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