drm_memory.c revision 1.7
1 /* $NetBSD: drm_memory.c,v 1.7 2015/04/29 04:38:55 riastradh Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Taylor R. Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: drm_memory.c,v 1.7 2015/04/29 04:38:55 riastradh Exp $"); 34 35 #ifdef _KERNEL_OPT 36 #include "agp_i810.h" 37 #include "genfb.h" 38 #else 39 #define NAGP_I810 1 /* XXX WTF? */ 40 #define NGENFB 0 /* XXX WTF? */ 41 #endif 42 43 #include <sys/bus.h> 44 45 #if NAGP_I810 > 0 46 /* XXX include order botch -- shouldn't need to include pcivar.h */ 47 #include <dev/pci/pcivar.h> 48 #include <dev/pci/agpvar.h> 49 #endif 50 51 #if NGENFB > 0 52 #include <dev/wsfb/genfbvar.h> 53 #endif 54 55 #include <drm/drmP.h> 56 57 /* 58 * XXX drm_bus_borrow is a horrible kludge! 59 */ 60 static bool 61 drm_bus_borrow(bus_addr_t base, bus_size_t size, bus_space_handle_t *handlep) 62 { 63 64 #if NAGP_I810 > 0 65 if (agp_i810_borrow(base, size, handlep)) 66 return true; 67 #endif 68 69 #if NGENFB > 0 70 if (genfb_borrow(base, handlep)) 71 return true; 72 #endif 73 74 return false; 75 } 76 77 void 78 drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev) 79 { 80 const bus_space_tag_t bst = dev->bst; 81 unsigned int unit; 82 83 /* 84 * Search dev's bus maps for a match. 85 */ 86 for (unit = 0; unit < dev->bus_nmaps; unit++) { 87 struct drm_bus_map *const bm = &dev->bus_maps[unit]; 88 int flags = bm->bm_flags; 89 90 /* Reject maps starting after the request. */ 91 if (map->offset < bm->bm_base) 92 continue; 93 94 /* Reject maps smaller than the request. */ 95 if (bm->bm_size < map->size) 96 continue; 97 98 /* Reject maps that the request doesn't fit in. */ 99 if ((bm->bm_size - map->size) < 100 (map->offset - bm->bm_base)) 101 continue; 102 103 /* Ensure we can map the space into virtual memory. */ 104 if (!ISSET(flags, BUS_SPACE_MAP_LINEAR)) 105 continue; 106 107 /* Reflect requested flags in the bus_space map. */ 108 if (ISSET(map->flags, _DRM_WRITE_COMBINING)) 109 flags |= BUS_SPACE_MAP_PREFETCHABLE; 110 111 /* Map it. */ 112 if (bus_space_map(bst, map->offset, map->size, flags, 113 &map->lm_data.bus_space.bsh)) 114 break; 115 116 map->lm_data.bus_space.bus_map = bm; 117 goto win; 118 } 119 120 /* Couldn't map it. Try borrowing from someone else. */ 121 if (drm_bus_borrow(map->offset, map->size, 122 &map->lm_data.bus_space.bsh)) { 123 map->lm_data.bus_space.bus_map = NULL; 124 goto win; 125 } 126 127 /* Failure! */ 128 return; 129 130 win: map->lm_data.bus_space.bst = bst; 131 map->handle = bus_space_vaddr(bst, map->lm_data.bus_space.bsh); 132 } 133 134 void 135 drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev) 136 { 137 if (map->lm_data.bus_space.bus_map != NULL) { 138 bus_space_unmap(map->lm_data.bus_space.bst, 139 map->lm_data.bus_space.bsh, map->size); 140 map->lm_data.bus_space.bus_map = NULL; 141 map->handle = NULL; 142 } 143 } 144 145 /* 146 * Allocate a drm dma handle, allocate memory fit for DMA, and map it. 147 * 148 * XXX This is called drm_pci_alloc for hysterical raisins; it is not 149 * specific to PCI. 150 * 151 * XXX For now, we use non-blocking allocations because this is called 152 * by ioctls with the drm global mutex held. 153 * 154 * XXX Error information is lost because this returns NULL on failure, 155 * not even an error embedded in a pointer. 156 */ 157 struct drm_dma_handle * 158 drm_pci_alloc(struct drm_device *dev, size_t size, size_t align) 159 { 160 int nsegs; 161 int error; 162 163 /* 164 * Allocate a drm_dma_handle record. 165 */ 166 struct drm_dma_handle *const dmah = kmem_alloc(sizeof(*dmah), 167 KM_NOSLEEP); 168 if (dmah == NULL) { 169 error = -ENOMEM; 170 goto out; 171 } 172 dmah->dmah_tag = dev->dmat; 173 174 /* 175 * Allocate the requested amount of DMA-safe memory. 