1 /* $NetBSD: drm_vm.c,v 1.2 2014/03/18 18:20:42 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_vm.c,v 1.2 2014/03/18 18:20:42 riastradh Exp $"); 34 35 #include <sys/types.h> 36 #include <sys/conf.h> 37 38 #include <uvm/uvm_extern.h> 39 #include <uvm/uvm_device.h> 40 41 #include <drm/drmP.h> 42 43 static paddr_t drm_mmap_paddr_locked(struct drm_device *, off_t, int); 44 static paddr_t drm_mmap_dma_paddr(struct drm_device *, off_t, int); 45 static paddr_t drm_mmap_map_paddr(struct drm_device *, struct drm_local_map *, 46 off_t, int); 47 48 int 49 drm_mmap_object(struct drm_device *dev, off_t offset, size_t size, int prot, 50 struct uvm_object **uobjp) 51 { 52 dev_t devno = cdevsw_lookup_major(&drm_cdevsw); 53 struct uvm_object *uobj; 54 55 uobj = udv_attach(&devno, prot, offset, size); 56 if (uobj == NULL) 57 return -EINVAL; 58 59 *uobjp = uobj; 60 return 0; 61 } 62 63 paddr_t 64 drm_mmap_paddr(struct drm_device *dev, off_t byte_offset, int prot) 65 { 66 paddr_t paddr; 67 68 mutex_lock(&dev->struct_mutex); 69 paddr = drm_mmap_paddr_locked(dev, byte_offset, prot); 70 mutex_unlock(&dev->struct_mutex); 71 72 return paddr; 73 } 74 75 static paddr_t 76 drm_mmap_paddr_locked(struct drm_device *dev, off_t byte_offset, int prot) 77 { 78 const off_t page_offset = (byte_offset >> PAGE_SHIFT); 79 struct drm_hash_item *hash; 80 81 KASSERT(mutex_is_locked(&dev->struct_mutex)); 82 83 if (byte_offset != (byte_offset & ~(PAGE_SIZE-1))) 84 return -1; 85 86 if ((dev->dma != NULL) && 87 (0 <= byte_offset) && 88 (byte_offset <= (dev->dma->page_count << PAGE_SHIFT))) 89 return drm_mmap_dma_paddr(dev, byte_offset, prot); 90 91 if (drm_ht_find_item(&dev->map_hash, page_offset, &hash)) 92 return -1; 93 94 struct drm_local_map *const map = drm_hash_entry(hash, 95 struct drm_map_list, hash)->map; 96 if (map == NULL) 97 return -1; 98 99 /* 100 * XXX FreeBSD drops the mutex at this point, which would be 101 * nice, to allow sleeping in bus_dma cruft, but I don't know 102 * what guarantees the map will continue to exist. 103 */ 104 105 if (ISSET(map->flags, _DRM_RESTRICTED) && !DRM_SUSER()) 106 return -1; 107 108 if (byte_offset < map->offset) 109 return -1; 110 111 return drm_mmap_map_paddr(dev, map, (map->offset - byte_offset), 112 prot); 113 } 114 115 static paddr_t 116 drm_mmap_dma_paddr(struct drm_device *dev, off_t byte_offset, int prot) 117 { 118 const off_t page_offset = (byte_offset >> PAGE_SHIFT); 119 120 KASSERT(mutex_is_locked(&dev->struct_mutex)); 121 122 if (dev->dma->pagelist == NULL) 123 return (paddr_t)-1; 124 125 if (page_offset >= dev->dma->page_count) 126 return (paddr_t)-1; 127 128 return dev->dma->pagelist[page_offset]; 129 } 130 131 static paddr_t 132 drm_mmap_map_paddr(struct drm_device *dev, struct drm_local_map *map, 133 off_t byte_offset, int prot) 134 { 135 int flags = 0; 136 137 switch (map->type) { 138 case _DRM_FRAME_BUFFER: 139 case _DRM_AGP: 140 flags |= BUS_SPACE_MAP_PREFETCHABLE; 141 /* Fall through. */ 142 143 case _DRM_REGISTERS: 144 flags |= BUS_SPACE_MAP_LINEAR; /* XXX Why? */ 145 146 return bus_space_mmap(dev->bst, map->offset, byte_offset, prot, 147 flags); 148 149 case _DRM_CONSISTENT: { 150 struct drm_dma_handle *const dmah = map->lm_data.dmah; 151 152 return bus_dmamem_mmap(dev->dmat, &dmah->dmah_seg, 1, 153 byte_offset, prot, 154 /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ 155 /* XXX What else? BUS_DMA_COHERENT? */ 156 (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); 157 } 158 159 case _DRM_SCATTER_GATHER: { 160 struct drm_sg_mem *const sg = dev->sg; 161 162 #if 0 /* XXX */ 163 KASSERT(sg == map->lm_data.sg); 164 #endif 165 166 return bus_dmamem_mmap(dev->dmat, sg->sg_segs, sg->sg_nsegs, 167 byte_offset, prot, 168 /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ 169 /* XXX What else? BUS_DMA_COHERENT? */ 170 (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); 171 } 172 173 case _DRM_SHM: 174 case _DRM_GEM: 175 default: 176 return (paddr_t)-1; 177 } 178 } 179