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 "omap_drv.h"
  21
  22 #include "drm_crtc.h"
  23 #include "drm_fb_helper.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 void omap_fbdev_flush(struct fb_info *fbi, int x, int y, int w, int h);
  46 static struct drm_fb_helper *get_fb(struct fb_info *fbi);
  47
  48 static ssize_t omap_fbdev_write(struct fb_info *fbi, const char __user *buf,
  49                 size_t count, loff_t *ppos)
  50 {
  51         ssize_t res;
  52
  53         res = fb_sys_write(fbi, buf, count, ppos);
  54         omap_fbdev_flush(fbi, 0, 0, fbi->var.xres, fbi->var.yres);
  55
  56         return res;
  57 }
  58
  59 static void omap_fbdev_fillrect(struct fb_info *fbi,
  60                 const struct fb_fillrect *rect)
  61 {
  62         sys_fillrect(fbi, rect);
  63         omap_fbdev_flush(fbi, rect->dx, rect->dy, rect->width, rect->height);
  64 }
  65
  66 static void omap_fbdev_copyarea(struct fb_info *fbi,
  67                 const struct fb_copyarea *area)
  68 {
  69         sys_copyarea(fbi, area);
  70         omap_fbdev_flush(fbi, area->dx, area->dy, area->width, area->height);
  71 }
  72
  73 static void omap_fbdev_imageblit(struct fb_info *fbi,
  74                 const struct fb_image *image)
  75 {
  76         sys_imageblit(fbi, image);
  77         omap_fbdev_flush(fbi, image->dx, image->dy,
  78                                 image->width, image->height);
  79 }
  80
  81 static void pan_worker(struct work_struct *work)
  82 {
  83         struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
  84         struct fb_info *fbi = fbdev->base.fbdev;
  85         int npages;
  86
  87         /* DMM roll shifts in 4K pages: */
  88         npages = fbi->fix.line_length >> PAGE_SHIFT;
  89         omap_gem_roll(fbdev->bo, fbi->var.yoffset * npages);
  90 }
  91
  92 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var,
  93                 struct fb_info *fbi)
  94 {
  95         struct drm_fb_helper *helper = get_fb(fbi);
  96         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
  97
  98         if (!helper)
  99                 goto fallback;
 100
 101         if (!fbdev->ywrap_enabled)
 102                 goto fallback;
 103
 104         if (drm_can_sleep()) {
 105                 pan_worker(&fbdev->work);
 106         } else {
 107                 struct omap_drm_private *priv = helper->dev->dev_private;
 108                 queue_work(priv->wq, &fbdev->work);
 109         }
 110
 111         return 0;
 112
 113 fallback:
 114         return drm_fb_helper_pan_display(var, fbi);
 115 }
 116
 117 static struct fb_ops omap_fb_ops = {
 118         .owner = THIS_MODULE,
 119
 120         /* Note: to properly handle manual update displays, we wrap the
 121          * basic fbdev ops which write to the framebuffer
 122          */
 123         .fb_read = fb_sys_read,
 124         .fb_write = omap_fbdev_write,
 125         .fb_fillrect = omap_fbdev_fillrect,
 126         .fb_copyarea = omap_fbdev_copyarea,
 127         .fb_imageblit = omap_fbdev_imageblit,
 128
 129         .fb_check_var = drm_fb_helper_check_var,
 130         .fb_set_par = drm_fb_helper_set_par,
 131         .fb_pan_display = omap_fbdev_pan_display,
 132         .fb_blank = drm_fb_helper_blank,
 133         .fb_setcmap = drm_fb_helper_setcmap,
 134 };
 135
 136 static int omap_fbdev_create(struct drm_fb_helper *helper,
 137                 struct drm_fb_helper_surface_size *sizes)
 138 {
 139         struct omap_fbdev *fbdev = to_omap_fbdev(helper);
 140         struct drm_device *dev = helper->dev;
 141         struct omap_drm_private *priv = dev->dev_private;
 142         struct drm_framebuffer *fb = NULL;
 143         union omap_gem_size gsize;
 144         struct fb_info *fbi = NULL;
 145         struct drm_mode_fb_cmd2 mode_cmd = {0};
 146         dma_addr_t paddr;
 147         int ret;
 148
 149         /* only doing ARGB32 since this is what is needed to alpha-blend
 150          * with video overlays:
 151          */
 152         sizes->surface_bpp = 32;
 153         sizes->surface_depth = 32;
