drm/i915: Use I915_READ_FW for plane updates

Optimize the plane register accesses a little bit by grabbing
the uncore lock manually across the entire pile of accesses and
using I915_READ_FW().

This helps keep the pipe update vblank evade critical section
below our 100 usec deadline, particularly with lockdep enabled.
And in general we want to keep that critical section as short
as possible as it's executed with interrupts disabled.

Not all plane updates currently happen from within the vblank evade
critical section, so we must use the irqsave/irqrestore variants
of the spinlock functions in the plane hooks.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170309154434.29303-5-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

1 files changed, 94 insertions, 64 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 357dce647068..4b73513b46c1 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2976,6 +2976,7 @@ static void i9xx_update_primary_plane(struct drm_plane *primary,
 	unsigned int rotation = plane_state->base.rotation;
 	int x = plane_state->base.src.x1 >> 16;
 	int y = plane_state->base.src.y1 >> 16;
+	unsigned long irqflags;
 
 	dspcntr = DISPPLANE_GAMMA_ENABLE;
 
@@ -3046,37 +3047,41 @@ static void i9xx_update_primary_plane(struct drm_plane *primary,
 	intel_crtc->adjusted_x = x;
 	intel_crtc->adjusted_y = y;
 
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
 	if (INTEL_GEN(dev_priv) < 4) {
 		/* pipesrc and dspsize control the size that is scaled from,
 		 * which should always be the user's requested size.
 		 */
-		I915_WRITE(DSPSIZE(plane),
-			   ((crtc_state->pipe_src_h - 1) << 16) |
-			   (crtc_state->pipe_src_w - 1));
-		I915_WRITE(DSPPOS(plane), 0);
+		I915_WRITE_FW(DSPSIZE(plane),
+			      ((crtc_state->pipe_src_h - 1) << 16) |
+			      (crtc_state->pipe_src_w - 1));
+		I915_WRITE_FW(DSPPOS(plane), 0);
 	} else if (IS_CHERRYVIEW(dev_priv) && plane == PLANE_B) {
-		I915_WRITE(PRIMSIZE(plane),
-			   ((crtc_state->pipe_src_h - 1) << 16) |
-			   (crtc_state->pipe_src_w - 1));
-		I915_WRITE(PRIMPOS(plane), 0);
-		I915_WRITE(PRIMCNSTALPHA(plane), 0);
+		I915_WRITE_FW(PRIMSIZE(plane),
+			      ((crtc_state->pipe_src_h - 1) << 16) |
+			      (crtc_state->pipe_src_w - 1));
+		I915_WRITE_FW(PRIMPOS(plane), 0);
+		I915_WRITE_FW(PRIMCNSTALPHA(plane), 0);
 	}
 
-	I915_WRITE(reg, dspcntr);
+	I915_WRITE_FW(reg, dspcntr);
 
-	I915_WRITE(DSPSTRIDE(plane), fb->pitches[0]);
+	I915_WRITE_FW(DSPSTRIDE(plane), fb->pitches[0]);
 	if (INTEL_GEN(dev_priv) >= 4) {
-		I915_WRITE(DSPSURF(plane),
-			   intel_plane_ggtt_offset(plane_state) +
-			   intel_crtc->dspaddr_offset);
-		I915_WRITE(DSPTILEOFF(plane), (y << 16) | x);
-		I915_WRITE(DSPLINOFF(plane), linear_offset);
+		I915_WRITE_FW(DSPSURF(plane),
+			      intel_plane_ggtt_offset(plane_state) +
+			      intel_crtc->dspaddr_offset);
+		I915_WRITE_FW(DSPTILEOFF(plane), (y << 16) | x);
+		I915_WRITE_FW(DSPLINOFF(plane), linear_offset);
 	} else {
-		I915_WRITE(DSPADDR(plane),
-			   intel_plane_ggtt_offset(plane_state) +
-			   intel_crtc->dspaddr_offset);
+		I915_WRITE_FW(DSPADDR(plane),
+			      intel_plane_ggtt_offset(plane_state) +
+			      intel_crtc->dspaddr_offset);
 	}
-	POSTING_READ(reg);
+	POSTING_READ_FW(reg);
+
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 static void i9xx_disable_primary_plane(struct drm_plane *primary,
@@ -3086,13 +3091,18 @@ static void i9xx_disable_primary_plane(struct drm_plane *primary,
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	int plane = intel_crtc->plane;
+	unsigned long irqflags;
 
