releases/2.6.34.9/drm-radeon-kms-handle-the-case-of-no-active-displays.patch

From e35136fa96eb52ed229aafa60ef1d48b93acb85d Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexdeucher@gmail.com>
Date: Mon, 2 Aug 2010 12:13:46 -0400
Subject: [PATCH] drm/radeon/kms: handle the case of no active displays
 properly in the bandwidth code

commit e06b14ee91a2ddefc9a67443a6cd8ee0fa800115 upstream.

Logic was:
if (mode0 && mode1)
else if (mode0)
else

Should be:
if (mode0 && mode1)
else if (mode0)
else if (mode1)

Otherwise we may end up calculating the priority regs with
unitialized values.

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=16492

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c
index 97e3002..6249cf7 100644
--- a/drivers/gpu/drm/radeon/rs690.c
+++ b/drivers/gpu/drm/radeon/rs690.c
@@ -400,7 +400,9 @@ void rs690_bandwidth_update(struct radeon_device *rdev)
 	struct drm_display_mode *mode1 = NULL;
 	struct rs690_watermark wm0;
 	struct rs690_watermark wm1;
-	u32 tmp, d1mode_priority_a_cnt, d2mode_priority_a_cnt;
+	u32 tmp;
+	u32 d1mode_priority_a_cnt = S_006548_D1MODE_PRIORITY_A_OFF(1);
+	u32 d2mode_priority_a_cnt = S_006548_D1MODE_PRIORITY_A_OFF(1);
 	fixed20_12 priority_mark02, priority_mark12, fill_rate;
 	fixed20_12 a, b;
 
@@ -497,10 +499,6 @@ void rs690_bandwidth_update(struct radeon_device *rdev)
 			d1mode_priority_a_cnt |= S_006548_D1MODE_PRIORITY_A_ALWAYS_ON(1);
 			d2mode_priority_a_cnt |= S_006D48_D2MODE_PRIORITY_A_ALWAYS_ON(1);
 		}
-		WREG32(R_006548_D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
-		WREG32(R_00654C_D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
-		WREG32(R_006D48_D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
-		WREG32(R_006D4C_D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 	} else if (mode0) {
 		if (rfixed_trunc(wm0.dbpp) > 64)
 			a.full = rfixed_mul(wm0.dbpp, wm0.num_line_pair);
@@ -530,13 +528,7 @@ void rs690_bandwidth_update(struct radeon_device *rdev)
 		d1mode_priority_a_cnt = rfixed_trunc(priority_mark02);
 		if (rdev->disp_priority == 2)
 			d1mode_priority_a_cnt |= S_006548_D1MODE_PRIORITY_A_ALWAYS_ON(1);
-		WREG32(R_006548_D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
-		WREG32(R_00654C_D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
-		WREG32(R_006D48_D2MODE_PRIORITY_A_CNT,
-			S_006D48_D2MODE_PRIORITY_A_OFF(1));
-		WREG32(R_006D4C_D2MODE_PRIORITY_B_CNT,
-			S_006D4C_D2MODE_PRIORITY_B_OFF(1));
-	} else {
+	} else if (mode1) {
 		if (rfixed_trunc(wm1.dbpp) > 64)
 			a.full = rfixed_mul(wm1.dbpp, wm1.num_line_pair);
 		else
@@ -565,13 +557,12 @@ void rs690_bandwidth_update(struct radeon_device *rdev)
 		d2mode_priority_a_cnt = rfixed_trunc(priority_mark12);
 		if (rdev->disp_priority == 2)
 			d2mode_priority_a_cnt |= S_006D48_D2MODE_PRIORITY_A_ALWAYS_ON(1);
-		WREG32(R_006548_D1MODE_PRIORITY_A_CNT,
-			S_006548_D1MODE_PRIORITY_A_OFF(1));
-		WREG32(R_00654C_D1MODE_PRIORITY_B_CNT,
-			S_00654C_D1MODE_PRIORITY_B_OFF(1));
-		WREG32(R_006D48_D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
-		WREG32(R_006D4C_D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 	}
+
+	WREG32(R_006548_D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
+	WREG32(R_00654C_D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
+	WREG32(R_006D48_D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
+	WREG32(R_006D4C_D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 }
 
