drm/i915: fixup sparse warnings

- __iomem where there is none (I love how we mix these things up).
- Use gfp_t instead of an other plain type.
- Unconfuse one place about enum pipe vs enum transcoder - for the pch
  transcoder we actually use the pipe enum. Fixup the other cases
  where we assign the pipe to the cpu transcoder with explicit casts.
- Declare the mch_lock properly in a header.

There is still a decent mess in intel_bios.c about __iomem, but heck,
this is x86 and we're allowed to do that.

Makes-sparse-happy: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Use a space after the cast consistently and fix up the
newly-added cast in i915_irq.c to properly use __iomem.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_debugfs.c

@@ -546,11 +546,11 @@ static int i915_hws_info(struct seq_file *m, void *data)
 	struct drm_device *dev = node->minor->dev;
 	drm_i915_private_t *dev_priv = dev->dev_private;
 	struct intel_ring_buffer *ring;
-	const volatile u32 __iomem *hws;
+	const u32 *hws;
 	int i;
 
 	ring = &dev_priv->ring[(uintptr_t)node->info_ent->data];
-	hws = (volatile u32 __iomem *)ring->status_page.page_addr;
+	hws = ring->status_page.page_addr;
 	if (hws == NULL)
 		return 0;
 

drivers/gpu/drm/i915/i915_drv.h

@@ -577,6 +577,9 @@ struct intel_gen6_power_mgmt {
 	struct mutex hw_lock;
 };
 
+/* defined intel_pm.c */
+extern spinlock_t mchdev_lock;
+
 struct intel_ilk_power_mgmt {
 	u8 cur_delay;
 	u8 min_delay;

drivers/gpu/drm/i915/i915_gem.c

@@ -3705,7 +3705,7 @@ struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
 {
 	struct drm_i915_gem_object *obj;
 	struct address_space *mapping;
-	u32 mask;
+	gfp_t mask;
 
 	obj = i915_gem_object_alloc(dev);
 	if (obj == NULL)

drivers/gpu/drm/i915/i915_irq.c

@@ -300,9 +300,6 @@ static void i915_hotplug_work_func(struct work_struct *work)
 	drm_helper_hpd_irq_event(dev);
 }
 
-/* defined intel_pm.c */
-extern spinlock_t mchdev_lock;
-
 static void ironlake_handle_rps_change(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
@@ -936,7 +933,7 @@ i915_error_object_create(struct drm_i915_private *dev_priv,
 			offset += src->stolen->start;
 			offset += i << PAGE_SHIFT;
 
-			memcpy_fromio(d, (void *)offset, PAGE_SIZE);
+			memcpy_fromio(d, (void __iomem *) offset, PAGE_SIZE);
 		} else {
 			struct page *page;
 			void *s;

drivers/gpu/drm/i915/intel_ddi.c

@@ -1044,7 +1044,7 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector)
 	if (port == PORT_A)
 		cpu_transcoder = TRANSCODER_EDP;
 	else
-		cpu_transcoder = pipe;
+		cpu_transcoder = (enum transcoder) pipe;
 
 	tmp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
 

drivers/gpu/drm/i915/intel_display.c

@@ -1671,7 +1671,7 @@ static void lpt_enable_pch_transcoder(struct drm_i915_private *dev_priv,
 	BUG_ON(dev_priv->info->gen < 5);
 
 	/* FDI must be feeding us bits for PCH ports */
-	assert_fdi_tx_enabled(dev_priv, cpu_transcoder);
+	assert_fdi_tx_enabled(dev_priv, (enum pipe) cpu_transcoder);
 	assert_fdi_rx_enabled(dev_priv, TRANSCODER_A);
 
 	/* Workaround: set timing override bit. */
@@ -1759,7 +1759,7 @@ static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe,
 {
 	enum transcoder cpu_transcoder = intel_pipe_to_cpu_transcoder(dev_priv,
 								      pipe);
-	enum transcoder pch_transcoder;
+	enum pipe pch_transcoder;
 	int reg;
 	u32 val;
 
@@ -1779,7 +1779,8 @@ static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe,
 		if (pch_port) {
 			/* if driving the PCH, we need FDI enabled */
 			assert_fdi_rx_pll_enabled(dev_priv, pch_transcoder);
-			assert_fdi_tx_pll_enabled(dev_priv, cpu_transcoder);
+			assert_fdi_tx_pll_enabled(dev_priv,
+						  (enum pipe) cpu_transcoder);
 		}
 		/* FIXME: assert CPU port conditions for SNB+ */
 	}
@@ -3598,7 +3599,7 @@ static void haswell_crtc_off(struct drm_crtc *crtc)
 
 	/* Stop saying we're using TRANSCODER_EDP because some other CRTC might
 	 * start using it. */
-	intel_crtc->cpu_transcoder = intel_crtc->pipe;
+	intel_crtc->cpu_transcoder = (enum transcoder) intel_crtc->pipe;
 
 	intel_ddi_put_crtc_pll(crtc);
 }