 154
 155         DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
 156                         sizes->surface_height, sizes->surface_bpp,
 157                         sizes->fb_width, sizes->fb_height);
 158
 159         mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
 160                         sizes->surface_depth);
 161
 162         mode_cmd.width = sizes->surface_width;
 163         mode_cmd.height = sizes->surface_height;
 164
 165         mode_cmd.pitches[0] = align_pitch(
 166                         mode_cmd.width * ((sizes->surface_bpp + 7) / 8),
 167                         mode_cmd.width, sizes->surface_bpp);
 168
 169         fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
 170         if (fbdev->ywrap_enabled) {
 171                 /* need to align pitch to page size if using DMM scrolling */
 172                 mode_cmd.pitches[0] = ALIGN(mode_cmd.pitches[0], PAGE_SIZE);
 173         }
 174
 175         /* allocate backing bo */
 176         gsize = (union omap_gem_size){
 177                 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
 178         };
 179         DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
 180         fbdev->bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
 181         if (!fbdev->bo) {
 182                 dev_err(dev->dev, "failed to allocate buffer object\n");
 183                 ret = -ENOMEM;
 184                 goto fail;
 185         }
 186
 187         fb = omap_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
 188         if (IS_ERR(fb)) {
 189                 dev_err(dev->dev, "failed to allocate fb\n");
 190                 /* note: if fb creation failed, we can't rely on fb destroy
 191                  * to unref the bo:
 192                  */
 193                 drm_gem_object_unreference(fbdev->bo);
 194                 ret = PTR_ERR(fb);
 195                 goto fail;
 196         }
 197
 198         /* note: this keeps the bo pinned.. which is perhaps not ideal,
 199          * but is needed as long as we use fb_mmap() to mmap to userspace
 200          * (since this happens using fix.smem_start).  Possibly we could
 201          * implement our own mmap using GEM mmap support to avoid this
 202          * (non-tiled buffer doesn't need to be pinned for fbcon to write
 203          * to it).  Then we just need to be sure that we are able to re-
 204          * pin it in case of an opps.
 205          */
 206         ret = omap_gem_get_paddr(fbdev->bo, &paddr, true);
 207         if (ret) {
 208                 dev_err(dev->dev,
 209                         "could not map (paddr)!  Skipping framebuffer alloc\n");
 210                 ret = -ENOMEM;
 211                 goto fail;
 212         }
 213
 214         mutex_lock(&dev->struct_mutex);
 215
 216         fbi = framebuffer_alloc(0, dev->dev);
 217         if (!fbi) {
 218                 dev_err(dev->dev, "failed to allocate fb info\n");
 219                 ret = -ENOMEM;
 220                 goto fail_unlock;
 221         }
 222
 223         DBG("fbi=%p, dev=%p", fbi, dev);
 224
 225         fbdev->fb = fb;
 226         helper->fb = fb;
 227         helper->fbdev = fbi;
 228
 229         fbi->par = helper;
 230         fbi->flags = FBINFO_DEFAULT;
 231         fbi->fbops = &omap_fb_ops;
 232
 233         strcpy(fbi->fix.id, MODULE_NAME);
 234
 235         ret = fb_alloc_cmap(&fbi->cmap, 256, 0);
 236         if (ret) {
 237                 ret = -ENOMEM;
 238                 goto fail_unlock;
 239         }
 240
 241         drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
 242         drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 243
 244         dev->mode_config.fb_base = paddr;
 245
 246         fbi->screen_base = omap_gem_vaddr(fbdev->bo);
 247         fbi->screen_size = fbdev->bo->size;
 248         fbi->fix.smem_start = paddr;
 249         fbi->fix.smem_len = fbdev->bo->size;
 250
 251         /* if we have DMM, then we can use it for scrolling by just
 252          * shuffling pages around in DMM rather than doing sw blit.
