[Maverick] [PATCH 1/1] (pre-stable) drm/i915: don't enable self-refresh on Ironlake

[Leann Ogasawara]

Hi All,

The following upstream patch resolves a screen corruption issue after
unplugging an external monitor attached to the VGA port, see LP Bug
629711.  The patch is included in 2.6.36-rc4 and has been Cc'd to
upstream stable.  The launchpad bug reporter has also confirmed this
patch resolves the issue.  Please consider applying as a pre-stable
patch to Maverick.

Thanks,
Leann     

>From ef69f8c9824106309a1c894bb5fe2a7cea81c4bb Mon Sep 17 00:00:00 2001
From: Jesse Barnes <jbarnes at virtuousgeek.org>
Date: Thu, 9 Sep 2010 11:58:02 -0700
Subject: [PATCH] (pre-stable) drm/i915: don't enable self-refresh on Ironlake

BugLink: http://bugs.launchpad.net/bugs/629711

We don't know how to enable it safely, especially as outputs turn on and
off.  When disabling LP1 we also need to make sure LP2 and 3 are already
disabled.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29173
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29082
Reported-by: Chris Lord <chris at linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
Tested-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: stable at kernel.org
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
(cherry picked from commit dd8849c8f59ec1cee4809a0c5e603e045abe860e)

Signed-off-by: Leann Ogasawara <leann.ogasawara at canonical.com>
---
 drivers/gpu/drm/i915/i915_reg.h      |    8 ++++++++
 drivers/gpu/drm/i915/intel_display.c |    6 ++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index cf41c67..f6dda38 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2199,9 +2199,17 @@
 #define  WM1_LP_SR_EN		(1<<31)
 #define  WM1_LP_LATENCY_SHIFT	24
 #define  WM1_LP_LATENCY_MASK	(0x7f<<24)
+#define  WM1_LP_FBC_LP1_MASK	(0xf<<20)
+#define  WM1_LP_FBC_LP1_SHIFT	20
 #define  WM1_LP_SR_MASK		(0x1ff<<8)
 #define  WM1_LP_SR_SHIFT	8
 #define  WM1_LP_CURSOR_MASK	(0x3f)
+#define WM2_LP_ILK		0x4510c
+#define  WM2_LP_EN		(1<<31)
+#define WM3_LP_ILK		0x45110
+#define  WM3_LP_EN		(1<<31)
+#define WM1S_LP_ILK		0x45120
+#define  WM1S_LP_EN		(1<<31)
 
 /* Memory latency timer register */
 #define MLTR_ILK		0x11222
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 48ad60b..9a00dc4 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3176,8 +3176,7 @@ static void ironlake_update_wm(struct drm_device *dev,  int planea_clock,
 		reg_value = I915_READ(WM1_LP_ILK);
 		reg_value &= ~(WM1_LP_LATENCY_MASK | WM1_LP_SR_MASK |
 			       WM1_LP_CURSOR_MASK);
-		reg_value |= WM1_LP_SR_EN |
-			     (ilk_sr_latency << WM1_LP_LATENCY_SHIFT) |
+		reg_value |= (ilk_sr_latency << WM1_LP_LATENCY_SHIFT) |
 			     (sr_wm << WM1_LP_SR_SHIFT) | cursor_wm;
 
 		I915_WRITE(WM1_LP_ILK, reg_value);
@@ -5395,6 +5394,9 @@ void intel_init_clock_gating(struct drm_device *dev)
 			I915_WRITE(DISP_ARB_CTL,
 					(I915_READ(DISP_ARB_CTL) |
 						DISP_FBC_WM_DIS));
+		I915_WRITE(WM3_LP_ILK, 0);
+		I915_WRITE(WM2_LP_ILK, 0);
+		I915_WRITE(WM1_LP_ILK, 0);
 		}
 		return;
 	} else if (IS_G4X(dev)) {
-- 
1.7.1