1 /* $NetBSD: drm_memory.c,v 1.13 2018/08/27 15:32:06 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 1.13 2018/08/27 15:32:06 riastradh Exp $"); 34 35 #if defined(__i386__) || defined(__x86_64__) 36 37 # ifdef _KERNEL_OPT 38 # include "agp.h" 39 # if NAGP > 0 40 # include "agp_i810.h" 41 # else 42 # define NAGP_I810 0 43 # endif 44 # include "genfb.h" 45 # else 46 # define NAGP_I810 1 47 # define NGENFB 0 48 # endif 49 50 #else 51 52 # ifdef _KERNEL_OPT 53 # define NAGP_I810 0 54 # include "genfb.h" 55 # else 56 # define NAGP_I810 0 57 # define NGENFB 0 58 # endif 59 60 #endif 61 62 #include <sys/bus.h> 63 64 #if NAGP_I810 > 0 65 /* XXX include order botch -- shouldn't need to include pcivar.h */ 66 #include <dev/pci/pcivar.h> 67 #include <dev/pci/agpvar.h> 68 #endif 69 70 #if NGENFB > 0 71 #include <dev/wsfb/genfbvar.h> 72 #endif 73 74 #include <drm/drmP.h> 75 #include <drm/drm_legacy.h> 76 77 /* 78 * XXX drm_bus_borrow is a horrible kludge! 79 */ 80 static bool 81 drm_bus_borrow(bus_addr_t base, bus_size_t size, bus_space_handle_t *handlep) 82 { 83 84 #if NAGP_I810 > 0 85 if (agp_i810_borrow(base, size, handlep)) 86 return true; 87 #endif 88 89 #if NGENFB > 0 90 if (genfb_borrow(base, handlep)) 91 return true; 92 #endif 93 94 return false; 95 } 96 97 void 98 drm_legacy_ioremap(struct drm_local_map *map, struct drm_device *dev) 99 { 100 const bus_space_tag_t bst = dev->bst; 101 unsigned int unit; 102 103 /* 104 * Search dev's bus maps for a match. 105 */ 106 for (unit = 0; unit < dev->bus_nmaps; unit++) { 107 struct drm_bus_map *const bm = &dev->bus_maps[unit]; 108 int flags = bm->bm_flags; 109 110 /* Reject maps starting after the request. */ 111 if (map->offset < bm->bm_base) 112 continue; 113 114 /* Reject maps smaller than the request. */ 115 if (bm->bm_size < map->size) 116 continue; 117 118 /* Reject maps that the request doesn't fit in. */ 119 if ((bm->bm_size - map->size) < 120 (map->offset - bm->bm_base)) 121 continue; 122 123 /* Ensure we can map the space into virtual memory. */ 124 if (!ISSET(flags, BUS_SPACE_MAP_LINEAR)) 125 continue; 126 127 /* Reflect requested flags in the bus_space map. */ 128 if (ISSET(map->flags, _DRM_WRITE_COMBINING)) 129 flags |= BUS_SPACE_MAP_PREFETCHABLE; 130 131 /* Map it. */ 132 if (bus_space_map(bst, map->offset, map->size, flags, 133 &map->lm_data.bus_space.bsh)) 134 break; 135 136 map->lm_data.bus_space.bus_map = bm; 137 goto win; 138 } 139 140 /* Couldn't map it. Try borrowing from someone else. */ 141 if (drm_bus_borrow(map->offset, map->size, 142 &map->lm_data.bus_space.bsh)) { 143 map->lm_data.bus_space.bus_map = NULL; 144 goto win; 145 } 146 147 /* Failure! */ 148 return; 149 150 win: map->lm_data.bus_space.bst = bst; 151 map->handle = bus_space_vaddr(bst, map->lm_data.bus_space.bsh); 152 } 153 154 void 155 drm_legacy_ioremapfree(struct drm_local_map *map, struct drm_device *dev) 156 { 157 if (map->lm_data.bus_space.bus_map != NULL) { 158 bus_space_unmap(map->lm_data.bus_space.bst, 159 map->lm_data.bus_space.bsh, map->size); 160 map->lm_data.bus_space.bus_map = NULL; 161 map->handle = NULL; 162 } 163 } 164 165 /* 166 * Allocate a drm dma handle, allocate memory fit for DMA, and map it. 167 * 168 * XXX This is called drm_pci_alloc for hysterical raisins; it is not 169 * specific to PCI. 170 * 171 * XXX For now, we use non-blocking allocations because this is called 172 * by ioctls with the drm global mutex held. 173 * 174 * XXX Error information is lost because this returns NULL on failure, 175 * not even an error embedded in a pointer. 176 */ 177 struct drm_dma_handle * 178 drm_pci_alloc(struct drm_device *dev, size_t size, size_t align) 179 { 180 int nsegs; 181 int error; 182 183 /* 184 * Allocate a drm_dma_handle record. 185 */ 186 struct drm_dma_handle *const dmah = kmem_alloc(sizeof(*dmah), 187 KM_NOSLEEP); 188 if (dmah == NULL) { 189 error = -ENOMEM; 190 goto out; 191 } 192 dmah->dmah_tag = dev->dmat; 193 194 /* 195 * Allocate the requested amount of DMA-safe memory. 196 */ 197 /* XXX errno NetBSD->Linux */ 198 error = -bus_dmamem_alloc(dmah->dmah_tag, size, align, 0, 199 &dmah->dmah_seg, 1, &nsegs, BUS_DMA_NOWAIT); 200 if (error) 201 goto fail0; 202 KASSERT(nsegs == 1); 203 204 /* 205 * Map the DMA-safe memory into kernel virtual address space. 