drm/cirrus: deal with bo reserve fail in dirty update path

[deliverable/linux.git] / drivers / gpu / drm / cirrus / cirrus_fbdev.c

diff --git a/drivers/gpu/drm/cirrus/cirrus_fbdev.c b/drivers/gpu/drm/cirrus/cirrus_fbdev.c
index e25afccaf85bd62feb4aae4d5dfab42d49c9ed4d..3541b567bbd8dffa9cb8d3e6d4c552ef06f09f21 100644 (file)
--- a/drivers/gpu/drm/cirrus/cirrus_fbdev.c
+++ b/drivers/gpu/drm/cirrus/cirrus_fbdev.c
@@ -27,16 +27,51 @@ static void cirrus_dirty_update(struct cirrus_fbdev *afbdev,
        int bpp = (afbdev->gfb.base.bits_per_pixel + 7)/8;
        int ret;
        bool unmap = false;
+       bool store_for_later = false;
+       int x2, y2;
+       unsigned long flags;
 
        obj = afbdev->gfb.obj;
        bo = gem_to_cirrus_bo(obj);
 
+       /*
+        * try and reserve the BO, if we fail with busy
+        * then the BO is being moved and we should
+        * store up the damage until later.
+        */
        ret = cirrus_bo_reserve(bo, true);
        if (ret) {
-               DRM_ERROR("failed to reserve fb bo\n");
+               if (ret != -EBUSY)
+                       return;
+               store_for_later = true;
+       }
+
+       x2 = x + width - 1;
+       y2 = y + height - 1;
+       spin_lock_irqsave(&afbdev->dirty_lock, flags);
+
+       if (afbdev->y1 < y)
+               y = afbdev->y1;
+       if (afbdev->y2 > y2)
+               y2 = afbdev->y2;
+       if (afbdev->x1 < x)
+               x = afbdev->x1;
+       if (afbdev->x2 > x2)
+               x2 = afbdev->x2;
+
+       if (store_for_later) {
+               afbdev->x1 = x;
+               afbdev->x2 = x2;
+               afbdev->y1 = y;
+               afbdev->y2 = y2;
+               spin_unlock_irqrestore(&afbdev->dirty_lock, flags);
                return;
        }
 
+       afbdev->x1 = afbdev->y1 = INT_MAX;
+       afbdev->x2 = afbdev->y2 = 0;
+       spin_unlock_irqrestore(&afbdev->dirty_lock, flags);
+
        if (!bo->kmap.virtual) {
                ret = ttm_bo_kmap(&bo->bo, 0, bo->bo.num_pages, &bo->kmap);
                if (ret) {
@@ -268,6 +303,7 @@ int cirrus_fbdev_init(struct cirrus_device *cdev)
 
        cdev->mode_info.gfbdev = gfbdev;
        gfbdev->helper.funcs = &cirrus_fb_helper_funcs;
+       spin_lock_init(&gfbdev->dirty_lock);
 
        ret = drm_fb_helper_init(cdev->dev, &gfbdev->helper,
                                 cdev->num_crtc, CIRRUSFB_CONN_LIMIT);