                     pdev->device);
356                 return -ENODEV;
357         }
358
359         printk(KERN_INFO PFX "Detected Transmeta Efficeon TM8000 series chipset\n");
360
361         bridge = agp_alloc_bridge();
362         if (!bridge)
363                 return -ENOMEM;
364
365         bridge->driver = &efficeon_driver;
366         bridge->dev = pdev;
367         bridge->capndx = cap_ptr;
368
369         /*
370         * The following fixes the case where the BIOS has "forgotten" to
371         * provide an address range for the GART.
372         * 20030610 - hamish@zot.org
373         */
374         r = &pdev->resource[0];
375         if (!r->start && r->end) {
376                 if(pci_assign_resource(pdev, 0)) {
377                         printk(KERN_ERR PFX "could not assign resource 0\n");
378                         return -ENODEV;
379                 }
380         }
381
382         /*
383         * If the device has not been properly setup, the following will catch
384         * the problem and should stop the system from crashing.
385         * 20030610 - hamish@zot.org
386         */
387         if (pci_enable_device(pdev)) {
388                 printk(KERN_ERR PFX "Unable to Enable PCI device\n");
389                 return -ENODEV;
390         }
391
392         /* Fill in the mode register */
393         if (cap_ptr) {
394                 pci_read_config_dword(pdev,
395                                 bridge->capndx+PCI_AGP_STATUS,
396                                 &bridge->mode);
397         }
398
399         pci_set_drvdata(pdev, bridge);
400         return agp_add_bridge(bridge);
401 }
402
403 static void __devexit agp_efficeon_remove(struct pci_dev *pdev)
404 {
405         struct agp_bridge_data *bridge = pci_get_drvdata(pdev);
406
407         agp_remove_bridge(bridge);
408         agp_put_bridge(bridge);
409 }
410
411 static int agp_efficeon_suspend(struct pci_dev *dev, pm_message_t state)
412 {
413         return 0;
414 }
415
416
417 static struct pci_device_id agp_efficeon_pci_table[] = {
418         {
419         .class          = (PCI_CLASS_BRIDGE_HOST << 8),
420         .class_mask     = ~0,
421         .vendor         = PCI_VENDOR_ID_TRANSMETA,
422         .device         = PCI_ANY_ID,
423         .subvendor      = PCI_ANY_ID,
424         .subdevice      = PCI_ANY_ID,
425         },
426         { }
427 };
428
429 MODULE_DEVICE_TABLE(pci, agp_efficeon_pci_table);
430
431 static struct pci_driver agp_efficeon_pci_driver = {
432         .name           = "agpgart-efficeon",
433         .id_table       = agp_efficeon_pci_table,
434         .probe          = agp_efficeon_probe,
435         .remove         = agp_efficeon_remove,
436         .suspend        = agp_efficeon_suspend,
437         .resume         = agp_efficeon_resume,
438 };
439
440 static int __init agp_efficeon_init(void)
441 {
442         static int agp_initialised=0;
443
444         if (agp_off)
445                 return -EINVAL;
446
447         if (agp_initialised == 1)
448                 return 0;
449         agp_initialised=1;
450
451         return pci_register_driver(&agp_efficeon_pci_driver);
452 }
453
454 static void __exit agp_efficeon_cleanup(void)
455 {
456         pci_unregister_driver(&agp_efficeon_pci_driver);
457 }
458
459 module_init(agp_efficeon_init);
460 module_exit(agp_efficeon_cleanup);
461
462 MODULE_AUTHOR("Carlos Puchol <cpglinux@puchol.com>");
463 MODULE_LICENSE("GPL and additional rights");