drm/i915: Round up the watermark entries (v3)

Even though "we have enough padding that it should be ok", round up the
watermark entries to the next unit to be on the safe side...

v2: Use the DIV_ROUND_UP macro
v3: Spotted a few more missing round-ups.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index ce96c3a..baaaeaa 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2734,7 +2734,7 @@
 	 */
 	entries_required = ((clock_in_khz / 1000) * pixel_size * latency_ns) /
 		1000;
-	entries_required /= wm->cacheline_size;
+	entries_required = DIV_ROUND_UP(entries_required, wm->cacheline_size);
 
 	DRM_DEBUG_KMS("FIFO entries required for mode: %d\n", entries_required);
 
@@ -2855,11 +2855,9 @@
 	uint32_t dsparb = I915_READ(DSPARB);
 	int size;
 
-	if (plane == 0)
-		size = dsparb & 0x7f;
-	else
-		size = ((dsparb >> DSPARB_CSTART_SHIFT) & 0x7f) -
-			(dsparb & 0x7f);
+	size = dsparb & 0x7f;
+	if (plane)
+		size = ((dsparb >> DSPARB_CSTART_SHIFT) & 0x7f) - size;
 
 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
 			plane ? "B" : "A", size);
@@ -2873,11 +2871,9 @@
 	uint32_t dsparb = I915_READ(DSPARB);
 	int size;
 
-	if (plane == 0)
-		size = dsparb & 0x1ff;
-	else
-		size = ((dsparb >> DSPARB_BEND_SHIFT) & 0x1ff) -
-			(dsparb & 0x1ff);
+	size = dsparb & 0x1ff;
+	if (plane)
+		size = ((dsparb >> DSPARB_BEND_SHIFT) & 0x1ff) - size;
 	size >>= 1; /* Convert to cachelines */
 
 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
@@ -3009,12 +3005,12 @@
 	 */
 	entries_required = ((planea_clock / 1000) * pixel_size * latency_ns) /
 		1000;
-	entries_required /= G4X_FIFO_LINE_SIZE;
+	entries_required = DIV_ROUND_UP(entries_required, G4X_FIFO_LINE_SIZE);
 	planea_wm = entries_required + planea_params.guard_size;
 
 	entries_required = ((planeb_clock / 1000) * pixel_size * latency_ns) /
 		1000;
-	entries_required /= G4X_FIFO_LINE_SIZE;
+	entries_required = DIV_ROUND_UP(entries_required, G4X_FIFO_LINE_SIZE);
 	planeb_wm = entries_required + planeb_params.guard_size;
 
 	cursora_wm = cursorb_wm = 16;
@@ -3033,12 +3029,12 @@
 		/* Use ns/us then divide to preserve precision */
 		sr_entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
 			      pixel_size * sr_hdisplay;
-		sr_entries = roundup(sr_entries / cacheline_size, 1);
+		sr_entries = DIV_ROUND_UP(sr_entries, cacheline_size);
 
 		entries_required = (((sr_latency_ns / line_time_us) +
 				     1000) / 1000) * pixel_size * 64;
-		entries_required = roundup(entries_required /
-					   g4x_cursor_wm_info.cacheline_size, 1);
+		entries_required = DIV_ROUND_UP(entries_required,
+					   g4x_cursor_wm_info.cacheline_size);
 		cursor_sr = entries_required + g4x_cursor_wm_info.guard_size;
 
 		if (cursor_sr > g4x_cursor_wm_info.max_wm)
@@ -3089,7 +3085,7 @@
 		/* Use ns/us then divide to preserve precision */
 		sr_entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
 			      pixel_size * sr_hdisplay;
-		sr_entries = roundup(sr_entries / I915_FIFO_LINE_SIZE, 1);
+		sr_entries = DIV_ROUND_UP(sr_entries, I915_FIFO_LINE_SIZE);
 		DRM_DEBUG("self-refresh entries: %d\n", sr_entries);
 		srwm = I965_FIFO_SIZE - sr_entries;
 		if (srwm < 0)
@@ -3098,8 +3094,8 @@
 
 		sr_entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
 			     pixel_size * 64;
-		sr_entries = roundup(sr_entries /
-				     i965_cursor_wm_info.cacheline_size, 1);
+		sr_entries = DIV_ROUND_UP(sr_entries,
+					  i965_cursor_wm_info.cacheline_size);
 		cursor_sr = i965_cursor_wm_info.fifo_size -
 			    (sr_entries + i965_cursor_wm_info.guard_size);
 
@@ -3181,7 +3177,7 @@
 		/* Use ns/us then divide to preserve precision */
 		sr_entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
 			      pixel_size * sr_hdisplay;
-		sr_entries = roundup(sr_entries / cacheline_size, 1);
+		sr_entries = DIV_ROUND_UP(sr_entries, cacheline_size);
 		DRM_DEBUG_KMS("self-refresh entries: %d\n", sr_entries);
 		srwm = total_size - sr_entries;
 		if (srwm < 0)
@@ -3270,7 +3266,7 @@
 		entries_required = ((planea_clock / 1000) * pixel_size *
 				     ILK_LP0_PLANE_LATENCY) / 1000;
 		entries_required = DIV_ROUND_UP(entries_required,
-				   ironlake_display_wm_info.cacheline_size);
+						ironlake_display_wm_info.cacheline_size);
 		planea_wm = entries_required +
 			    ironlake_display_wm_info.guard_size;
 
@@ -3304,7 +3300,7 @@
 		entries_required = ((planeb_clock / 1000) * pixel_size *
 				     ILK_LP0_PLANE_LATENCY) / 1000;
 		entries_required = DIV_ROUND_UP(entries_required,
-				   ironlake_display_wm_info.cacheline_size);
+						ironlake_display_wm_info.cacheline_size);
 		planeb_wm = entries_required +
 			    ironlake_display_wm_info.guard_size;
 
@@ -3353,14 +3349,14 @@
 		/* calculate the self-refresh watermark for display plane */
 		entries_required = line_count * sr_hdisplay * pixel_size;
 		entries_required = DIV_ROUND_UP(entries_required,
-				   ironlake_display_srwm_info.cacheline_size);
+						ironlake_display_srwm_info.cacheline_size);
 		sr_wm = entries_required +
 			ironlake_display_srwm_info.guard_size;
 
 		/* calculate the self-refresh watermark for display cursor */
 		entries_required = line_count * pixel_size * 64;
 		entries_required = DIV_ROUND_UP(entries_required,
-				   ironlake_cursor_srwm_info.cacheline_size);
+						ironlake_cursor_srwm_info.cacheline_size);
 		cursor_wm = entries_required +
 			    ironlake_cursor_srwm_info.guard_size;