[PATCH 5/9] drm/i915: Unlock PCH_PP_CONTROL always

From: Keith Packard
Date: Mon Sep 19 2011 - 18:23:25 EST


Avoid any question about locked registers by just writing the unlock
pattern with every write to the register.

Signed-off-by: Keith Packard <keithp@xxxxxxxxxx>
---
drivers/gpu/drm/i915/i915_reg.h | 1 +
drivers/gpu/drm/i915/intel_dp.c | 14 +++++++++++++-
2 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index b7fbb74..5596e8e 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3311,6 +3311,7 @@
#define PCH_PP_STATUS 0xc7200
#define PCH_PP_CONTROL 0xc7204
#define PANEL_UNLOCK_REGS (0xabcd << 16)
+#define PANEL_UNLOCK_MASK (0xffff << 16)
#define EDP_FORCE_VDD (1 << 3)
#define EDP_BLC_ENABLE (1 << 2)
#define PANEL_POWER_RESET (1 << 1)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 3b29a6f..a983d0f 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -840,6 +840,8 @@ static void ironlake_edp_panel_vdd_on(struct intel_dp *intel_dp)
msleep(dev_priv->panel_t3);

pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;
pp |= EDP_FORCE_VDD;
I915_WRITE(PCH_PP_CONTROL, pp);
POSTING_READ(PCH_PP_CONTROL);
@@ -852,6 +854,8 @@ static void ironlake_edp_panel_vdd_off(struct intel_dp *intel_dp)
u32 pp;

pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;
pp &= ~EDP_FORCE_VDD;
I915_WRITE(PCH_PP_CONTROL, pp);
POSTING_READ(PCH_PP_CONTROL);
@@ -871,13 +875,15 @@ static bool ironlake_edp_panel_on (struct intel_dp *intel_dp)
return true;

pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;

/* ILK workaround: disable reset around power sequence */
pp &= ~PANEL_POWER_RESET;
I915_WRITE(PCH_PP_CONTROL, pp);
POSTING_READ(PCH_PP_CONTROL);

- pp |= PANEL_UNLOCK_REGS | POWER_TARGET_ON;
+ pp |= POWER_TARGET_ON;
I915_WRITE(PCH_PP_CONTROL, pp);
POSTING_READ(PCH_PP_CONTROL);

@@ -900,6 +906,8 @@ static void ironlake_edp_panel_off (struct drm_device *dev)
PP_CYCLE_DELAY_ACTIVE | PP_SEQUENCE_STATE_MASK;

pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;

/* ILK workaround: disable reset around power sequence */
pp &= ~PANEL_POWER_RESET;
@@ -926,6 +934,8 @@ static void ironlake_edp_backlight_on (struct drm_device *dev)

DRM_DEBUG_KMS("\n");
pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;
pp |= EDP_BLC_ENABLE;
I915_WRITE(PCH_PP_CONTROL, pp);
}
@@ -937,6 +947,8 @@ static void ironlake_edp_backlight_off (struct drm_device *dev)

DRM_DEBUG_KMS("\n");
pp = I915_READ(PCH_PP_CONTROL);
+ pp &= ~PANEL_UNLOCK_MASK;
+ pp |= PANEL_UNLOCK_REGS;
pp &= ~EDP_BLC_ENABLE;
I915_WRITE(PCH_PP_CONTROL, pp);
}
--
1.7.6.3

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