Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next

Daniel writes:

"- Regression fixer for an OOPS at boot when i915.ko is built-in and
  CONFIG_PM=n, introduce in 3.5 (patch from Hunt Xu)
- Regression fixer for occlusion query failures, the required w/a wasn't
  applied in all cases (thanks to Eric for tracking this on down).
- dmar vs. dma_buf imprt fix (Dave Airlie)
- 2 patches to fight down forcewake issues on snb. This is the stuff I've
  talked about 2 weeks ago already, it's a minefield. Investigation still
  going on, but afaict this is the best we have for now.
- a few minor things to keep coverty&compiler happy (Alan, Davendra,
  Stéphane)
- tons of hsw pci ids - this one is a bit late because internal approval
  sometimes takes a while, but ppl in charge finally agreed that world+dog
  already knows about ult and crw haswell variants ;-)

Wrt regressions I'm aware of:
- the power regression due to semaphores=1. Ben is running around with a
  killawatt, unfortunately we have a hard time reproducing this one. And
  this /shouldn't/ increase power usage. Ben has turned up a few odds bits
  though already.
- the lvds fix in 3.6-rc1 broke a backlight after lid close/open (but can
  be resurrected with a modeset cycle). I guess we anger the bios - I'm
  still looking into this one.
- gmbus broke edid reading on an odd-ball monitor, we need to fall-back.
  Due to vacation (both mine&the reporter's) this is stalling for a final
  patch and a tested-by on it. But issue is fully diagnosed."

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: correctly order the ring init sequence
  drm/i915: add more Haswell PCI IDs
  drm/i915: make rc6 in sysfs functions conditional
  drm/i915: Workaround hang with BSD and forcewake on SandyBridge
  drm/i915: Make intel_panel_get_backlight static.
  i915: don't map imported dma-bufs for dmar.
  drm/i915: remove unused variable
  drm/i915: Don't forget to apply SNB PIPE_CONTROL GTT workaround.
  drm/i915: fix forcewake related hangs on snb
  i915: Remove silly test
  i915: fix error path leak in intel_sdvo_write_cmd
  vlv: it might be wise if we initialised the flag value...

drivers/char/agp/intel-agp.h

@@ -242,13 +242,42 @@
 #define PCI_DEVICE_ID_INTEL_HASWELL_HB			0x0400 /* Desktop */
 #define PCI_DEVICE_ID_INTEL_HASWELL_D_GT1_IG		0x0402
 #define PCI_DEVICE_ID_INTEL_HASWELL_D_GT2_IG		0x0412
+#define PCI_DEVICE_ID_INTEL_HASWELL_D_GT2_PLUS_IG	0x0422
 #define PCI_DEVICE_ID_INTEL_HASWELL_M_HB		0x0404 /* Mobile */
 #define PCI_DEVICE_ID_INTEL_HASWELL_M_GT1_IG		0x0406
 #define PCI_DEVICE_ID_INTEL_HASWELL_M_GT2_IG		0x0416
+#define PCI_DEVICE_ID_INTEL_HASWELL_M_GT2_PLUS_IG	0x0426
 #define PCI_DEVICE_ID_INTEL_HASWELL_S_HB		0x0408 /* Server */
 #define PCI_DEVICE_ID_INTEL_HASWELL_S_GT1_IG		0x040a
 #define PCI_DEVICE_ID_INTEL_HASWELL_S_GT2_IG		0x041a
-#define PCI_DEVICE_ID_INTEL_HASWELL_SDV		0x0c16 /* SDV */
+#define PCI_DEVICE_ID_INTEL_HASWELL_S_GT2_PLUS_IG	0x042a
 #define PCI_DEVICE_ID_INTEL_HASWELL_E_HB		0x0c04
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT1_IG	0x0C02
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT2_IG	0x0C12
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT2_PLUS_IG	0x0C22
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT1_IG	0x0C06
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT2_IG	0x0C16
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT2_PLUS_IG	0x0C26
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT1_IG	0x0C0A
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT2_IG	0x0C1A
+#define PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT2_PLUS_IG	0x0C2A
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT1_IG	0x0A02
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT2_IG	0x0A12
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT2_PLUS_IG	0x0A22
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT1_IG	0x0A06
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT2_IG	0x0A16
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT2_PLUS_IG	0x0A26
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT1_IG	0x0A0A
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT2_IG	0x0A1A
+#define PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT2_PLUS_IG	0x0A2A
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT1_IG	0x0D12
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT2_IG	0x0D22
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT2_PLUS_IG	0x0D32
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT1_IG	0x0D16
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT2_IG	0x0D26
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT2_PLUS_IG	0x0D36
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT1_IG	0x0D1A
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT2_IG	0x0D2A
+#define PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT2_PLUS_IG	0x0D3A
 
