drivers/gpu/drm/omapdrm/omap_fbdev.c

   1 /*
   2  * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
   3  * Author: Rob Clark <rob@ti.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <drm/drm_crtc.h>
  19 #include <drm/drm_fb_helper.h>
  20
  21 #include "omap_drv.h"
  22
  23 MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')");
  24 static bool ywrap_enabled = true;
  25 module_param_named(ywrap, ywrap_enabled, bool, 0644);
  26
  27 /*
  28  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
  29  */
  30
  31 #define to_omap_fbdev(x) container_of(x, struct omap_fbdev, base)
  32
  33 struct omap_fbdev {
  34         struct drm_fb_helper base;
  35         struct drm_framebuffer *fb;
  36         struct drm_gem_object *bo;
  37         bool ywrap_enabled;
  38
  39         /* for deferred dmm roll when getting called in atomic ctx */
  40         struct work_struct work;
  41 };
  42
  43 static struct drm_fb_helper *get_fb(struct fb_info *fbi);
  44
  45 static void pan_worker(struct work_struct *work)
  46 {
  47         struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
  48         struct fb_info *fbi = fbdev->base.fbdev;
  49         int npages;
  50
  51         /* DMM roll shifts in 4K pages: */
  52         npages = fbi->fix.line_length >> PAGE_SHIFT;
  53         omap_gem_roll(fbdev->bo, fbi->var.yoffset * npages);
  54 }
  55
  56 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var,
  57                 struct fb_info *fbi)
  58 {
  59         struct drm_fb_helper *helper = get_fb(fbi);
  60         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
  61
  62         if (!helper)
  63                 goto fallback;
  64
  65         if (!fbdev->ywrap_enabled)
  66                 goto fallback;
  67
  68         if (drm_can_sleep()) {
  69                 pan_worker(&fbdev->work);
  70         } else {
  71                 struct omap_drm_private *priv = helper->dev->dev_private;
  72                 queue_work(priv->wq, &fbdev->work);
  73         }
  74
  75         return 0;
  76
  77 fallback:
  78         return drm_fb_helper_pan_display(var, fbi);
  79 }
  80
  81 static struct fb_ops omap_fb_ops = {
  82         .owner = THIS_MODULE,
  83         DRM_FB_HELPER_DEFAULT_OPS,
  84
  85         .fb_read = drm_fb_helper_sys_read,
  86         .fb_write = drm_fb_helper_sys_write,
  87         .fb_fillrect = drm_fb_helper_sys_fillrect,
  88         .fb_copyarea = drm_fb_helper_sys_copyarea,
  89         .fb_imageblit = drm_fb_helper_sys_imageblit,
  90
  91         .fb_pan_display = omap_fbdev_pan_display,
  92 };
  93
  94 static int omap_fbdev_create(struct drm_fb_helper *helper,
  95                 struct drm_fb_helper_surface_size *sizes)
  96 {
  97         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
  98         struct drm_device *dev = helper->dev;
  99         struct omap_drm_private *priv = dev->dev_private;
 100         struct drm_framebuffer *fb = NULL;
 101         union omap_gem_size gsize;
 102         struct fb_info *fbi = NULL;
 103         struct drm_mode_fb_cmd2 mode_cmd = {0};
 104         dma_addr_t dma_addr;
 105         int ret;
 106
 107         sizes->surface_bpp = 32;
 108         sizes->surface_depth = 24;
 109
 110         DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
 111                         sizes->surface_height, sizes->surface_bpp,
 112                         sizes->fb_width, sizes->fb_height);
 113
 114         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 115                         sizes->surface_depth);
 116
 117         mode_cmd.width = sizes->surface_width;
 118         mode_cmd.height = sizes->surface_height;
 119
 120         mode_cmd.pitches[0] =
 121                         DIV_ROUND_UP(mode_cmd.width * sizes->surface_bpp, 8);
 122
 123         fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
 124         if (fbdev->ywrap_enabled) {
 125                 /* need to align pitch to page size if using DMM scrolling */
 126                 mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]);
 127         }
 128
 129         /* allocate backing bo */
 130         gsize = (union omap_gem_size){
 131                 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
 132         };
 133         DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
 134         fbdev->bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
 135         if (!fbdev->bo) {
 136                 dev_err(dev->dev, "failed to allocate buffer object\n");
 137                 ret = -ENOMEM;
 138                 goto fail;
 139         }
 140
 141         fb = omap_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
 142         if (IS_ERR(fb)) {
 143                 dev_err(dev->dev, "failed to allocate fb\n");
 144                 /* note: if fb creation failed, we can't rely on fb destroy
 145                  * to unref the bo:
 146                  */
 147                 drm_gem_object_unreference_unlocked(fbdev->bo);
 148                 ret = PTR_ERR(fb);
 149                 goto fail;
 150         }
 151
 152         /* note: this keeps the bo pinned.. which is perhaps not ideal,
 153          * but is needed as long as we use fb_mmap() to mmap to userspace
 154          * (since this happens using fix.smem_start).  Possibly we could
 155          * implement our own mmap using GEM mmap support to avoid this
 156          * (non-tiled buffer doesn't need to be pinned for fbcon to write
 157          * to it).  Then we just need to be sure that we are able to re-
 158          * pin it in case of an opps.