-	I915_WRITE(DSPCNTR(plane), 0);
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+	I915_WRITE_FW(DSPCNTR(plane), 0);
 	if (INTEL_INFO(dev_priv)->gen >= 4)
-		I915_WRITE(DSPSURF(plane), 0);
+		I915_WRITE_FW(DSPSURF(plane), 0);
 	else
-		I915_WRITE(DSPADDR(plane), 0);
-	POSTING_READ(DSPCNTR(plane));
+		I915_WRITE_FW(DSPADDR(plane), 0);
+	POSTING_READ_FW(DSPCNTR(plane));
+
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 static void ironlake_update_primary_plane(struct drm_plane *primary,
@@ -3110,6 +3120,7 @@ static void ironlake_update_primary_plane(struct drm_plane *primary,
 	unsigned int rotation = plane_state->base.rotation;
 	int x = plane_state->base.src.x1 >> 16;
 	int y = plane_state->base.src.y1 >> 16;
+	unsigned long irqflags;
 
 	dspcntr = DISPPLANE_GAMMA_ENABLE;
 	dspcntr |= DISPLAY_PLANE_ENABLE;
@@ -3166,19 +3177,23 @@ static void ironlake_update_primary_plane(struct drm_plane *primary,
 	intel_crtc->adjusted_x = x;
 	intel_crtc->adjusted_y = y;
 
-	I915_WRITE(reg, dspcntr);
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+	I915_WRITE_FW(reg, dspcntr);
 
-	I915_WRITE(DSPSTRIDE(plane), fb->pitches[0]);
-	I915_WRITE(DSPSURF(plane),
-		   intel_plane_ggtt_offset(plane_state) +
-		   intel_crtc->dspaddr_offset);
+	I915_WRITE_FW(DSPSTRIDE(plane), fb->pitches[0]);
+	I915_WRITE_FW(DSPSURF(plane),
+		      intel_plane_ggtt_offset(plane_state) +
+		      intel_crtc->dspaddr_offset);
 	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
-		I915_WRITE(DSPOFFSET(plane), (y << 16) | x);
+		I915_WRITE_FW(DSPOFFSET(plane), (y << 16) | x);
 	} else {
-		I915_WRITE(DSPTILEOFF(plane), (y << 16) | x);
-		I915_WRITE(DSPLINOFF(plane), linear_offset);
+		I915_WRITE_FW(DSPTILEOFF(plane), (y << 16) | x);
+		I915_WRITE_FW(DSPLINOFF(plane), linear_offset);
 	}
-	POSTING_READ(reg);
+	POSTING_READ_FW(reg);
+
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 static u32
@@ -3343,6 +3358,7 @@ static void skylake_update_primary_plane(struct drm_plane *plane,
 	int dst_y = plane_state->base.dst.y1;
 	int dst_w = drm_rect_width(&plane_state->base.dst);
 	int dst_h = drm_rect_height(&plane_state->base.dst);
+	unsigned long irqflags;
 
 	plane_ctl = PLANE_CTL_ENABLE;
 
@@ -3368,17 +3384,19 @@ static void skylake_update_primary_plane(struct drm_plane *plane,
 	intel_crtc->adjusted_x = src_x;
 	intel_crtc->adjusted_y = src_y;
 
