diff mbox

[2/4] drm/i915: preserve swizzle settings if necessary v4

Message ID 1412884665-16766-2-git-send-email-jbarnes@virtuousgeek.org (mailing list archive)
State New, archived
Headers show

Commit Message

Jesse Barnes Oct. 9, 2014, 7:57 p.m. UTC
Some machines (like MBAs) might use a tiled framebuffer but not enable
display swizzling at boot time.  We want to preserve that configuration
if possible to prevent a boot time mode set.  On IVB+ it shouldn't
affect performance anyway since the memory controller does internal
swizzling anyway.

For most other configs we'll be able to enable swizzling at boot time,
since the initial framebuffer won't be tiled, thus we won't see any
corruption when we enable it.

v2: preserve swizzling if BIOS had it set (Daniel)
v3: preserve swizzling only if we inherited a tiled framebuffer (Daniel)
    check display swizzle setting in detect_bit_6_swizzle (Daniel)
    use gen6 as cutoff point (Daniel)
v4: fixup swizzle preserve again, had wrong init order (Daniel)

Reported-by: Kristian Høgsberg <hoegsberg@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/gpu/drm/i915/i915_drv.h        |  2 ++
 drivers/gpu/drm/i915/i915_gem_tiling.c | 41 +++++++++++++++++++++-------------
 drivers/gpu/drm/i915/intel_display.c   |  4 ++++
 3 files changed, 32 insertions(+), 15 deletions(-)

Comments

Daniel Vetter Oct. 21, 2014, 2:49 p.m. UTC | #1
On Thu, Oct 09, 2014 at 12:57:43PM -0700, Jesse Barnes wrote:
> Some machines (like MBAs) might use a tiled framebuffer but not enable
> display swizzling at boot time.  We want to preserve that configuration
> if possible to prevent a boot time mode set.  On IVB+ it shouldn't
> affect performance anyway since the memory controller does internal
> swizzling anyway.
> 
> For most other configs we'll be able to enable swizzling at boot time,
> since the initial framebuffer won't be tiled, thus we won't see any
> corruption when we enable it.
> 
> v2: preserve swizzling if BIOS had it set (Daniel)
> v3: preserve swizzling only if we inherited a tiled framebuffer (Daniel)
>     check display swizzle setting in detect_bit_6_swizzle (Daniel)
>     use gen6 as cutoff point (Daniel)
> v4: fixup swizzle preserve again, had wrong init order (Daniel)
> 
> Reported-by: Kristian Høgsberg <hoegsberg@gmail.com>
> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

lgtm. Queued for -next, thanks for the patch.
-Daniel
Jesse Barnes Oct. 30, 2014, 9:25 p.m. UTC | #2
On Tue, 21 Oct 2014 16:49:12 +0200
Daniel Vetter <daniel@ffwll.ch> wrote:

> On Thu, Oct 09, 2014 at 12:57:43PM -0700, Jesse Barnes wrote:
> > Some machines (like MBAs) might use a tiled framebuffer but not
> > enable display swizzling at boot time.  We want to preserve that
> > configuration if possible to prevent a boot time mode set.  On IVB+
> > it shouldn't affect performance anyway since the memory controller
> > does internal swizzling anyway.
> > 
> > For most other configs we'll be able to enable swizzling at boot
> > time, since the initial framebuffer won't be tiled, thus we won't
> > see any corruption when we enable it.
> > 
> > v2: preserve swizzling if BIOS had it set (Daniel)
> > v3: preserve swizzling only if we inherited a tiled framebuffer
> > (Daniel) check display swizzle setting in detect_bit_6_swizzle
> > (Daniel) use gen6 as cutoff point (Daniel)
> > v4: fixup swizzle preserve again, had wrong init order (Daniel)
> > 
> > Reported-by: Kristian Høgsberg <hoegsberg@gmail.com>
> > Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
> 
> lgtm. Queued for -next, thanks for the patch.

Can you pick up the SSC one too (earlier in this thread)?  I applied
Jani's requested change which should address your concerns about the
BIOS and kernel disagreeing.

I'll ping Kristian again about the not-quite-preferred mode on his MBA.