 159          */
 160         ret = omap_gem_pin(fbdev->bo, &dma_addr);
 161         if (ret) {
 162                 dev_err(dev->dev, "could not pin framebuffer\n");
 163                 ret = -ENOMEM;
 164                 goto fail;
 165         }
 166
 167         mutex_lock(&dev->struct_mutex);
 168
 169         fbi = drm_fb_helper_alloc_fbi(helper);
 170         if (IS_ERR(fbi)) {
 171                 dev_err(dev->dev, "failed to allocate fb info\n");
 172                 ret = PTR_ERR(fbi);
 173                 goto fail_unlock;
 174         }
 175
 176         DBG("fbi=%p, dev=%p", fbi, dev);
 177
 178         fbdev->fb = fb;
 179         helper->fb = fb;
 180
 181         fbi->par = helper;
 182         fbi->fbops = &omap_fb_ops;
 183
 184         strcpy(fbi->fix.id, MODULE_NAME);
 185
 186         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth);
 187         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 188
 189         dev->mode_config.fb_base = dma_addr;
 190
 191         fbi->screen_base = omap_gem_vaddr(fbdev->bo);
 192         fbi->screen_size = fbdev->bo->size;
 193         fbi->fix.smem_start = dma_addr;
 194         fbi->fix.smem_len = fbdev->bo->size;
 195
 196         /* if we have DMM, then we can use it for scrolling by just
 197          * shuffling pages around in DMM rather than doing sw blit.
 198          */
 199         if (fbdev->ywrap_enabled) {
 200                 DRM_INFO("Enabling DMM ywrap scrolling\n");
 201                 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
 202                 fbi->fix.ywrapstep = 1;
 203         }
 204
 205
 206         DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 207         DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
 208
 209         mutex_unlock(&dev->struct_mutex);
 210
 211         return 0;
 212
 213 fail_unlock:
 214         mutex_unlock(&dev->struct_mutex);
 215 fail:
 216
 217         if (ret) {
 218                 if (fb)
 219                         drm_framebuffer_remove(fb);
 220         }
 221
 222         return ret;
 223 }
 224
 225 static const struct drm_fb_helper_funcs omap_fb_helper_funcs = {
 226         .fb_probe = omap_fbdev_create,
 227 };
 228
 229 static struct drm_fb_helper *get_fb(struct fb_info *fbi)
 230 {
 231         if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
 232                 /* these are not the fb's you're looking for */
 233                 return NULL;
 234         }
 235         return fbi->par;
 236 }
 237
 238 /* initialize fbdev helper */
 239 struct drm_fb_helper *omap_fbdev_init(struct drm_device *dev)
 240 {
 241         struct omap_drm_private *priv = dev->dev_private;
 242         struct omap_fbdev *fbdev = NULL;
 243         struct drm_fb_helper *helper;
 244         int ret = 0;
 245
 246         fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
 247         if (!fbdev)
 248                 goto fail;
 249
 250         INIT_WORK(&fbdev->work, pan_worker);
 251
 252         helper = &fbdev->base;
 253
 254         drm_fb_helper_prepare(dev, helper, &omap_fb_helper_funcs);
 255
 256         ret = drm_fb_helper_init(dev, helper, priv->num_connectors);
 257         if (ret) {
 258                 dev_err(dev->dev, "could not init fbdev: ret=%d\n", ret);
 259                 goto fail;
 260         }
 261
 262         ret = drm_fb_helper_single_add_all_connectors(helper);
 263         if (ret)
 264                 goto fini;
 265
 266         ret = drm_fb_helper_initial_config(helper, 32);
 267         if (ret)
 268                 goto fini;
 269
 270         priv->fbdev = helper;
 271
 272         return helper;
 273
 274 fini:
 275         drm_fb_helper_fini(helper);
 276 fail:
 277         kfree(fbdev);
 278
 279         dev_warn(dev->dev, "omap_fbdev_init failed\n");
 280         /* well, limp along without an fbdev.. maybe X11 will work? */
 281
 282         return NULL;
 283 }
 284
 285 void omap_fbdev_free(struct drm_device *dev)
 286 {
 287         struct omap_drm_private *priv = dev->dev_private;
 288         struct drm_fb_helper *helper = priv->fbdev;
 289         struct omap_fbdev *fbdev;
 290
 291         DBG();
 292
 293         drm_fb_helper_unregister_fbi(helper);
 294
 295         drm_fb_helper_fini(helper);
 296
 297         fbdev = to_omap_fbdev(priv->fbdev);
 298
 299         /* unpin the GEM object pinned in omap_fbdev_create() */
 300         omap_gem_unpin(fbdev->bo);
 301
 302         /* this will free the backing object */
 303         if (fbdev->fb)
 304                 drm_framebuffer_remove(fbdev->fb);
 305
 306         kfree(fbdev);
 307
 308         priv->fbdev = NULL;
 309 }