1 /* 2 * psb GEM interface 3 * 4 * Copyright (c) 2011, Intel Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program; if not, write to the Free Software Foundation, Inc., 17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Authors: Alan Cox 20 * 21 * TODO: 22 * - we need to work out if the MMU is relevant (eg for 23 * accelerated operations on a GEM object) 24 */ 25 26 #include <drm/drmP.h> 27 #include <drm/drm.h> 28 #include "gma_drm.h" 29 #include "psb_drv.h" 30 31 int psb_gem_init_object(struct drm_gem_object *obj) 32 { 33 return -EINVAL; 34 } 35 36 void psb_gem_free_object(struct drm_gem_object *obj) 37 { 38 struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); 39 drm_gem_object_release_wrap(obj); 40 /* This must occur last as it frees up the memory of the GEM object */ 41 psb_gtt_free_range(obj->dev, gtt); 42 } 43 44 int psb_gem_get_aperture(struct drm_device *dev, void *data, 45 struct drm_file *file) 46 { 47 return -EINVAL; 48 } 49 50 /** 51 * psb_gem_dumb_map_gtt - buffer mapping for dumb interface 52 * @file: our drm client file 53 * @dev: drm device 54 * @handle: GEM handle to the object (from dumb_create) 55 * 56 * Do the necessary setup to allow the mapping of the frame buffer 57 * into user memory. We don't have to do much here at the moment. 58 */ 59 int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev, 60 uint32_t handle, uint64_t *offset) 61 { 62 int ret = 0; 63 struct drm_gem_object *obj; 64 65 if (!(dev->driver->driver_features & DRIVER_GEM)) 66 return -ENODEV; 67 68 mutex_lock(&dev->struct_mutex); 69 70 /* GEM does all our handle to object mapping */ 71 obj = drm_gem_object_lookup(dev, file, handle); 72 if (obj == NULL) { 73 ret = -ENOENT; 74 goto unlock; 75 } 76 /* What validation is needed here ? */ 77 78 /* Make it mmapable */ 79 if (!obj->map_list.map) { 80 ret = gem_create_mmap_offset(obj); 81 if (ret) 82 goto out; 83 } 84 /* GEM should really work out the hash offsets for us */ 85 *offset = (u64)obj->map_list.hash.key << PAGE_SHIFT; 86 out: 87 drm_gem_object_unreference(obj); 88 unlock: 89 mutex_unlock(&dev->struct_mutex); 90 return ret; 91 } 92 93 /** 94 * psb_gem_create - create a mappable object 95 * @file: the DRM file of the client 96 * @dev: our device 97 * @size: the size requested 98 * @handlep: returned handle (opaque number) 99 * 100 * Create a GEM object, fill in the boilerplate and attach a handle to 101 * it so that userspace can speak about it. This does the core work 102 * for the various methods that do/will create GEM objects for things 103 */ 104 static int psb_gem_create(struct drm_file *file, 105 struct drm_device *dev, uint64_t size, uint32_t *handlep) 106 { 107 struct gtt_range *r; 108 int ret; 109 u32 handle; 110 111 size = roundup(size, PAGE_SIZE); 112 113 /* Allocate our object - for now a direct gtt range which is not 114 stolen memory backed */ 115 r = psb_gtt_alloc_range(dev, size, "gem", 0); 116 if (r == NULL) { 117 dev_err(dev->dev, "no memory for %lld byte GEM object\n", size); 118 return -ENOSPC; 119 } 120 /* Initialize the extra goodies GEM needs to do all the hard work */ 121 if (drm_gem_object_init(dev, &r->gem, size) != 0) { 122 psb_gtt_free_range(dev, r); 123 /* GEM doesn't give an error code so use -ENOMEM */ 124 dev_err(dev->dev, "GEM init failed for %lld\n", size); 125 return -ENOMEM; 126 } 127 /* Limit the object to 32bit mappings */ 128 mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32); 129 /* Give the object a handle so we can carry it more easily */ 130 ret = drm_gem_handle_create(file, &r->gem, &handle); 131 if (ret) { 132 dev_err(dev->dev, "GEM handle failed for %p, %lld\n", 133 &r->gem, size); 134 drm_gem_object_release(&r->gem); 135 psb_gtt_free_range(dev, r); 136 return ret; 137 } 138 /* We have the initial and handle reference but need only one now */ 139 drm_gem_object_unreference(&r->gem); 140 *handlep = handle; 141 return 0; 142 } 143 144 /** 145 * psb_gem_dumb_create - create a dumb buffer 146 * @drm_file: our client file 147 * @dev: our device 148 * @args: the requested arguments copied from userspace 149 * 150 * Allocate a buffer suitable for use for a frame buffer of the 151 * form described by user space. Give userspace a handle by which 152 * to reference it. 153 */ 154 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev, 