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
 	if (IS_GEMINILAKE(dev_priv)) {
-		I915_WRITE(PLANE_COLOR_CTL(pipe, plane_id),
-			   PLANE_COLOR_PIPE_GAMMA_ENABLE |
-			   PLANE_COLOR_PIPE_CSC_ENABLE |
-			   PLANE_COLOR_PLANE_GAMMA_DISABLE);
+		I915_WRITE_FW(PLANE_COLOR_CTL(pipe, plane_id),
+			      PLANE_COLOR_PIPE_GAMMA_ENABLE |
+			      PLANE_COLOR_PIPE_CSC_ENABLE |
+			      PLANE_COLOR_PLANE_GAMMA_DISABLE);
 	}
 
-	I915_WRITE(PLANE_CTL(pipe, plane_id), plane_ctl);
-	I915_WRITE(PLANE_OFFSET(pipe, plane_id), (src_y << 16) | src_x);
-	I915_WRITE(PLANE_STRIDE(pipe, plane_id), stride);
-	I915_WRITE(PLANE_SIZE(pipe, plane_id), (src_h << 16) | src_w);
+	I915_WRITE_FW(PLANE_CTL(pipe, plane_id), plane_ctl);
+	I915_WRITE_FW(PLANE_OFFSET(pipe, plane_id), (src_y << 16) | src_x);
+	I915_WRITE_FW(PLANE_STRIDE(pipe, plane_id), stride);
+	I915_WRITE_FW(PLANE_SIZE(pipe, plane_id), (src_h << 16) | src_w);
 
 	if (scaler_id >= 0) {
 		uint32_t ps_ctrl = 0;
@@ -3386,19 +3404,21 @@ static void skylake_update_primary_plane(struct drm_plane *plane,
 		WARN_ON(!dst_w || !dst_h);
 		ps_ctrl = PS_SCALER_EN | PS_PLANE_SEL(plane_id) |
 			crtc_state->scaler_state.scalers[scaler_id].mode;
-		I915_WRITE(SKL_PS_CTRL(pipe, scaler_id), ps_ctrl);
-		I915_WRITE(SKL_PS_PWR_GATE(pipe, scaler_id), 0);
-		I915_WRITE(SKL_PS_WIN_POS(pipe, scaler_id), (dst_x << 16) | dst_y);
-		I915_WRITE(SKL_PS_WIN_SZ(pipe, scaler_id), (dst_w << 16) | dst_h);
-		I915_WRITE(PLANE_POS(pipe, plane_id), 0);
+		I915_WRITE_FW(SKL_PS_CTRL(pipe, scaler_id), ps_ctrl);
+		I915_WRITE_FW(SKL_PS_PWR_GATE(pipe, scaler_id), 0);
+		I915_WRITE_FW(SKL_PS_WIN_POS(pipe, scaler_id), (dst_x << 16) | dst_y);
+		I915_WRITE_FW(SKL_PS_WIN_SZ(pipe, scaler_id), (dst_w << 16) | dst_h);
+		I915_WRITE_FW(PLANE_POS(pipe, plane_id), 0);
 	} else {
-		I915_WRITE(PLANE_POS(pipe, plane_id), (dst_y << 16) | dst_x);
+		I915_WRITE_FW(PLANE_POS(pipe, plane_id), (dst_y << 16) | dst_x);
 	}
 
-	I915_WRITE(PLANE_SURF(pipe, plane_id),
-		   intel_plane_ggtt_offset(plane_state) + surf_addr);
+	I915_WRITE_FW(PLANE_SURF(pipe, plane_id),
+		      intel_plane_ggtt_offset(plane_state) + surf_addr);
+
+	POSTING_READ_FW(PLANE_SURF(pipe, plane_id));
 
