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 <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, &gtt->gem, size);
 246         if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
 247                 return 0;
 248
 249         drm_gem_object_release(&gtt->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