drivers/gpu/drm/gma500/gem.c

   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 "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
  40         /* Remove the list map if one is present */
  41         if (obj->map_list.map)
  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         if (!obj->map_list.map) {
  85                 ret = drm_gem_create_mmap_offset(obj);
  86                 if (ret)
  87                         goto out;
  88         }
  89         /* GEM should really work out the hash offsets for us */
  90         *offset = (u64)obj->map_list.hash.key << PAGE_SHIFT;
  91 out:
  92         drm_gem_object_unreference(obj);
  93 unlock:
  94         mutex_unlock(&dev->struct_mutex);
  95         return ret;
  96 }
  97
  98 /**
  99  *      psb_gem_create          -       create a mappable object
 100  *      @file: the DRM file of the client
 101  *      @dev: our device
 102  *      @size: the size requested
 103  *      @handlep: returned handle (opaque number)
 104  *
 105  *      Create a GEM object, fill in the boilerplate and attach a handle to
 106  *      it so that userspace can speak about it. This does the core work
 107  *      for the various methods that do/will create GEM objects for things
 108  */
 109 static int psb_gem_create(struct drm_file *file,
 110         struct drm_device *dev, uint64_t size, uint32_t *handlep)
 111 {
 112         struct gtt_range *r;
 113         int ret;
 114         u32 handle;
 115
 116         size = roundup(size, PAGE_SIZE);
 117
 118         /* Allocate our object - for now a direct gtt range which is not
 119            stolen memory backed */
 120         r = psb_gtt_alloc_range(dev, size, "gem", 0);
 121         if (r == NULL) {
 122                 dev_err(dev->dev, "no memory for %lld byte GEM object\n", size);
 123                 return -ENOSPC;
 124         }
 125         /* Initialize the extra goodies GEM needs to do all the hard work */
 126         if (drm_gem_object_init(dev, &r->gem, size) != 0) {
 127                 psb_gtt_free_range(dev, r);
 128                 /* GEM doesn't give an error code so use -ENOMEM */
 129                 dev_err(dev->dev, "GEM init failed for %lld\n", size);
 130                 return -ENOMEM;
 131         }
 132         /* Limit the object to 32bit mappings */
 133         mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32);
 134         /* Give the object a handle so we can carry it more easily */
 135         ret = drm_gem_handle_create(file, &r->gem, &handle);
 136         if (ret) {
 137                 dev_err(dev->dev, "GEM handle failed for %p, %lld\n",
 138                                                         &r->gem, size);
 139                 drm_gem_object_release(&r->gem);
 140                 psb_gtt_free_range(dev, r);
 141                 return ret;
 142         }
 143         /* We have the initial and handle reference but need only one now */
 144         drm_gem_object_unreference(&r->gem);
 145         *handlep = handle;
 146         return 0;
 147 }
 148
 149 /**
 150  *      psb_gem_dumb_create     -       create a dumb buffer
 151  *      @drm_file: our client file
 152  *      @dev: our device
 153  *      @args: the requested arguments copied from userspace
 154  *
 155  *      Allocate a buffer suitable for use for a frame buffer of the
 156  *      form described by user space. Give userspace a handle by which
 157  *      to reference it.
 158  */
 159 int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 160                         struct drm_mode_create_dumb *args)
 161 {
 162         args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64);
 163         args->size = args->pitch * args->height;
 164         return psb_gem_create(file, dev, args->size, &args->handle);
 165 }
 166
 167 /**
 168  *      psb_gem_dumb_destroy    -       destroy a dumb buffer
 169  *      @file: client file
 170  *      @dev: our DRM device
 171  *      @handle: the object handle
 172  *
 173  *      Destroy a handle that was created via psb_gem_dumb_create, at least
 174  *      we hope it was created that way. i915 seems to assume the caller
 175  *      does the checking but that might be worth review ! FIXME
 176  */
 177 int psb_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev,
 178                         uint32_t handle)
 179 {
 180         /* No special work needed, drop the reference and see what falls out */
 181         return drm_gem_handle_delete(file, handle);
 182 }
 183
 184 /**
 185  *      psb_gem_fault           -       pagefault handler for GEM objects
 186  *      @vma: the VMA of the GEM object
 187  *      @vmf: fault detail
 188  *
 189  *      Invoked when a fault occurs on an mmap of a GEM managed area. GEM
 190  *      does most of the work for us including the actual map/unmap calls
 191  *      but we need to do the actual page work.