-	POSTING_READ(PLANE_SURF(pipe, plane_id));
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 static void skylake_disable_primary_plane(struct drm_plane *primary,
@@ -3408,10 +3428,15 @@ static void skylake_disable_primary_plane(struct drm_plane *primary,
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	enum plane_id plane_id = to_intel_plane(primary)->id;
 	enum pipe pipe = to_intel_plane(primary)->pipe;
+	unsigned long irqflags;
 
-	I915_WRITE(PLANE_CTL(pipe, plane_id), 0);
-	I915_WRITE(PLANE_SURF(pipe, plane_id), 0);
-	POSTING_READ(PLANE_SURF(pipe, plane_id));
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+	I915_WRITE_FW(PLANE_CTL(pipe, plane_id), 0);
+	I915_WRITE_FW(PLANE_SURF(pipe, plane_id), 0);
+	POSTING_READ_FW(PLANE_SURF(pipe, plane_id));
+
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 /* Assume fb object is pinned & idle & fenced and just update base pointers */
@@ -9175,24 +9200,24 @@ static void i845_update_cursor(struct drm_crtc *crtc, u32 base,
 		/* On these chipsets we can only modify the base/size/stride
 		 * whilst the cursor is disabled.
 		 */
-		I915_WRITE(CURCNTR(PIPE_A), 0);
-		POSTING_READ(CURCNTR(PIPE_A));
+		I915_WRITE_FW(CURCNTR(PIPE_A), 0);
+		POSTING_READ_FW(CURCNTR(PIPE_A));
 		intel_crtc->cursor_cntl = 0;
 	}
 
 	if (intel_crtc->cursor_base != base) {
-		I915_WRITE(CURBASE(PIPE_A), base);
+		I915_WRITE_FW(CURBASE(PIPE_A), base);
 		intel_crtc->cursor_base = base;
 	}
 
 	if (intel_crtc->cursor_size != size) {
-		I915_WRITE(CURSIZE, size);
+		I915_WRITE_FW(CURSIZE, size);
 		intel_crtc->cursor_size = size;
 	}
 
 	if (intel_crtc->cursor_cntl != cntl) {
-		I915_WRITE(CURCNTR(PIPE_A), cntl);
-		POSTING_READ(CURCNTR(PIPE_A));
+		I915_WRITE_FW(CURCNTR(PIPE_A), cntl);
+		POSTING_READ_FW(CURCNTR(PIPE_A));
 		intel_crtc->cursor_cntl = cntl;
 	}
 }
@@ -9232,14 +9257,14 @@ static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base,
 	}
 
 	if (intel_crtc->cursor_cntl != cntl) {
-		I915_WRITE(CURCNTR(pipe), cntl);
-		POSTING_READ(CURCNTR(pipe));
+		I915_WRITE_FW(CURCNTR(pipe), cntl);
+		POSTING_READ_FW(CURCNTR(pipe));
 		intel_crtc->cursor_cntl = cntl;
 	}
 
 	/* and commit changes on next vblank */
-	I915_WRITE(CURBASE(pipe), base);
-	POSTING_READ(CURBASE(pipe));
+	I915_WRITE_FW(CURBASE(pipe), base);
+	POSTING_READ_FW(CURBASE(pipe));
 
 	intel_crtc->cursor_base = base;
 }
@@ -9253,6 +9278,7 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	int pipe = intel_crtc->pipe;
 	u32 base = intel_crtc->cursor_addr;
+	unsigned long irqflags;
 	u32 pos = 0;
 
 	if (plane_state) {
@@ -9279,12 +9305,16 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 		}
 	}
 
-	I915_WRITE(CURPOS(pipe), pos);
+	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
+
+	I915_WRITE_FW(CURPOS(pipe), pos);
 
 	if (IS_I845G(dev_priv) || IS_I865G(dev_priv))
 		i845_update_cursor(crtc, base, plane_state);
 	else
 		i9xx_update_cursor(crtc, base, plane_state);
+
+	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
 }
 
 static bool cursor_size_ok(struct drm_i915_private *dev_priv,