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 "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, &gtt->gem, size) != 0)
 260                 goto free_gtt;
 261         if (drm_gem_handle_create(file, &gtt->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