 253          */
 254         if (fbdev->ywrap_enabled) {
 255                 DRM_INFO("Enabling DMM ywrap scrolling\n");
 256                 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
 257                 fbi->fix.ywrapstep = 1;
 258         }
 259
 260
 261         DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 262         DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
 263
 264         mutex_unlock(&dev->struct_mutex);
 265
 266         return 0;
 267
 268 fail_unlock:
 269         mutex_unlock(&dev->struct_mutex);
 270 fail:
 271
 272         if (ret) {
 273                 if (fbi)
 274                         framebuffer_release(fbi);
 275                 if (fb) {
 276                         drm_framebuffer_unregister_private(fb);
 277                         drm_framebuffer_remove(fb);
 278                 }
 279         }
 280
 281         return ret;
 282 }
 283
 284 static struct drm_fb_helper_funcs omap_fb_helper_funcs = {
 285         .fb_probe = omap_fbdev_create,
 286 };
 287
 288 static struct drm_fb_helper *get_fb(struct fb_info *fbi)
 289 {
 290         if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
 291                 /* these are not the fb's you're looking for */
 292                 return NULL;
 293         }
 294         return fbi->par;
 295 }
 296
 297 /* flush an area of the framebuffer (in case of manual update display that
 298  * is not automatically flushed)
 299  */
 300 static void omap_fbdev_flush(struct fb_info *fbi, int x, int y, int w, int h)
 301 {
 302         struct drm_fb_helper *helper = get_fb(fbi);
 303
 304         if (!helper)
 305                 return;
 306
 307         VERB("flush fbdev: %d,%d %dx%d, fbi=%p", x, y, w, h, fbi);
 308
 309         omap_framebuffer_flush(helper->fb, x, y, w, h);
 310 }
 311
 312 /* initialize fbdev helper */
 313 struct drm_fb_helper *omap_fbdev_init(struct drm_device *dev)
 314 {
 315         struct omap_drm_private *priv = dev->dev_private;
 316         struct omap_fbdev *fbdev = NULL;
 317         struct drm_fb_helper *helper;
 318         int ret = 0;
 319
 320         fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
 321         if (!fbdev)
 322                 goto fail;
 323
 324         INIT_WORK(&fbdev->work, pan_worker);
 325
 326         helper = &fbdev->base;
 327
 328         helper->funcs = &omap_fb_helper_funcs;
 329
 330         ret = drm_fb_helper_init(dev, helper,
 331                         priv->num_crtcs, priv->num_connectors);
 332         if (ret) {
 333                 dev_err(dev->dev, "could not init fbdev: ret=%d\n", ret);
 334                 goto fail;
 335         }
 336
 337         drm_fb_helper_single_add_all_connectors(helper);
 338
 339         /* disable all the possible outputs/crtcs before entering KMS mode */
 340         drm_helper_disable_unused_functions(dev);
 341
 342         drm_fb_helper_initial_config(helper, 32);
 343
 344         priv->fbdev = helper;
 345
 346         return helper;
 347
 348 fail:
 349         kfree(fbdev);
 350         return NULL;
 351 }
 352
 353 void omap_fbdev_free(struct drm_device *dev)
 354 {
 355         struct omap_drm_private *priv = dev->dev_private;
 356         struct drm_fb_helper *helper = priv->fbdev;
 357         struct omap_fbdev *fbdev;
 358         struct fb_info *fbi;
 359
 360         DBG();
 361
 362         fbi = helper->fbdev;
 363
 364         /* only cleanup framebuffer if it is present */
 365         if (fbi) {
 366                 unregister_framebuffer(fbi);
 367                 framebuffer_release(fbi);
 368         }
 369
 370         drm_fb_helper_fini(helper);
 371
 372         fbdev = to_omap_fbdev(priv->fbdev);
 373
 374         /* release the ref taken in omap_fbdev_create() */
 375         omap_gem_put_paddr(fbdev->bo);
 376
 377         /* this will free the backing object */
 378         if (fbdev->fb) {
 379                 drm_framebuffer_unregister_private(fbdev->fb);
 380                 drm_framebuffer_remove(fbdev->fb);
 381         }
 382
 383         kfree(fbdev);
 384
 385         priv->fbdev = NULL;
 386 }