[PATCH 1/1] i915: Save/restore MCHBAR_RENDER_STANDBY on GM965/GM45

[Andy Whitcroft]

commit 881ee9889c8b98671c5491e43666bf5d4f78a180 upstream

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>
Signed-off-by: Eric Anholt <eric at anholt.net>
Signed-off-by: Dave Airlie <airlied at linux.ie>
Signed-off-by: Andy Whitcroft <apw at canonical.com>
---
 drivers/gpu/drm/i915/i915_drv.c |    9 +++++++++
 drivers/gpu/drm/i915/i915_drv.h |    4 ++++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 93aed1c..6cb2b13 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -256,6 +256,10 @@ static int i915_suspend(struct drm_device *dev, pm_message_t state)
 	pci_save_state(dev->pdev);
 	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);
 
@@ -393,6 +397,11 @@ static int i915_resume(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 */
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index d7326d9..ff0db6a 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -120,6 +120,7 @@ typedef struct drm_i915_private {
 	u32 saveDSPACNTR;
 	u32 saveDSPBCNTR;
 	u32 saveDSPARB;
+	u32 saveRENDERSTANDBY;
 	u32 savePIPEACONF;
 	u32 savePIPEBCONF;
 	u32 savePIPEASRC;
@@ -1060,6 +1061,9 @@ extern int i915_wait_ring(struct drm_device * dev, int n, const char *caller);
 # define VGA_2X_MODE				(1 << 30)
 # define VGA_PIPE_B_SELECT			(1 << 29)
 
+/** GM965 GM45 render standby register */
+#define MCHBAR_RENDER_STANDBY	0x111B8
+
 /*
  * Some BIOS scratch area registers.  The 845 (and 830?) store the amount
  * of video memory available to the BIOS in SWF1.
-- 
1.6.0.4.911.gc990