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 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, &gtt->gem, size);
 241         if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
 242                 return 0;
 243
 244         drm_gem_object_release(&gtt->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