drm/i915: Capture interesting display registers on error

When trying to diagnose mysterious errors on resume, capture the
display register contents as well.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 24a88ac..421b841 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -729,6 +729,9 @@
 	if (error->overlay)
 		intel_overlay_print_error_state(m, error->overlay);
 
+	if (error->display)
+		intel_display_print_error_state(m, dev, error->display);
+
 out:
 	spin_unlock_irqrestore(&dev_priv->error_lock, flags);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 826c723..4c20ad9 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -140,6 +140,8 @@
 	u8 ddc_pin;
 };
 
+struct intel_display_error_state;
+
 struct drm_i915_error_state {
 	u32 eir;
 	u32 pgtbl_er;
@@ -187,6 +189,7 @@
 	} *active_bo, *pinned_bo;
 	u32 active_bo_count, pinned_bo_count;
 	struct intel_overlay_error_state *overlay;
+	struct intel_display_error_state *display;
 };
 
 struct drm_i915_display_funcs {
@@ -1223,6 +1226,11 @@
 #ifdef CONFIG_DEBUG_FS
 extern struct intel_overlay_error_state *intel_overlay_capture_error_state(struct drm_device *dev);
 extern void intel_overlay_print_error_state(struct seq_file *m, struct intel_overlay_error_state *error);
+
+extern struct intel_display_error_state *intel_display_capture_error_state(struct drm_device *dev);
+extern void intel_display_print_error_state(struct seq_file *m,
+					    struct drm_device *dev,
+					    struct intel_display_error_state *error);
 #endif
 
 /**
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index bbcd5da..0b6052a 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -766,6 +766,7 @@
 	do_gettimeofday(&error->time);
 
 	error->overlay = intel_overlay_capture_error_state(dev);
+	error->display = intel_display_capture_error_state(dev);
 
 	spin_lock_irqsave(&dev_priv->error_lock, flags);
 	if (dev_priv->first_error == NULL) {
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 886c0e0..ec2a8b0 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1193,7 +1193,6 @@
 #define VTOTAL(pipe) _PIPE(pipe, VTOTAL_A, VTOTAL_B)
 #define VBLANK(pipe) _PIPE(pipe, VBLANK_A, VBLANK_B)
 #define VSYNC(pipe) _PIPE(pipe, VSYNC_A, VSYNC_B)
-#define PIPESRC(pipe) _PIPE(pipe, PIPEASRC, PIPEBSRC)
 #define BCLRPAT(pipe) _PIPE(pipe, BCLRPAT_A, BCLRPAT_B)
 
 /* VGA port control */
@@ -2207,6 +2206,7 @@
 #define   PIPE_6BPC				(2 << 5)
 #define   PIPE_12BPC				(3 << 5)
 
+#define PIPESRC(pipe) _PIPE(pipe, PIPEASRC, PIPEBSRC)
 #define PIPECONF(pipe) _PIPE(pipe, PIPEACONF, PIPEBCONF)
 #define PIPEDSL(pipe)  _PIPE(pipe, PIPEADSL, PIPEBDSL)
 
