1 /* $NetBSD: drm_memory.c,v 1.8 2015/10/17 15:13:39 jmcneill 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 1.8 2015/10/17 15:13:39 jmcneill Exp $"); 34 35 #if defined(__i386__) || defined(__x86_64__) 36 #define HAS_AGP_I810 1 37 #else 38 #define HAS_AGP_I810 0 39 #endif 40 41 #ifdef _KERNEL_OPT 42 # if HAS_AGP_I810 > 0 43 # include "agp_i810.h" 44 # else 45 # define NAGP_I810 0 46 # endif 47 # include "genfb.h" 48 #else 49 # define NAGP_I810 HAS_AGP_I810 /* XXX WTF? */ 50 # define NGENFB 0 /* XXX WTF? */ 51 #endif 52 53 #include <sys/bus.h> 54 55 #if NAGP_I810 > 0 56 /* XXX include order botch -- shouldn't need to include pcivar.h */ 57 #include <dev/pci/pcivar.h> 58 #include <dev/pci/agpvar.h> 59 #endif 60 61 #if NGENFB > 0 62 #include <dev/wsfb/genfbvar.h> 63 #endif 64 65 #include <drm/drmP.h> 66 67 /* 68 * XXX drm_bus_borrow is a horrible kludge! 69 */ 70 static bool 71 drm_bus_borrow(bus_addr_t base, bus_size_t size, bus_space_handle_t *handlep) 72 { 73 74 #if NAGP_I810 > 0 75 if (agp_i810_borrow(base, size, handlep)) 76 return true; 77 #endif 78 79 #if NGENFB > 0 80 if (genfb_borrow(base, handlep)) 81 return true; 82 #endif 83 84 return false; 85 } 86 87 void 88 drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev) 89 { 90 const bus_space_tag_t bst = dev->bst; 91 unsigned int unit; 92 93 /* 94 * Search dev's bus maps for a match. 95 */ 96 for (unit = 0; unit < dev->bus_nmaps; unit++) { 97 struct drm_bus_map *const bm = &dev->bus_maps[unit]; 98 int flags = bm->bm_flags; 99 100 /* Reject maps starting after the request. */ 101 if (map->offset < bm->bm_base) 102 continue; 103 104 /* Reject maps smaller than the request. */ 105 if (bm->bm_size < map->size) 106 continue; 107 108 /* Reject maps that the request doesn't fit in. */ 109 if ((bm->bm_size - map->size) < 110 (map->offset - bm->bm_base)) 111 continue; 112 113 /* Ensure we can map the space into virtual memory. */ 114 if (!ISSET(flags, BUS_SPACE_MAP_LINEAR)) 115 continue; 116 117 /* Reflect requested flags in the bus_space map. */ 118 if (ISSET(map->flags, _DRM_WRITE_COMBINING)) 119 flags |= BUS_SPACE_MAP_PREFETCHABLE; 120 121 /* Map it. */ 122 if (bus_space_map(bst, map->offset, map->size, flags, 123 &map->lm_data.bus_space.bsh)) 124 break; 125 126 map->lm_data.bus_space.bus_map = bm; 127 goto win; 128 } 129 130 /* Couldn't map it. Try borrowing from someone else. */ 131 if (drm_bus_borrow(map->offset, map->size, 132 &map->lm_data.bus_space.bsh)) { 133 map->lm_data.bus_space.bus_map = NULL; 134 goto win; 135 } 136 137 /* Failure! */ 138 return; 139 140 win: map->lm_data.bus_space.bst = bst; 141 map->handle = bus_space_vaddr(bst, map->lm_data.bus_space.bsh); 142 } 143 144 void 145 drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev) 146 { 147 if (map->lm_data.bus_space.bus_map != NULL) { 148 bus_space_unmap(map->lm_data.bus_space.bst, 149 map->lm_data.bus_space.bsh, map->size); 150 map->lm_data.bus_space.bus_map = NULL; 151 map->handle = NULL; 152 } 153 } 154 155 /* 156 * Allocate a drm dma handle, allocate memory fit for DMA, and map it. 157 * 158 * XXX This is called drm_pci_alloc for hysterical raisins; it is not 159 * specific to PCI. 160 * 161 * XXX For now, we use non-blocking allocations because this is called 162 * by ioctls with the drm global mutex held. 163 * 164 * XXX Error information is lost because this returns NULL on failure, 165 * not even an error embedded in a pointer. 166 */ 167 struct drm_dma_handle * 168 drm_pci_alloc(struct drm_device *dev, size_t size, size_t align) 169 { 170 int nsegs; 171 int error; 172 173 /* 174 * Allocate a drm_dma_handle record. 175 */ 176 struct drm_dma_handle *const dmah = kmem_alloc(sizeof(*dmah), 177 KM_NOSLEEP); 178 if (dmah == NULL) { 179 error = -ENOMEM; 180 goto out; 181 } 182 dmah->dmah_tag = dev->dmat; 183 184 /* 185 * Allocate the requested amount of DMA-safe memory. 