 uint32_t rs690_mc_rreg(struct radeon_device *rdev, uint32_t reg)
diff --git a/drivers/gpu/drm/radeon/rv515.c b/drivers/gpu/drm/radeon/rv515.c
index 9035121..cf8f27f 100644
--- a/drivers/gpu/drm/radeon/rv515.c
+++ b/drivers/gpu/drm/radeon/rv515.c
@@ -1017,7 +1017,9 @@ void rv515_bandwidth_avivo_update(struct radeon_device *rdev)
 	struct drm_display_mode *mode1 = NULL;
 	struct rv515_watermark wm0;
 	struct rv515_watermark wm1;
-	u32 tmp, d1mode_priority_a_cnt, d2mode_priority_a_cnt;
+	u32 tmp;
+	u32 d1mode_priority_a_cnt = MODE_PRIORITY_OFF;
+	u32 d2mode_priority_a_cnt = MODE_PRIORITY_OFF;
 	fixed20_12 priority_mark02, priority_mark12, fill_rate;
 	fixed20_12 a, b;
 
@@ -1091,10 +1093,6 @@ void rv515_bandwidth_avivo_update(struct radeon_device *rdev)
 			d1mode_priority_a_cnt |= MODE_PRIORITY_ALWAYS_ON;
 			d2mode_priority_a_cnt |= MODE_PRIORITY_ALWAYS_ON;
 		}
-		WREG32(D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
-		WREG32(D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
-		WREG32(D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
-		WREG32(D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 	} else if (mode0) {
 		if (rfixed_trunc(wm0.dbpp) > 64)
 			a.full = rfixed_div(wm0.dbpp, wm0.num_line_pair);
@@ -1124,11 +1122,7 @@ void rv515_bandwidth_avivo_update(struct radeon_device *rdev)
 		d1mode_priority_a_cnt = rfixed_trunc(priority_mark02);
 		if (rdev->disp_priority == 2)
 			d1mode_priority_a_cnt |= MODE_PRIORITY_ALWAYS_ON;
-		WREG32(D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
-		WREG32(D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
-		WREG32(D2MODE_PRIORITY_A_CNT, MODE_PRIORITY_OFF);
-		WREG32(D2MODE_PRIORITY_B_CNT, MODE_PRIORITY_OFF);
-	} else {
+	} else if (mode1) {
 		if (rfixed_trunc(wm1.dbpp) > 64)
 			a.full = rfixed_div(wm1.dbpp, wm1.num_line_pair);
 		else
@@ -1157,11 +1151,12 @@ void rv515_bandwidth_avivo_update(struct radeon_device *rdev)
 		d2mode_priority_a_cnt = rfixed_trunc(priority_mark12);
 		if (rdev->disp_priority == 2)
 			d2mode_priority_a_cnt |= MODE_PRIORITY_ALWAYS_ON;
-		WREG32(D1MODE_PRIORITY_A_CNT, MODE_PRIORITY_OFF);
-		WREG32(D1MODE_PRIORITY_B_CNT, MODE_PRIORITY_OFF);
-		WREG32(D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
-		WREG32(D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 	}
+
+	WREG32(D1MODE_PRIORITY_A_CNT, d1mode_priority_a_cnt);
+	WREG32(D1MODE_PRIORITY_B_CNT, d1mode_priority_a_cnt);
+	WREG32(D2MODE_PRIORITY_A_CNT, d2mode_priority_a_cnt);
+	WREG32(D2MODE_PRIORITY_B_CNT, d2mode_priority_a_cnt);
 }
 
 void rv515_bandwidth_update(struct radeon_device *rdev)
-- 
1.7.4.4