kernel/drivers/gpu/drm/omapdrm/omap_fbdev.c

   1 /*
   2  * drivers/gpu/drm/omapdrm/omap_fbdev.c
   3  *
   4  * Copyright (C) 2011 Texas Instruments
   5  * Author: Rob Clark <rob@ti.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published by
   9  * the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along with
  17  * this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <drm/drm_crtc.h>
  21 #include <drm/drm_fb_helper.h>
  22
  23 #include "omap_drv.h"
  24
  25 MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')");
  26 static bool ywrap_enabled = true;
  27 module_param_named(ywrap, ywrap_enabled, bool, 0644);
  28
  29 /*
  30  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
  31  */
  32
  33 #define to_omap_fbdev(x) container_of(x, struct omap_fbdev, base)
  34
  35 struct omap_fbdev {
  36         struct drm_fb_helper base;
  37         struct drm_framebuffer *fb;
  38         struct drm_gem_object *bo;
  39         bool ywrap_enabled;
  40
  41         /* for deferred dmm roll when getting called in atomic ctx */
  42         struct work_struct work;
  43 };
  44
  45 static struct drm_fb_helper *get_fb(struct fb_info *fbi);
  46
  47 static void pan_worker(struct work_struct *work)
  48 {
  49         struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
  50         struct fb_info *fbi = fbdev->base.fbdev;
  51         int npages;
  52
  53         /* DMM roll shifts in 4K pages: */
  54         npages = fbi->fix.line_length >> PAGE_SHIFT;
  55         omap_gem_roll(fbdev->bo, fbi->var.yoffset * npages);
  56 }
  57
  58 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var,
  59                 struct fb_info *fbi)
  60 {
  61         struct drm_fb_helper *helper = get_fb(fbi);
  62         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
  63
  64         if (!helper)
  65                 goto fallback;
  66
  67         if (!fbdev->ywrap_enabled)
  68                 goto fallback;
  69
  70         if (drm_can_sleep()) {
  71                 pan_worker(&fbdev->work);
  72         } else {
  73                 struct omap_drm_private *priv = helper->dev->dev_private;
  74                 queue_work(priv->wq, &fbdev->work);
  75         }
  76
  77         return 0;
  78
  79 fallback:
  80         return drm_fb_helper_pan_display(var, fbi);
  81 }
  82
  83 static struct fb_ops omap_fb_ops = {
  84         .owner = THIS_MODULE,
  85
  86         /* Note: to properly handle manual update displays, we wrap the
  87          * basic fbdev ops which write to the framebuffer
  88          */
  89         .fb_read = drm_fb_helper_sys_read,
  90         .fb_write = drm_fb_helper_sys_write,
  91         .fb_fillrect = drm_fb_helper_sys_fillrect,
  92         .fb_copyarea = drm_fb_helper_sys_copyarea,
  93         .fb_imageblit = drm_fb_helper_sys_imageblit,
  94
  95         .fb_check_var = drm_fb_helper_check_var,
  96         .fb_set_par = drm_fb_helper_set_par,
  97         .fb_pan_display = omap_fbdev_pan_display,
  98         .fb_blank = drm_fb_helper_blank,
  99         .fb_setcmap = drm_fb_helper_setcmap,
 100 };
 101
 102 static int omap_fbdev_create(struct drm_fb_helper *helper,
 103                 struct drm_fb_helper_surface_size *sizes)
 104 {
 105         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
 106         struct drm_device *dev = helper->dev;
 107         struct omap_drm_private *priv = dev->dev_private;
 108         struct drm_framebuffer *fb = NULL;
 109         union omap_gem_size gsize;
 110         struct fb_info *fbi = NULL;
 111         struct drm_mode_fb_cmd2 mode_cmd = {0};
 112         dma_addr_t paddr;
 113         int ret;
 114
 115         sizes->surface_bpp = 32;
 116         sizes->surface_depth = 24;
 117
 118         DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
 119                         sizes->surface_height, sizes->surface_bpp,
 120                         sizes->fb_width, sizes->fb_height);
 121
 122         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 123                         sizes->surface_depth);
 124
 125         mode_cmd.width = sizes->surface_width;
 126         mode_cmd.height = sizes->surface_height;
 127
 128         mode_cmd.pitches[0] = align_pitch(
 129                         mode_cmd.width * ((sizes->surface_bpp + 7) / 8),
 130                         mode_cmd.width, sizes->surface_bpp);
 131
 132         fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
 133         if (fbdev->ywrap_enabled) {
 134                 /* need to align pitch to page size if using DMM scrolling */
 135                 mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]);
 136         }
 137
 138         /* allocate backing bo */
 139         gsize = (union omap_gem_size){
 140                 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
 141         };
 142         DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
 143         fbdev->bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
 144         if (!fbdev->bo) {
 145                 dev_err(dev->dev, "failed to allocate buffer object\n");
 146                 ret = -ENOMEM;
 147                 goto fail;
 148         }
 149
 150         fb = omap_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
 151         if (IS_ERR(fb)) {
 152                 dev_err(dev->dev, "failed to allocate fb\n");
 153                 /* note: if fb creation failed, we can't rely on fb destroy
 154                  * to unref the bo:
 155                  */
 156                 drm_gem_object_unreference(fbdev->bo);
 157                 ret = PTR_ERR(fb);
 158                 goto fail;
 159         }
 160
 161         /* note: this keeps the bo pinned.. which is perhaps not ideal,
 162          * but is needed as long as we use fb_mmap() to mmap to userspace
 163          * (since this happens using fix.smem_start).  Possibly we could
 164          * implement our own mmap using GEM mmap support to avoid this
 165          * (non-tiled buffer doesn't need to be pinned for fbcon to write
 166          * to it).  Then we just need to be sure that we are able to re-
 167          * pin it in case of an opps.