186 */ 187 /* XXX errno NetBSD->Linux */ 188 error = -bus_dmamem_alloc(dmah->dmah_tag, size, align, 0, 189 &dmah->dmah_seg, 1, &nsegs, BUS_DMA_NOWAIT); 190 if (error) 191 goto fail0; 192 KASSERT(nsegs == 1); 193 194 /* 195 * Map the DMA-safe memory into kernel virtual address space. 196 */ 197 /* XXX errno NetBSD->Linux */ 198 error = -bus_dmamem_map(dmah->dmah_tag, &dmah->dmah_seg, 1, size, 199 &dmah->vaddr, 200 (BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)); 201 if (error) 202 goto fail1; 203 dmah->size = size; 204 205 /* 206 * Create a map for DMA transfers. 207 */ 208 /* XXX errno NetBSD->Linux */ 209 error = -bus_dmamap_create(dmah->dmah_tag, size, 1, size, 0, 210 BUS_DMA_NOWAIT, &dmah->dmah_map); 211 if (error) 212 goto fail2; 213 214 /* 215 * Load the kva buffer into the map for DMA transfers. 216 */ 217 /* XXX errno NetBSD->Linux */ 218 error = -bus_dmamap_load(dmah->dmah_tag, dmah->dmah_map, dmah->vaddr, 219 size, NULL, (BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)); 220 if (error) 221 goto fail3; 222 223 /* Record the bus address for convenient reference. */ 224 dmah->busaddr = dmah->dmah_map->dm_segs[0].ds_addr; 225 226 /* Zero the DMA buffer. XXX Yikes! Is this necessary? */ 227 memset(dmah->vaddr, 0, size); 228 229 /* Success! */ 230 return dmah; 231 232 fail3: bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 233 fail2: bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 234 fail1: bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 235 fail0: dmah->dmah_tag = NULL; /* XXX paranoia */ 236 kmem_free(dmah, sizeof(*dmah)); 237 out: DRM_DEBUG("drm_pci_alloc failed: %d\n", error); 238 return NULL; 239 } 240 241 /* 242 * Release the bus DMA mappings and memory in dmah, and deallocate it. 243 */ 244 void 245 drm_pci_free(struct drm_device *dev, struct drm_dma_handle *dmah) 246 { 247 248 bus_dmamap_unload(dmah->dmah_tag, dmah->dmah_map); 249 bus_dmamap_destroy(dmah->dmah_tag, dmah->dmah_map); 250 bus_dmamem_unmap(dmah->dmah_tag, dmah->vaddr, dmah->size); 251 bus_dmamem_free(dmah->dmah_tag, &dmah->dmah_seg, 1); 252 dmah->dmah_tag = NULL; /* XXX paranoia */ 253 kmem_free(dmah, sizeof(*dmah)); 254 } 255 256 /* 257 * Make sure the DMA-safe memory allocated for dev lies between 258 * min_addr and max_addr. Can be used multiple times to restrict the 259 * bounds further, but never to expand the bounds again. 260 * 261 * XXX Caller must guarantee nobody has used the tag yet, 262 * i.e. allocated any DMA memory. 263 */ 264 int 265 drm_limit_dma_space(struct drm_device *dev, resource_size_t min_addr, 266 resource_size_t max_addr) 267 { 268 int ret; 269 270 KASSERT(min_addr <= max_addr); 271 272 /* 273 * Limit it further if we have already limited it, and destroy 274 * the old subregion DMA tag. 275 */ 276 if (dev->dmat_subregion_p) { 277 min_addr = MAX(min_addr, dev->dmat_subregion_min); 278 max_addr = MIN(max_addr, dev->dmat_subregion_max); 279 bus_dmatag_destroy(dev->dmat); 280 } 281 282 /* 283 * Create a DMA tag for a subregion from the bus's DMA tag. If 284 * that fails, restore dev->dmat to the whole region so that we 285 * need not worry about dev->dmat being uninitialized (not that 286 * the caller should try to allocate DMA-safe memory on failure 287 * anyway, but...paranoia). 288 */ 289 /* XXX errno NetBSD->Linux */ 290 ret = -bus_dmatag_subregion(dev->bus_dmat, min_addr, max_addr, 291 &dev->dmat, BUS_DMA_WAITOK); 292 if (ret) { 293 dev->dmat = dev->bus_dmat; 294 dev->dmat_subregion_p = false; 295 return ret; 296 } 297 298 /* 299 * Remember that we have a subregion tag so that we know to 300 * destroy it later, and record the bounds in case we need to 301 * limit them again. 302 */ 303 dev->dmat_subregion_p = true; 304 dev->dmat_subregion_min = min_addr; 305 dev->dmat_subregion_max = max_addr; 306 307 /* Success! */ 308 return 0; 309 } 310