drm/gma500: Remove GTT roll support

GTT roll support was used to accelerate fb panning on some machines.
Unfortunately this never worked properly with multiple monitors and
caused issues on others where the framebuffer wouldn't fit in stolen
memory. Let's remove it!

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201028143608.1284-1-patrik.r.jakobsson@gmail.com

1 files changed, 2 insertions, 50 deletions

diff --git a/drivers/gpu/drm/gma500/gtt.c b/drivers/gpu/drm/gma500/gtt.c
index 9278bcfad1bf..d246b1f70366 100644
--- a/drivers/gpu/drm/gma500/gtt.c
+++ b/drivers/gpu/drm/gma500/gtt.c
@@ -96,16 +96,12 @@ static int psb_gtt_insert(struct drm_device *dev, struct gtt_range *r,
 	}
 
 	/* Write our page entries into the GTT itself */
-	for (i = r->roll; i < r->npage; i++) {
-		pte = psb_gtt_mask_pte(page_to_pfn(r->pages[i]),
-				       PSB_MMU_CACHED_MEMORY);
-		iowrite32(pte, gtt_slot++);
-	}
-	for (i = 0; i < r->roll; i++) {
+	for (i = 0; i < r->npage; i++) {
 		pte = psb_gtt_mask_pte(page_to_pfn(r->pages[i]),
 				       PSB_MMU_CACHED_MEMORY);
 		iowrite32(pte, gtt_slot++);
 	}
+
 	/* Make sure all the entries are set before we return */
 	ioread32(gtt_slot - 1);
 
@@ -141,49 +137,6 @@ static void psb_gtt_remove(struct drm_device *dev, struct gtt_range *r)
 }
 
 /**
- *	psb_gtt_roll	-	set scrolling position
- *	@dev: our DRM device
- *	@r: the gtt mapping we are using
- *	@roll: roll offset
- *
- *	Roll an existing pinned mapping by moving the pages through the GTT.
- *	This allows us to implement hardware scrolling on the consoles without
- *	a 2D engine
- */
-void psb_gtt_roll(struct drm_device *dev, struct gtt_range *r, int roll)
-{
-	u32 __iomem *gtt_slot;
-	u32 pte;
-	int i;
-
-	if (roll >= r->npage) {
-		WARN_ON(1);
-		return;
-	}
-
-	r->roll = roll;
-
-	/* Not currently in the GTT - no worry we will write the mapping at
-	   the right position when it gets pinned */
-	if (!r->stolen && !r->in_gart)
-		return;
-
-	gtt_slot = psb_gtt_entry(dev, r);
-
-	for (i = r->roll; i < r->npage; i++) {
-		pte = psb_gtt_mask_pte(page_to_pfn(r->pages[i]),
-				       PSB_MMU_CACHED_MEMORY);
-		iowrite32(pte, gtt_slot++);
-	}
-	for (i = 0; i < r->roll; i++) {
-		pte = psb_gtt_mask_pte(page_to_pfn(r->pages[i]),
-				       PSB_MMU_CACHED_MEMORY);
-		iowrite32(pte, gtt_slot++);
-	}
-	ioread32(gtt_slot - 1);
-}
-
-/**
  *	psb_gtt_attach_pages	-	attach and pin GEM pages
  *	@gt: the gtt range
  *
@@ -346,7 +299,6 @@ struct gtt_range *psb_gtt_alloc_range(struct drm_device *dev, int len,
 	gt->resource.name = name;
 	gt->stolen = backed;
 	gt->in_gart = backed;
-	gt->roll = 0;
 	/* Ensure this is set for non GEM objects */
 	gt->gem.dev = dev;
 	ret = allocate_resource(dev_priv->gtt_mem, &gt->resource,