155 struct drm_mode_create_dumb *args) 156 { 157 args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64); 158 args->size = args->pitch * args->height; 159 return psb_gem_create(file, dev, args->size, &args->handle); 160 } 161 162 /** 163 * psb_gem_dumb_destroy - destroy a dumb buffer 164 * @file: client file 165 * @dev: our DRM device 166 * @handle: the object handle 167 * 168 * Destroy a handle that was created via psb_gem_dumb_create, at least 169 * we hope it was created that way. i915 seems to assume the caller 170 * does the checking but that might be worth review ! FIXME 171 */ 172 int psb_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev, 173 uint32_t handle) 174 { 175 /* No special work needed, drop the reference and see what falls out */ 176 return drm_gem_handle_delete(file, handle); 177 } 178 179 /** 180 * psb_gem_fault - pagefault handler for GEM objects 181 * @vma: the VMA of the GEM object 182 * @vmf: fault detail 183 * 184 * Invoked when a fault occurs on an mmap of a GEM managed area. GEM 185 * does most of the work for us including the actual map/unmap calls 186 * but we need to do the actual page work. 187 * 188 * This code eventually needs to handle faulting objects in and out 189 * of the GTT and repacking it when we run out of space. We can put 190 * that off for now and for our simple uses 191 * 192 * The VMA was set up by GEM. In doing so it also ensured that the 193 * vma->vm_private_data points to the GEM object that is backing this 194 * mapping. 195 */ 196 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 197 { 198 struct drm_gem_object *obj; 199 struct gtt_range *r; 200 int ret; 201 unsigned long pfn; 202 pgoff_t page_offset; 203 struct drm_device *dev; 204 struct drm_psb_private *dev_priv; 205 206 obj = vma->vm_private_data; /* GEM object */ 207 dev = obj->dev; 208 dev_priv = dev->dev_private; 209 210 r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */ 211 212 /* Make sure we don't parallel update on a fault, nor move or remove 213 something from beneath our feet */ 214 mutex_lock(&dev->struct_mutex); 215 216 /* For now the mmap pins the object and it stays pinned. As things 217 stand that will do us no harm */ 218 if (r->mmapping == 0) { 219 ret = psb_gtt_pin(r); 220 if (ret < 0) { 221 dev_err(dev->dev, "gma500: pin failed: %d\n", ret); 222 goto fail; 223 } 224 r->mmapping = 1; 225 } 226 227 /* Page relative to the VMA start - we must calculate this ourselves 228 because vmf->pgoff is the fake GEM offset */ 229 page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start) 230 >> PAGE_SHIFT; 231 232 /* CPU view of the page, don't go via the GART for CPU writes */ 233 if (r->stolen) 234 pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT; 235 else 236 pfn = page_to_pfn(r->pages[page_offset]); 237 ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); 238 239 fail: 240 mutex_unlock(&dev->struct_mutex); 241 switch (ret) { 242 case 0: 243 case -ERESTARTSYS: 244 case -EINTR: 245 return VM_FAULT_NOPAGE; 246 case -ENOMEM: 247 return VM_FAULT_OOM; 248 default: 249 return VM_FAULT_SIGBUS; 250 } 251 } 252 253 static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev, 254 int size, u32 *handle) 255 { 256 struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1); 257 if (gtt == NULL) 258 return -ENOMEM; 259 if (drm_gem_private_object_init(dev, >t->gem, size) != 0) 260 goto free_gtt; 261 if (drm_gem_handle_create(file, >t->gem, handle) == 0) 262 return 0; 263 free_gtt: 264 psb_gtt_free_range(dev, gtt); 265 return -ENOMEM; 266 } 267 268 /* 269 * GEM interfaces for our specific client 270 */ 271 int psb_gem_create_ioctl(struct drm_device *dev, void *data, 272 struct drm_file *file) 273 { 274 struct drm_psb_gem_create *args = data; 275 int ret; 276 if (args->flags & GMA_GEM_CREATE_STOLEN) { 277 ret = psb_gem_create_stolen(file, dev, args->size, 278 &args->handle); 279 if (ret == 0) 280 return 0; 281 /* Fall throguh */ 282 args->flags &= ~GMA_GEM_CREATE_STOLEN; 283 } 284 return psb_gem_create(file, dev, args->size, &args->handle); 285 } 286 287 int psb_gem_mmap_ioctl(struct drm_device *dev, void *data, 288 struct drm_file *file) 289 { 290 struct drm_psb_gem_mmap *args = data; 291 return dev->driver->dumb_map_offset(file, dev, 292 args->handle, &args->offset); 293 } 294 295