 #endif

drivers/char/agp/intel-gtt.c

@@ -1502,15 +1502,73 @@ static const struct intel_gtt_driver_description {
 	    "Haswell", &sandybridge_gtt_driver },
 	{ PCI_DEVICE_ID_INTEL_HASWELL_D_GT2_IG,
 	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_D_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
 	{ PCI_DEVICE_ID_INTEL_HASWELL_M_GT1_IG,
 	    "Haswell", &sandybridge_gtt_driver },
 	{ PCI_DEVICE_ID_INTEL_HASWELL_M_GT2_IG,
 	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_M_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
 	{ PCI_DEVICE_ID_INTEL_HASWELL_S_GT1_IG,
 	    "Haswell", &sandybridge_gtt_driver },
 	{ PCI_DEVICE_ID_INTEL_HASWELL_S_GT2_IG,
 	    "Haswell", &sandybridge_gtt_driver },
-	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV,
+	{ PCI_DEVICE_ID_INTEL_HASWELL_S_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_D_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_M_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_SDV_S_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_D_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_M_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_ULT_S_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_D_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_M_GT2_PLUS_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT1_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT2_IG,
+	    "Haswell", &sandybridge_gtt_driver },
+	{ PCI_DEVICE_ID_INTEL_HASWELL_CRW_S_GT2_PLUS_IG,
 	    "Haswell", &sandybridge_gtt_driver },
 	{ 0, NULL, NULL }
 };