206 */ 207 /* XXX errno NetBSD->Linux */ 208 error = -bus_dmamem_map(dmah->dmah_tag, &dmah->dmah_seg, 1, size, 209 &dmah->vaddr, 210 (BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)); 211 if (error) 212 goto fail1; 213 dmah->size = size; 214 215 /* 216 * Create a map for DMA transfers. 217 */ 218 /* XXX errno NetBSD->Linux */ 219 error = -bus_dmamap_create(dmah->dmah_tag, size, 1, size, 0, 220 BUS_DMA_NOWAIT, &dmah->dmah_map); 221 if (error) 222 goto fail2; 223 224 /* 225 * Load the kva buffer into the map for DMA transfers. 226 */ 227 /* XXX errno NetBSD->Linux */ 228 error = -bus_dmamap_load(dmah->dmah_tag, dmah->dmah_map, dmah->vaddr, 229 size, NULL, (BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)); 230 if (error) 231 goto fail3; 232 233 /* Record the bus address for convenient reference. */ 234 dmah->busaddr = dmah->dmah_map->dm_segs[0].ds_addr; 235 236 /* Zero the DMA buffer. XXX Yikes! Is this necessary? */ 237 memset(dmah->vaddr, 0, size); 238 239 /* Success! */ 240 return dmah; 241 242 fail3: bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 243 fail2: bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 244 fail1: bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 245 fail0: dmah->dmah_tag = NULL; /* XXX paranoia */ 246 kmem_free(dmah, sizeof(*dmah)); 247 out: DRM_DEBUG("drm_pci_alloc failed: %d\n", error); 248 return NULL; 249 } 250 251 /* 252 * Release the bus DMA mappings and memory in dmah, and deallocate it. 253 */ 254 void 255 drm_pci_free(struct drm_device *dev, struct drm_dma_handle *dmah) 256 { 257 258 bus_dmamap_unload(dmah->dmah_tag, dmah->dmah_map); 259 bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 260 bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 261 bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 262 dmah->dmah_tag = NULL; /* XXX paranoia */ 263 kmem_free(dmah, sizeof(*dmah)); 264 } 265 266 /* 267 * Make sure the DMA-safe memory allocated for dev lies between 268 * min_addr and max_addr. Can be used multiple times to restrict the 269 * bounds further, but never to expand the bounds again. 270 * 271 * XXX Caller must guarantee nobody has used the tag yet, 272 * i.e. allocated any DMA memory. 273 */ 274 int 275 drm_limit_dma_space(struct drm_device *dev, resource_size_t min_addr, 276 resource_size_t max_addr) 277 { 278 int ret; 279 280 KASSERT(min_addr <= max_addr); 281 282 /* 283 * Limit it further if we have already limited it, and destroy 284 * the old subregion DMA tag. 285 */ 286 if (dev->dmat_subregion_p) { 287 min_addr = MAX(min_addr, dev->dmat_subregion_min); 288 max_addr = MIN(max_addr, dev->dmat_subregion_max); 289 bus_dmatag_destroy(dev->dmat); 290 } 291 292 /* 293 * If our limit contains the 32-bit space but for some reason 294 * we can't use a subregion, either because the bus doesn't 295 * support >32-bit DMA or because bus_dma(9) on this platform 296 * lacks bus_dmatag_subregion, just use the 32-bit space. 297 */ 298 if (min_addr == 0 && max_addr >= UINT32_C(0xffffffff) && 299 dev->bus_dmat == dev->bus_dmat32) { 300 dma32: dev->dmat = dev->bus_dmat32; 301 dev->dmat_subregion_p = false; 302 dev->dmat_subregion_min = 0; 303 dev->dmat_subregion_max = UINT32_C(0xffffffff); 304 return 0; 305 } 306 307 /* 308 * Create a DMA tag for a subregion from the bus's DMA tag. If 309 * that fails, restore dev->dmat to the whole region so that we 310 * need not worry about dev->dmat being uninitialized (not that 311 * the caller should try to allocate DMA-safe memory on failure 312 * anyway, but...paranoia). 313 */ 314 /* XXX errno NetBSD->Linux */ 315 ret = -bus_dmatag_subregion(dev->bus_dmat, min_addr, max_addr, 316 &dev->dmat, BUS_DMA_WAITOK); 317 if (ret) { 318 /* 319 * bus_dmatag_subregion may fail. If so, and if the 320 * subregion contains the 32-bit space, just use the 321 * 32-bit DMA tag. 322 */ 323 if (ret == -EOPNOTSUPP && dev->bus_dmat32 && 324 min_addr == 0 && max_addr >= UINT32_C(0xffffffff)) 325 goto dma32; 326 /* XXX Back out? */ 327 dev->dmat = dev->bus_dmat; 328 dev->dmat_subregion_p = false; 329 dev->dmat_subregion_min = 0; 330 dev->dmat_subregion_max = __type_max(bus_addr_t); 331 return ret; 332 } 333 334 /* 335 * Remember that we have a subregion tag so that we know to 336 * destroy it later, and record the bounds in case we need to 337 * limit them again. 338 */ 339 dev->dmat_subregion_p = true; 340 dev->dmat_subregion_min = min_addr; 341 dev->dmat_subregion_max = max_addr; 342 343 /* Success! */ 344 return 0; 345 } 346