[Intel-gfx] [PATCH] [drm/i915] Save/restore MCHBAR_RENDER_STANDBY on GM965/GM45

[Keith Packard]

This register is set by the 2D driver to prevent lockups, and so it needs to
be preserved across suspend/resume too. This makes my X200s work.

Signed-off-by: Keith Packard <keithp at keithp.com>
---
 drivers/gpu/drm/i915/i915_drv.h     |    1 +
 drivers/gpu/drm/i915/i915_reg.h     |    3 +++
 drivers/gpu/drm/i915/i915_suspend.c |    9 +++++++++
 3 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 9e19d38..2dfd4ac 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -157,6 +157,7 @@ typedef struct drm_i915_private {
 	u32 saveDSPACNTR;
 	u32 saveDSPBCNTR;
 	u32 saveDSPARB;
+	u32 saveRENDERSTANDBY;
 	u32 savePIPEACONF;
 	u32 savePIPEBCONF;
 	u32 savePIPEASRC;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 5c2d9f2..0e476eb 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -527,6 +527,9 @@
 #define C0DRB3			0x10206
 #define C1DRB3			0x10606
 
+/** GM965 GM45 render standby register */
+#define MCHBAR_RENDER_STANDBY	0x111B8
+
 /*
  * Overlay regs
  */
diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c
index 603fe74..5ddc6e5 100644
--- a/drivers/gpu/drm/i915/i915_suspend.c
+++ b/drivers/gpu/drm/i915/i915_suspend.c
@@ -240,6 +240,10 @@ int i915_save_state(struct drm_device *dev)
 
 	pci_read_config_byte(dev->pdev, LBB, &dev_priv->saveLBB);
 
+	/* Render Standby */
+	if (IS_I965G(dev) && IS_MOBILE(dev))
+		dev_priv->saveRENDERSTANDBY = I915_READ(MCHBAR_RENDER_STANDBY);
+
 	/* Display arbitration control */
 	dev_priv->saveDSPARB = I915_READ(DSPARB);
 
@@ -365,6 +369,11 @@ int i915_restore_state(struct drm_device *dev)
 
 	pci_write_config_byte(dev->pdev, LBB, dev_priv->saveLBB);
 
+	/* Render Standby */
+	if (IS_I965G(dev) && IS_MOBILE(dev))
+		I915_WRITE(MCHBAR_RENDER_STANDBY, dev_priv->saveRENDERSTANDBY);
+
+	/* Display arbitration */
 	I915_WRITE(DSPARB, dev_priv->saveDSPARB);
 
 	/* Pipe & plane A info */
-- 
1.5.6.5