1 /* $NetBSD: drm_memory.c,v 1.3 2014/05/14 04:38:49 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 1.3 2014/05/14 04:38:49 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_space_handle_t *handlep) 62 { 63 64 #if NAGP_I810 > 0 65 if (agp_i810_borrow(base, 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_ioremap(struct drm_device *dev, struct drm_local_map *map) 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 89 /* Reject maps starting after the request. */ 90 if (map->offset < bm->bm_base) 91 continue; 92 93 /* Reject maps smaller than the request. */ 94 if (bm->bm_size < map->size) 95 continue; 96 97 /* Reject maps that the request doesn't fit in. */ 98 if ((bm->bm_size - map->size) < 99 (map->offset - bm->bm_base)) 100 continue; 101 102 /* Ensure we can map the space into virtual memory. */ 103 if (!ISSET(bm->bm_flags, BUS_SPACE_MAP_LINEAR)) 104 continue; 105 106 /* Map it. */ 107 if (bus_space_map(bst, map->offset, map->size, 108 bm->bm_flags, &map->lm_data.bus_space.bsh)) 109 break; 110 111 map->lm_data.bus_space.bus_map = bm; 112 goto win; 113 } 114 115 /* Couldn't map it. Try borrowing from someone else. */ 116 if (drm_bus_borrow(map->offset, &map->lm_data.bus_space.bsh)) { 117 map->lm_data.bus_space.bus_map = NULL; 118 goto win; 119 } 120 121 /* Failure! */ 122 return NULL; 123 124 win: map->lm_data.bus_space.bst = bst; 125 return bus_space_vaddr(bst, map->lm_data.bus_space.bsh); 126 } 127 128 void 129 drm_iounmap(struct drm_device *dev, struct drm_local_map *map) 130 { 131 if (map->lm_data.bus_space.bus_map != NULL) { 132 bus_space_unmap(map->lm_data.bus_space.bst, 133 map->lm_data.bus_space.bsh, map->size); 134 map->lm_data.bus_space.bus_map = NULL; 135 } 136 } 137 138 /* 139 * Allocate a drm dma handle, allocate memory fit for DMA, and map it. 140 * 141 * XXX This is called drm_pci_alloc for hysterical raisins; it is not 142 * specific to PCI. 143 * 144 * XXX For now, we use non-blocking allocations because this is called 145 * by ioctls with the drm global mutex held. 146 * 147 * XXX Error information is lost because this returns NULL on failure, 148 * not even an error embedded in a pointer. 149 */ 150 struct drm_dma_handle * 151 drm_pci_alloc(struct drm_device *dev, size_t size, size_t align) 152 { 153 int nsegs; 154 int error; 155 156 /* 157 * Allocate a drm_dma_handle record. 158 */ 159 struct drm_dma_handle *const dmah = kmem_alloc(sizeof(*dmah), 160 KM_NOSLEEP); 161 if (dmah == NULL) { 162 error = -ENOMEM; 163 goto out; 164 } 165 dmah->dmah_tag = dev->dmat; 166 167 /* 168 * Allocate the requested amount of DMA-safe memory. 169 */ 170 /* XXX errno NetBSD->Linux */ 171 error = -bus_dmamem_alloc(dmah->dmah_tag, size, align, 0, 172 &dmah->dmah_seg, 1, &nsegs, BUS_DMA_NOWAIT); 173 if (error) 174 goto fail0; 175 KASSERT(nsegs == 1); 176 177 /* 178 * XXX Old drm passed BUS_DMA_NOWAIT below but BUS_DMA_WAITOK 179 * above. WTF? 180 */ 181 182 /* 183 * Map the DMA-safe memory into kernel virtual address space. 184 */ 185 /* XXX errno NetBSD->Linux */ 186 error = -bus_dmamem_map(dmah->dmah_tag, &dmah->dmah_seg, 1, size, 187 &dmah->vaddr, 188 (BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)); 189 if (error) 190 goto fail1; 191 dmah->size = size; 192 193 /* 194 * Create a map for DMA transfers. 