Thanks,
Jesse
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1e476b5..6bcc754 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1527,6 +1527,8 @@  struct drm_i915_private {
 	struct intel_opregion opregion;
 	struct intel_vbt_data vbt;
 
+	bool preserve_bios_swizzle;
+
 	/* overlay */
 	struct intel_overlay *overlay;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index 2cefb59..d1e7a3e 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -102,22 +102,33 @@  i915_gem_detect_bit_6_swizzle(struct drm_device *dev)
 		swizzle_x = I915_BIT_6_SWIZZLE_NONE;
 		swizzle_y = I915_BIT_6_SWIZZLE_NONE;
 	} else if (INTEL_INFO(dev)->gen >= 6) {
-		uint32_t dimm_c0, dimm_c1;
-		dimm_c0 = I915_READ(MAD_DIMM_C0);
-		dimm_c1 = I915_READ(MAD_DIMM_C1);
-		dimm_c0 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
-		dimm_c1 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
-		/* Enable swizzling when the channels are populated with
-		 * identically sized dimms. We don't need to check the 3rd
-		 * channel because no cpu with gpu attached ships in that
-		 * configuration. Also, swizzling only makes sense for 2
-		 * channels anyway. */
-		if (dimm_c0 == dimm_c1) {
-			swizzle_x = I915_BIT_6_SWIZZLE_9_10;
-			swizzle_y = I915_BIT_6_SWIZZLE_9;
+		if (dev_priv->preserve_bios_swizzle) {
+			if (I915_READ(DISP_ARB_CTL) &
+			    DISP_TILE_SURFACE_SWIZZLING) {
+				swizzle_x = I915_BIT_6_SWIZZLE_9_10;
+				swizzle_y = I915_BIT_6_SWIZZLE_9;
+			} else {
+				swizzle_x = I915_BIT_6_SWIZZLE_NONE;
+				swizzle_y = I915_BIT_6_SWIZZLE_NONE;
+			}
 		} else {
-			swizzle_x = I915_BIT_6_SWIZZLE_NONE;
-			swizzle_y = I915_BIT_6_SWIZZLE_NONE;
+			uint32_t dimm_c0, dimm_c1;
+			dimm_c0 = I915_READ(MAD_DIMM_C0);
+			dimm_c1 = I915_READ(MAD_DIMM_C1);
+			dimm_c0 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
+			dimm_c1 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
+			/* Enable swizzling when the channels are populated
+			 * with identically sized dimms. We don't need to check
+			 * the 3rd channel because no cpu with gpu attached
+			 * ships in that configuration. Also, swizzling only
+			 * makes sense for 2 channels anyway. */
+			if (dimm_c0 == dimm_c1) {
+				swizzle_x = I915_BIT_6_SWIZZLE_9_10;
+				swizzle_y = I915_BIT_6_SWIZZLE_9;
+			} else {
+				swizzle_x = I915_BIT_6_SWIZZLE_NONE;
+				swizzle_y = I915_BIT_6_SWIZZLE_NONE;
+			}
 		}
 	} else if (IS_GEN5(dev)) {
 		/* On Ironlake whatever DRAM config, GPU always do
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3823135..1d0425d 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2361,6 +2361,7 @@  static void intel_find_plane_obj(struct intel_crtc *intel_crtc,
 				 struct intel_plane_config *plane_config)
 {
 	struct drm_device *dev = intel_crtc->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_crtc *c;
 	struct intel_crtc *i;
 	struct drm_i915_gem_object *obj;
@@ -2392,6 +2393,9 @@  static void intel_find_plane_obj(struct intel_crtc *intel_crtc,
 			continue;
 
 		if (i915_gem_obj_ggtt_offset(obj) == plane_config->base) {
+			if (obj->tiling_mode != I915_TILING_NONE)
+				dev_priv->preserve_bios_swizzle = true;
+
 			drm_framebuffer_reference(c->primary->fb);
 			intel_crtc->base.primary->fb = c->primary->fb;
 			obj->frontbuffer_bits |= INTEL_FRONTBUFFER_PRIMARY(intel_crtc->pipe);