 168          */
 169         ret = omap_gem_get_paddr(fbdev->bo, &paddr, true);
 170         if (ret) {
 171                 dev_err(dev->dev,
 172                         "could not map (paddr)!  Skipping framebuffer alloc\n");
 173                 ret = -ENOMEM;
 174                 goto fail;
 175         }
 176
 177         mutex_lock(&dev->struct_mutex);
 178
 179         fbi = drm_fb_helper_alloc_fbi(helper);
 180         if (IS_ERR(fbi)) {
 181                 dev_err(dev->dev, "failed to allocate fb info\n");
 182                 ret = PTR_ERR(fbi);
 183                 goto fail_unlock;
 184         }
 185
 186         DBG("fbi=%p, dev=%p", fbi, dev);
 187
 188         fbdev->fb = fb;
 189         helper->fb = fb;
 190
 191         fbi->par = helper;
 192         fbi->flags = FBINFO_DEFAULT;
 193         fbi->fbops = &omap_fb_ops;
 194
 195         strcpy(fbi->fix.id, MODULE_NAME);
 196
 197         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
 198         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 199
 200         dev->mode_config.fb_base = paddr;
 201
 202         fbi->screen_base = omap_gem_vaddr(fbdev->bo);
 203         fbi->screen_size = fbdev->bo->size;
 204         fbi->fix.smem_start = paddr;
 205         fbi->fix.smem_len = fbdev->bo->size;
 206
 207         /* if we have DMM, then we can use it for scrolling by just
 208          * shuffling pages around in DMM rather than doing sw blit.
 209          */
 210         if (fbdev->ywrap_enabled) {
 211                 DRM_INFO("Enabling DMM ywrap scrolling\n");
 212                 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
 213                 fbi->fix.ywrapstep = 1;
 214         }
 215
 216
 217         DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 218         DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
 219
 220         mutex_unlock(&dev->struct_mutex);
 221
 222         return 0;
 223
 224 fail_unlock:
 225         mutex_unlock(&dev->struct_mutex);
 226 fail:
 227
 228         if (ret) {
 229
 230                 drm_fb_helper_release_fbi(helper);
 231
 232                 if (fb) {
 233                         drm_framebuffer_unregister_private(fb);
 234                         drm_framebuffer_remove(fb);
 235                 }
 236         }
 237
 238         return ret;
 239 }
 240
 241 static const struct drm_fb_helper_funcs omap_fb_helper_funcs = {
 242         .fb_probe = omap_fbdev_create,
 243 };
 244
 245 static struct drm_fb_helper *get_fb(struct fb_info *fbi)
 246 {
 247         if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
 248                 /* these are not the fb's you're looking for */
 249                 return NULL;
 250         }
 251         return fbi->par;
 252 }
 253
 254 /* initialize fbdev helper */
 255 struct drm_fb_helper *omap_fbdev_init(struct drm_device *dev)
 256 {
 257         struct omap_drm_private *priv = dev->dev_private;
 258         struct omap_fbdev *fbdev = NULL;
 259         struct drm_fb_helper *helper;
 260         int ret = 0;
 261
 262         fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
 263         if (!fbdev)
 264                 goto fail;
 265
 266         INIT_WORK(&fbdev->work, pan_worker);
 267
 268         helper = &fbdev->base;
 269
 270         drm_fb_helper_prepare(dev, helper, &omap_fb_helper_funcs);
 271
 272         ret = drm_fb_helper_init(dev, helper,
 273                         priv->num_crtcs, priv->num_connectors);
 274         if (ret) {
 275                 dev_err(dev->dev, "could not init fbdev: ret=%d\n", ret);
 276                 goto fail;
 277         }
 278
 279         ret = drm_fb_helper_single_add_all_connectors(helper);
 280         if (ret)
 281                 goto fini;
 282
 283         /* disable all the possible outputs/crtcs before entering KMS mode */
 284         drm_helper_disable_unused_functions(dev);
 285
 286         ret = drm_fb_helper_initial_config(helper, 32);
 287         if (ret)
 288                 goto fini;
 289
 290         priv->fbdev = helper;
 291
 292         return helper;
 293
 294 fini:
 295         drm_fb_helper_fini(helper);
 296 fail:
 297         kfree(fbdev);
 298         return NULL;
 299 }
 300
 301 void omap_fbdev_free(struct drm_device *dev)
 302 {
 303         struct omap_drm_private *priv = dev->dev_private;
 304         struct drm_fb_helper *helper = priv->fbdev;
 305         struct omap_fbdev *fbdev;
 306
 307         DBG();
 308
 309         drm_fb_helper_unregister_fbi(helper);
 310         drm_fb_helper_release_fbi(helper);
 311
 312         drm_fb_helper_fini(helper);
 313
 314         fbdev = to_omap_fbdev(priv->fbdev);
 315
 316         /* release the ref taken in omap_fbdev_create() */
 317         omap_gem_put_paddr(fbdev->bo);
 318
 319         /* this will free the backing object */
 320         if (fbdev->fb) {
 321                 drm_framebuffer_unregister_private(fbdev->fb);
 322                 drm_framebuffer_remove(fbdev->fb);
 323         }
 324
 325         kfree(fbdev);
 326
 327         priv->fbdev = NULL;
 328 }