 192  *
 193  *      This code eventually needs to handle faulting objects in and out
 194  *      of the GTT and repacking it when we run out of space. We can put
 195  *      that off for now and for our simple uses
 196  *
 197  *      The VMA was set up by GEM. In doing so it also ensured that the
 198  *      vma->vm_private_data points to the GEM object that is backing this
 199  *      mapping.
 200  */
 201 int psb_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 202 {
 203         struct drm_gem_object *obj;
 204         struct gtt_range *r;
 205         int ret;
 206         unsigned long pfn;
 207         pgoff_t page_offset;
 208         struct drm_device *dev;
 209         struct drm_psb_private *dev_priv;
 210
 211         obj = vma->vm_private_data;     /* GEM object */
 212         dev = obj->dev;
 213         dev_priv = dev->dev_private;
 214
 215         r = container_of(obj, struct gtt_range, gem);   /* Get the gtt range */
 216
 217         /* Make sure we don't parallel update on a fault, nor move or remove
 218            something from beneath our feet */
 219         mutex_lock(&dev->struct_mutex);
 220
 221         /* For now the mmap pins the object and it stays pinned. As things
 222            stand that will do us no harm */
 223         if (r->mmapping == 0) {
 224                 ret = psb_gtt_pin(r);
 225                 if (ret < 0) {
 226                         dev_err(dev->dev, "gma500: pin failed: %d\n", ret);
 227                         goto fail;
 228                 }
 229                 r->mmapping = 1;
 230         }
 231
 232         /* Page relative to the VMA start - we must calculate this ourselves
 233            because vmf->pgoff is the fake GEM offset */
 234         page_offset = ((unsigned long) vmf->virtual_address - vma->vm_start)
 235                                 >> PAGE_SHIFT;
 236
 237         /* CPU view of the page, don't go via the GART for CPU writes */
 238         if (r->stolen)
 239                 pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT;
 240         else
 241                 pfn = page_to_pfn(r->pages[page_offset]);
 242         ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
 243
 244 fail:
 245         mutex_unlock(&dev->struct_mutex);
 246         switch (ret) {
 247         case 0:
 248         case -ERESTARTSYS:
 249         case -EINTR:
 250                 return VM_FAULT_NOPAGE;
 251         case -ENOMEM:
 252                 return VM_FAULT_OOM;
 253         default:
 254                 return VM_FAULT_SIGBUS;
 255         }
 256 }
 257
 258 static int psb_gem_create_stolen(struct drm_file *file, struct drm_device *dev,
 259                                                 int size, u32 *handle)
 260 {
 261         struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1);
 262         if (gtt == NULL)
 263                 return -ENOMEM;
 264         if (drm_gem_private_object_init(dev, &gtt->gem, size) != 0)
 265                 goto free_gtt;
 266         if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
 267                 return 0;
 268 free_gtt:
 269         psb_gtt_free_range(dev, gtt);
 270         return -ENOMEM;
 271 }
 272
 273 /*
 274  *      GEM interfaces for our specific client
 275  */
 276 int psb_gem_create_ioctl(struct drm_device *dev, void *data,
 277                                         struct drm_file *file)
 278 {
 279         struct drm_psb_gem_create *args = data;
 280         int ret;
 281         if (args->flags & GMA_GEM_CREATE_STOLEN) {
 282                 ret = psb_gem_create_stolen(file, dev, args->size,
 283                                                         &args->handle);
 284                 if (ret == 0)
 285                         return 0;
 286                 /* Fall throguh */
 287                 args->flags &= ~GMA_GEM_CREATE_STOLEN;
 288         }
 289         return psb_gem_create(file, dev, args->size, &args->handle);
 290 }
 291
 292 int psb_gem_mmap_ioctl(struct drm_device *dev, void *data,
 293                                         struct drm_file *file)
 294 {
 295         struct drm_psb_gem_mmap *args = data;
 296         return dev->driver->dumb_map_offset(file, dev,
 297                                                 args->handle, &args->offset);
 298 }
 299