drivers/gpu/drm/i915/i915_drv.c

@@ -346,11 +346,40 @@ static const struct pci_device_id pciidlist[] = {		/* aka */
 	INTEL_VGA_DEVICE(0x016a, &intel_ivybridge_d_info), /* GT2 server */
 	INTEL_VGA_DEVICE(0x0402, &intel_haswell_d_info), /* GT1 desktop */
 	INTEL_VGA_DEVICE(0x0412, &intel_haswell_d_info), /* GT2 desktop */
+	INTEL_VGA_DEVICE(0x0422, &intel_haswell_d_info), /* GT2 desktop */
 	INTEL_VGA_DEVICE(0x040a, &intel_haswell_d_info), /* GT1 server */
 	INTEL_VGA_DEVICE(0x041a, &intel_haswell_d_info), /* GT2 server */
+	INTEL_VGA_DEVICE(0x042a, &intel_haswell_d_info), /* GT2 server */
 	INTEL_VGA_DEVICE(0x0406, &intel_haswell_m_info), /* GT1 mobile */
 	INTEL_VGA_DEVICE(0x0416, &intel_haswell_m_info), /* GT2 mobile */
-	INTEL_VGA_DEVICE(0x0c16, &intel_haswell_d_info), /* SDV */
+	INTEL_VGA_DEVICE(0x0426, &intel_haswell_m_info), /* GT2 mobile */
+	INTEL_VGA_DEVICE(0x0C02, &intel_haswell_d_info), /* SDV GT1 desktop */
+	INTEL_VGA_DEVICE(0x0C12, &intel_haswell_d_info), /* SDV GT2 desktop */
+	INTEL_VGA_DEVICE(0x0C22, &intel_haswell_d_info), /* SDV GT2 desktop */
+	INTEL_VGA_DEVICE(0x0C0A, &intel_haswell_d_info), /* SDV GT1 server */
+	INTEL_VGA_DEVICE(0x0C1A, &intel_haswell_d_info), /* SDV GT2 server */
+	INTEL_VGA_DEVICE(0x0C2A, &intel_haswell_d_info), /* SDV GT2 server */
+	INTEL_VGA_DEVICE(0x0C06, &intel_haswell_m_info), /* SDV GT1 mobile */
+	INTEL_VGA_DEVICE(0x0C16, &intel_haswell_m_info), /* SDV GT2 mobile */
+	INTEL_VGA_DEVICE(0x0C26, &intel_haswell_m_info), /* SDV GT2 mobile */
+	INTEL_VGA_DEVICE(0x0A02, &intel_haswell_d_info), /* ULT GT1 desktop */
+	INTEL_VGA_DEVICE(0x0A12, &intel_haswell_d_info), /* ULT GT2 desktop */
+	INTEL_VGA_DEVICE(0x0A22, &intel_haswell_d_info), /* ULT GT2 desktop */
+	INTEL_VGA_DEVICE(0x0A0A, &intel_haswell_d_info), /* ULT GT1 server */
+	INTEL_VGA_DEVICE(0x0A1A, &intel_haswell_d_info), /* ULT GT2 server */
+	INTEL_VGA_DEVICE(0x0A2A, &intel_haswell_d_info), /* ULT GT2 server */
+	INTEL_VGA_DEVICE(0x0A06, &intel_haswell_m_info), /* ULT GT1 mobile */
+	INTEL_VGA_DEVICE(0x0A16, &intel_haswell_m_info), /* ULT GT2 mobile */
+	INTEL_VGA_DEVICE(0x0A26, &intel_haswell_m_info), /* ULT GT2 mobile */
+	INTEL_VGA_DEVICE(0x0D12, &intel_haswell_d_info), /* CRW GT1 desktop */
+	INTEL_VGA_DEVICE(0x0D22, &intel_haswell_d_info), /* CRW GT2 desktop */
+	INTEL_VGA_DEVICE(0x0D32, &intel_haswell_d_info), /* CRW GT2 desktop */
+	INTEL_VGA_DEVICE(0x0D1A, &intel_haswell_d_info), /* CRW GT1 server */
+	INTEL_VGA_DEVICE(0x0D2A, &intel_haswell_d_info), /* CRW GT2 server */
+	INTEL_VGA_DEVICE(0x0D3A, &intel_haswell_d_info), /* CRW GT2 server */
+	INTEL_VGA_DEVICE(0x0D16, &intel_haswell_m_info), /* CRW GT1 mobile */
+	INTEL_VGA_DEVICE(0x0D26, &intel_haswell_m_info), /* CRW GT2 mobile */
+	INTEL_VGA_DEVICE(0x0D36, &intel_haswell_m_info), /* CRW GT2 mobile */
 	INTEL_VGA_DEVICE(0x0f30, &intel_valleyview_m_info),
 	INTEL_VGA_DEVICE(0x0157, &intel_valleyview_m_info),
 	INTEL_VGA_DEVICE(0x0155, &intel_valleyview_d_info),

drivers/gpu/drm/i915/i915_gem_context.c

@@ -451,7 +451,6 @@ int i915_switch_context(struct intel_ring_buffer *ring,
 	struct drm_i915_file_private *file_priv = NULL;
 	struct i915_hw_context *to;
 	struct drm_i915_gem_object *from_obj = ring->last_context_obj;
-	int ret;
 
 	if (dev_priv->hw_contexts_disabled)
 		return 0;

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -291,6 +291,16 @@ i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
 	target_i915_obj = to_intel_bo(target_obj);
 	target_offset = target_i915_obj->gtt_offset;
 