195 */ 196 /* XXX errno NetBSD->Linux */ 197 error = -bus_dmamap_create(dmah->dmah_tag, size, 1, size, 0, 198 BUS_DMA_NOWAIT, &dmah->dmah_map); 199 if (error) 200 goto fail2; 201 202 /* 203 * Load the kva buffer into the map for DMA transfers. 204 */ 205 /* XXX errno NetBSD->Linux */ 206 error = -bus_dmamap_load(dmah->dmah_tag, dmah->dmah_map, dmah->vaddr, 207 size, NULL, (BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)); 208 if (error) 209 goto fail3; 210 211 /* Record the bus address for convenient reference. */ 212 dmah->busaddr = dmah->dmah_map->dm_segs[0].ds_addr; 213 214 /* Zero the DMA buffer. XXX Yikes! Is this necessary? */ 215 memset(dmah->vaddr, 0, size); 216 217 /* Success! */ 218 return dmah; 219 220 fail3: bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 221 fail2: bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 222 fail1: bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 223 fail0: dmah->dmah_tag = NULL; /* XXX paranoia */ 224 kmem_free(dmah, sizeof(*dmah)); 225 out: DRM_DEBUG("drm_pci_alloc failed: %d\n", error); 226 return NULL; 227 } 228 229 /* 230 * Release the bus DMA mappings and memory in dmah, and deallocate it. 231 */ 232 void 233 drm_pci_free(struct drm_device *dev, struct drm_dma_handle *dmah) 234 { 235 236 bus_dmamap_unload(dmah->dmah_tag, dmah->dmah_map); 237 bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 238 bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 239 bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 240 dmah->dmah_tag = NULL; /* XXX paranoia */ 241 kmem_free(dmah, sizeof(*dmah)); 242 } 243 244 /* 245 * Make sure the DMA-safe memory allocated for dev lies between 246 * min_addr and max_addr. Can be used multiple times to restrict the 247 * bounds further, but never to expand the bounds again. 248 * 249 * XXX Caller must guarantee nobody has used the tag yet, 250 * i.e. allocated any DMA memory. 251 */ 252 int 253 drm_limit_dma_space(struct drm_device *dev, resource_size_t min_addr, 254 resource_size_t max_addr) 255 { 256 int ret; 257 258 KASSERT(min_addr <= max_addr); 259 260 /* 261 * Limit it further if we have already limited it, and destroy 262 * the old subregion DMA tag. 263 */ 264 if (dev->dmat_subregion_p) { 265 min_addr = MAX(min_addr, dev->dmat_subregion_min); 266 max_addr = MIN(max_addr, dev->dmat_subregion_max); 267 bus_dmatag_destroy(dev->dmat); 268 } 269 270 /* 271 * Create a DMA tag for a subregion from the bus's DMA tag. If 272 * that fails, restore dev->dmat to the whole region so that we 273 * need not worry about dev->dmat being uninitialized (not that 274 * the caller should try to allocate DMA-safe memory on failure 275 * anyway, but...paranoia). 276 */ 277 /* XXX errno NetBSD->Linux */ 278 ret = -bus_dmatag_subregion(dev->bus_dmat, min_addr, max_addr, 279 &dev->dmat, BUS_DMA_WAITOK); 280 if (ret) { 281 dev->dmat = dev->bus_dmat; 282 dev->dmat_subregion_p = false; 283 return ret; 284 } 285 286 /* 287 * Remember that we have a subregion tag so that we know to 288 * destroy it later, and record the bounds in case we need to 289 * limit them again. 290 */ 291 dev->dmat_subregion_p = true; 292 dev->dmat_subregion_min = min_addr; 293 dev->dmat_subregion_max = max_addr; 294 295 /* Success! */ 296 return 0; 297 } 298