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 <drm/gma_drm.h> 29 #include <drm/drm_vma_manager.h> 30 #include "psb_drv.h" 31 32 int psb_gem_init_object(struct drm_gem_object *obj) 33 { 34 return -EINVAL; 35 } 36 37 void psb_gem_free_object(struct drm_gem_object *obj) 38 { 39 struct gtt_range *gtt = container_of(obj, struct gtt_range, gem); 40 41 /* Remove the list map if one is present */ 42 drm_gem_free_mmap_offset(obj); 43 drm_gem_object_release(obj); 44 45 /* This must occur last as it frees up the memory of the GEM object */ 46 psb_gtt_free_range(obj->dev, gtt); 47 } 48 49 int psb_gem_get_aperture(struct drm_device *dev, void *data, 50 struct drm_file *file) 51 { 52 return -EINVAL; 53 } 54 55 /** 56 * psb_gem_dumb_map_gtt - buffer mapping for dumb interface 57 * @file: our drm client file 58 * @dev: drm device 59 * @handle: GEM handle to the object (from dumb_create) 60 * 61 * Do the necessary setup to allow the mapping of the frame buffer 62 * into user memory. We don't have to do much here at the moment. 63 */ 64 int psb_gem_dumb_map_gtt(struct drm_file *file, struct drm_device *dev, 65 uint32_t handle, uint64_t *offset) 66 { 67 int ret = 0; 68 struct drm_gem_object *obj; 69 70 if (!(dev->driver->driver_features & DRIVER_GEM)) 71 return -ENODEV; 72 73 mutex_lock(&dev->struct_mutex); 74 75 /* GEM does all our handle to object mapping */ 76 obj = drm_gem_object_lookup(dev, file, handle); 77 if (obj == NULL) { 78 ret = -ENOENT; 79 goto unlock; 80 } 81 /* What validation is needed here ? */ 82 83 /* Make it mmapable */ 84 ret = drm_gem_create_mmap_offset(obj); 85 if (ret) 86 goto out; 87 *offset = drm_vma_node_offset_addr(&obj->vma_node); 88 out: 89 drm_gem_object_unreference(obj); 90 unlock: 91 mutex_unlock(&dev->struct_mutex); 92 return ret; 93 } 94 95 /** 96 * psb_gem_create - create a mappable object 97 * @file: the DRM file of the client 98 * @dev: our device 99 * @size: the size requested 100 * @handlep: returned handle (opaque number) 101 * 102 * Create a GEM object, fill in the boilerplate and attach a handle to 103 * it so that userspace can speak about it. This does the core work 104 * for the various methods that do/will create GEM objects for things 105 */ 106 static int psb_gem_create(struct drm_file *file, 107 struct drm_device *dev, uint64_t size, uint32_t *handlep) 108 { 109 struct gtt_range *r; 110 int ret; 111 u32 handle; 112 113 size = roundup(size, PAGE_SIZE); 114 115 /* Allocate our object - for now a direct gtt range which is not 116 stolen memory backed */ 117 r = psb_gtt_alloc_range(dev, size, "gem", 0); 118 if (r == NULL) { 119 dev_err(dev->dev, "no memory for %lld byte GEM object\n", size); 120 return -ENOSPC; 121 } 122 /* Initialize the extra goodies GEM needs to do all the hard work */ 123 if (drm_gem_object_init(dev, &r->gem, size) != 0) { 124 psb_gtt_free_range(dev, r); 125 /* GEM doesn't give an error code so use -ENOMEM */ 126 dev_err(dev->dev, "GEM init failed for %lld\n", size); 127 return -ENOMEM; 128 } 129 /* Limit the object to 32bit mappings */ 130 mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32); 131 /* Give the object a handle so we can carry it more easily */ 132 ret = drm_gem_handle_create(file, &r->gem, &handle); 133 if (ret) { 134 dev_err(dev->dev, "GEM handle failed for %p, %lld\n", 135 &r->gem, size); 136 drm_gem_object_release(&r->gem); 137 psb_gtt_free_range(dev, r); 138 return ret; 139 } 140 /* We have the initial and handle reference but need only one now */ 141 drm_gem_object_unreference(&r->gem); 142 *handlep = handle; 143 return 0; 144 } 145 146 /** 147 * psb_gem_dumb_create - create a dumb buffer 148 * @drm_file: our client file 149 * @dev: our device 150 * @args: the requested arguments copied from userspace 151 * 152 * Allocate a buffer suitable for use for a frame buffer of the 153 * form described