+	/* Sandybridge PPGTT errata: We need a global gtt mapping for MI and
+	 * pipe_control writes because the gpu doesn't properly redirect them
+	 * through the ppgtt for non_secure batchbuffers. */
+	if (unlikely(IS_GEN6(dev) &&
+	    reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION &&
+	    !target_i915_obj->has_global_gtt_mapping)) {
+		i915_gem_gtt_bind_object(target_i915_obj,
+					 target_i915_obj->cache_level);
+	}
+
 	/* The target buffer should have appeared before us in the
 	 * exec_object list, so it should have a GTT space bound by now.
 	 */
@@ -399,16 +409,6 @@ i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
 		io_mapping_unmap_atomic(reloc_page);
 	}
 
-	/* Sandybridge PPGTT errata: We need a global gtt mapping for MI and
-	 * pipe_control writes because the gpu doesn't properly redirect them
-	 * through the ppgtt for non_secure batchbuffers. */
-	if (unlikely(IS_GEN6(dev) &&
-	    reloc->write_domain == I915_GEM_DOMAIN_INSTRUCTION &&
-	    !target_i915_obj->has_global_gtt_mapping)) {
-		i915_gem_gtt_bind_object(target_i915_obj,
-					 target_i915_obj->cache_level);
-	}
-
 	/* and update the user's relocation entry */
 	reloc->presumed_offset = target_offset;
 

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -361,7 +361,8 @@ int i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj)
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
-	if (dev_priv->mm.gtt->needs_dmar)
+	/* don't map imported dma buf objects */
+	if (dev_priv->mm.gtt->needs_dmar && !obj->sg_table)
 		return intel_gtt_map_memory(obj->pages,
 					    obj->base.size >> PAGE_SHIFT,
 					    &obj->sg_list,

drivers/gpu/drm/i915/i915_sysfs.c

@@ -32,6 +32,7 @@
 #include "intel_drv.h"
 #include "i915_drv.h"
 
+#ifdef CONFIG_PM
 static u32 calc_residency(struct drm_device *dev, const u32 reg)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -224,3 +225,14 @@ void i915_teardown_sysfs(struct drm_device *dev)
 	device_remove_bin_file(&dev->primary->kdev,  &dpf_attrs);
 	sysfs_unmerge_group(&dev->primary->kdev.kobj, &rc6_attr_group);
 }
+#else
+void i915_setup_sysfs(struct drm_device *dev)
+{
+	return;
+}
+
+void i915_teardown_sysfs(struct drm_device *dev)
+{
+	return;
+}
+#endif /* CONFIG_PM */

drivers/gpu/drm/i915/intel_display.c

@@ -869,6 +869,7 @@ intel_vlv_find_best_pll(const intel_limit_t *limit, struct drm_crtc *crtc,
 	unsigned long bestppm, ppm, absppm;
 	int dotclk, flag;
 
+	flag = 0;
 	dotclk = target * 1000;
 	bestppm = 1000000;
 	ppm = absppm = 0;

drivers/gpu/drm/i915/intel_drv.h

@@ -46,13 +46,14 @@
 })
 
 #define wait_for_atomic_us(COND, US) ({ \
-	int i, ret__ = -ETIMEDOUT;	\
-	for (i = 0; i < (US); i++) {	\
-		if ((COND)) {		\
-			ret__ = 0;	\
+	unsigned long timeout__ = jiffies + usecs_to_jiffies(US);	\
+	int ret__ = 0;							\
+	while (!(COND)) {						\
+		if (time_after(jiffies, timeout__)) {			\
+			ret__ = -ETIMEDOUT;				\
 			break;						\
 		}							\
-		udelay(1);		\
+		cpu_relax();						\
 	}								\
 	ret__;								\
 })
@@ -380,7 +381,6 @@ extern void intel_pch_panel_fitting(struct drm_device *dev,
 				    const struct drm_display_mode *mode,
 				    struct drm_display_mode *adjusted_mode);
 extern u32 intel_panel_get_max_backlight(struct drm_device *dev);
-extern u32 intel_panel_get_backlight(struct drm_device *dev);
 extern void intel_panel_set_backlight(struct drm_device *dev, u32 level);
 extern int intel_panel_setup_backlight(struct drm_device *dev);
 extern void intel_panel_enable_backlight(struct drm_device *dev,

drivers/gpu/drm/i915/intel_i2c.c

@@ -540,9 +540,6 @@ void intel_teardown_gmbus(struct drm_device *dev)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int i;
 