176 */ 177 /* XXX errno NetBSD->Linux */ 178 error = -bus_dmamem_alloc(dmah->dmah_tag, size, align, 0, 179 &dmah->dmah_seg, 1, &nsegs, BUS_DMA_NOWAIT); 180 if (error) 181 goto fail0; 182 KASSERT(nsegs == 1); 183 184 /* 185 * Map the DMA-safe memory into kernel virtual address space. 186 */ 187 /* XXX errno NetBSD->Linux */ 188 error = -bus_dmamem_map(dmah->dmah_tag, &dmah->dmah_seg, 1, size, 189 &dmah->vaddr, 190 (BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)); 191 if (error) 192 goto fail1; 193 dmah->size = size; 194 195 /* 196 * Create a map for DMA transfers. 197 */ 198 /* XXX errno NetBSD->Linux */ 199 error = -bus_dmamap_create(dmah->dmah_tag, size, 1, size, 0, 200 BUS_DMA_NOWAIT, &dmah->dmah_map); 201 if (error) 202 goto fail2; 203 204 /* 205 * Load the kva buffer into the map for DMA transfers. 206 */ 207 /* XXX errno NetBSD->Linux */ 208 error = -bus_dmamap_load(dmah->dmah_tag, dmah->dmah_map, dmah->vaddr, 209 size, NULL, (BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)); 210 if (error) 211 goto fail3; 212 213 /* Record the bus address for convenient reference. */ 214 dmah->busaddr = dmah->dmah_map->dm_segs[0].ds_addr; 215 216 /* Zero the DMA buffer. XXX Yikes! Is this necessary? */ 217 memset(dmah->vaddr, 0, size); 218 219 /* Success! */ 220 return dmah; 221 222 fail3: bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 223 fail2: bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 224 fail1: bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 225 fail0: dmah->dmah_tag = NULL; /* XXX paranoia */ 226 kmem_free(dmah, sizeof(*dmah)); 227 out: DRM_DEBUG("drm_pci_alloc failed: %d\n", error); 228 return NULL; 229 } 230 231 /* 232 * Release the bus DMA mappings and memory in dmah, and deallocate it. 233 */ 234 void 235 drm_pci_free(struct drm_device *dev, struct drm_dma_handle *dmah) 236 { 237 238 bus_dmamap_unload(dmah->dmah_tag, dmah->dmah_map); 239 bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 240 bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 241 bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 242 dmah->dmah_tag = NULL; /* XXX paranoia */ 243 kmem_free(dmah, sizeof(*dmah)); 244 } 245 246 /* 247 * Make sure the DMA-safe memory allocated for dev lies between 248 * min_addr and max_addr. Can be used multiple times to restrict the 249 * bounds further, but never to expand the bounds again. 250 * 251 * XXX Caller must guarantee nobody has used the tag yet, 252 * i.e. allocated any DMA memory. 253 */ 254 int 255 drm_limit_dma_space(struct drm_device *dev, resource_size_t min_addr, 256 resource_size_t max_addr) 257 { 258 int ret; 259 260 KASSERT(min_addr <= max_addr); 261 262 /* 263 * Limit it further if we have already limited it, and destroy 264 * the old subregion DMA tag. 265 */ 266 if (dev->dmat_subregion_p) { 267 min_addr = MAX(min_addr, dev->dmat_subregion_min); 268 max_addr = MIN(max_addr, dev->dmat_subregion_max); 269 bus_dmatag_destroy(dev->dmat); 270 } 271 272 /* 273 * Create a DMA tag for a subregion from the bus's DMA tag. If 274 * that fails, restore dev->dmat to the whole region so that we 275 * need not worry about dev->dmat being uninitialized (not that 276 * the caller should try to allocate DMA-safe memory on failure 277 * anyway, but...paranoia). 278 */ 279 /* XXX errno NetBSD->Linux */ 280 ret = -bus_dmatag_subregion(dev->bus_dmat, min_addr, max_addr, 281 &dev->dmat, BUS_DMA_WAITOK); 282 if (ret) { 283 dev->dmat = dev->bus_dmat; 284 dev->dmat_subregion_p = false; 285 return ret; 286 } 287 288 /* 289 * Remember that we have a subregion tag so that we know to 290 * destroy it later, and record the bounds in case we need to 291 * limit them again. 292 */ 293 dev->dmat_subregion_p = true; 294 dev->dmat_subregion_min = min_addr; 295 dev->dmat_subregion_max = max_addr; 296 297 /* Success! */ 298 return 0; 299 } 300
Indexes created Tue Sep 30 20:09:53 GMT 2025