by user space. Give userspace a handle by which 154 * to reference it. 155 */ 156 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev, 157 struct drm_mode_create_dumb *args) 158 { 159 args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64); 160 args->size = args->pitch * args->height; 161 return psb_gem_create(file, dev, args->size, &args->handle); 162 } 163 164 /** 165 * psb_gem_fault - pagefault handler for GEM objects 166 * @vma: the VMA of the GEM object 167 * @vmf: fault detail 168 * 169 * Invoked when a fault occurs on an mmap of a GEM managed area. GEM 170 * does most of the work for us including the actual map/unmap calls 171 * but we need to do the actual page work. 172 * 173 * This code eventually needs to handle faulting objects in and out 174 * of the GTT and repacking it when we run out of space. We can put 175 * that off for now and for our simple uses 176 * 177 * The VMA was set up by GEM. In doing so it also ensured that the 178 * vma->vm_private_data points to the GEM object that is backing this 179 * mapping. 180 */ 181 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 182 { 183 struct drm_gem_object *obj; 184 struct gtt_range *r; 185 int ret; 186 unsigned long pfn; 187 pgoff_t page_offset; 188 struct drm_device *dev; 189 struct drm_psb_private *dev_priv; 190 191 obj = vma->vm_private_data; /* GEM object */ 192 dev = obj->dev; 193 dev_priv = dev->dev_private; 194 195 r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */ 196 197 /* Make sure we don't parallel update on a fault, nor move or remove 198 something from beneath our feet */ 199 mutex_lock(&dev->struct_mutex); 200 201 /* For now the mmap pins the object and it stays pinned. As things 202 stand that will do us no harm */ 203 if (r->mmapping == 0) { 204 ret = psb_gtt_pin(r); 205 if (ret < 0) { 206 dev_err(dev->dev, "gma500: pin failed: %d\n", ret); 207 goto fail; 208 } 209 r->mmapping = 1; 210 } 211 212 /* Page relative to the VMA start - we must calculate this ourselves 213 because vmf->pgoff is the fake GEM offset */ 214 page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start) 215 >> PAGE_SHIFT; 216 217 /* CPU view of the page, don't go via the GART for CPU writes */ 218 if (r->stolen) 219 pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT; 220 else 221 pfn = page_to_pfn(r->pages[page_offset]); 222 ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); 223 224 fail: 225 mutex_unlock(&dev->struct_mutex); 226 switch (ret) { 227 case 0: 228 case -ERESTARTSYS: 229 case -EINTR: 230 return VM_FAULT_NOPAGE; 231 case -ENOMEM: 232 return VM_FAULT_OOM; 233 default: 234 return VM_FAULT_SIGBUS; 235 } 236 } 237 238 static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev, 239 int size, u32 *handle) 240 { 241 struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1); 242 if (gtt == NULL) 243 return -ENOMEM; 244 245 drm_gem_private_object_init(dev, >t->gem, size); 246 if (drm_gem_handle_create(file, >t->gem, handle) == 0) 247 return 0; 248 249 drm_gem_object_release(>t->gem); 250 psb_gtt_free_range(dev, gtt); 251 return -ENOMEM; 252 } 253 254 /* 255 * GEM interfaces for our specific client 256 */ 257 int psb_gem_create_ioctl(struct drm_device *dev, void *data, 258 struct drm_file *file) 259 { 260 struct drm_psb_gem_create *args = data; 261 int ret; 262 if (args->flags & GMA_GEM_CREATE_STOLEN) { 263 ret = psb_gem_create_stolen(file, dev, args->size, 264 &args->handle); 265 if (ret == 0) 266 return 0; 267 /* Fall throguh */ 268 args->flags &= ~GMA_GEM_CREATE_STOLEN; 269 } 270 return psb_gem_create(file, dev, args->size, &args->handle); 271 } 272 273 int psb_gem_mmap_ioctl(struct drm_device *dev, void *data, 274 struct drm_file *file) 275 { 276 struct drm_psb_gem_mmap *args = data; 277 return dev->driver->dumb_map_offset(file, dev, 278 args->handle, &args->offset); 279 } 280 281