-	if (dev_priv->gmbus == NULL)
-		return;
-
 	for (i = 0; i < GMBUS_NUM_PORTS; i++) {
 		struct intel_gmbus *bus = &dev_priv->gmbus[i];
 		i2c_del_adapter(&bus->adapter);

drivers/gpu/drm/i915/intel_panel.c

@@ -213,7 +213,7 @@ static u32 intel_panel_compute_brightness(struct drm_device *dev, u32 val)
 	return val;
 }
 
-u32 intel_panel_get_backlight(struct drm_device *dev)
+static u32 intel_panel_get_backlight(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 val;

drivers/gpu/drm/i915/intel_pm.c

@@ -3963,6 +3963,7 @@ static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
 		DRM_ERROR("Force wake wait timed out\n");
 
 	I915_WRITE_NOTRACE(FORCEWAKE, 1);
+	POSTING_READ(FORCEWAKE);
 
 	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1), 500))
 		DRM_ERROR("Force wake wait timed out\n");
@@ -3983,6 +3984,7 @@ static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
 		DRM_ERROR("Force wake wait timed out\n");
 
 	I915_WRITE_NOTRACE(FORCEWAKE_MT, _MASKED_BIT_ENABLE(1));
+	POSTING_READ(FORCEWAKE_MT);
 
 	if (wait_for_atomic_us((I915_READ_NOTRACE(forcewake_ack) & 1), 500))
 		DRM_ERROR("Force wake wait timed out\n");
@@ -4018,14 +4020,14 @@ void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)
 static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
 {
 	I915_WRITE_NOTRACE(FORCEWAKE, 0);
-	/* The below doubles as a POSTING_READ */
+	POSTING_READ(FORCEWAKE);
 	gen6_gt_check_fifodbg(dev_priv);
 }
 
 static void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
 {
 	I915_WRITE_NOTRACE(FORCEWAKE_MT, _MASKED_BIT_DISABLE(1));
-	/* The below doubles as a POSTING_READ */
+	POSTING_READ(FORCEWAKE_MT);
 	gen6_gt_check_fifodbg(dev_priv);
 }
 

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -289,8 +289,6 @@ static int init_ring_common(struct intel_ring_buffer *ring)
 	I915_WRITE_HEAD(ring, 0);
 	ring->write_tail(ring, 0);
 
-	/* Initialize the ring. */
-	I915_WRITE_START(ring, obj->gtt_offset);
 	head = I915_READ_HEAD(ring) & HEAD_ADDR;
 
 	/* G45 ring initialization fails to reset head to zero */
@@ -316,6 +314,11 @@ static int init_ring_common(struct intel_ring_buffer *ring)
 		}
 	}
 
+	/* Initialize the ring. This must happen _after_ we've cleared the ring
+	 * registers with the above sequence (the readback of the HEAD registers
+	 * also enforces ordering), otherwise the hw might lose the new ring
+	 * register values. */
+	I915_WRITE_START(ring, obj->gtt_offset);
 	I915_WRITE_CTL(ring,
 			((ring->size - PAGE_SIZE) & RING_NR_PAGES)
 			| RING_VALID);

drivers/gpu/drm/i915/intel_sdvo.c

@@ -444,13 +444,16 @@ static bool intel_sdvo_write_cmd(struct intel_sdvo *intel_sdvo, u8 cmd,
 	struct i2c_msg *msgs;
 	int i, ret = true;
 
+        /* Would be simpler to allocate both in one go ? */        
 	buf = (u8 *)kzalloc(args_len * 2 + 2, GFP_KERNEL);
 	if (!buf)
 		return false;
 
 	msgs = kcalloc(args_len + 3, sizeof(*msgs), GFP_KERNEL);
-	if (!msgs)
+	if (!msgs) {
+	        kfree(buf);
 		return false;
+        }
 
 	intel_sdvo_debug_write(intel_sdvo, cmd, args, args_len);