| 1 | /* $NetBSD: drm_vm.c,v 1.7 2014/12/31 08:55:18 mrg 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 1.7 2014/12/31 08:55:18 mrg 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, voff_t *uoffsetp, struct file *file __unused) |
| 51 | { |
| 52 | devmajor_t maj = cdevsw_lookup_major(&drm_cdevsw); |
| 53 | dev_t devno = makedev(maj, dev->primary->index); |
| 54 | struct uvm_object *uobj; |
| 55 | |
| 56 | KASSERT(offset == (offset & ~(PAGE_SIZE-1))); |
| 57 | |
| 58 | /* |
| 59 | * Attach the device. The size and offset are used only for |
| 60 | * access checks; offset does not become a base address for the |
| 61 | * subsequent uvm_map, hence we set *uoffsetp to offset, not 0. |
| 62 | */ |
| 63 | uobj = udv_attach(devno, prot, offset, size); |
| 64 | if (uobj == NULL) |
| 65 | return -EINVAL; |
| 66 | |
| 67 | *uobjp = uobj; |
| 68 | *uoffsetp = offset; |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | paddr_t |
| 73 | drm_mmap_paddr(struct drm_device *dev, off_t byte_offset, int prot) |
| 74 | { |
| 75 | paddr_t paddr; |
| 76 | |
| 77 | if (byte_offset != (byte_offset & ~(PAGE_SIZE-1))) |
| 78 | return -1; |
| 79 | |
| 80 | mutex_lock(&dev->struct_mutex); |
| 81 | paddr = drm_mmap_paddr_locked(dev, byte_offset, prot); |
| 82 | mutex_unlock(&dev->struct_mutex); |
| 83 | |
| 84 | return paddr; |
| 85 | } |
| 86 | |
| 87 | static paddr_t |
| 88 | drm_mmap_paddr_locked(struct drm_device *dev, off_t byte_offset, int prot) |
| 89 | { |
| 90 | const off_t page_offset = (byte_offset >> PAGE_SHIFT); |
| 91 | struct drm_hash_item *hash; |
| 92 | |
| 93 | KASSERT(mutex_is_locked(&dev->struct_mutex)); |
| 94 | KASSERT(byte_offset == (byte_offset & ~(PAGE_SIZE-1))); |
| 95 | |
| 96 | if ((dev->dma != NULL) && |
| 97 | (0 <= byte_offset) && |
| 98 | (page_offset <= dev->dma->page_count)) |
| 99 | return drm_mmap_dma_paddr(dev, byte_offset, prot); |
| 100 | |
| 101 | if (drm_ht_find_item(&dev->map_hash, page_offset, &hash)) |
| 102 | return -1; |
| 103 | |
| 104 | struct drm_local_map *const map = drm_hash_entry(hash, |
| 105 | struct drm_map_list, hash)->map; |
| 106 | if (map == NULL) |
| 107 | return -1; |
| 108 | |
| 109 | /* |
| 110 | * XXX FreeBSD drops the mutex at this point, which would be |
| 111 | * nice, to allow sleeping in bus_dma cruft, but I don't know |
| 112 | * what guarantees the map will continue to exist. |
| 113 | */ |
| 114 | |
| 115 | if (ISSET(map->flags, _DRM_RESTRICTED) && !DRM_SUSER()) |
| 116 | return -1; |
| 117 | |
| 118 | if (!(map->offset <= byte_offset)) |
| 119 | return -1; |
| 120 | if (map->size < (map->offset - byte_offset)) |
| 121 | return -1; |
| 122 | |
| 123 | return drm_mmap_map_paddr(dev, map, (byte_offset - map->offset), prot); |
| 124 | } |
| 125 | |
| 126 | static paddr_t |
| 127 | drm_mmap_dma_paddr(struct drm_device *dev, off_t byte_offset, int prot) |
| 128 | { |
| 129 | const off_t page_offset = (byte_offset >> PAGE_SHIFT); |
| 130 | |
| 131 | KASSERT(mutex_is_locked(&dev->struct_mutex)); |
| 132 | KASSERT(byte_offset == (byte_offset & ~(PAGE_SIZE-1))); |
| 133 | KASSERT(page_offset <= dev->dma->page_count); |
| 134 | |
| 135 | if (dev->dma->pagelist == NULL) |
| 136 | return (paddr_t)-1; |
| 137 | |
| 138 | return dev->dma->pagelist[page_offset]; |
| 139 | } |
| 140 | |
| 141 | static paddr_t |
| 142 | drm_mmap_map_paddr(struct drm_device *dev, struct drm_local_map *map, |
| 143 | off_t byte_offset, int prot) |
| 144 | { |
| 145 | int flags = 0; |
| 146 | |
| 147 | KASSERT(byte_offset <= map->size); |
| 148 | |
| 149 | switch (map->type) { |
| 150 | case _DRM_FRAME_BUFFER: |
| 151 | case _DRM_AGP: |
| 152 | flags |= BUS_SPACE_MAP_PREFETCHABLE; |
| 153 | /* Fall through. */ |
| 154 | |
| 155 | case _DRM_REGISTERS: |
| 156 | flags |= BUS_SPACE_MAP_LINEAR; /* XXX Why? */ |
| 157 | |
| 158 | return bus_space_mmap(map->lm_data.bus_space.bst, map->offset, |
| 159 | byte_offset, prot, flags); |
| 160 | |
| 161 | case _DRM_CONSISTENT: { |
| 162 | struct drm_dma_handle *const dmah = map->lm_data.dmah; |
| 163 | |
| 164 | return bus_dmamem_mmap(dev->dmat, &dmah->dmah_seg, 1, |
| 165 | byte_offset, prot, |
| 166 | /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ |
| 167 | /* XXX What else? BUS_DMA_COHERENT? */ |
| 168 | (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); |
| 169 | } |
| 170 | |
| 171 | case _DRM_SCATTER_GATHER: { |
| 172 | struct drm_sg_mem *const sg = dev->sg; |
| 173 | |
| 174 | #if 0 /* XXX */ |
| 175 | KASSERT(sg == map->lm_data.sg); |
| 176 | #endif |
| 177 | |
| 178 | return bus_dmamem_mmap(dev->dmat, sg->sg_segs, sg->sg_nsegs, |
| 179 | byte_offset, prot, |
| 180 | /* XXX BUS_DMA_WAITOK? We're holding a mutex... */ |
| 181 | /* XXX What else? BUS_DMA_COHERENT? */ |
| 182 | (BUS_DMA_WAITOK | BUS_DMA_NOCACHE)); |
| 183 | } |
| 184 | |
| 185 | case _DRM_SHM: |
| 186 | default: |
| 187 | return (paddr_t)-1; |
| 188 | } |
| 189 | } |
| 190 | |