@@ -2376,6 +2376,10 @@
 #define CURBBASE		0x700c4
 #define CURBPOS			0x700c8
 
+#define CURCNTR(pipe) _PIPE(pipe, CURACNTR, CURBCNTR)
+#define CURBASE(pipe) _PIPE(pipe, CURABASE, CURBBASE)
+#define CURPOS(pipe) _PIPE(pipe, CURAPOS, CURBPOS)
+
 /* Display A control */
 #define DSPACNTR                0x70180
 #define   DISPLAY_PLANE_ENABLE			(1<<31)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3fa5aaa..d4bc443 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6269,3 +6269,113 @@
 	pci_write_config_word(dev_priv->bridge_dev, INTEL_GMCH_CTRL, gmch_ctrl);
 	return 0;
 }
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/seq_file.h>
+
+struct intel_display_error_state {
+	struct intel_cursor_error_state {
+		u32 control;
+		u32 position;
+		u32 base;
+		u32 size;
+	} cursor[2];
+
+	struct intel_pipe_error_state {
+		u32 conf;
+		u32 source;
+
+		u32 htotal;
+		u32 hblank;
+		u32 hsync;
+		u32 vtotal;
+		u32 vblank;
+		u32 vsync;
+	} pipe[2];
+
+	struct intel_plane_error_state {
+		u32 control;
+		u32 stride;
+		u32 size;
+		u32 pos;
+		u32 addr;
+		u32 surface;
+		u32 tile_offset;
+	} plane[2];
+};
+
+struct intel_display_error_state *
+intel_display_capture_error_state(struct drm_device *dev)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_display_error_state *error;
+	int i;
+
+	error = kmalloc(sizeof(*error), GFP_ATOMIC);
+	if (error == NULL)
+		return NULL;
+
+	for (i = 0; i < 2; i++) {
+		error->cursor[i].control = I915_READ(CURCNTR(i));
+		error->cursor[i].position = I915_READ(CURPOS(i));
+		error->cursor[i].base = I915_READ(CURBASE(i));
+
+		error->plane[i].control = I915_READ(DSPCNTR(i));
+		error->plane[i].stride = I915_READ(DSPSTRIDE(i));
+		error->plane[i].size = I915_READ(DSPSIZE(i));
+		error->plane[i].pos= I915_READ(DSPPOS(i));
+		error->plane[i].addr = I915_READ(DSPADDR(i));
+		if (INTEL_INFO(dev)->gen >= 4) {
+			error->plane[i].surface = I915_READ(DSPSURF(i));
+			error->plane[i].tile_offset = I915_READ(DSPTILEOFF(i));
+		}
+
+		error->pipe[i].conf = I915_READ(PIPECONF(i));
+		error->pipe[i].source = I915_READ(PIPESRC(i));
+		error->pipe[i].htotal = I915_READ(HTOTAL(i));
+		error->pipe[i].hblank = I915_READ(HBLANK(i));
+		error->pipe[i].hsync = I915_READ(HSYNC(i));
+		error->pipe[i].vtotal = I915_READ(VTOTAL(i));
+		error->pipe[i].vblank = I915_READ(VBLANK(i));
+		error->pipe[i].vsync = I915_READ(VSYNC(i));
+	}
+
+	return error;
+}
+
+void
+intel_display_print_error_state(struct seq_file *m,
+				struct drm_device *dev,
+				struct intel_display_error_state *error)
+{
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		seq_printf(m, "Pipe [%d]:\n", i);
+		seq_printf(m, "  CONF: %08x\n", error->pipe[i].conf);
+		seq_printf(m, "  SRC: %08x\n", error->pipe[i].source);
+		seq_printf(m, "  HTOTAL: %08x\n", error->pipe[i].htotal);
+		seq_printf(m, "  HBLANK: %08x\n", error->pipe[i].hblank);
+		seq_printf(m, "  HSYNC: %08x\n", error->pipe[i].hsync);
+		seq_printf(m, "  VTOTAL: %08x\n", error->pipe[i].vtotal);
+		seq_printf(m, "  VBLANK: %08x\n", error->pipe[i].vblank);
+		seq_printf(m, "  VSYNC: %08x\n", error->pipe[i].vsync);
+
+		seq_printf(m, "Plane [%d]:\n", i);
+		seq_printf(m, "  CNTR: %08x\n", error->plane[i].control);
+		seq_printf(m, "  STRIDE: %08x\n", error->plane[i].stride);
+		seq_printf(m, "  SIZE: %08x\n", error->plane[i].size);
+		seq_printf(m, "  POS: %08x\n", error->plane[i].pos);
+		seq_printf(m, "  ADDR: %08x\n", error->plane[i].addr);
+		if (INTEL_INFO(dev)->gen >= 4) {
+			seq_printf(m, "  SURF: %08x\n", error->plane[i].surface);
+			seq_printf(m, "  TILEOFF: %08x\n", error->plane[i].tile_offset);
+		}
+
+		seq_printf(m, "Cursor [%d]:\n", i);
+		seq_printf(m, "  CNTR: %08x\n", error->cursor[i].control);
+		seq_printf(m, "  POS: %08x\n", error->cursor[i].position);
+		seq_printf(m, "  BASE: %08x\n", error->cursor[i].base);
+	}
+}
+#endif