[Intel-gfx] [PATCH] drm/i915: Use POSTING_READ in lcpll code

Daniel Vetter daniel.vetter at ffwll.ch
Wed Aug 21 23:38:08 CEST 2013


If we don't use the return value of a mmio read our coding style is to
use the POSTING_READ macro. This avoids cluttering the mmio traces.

While at it add the missing posting read in the lcpll enable function
that Paulo spotted.

v2: Drop the _NOTRACE changes, tracing such wait_for loops in the modeset
code might actually be rather useful!

Cc: Paulo Zanoni <przanoni at gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/intel_display.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7a40427..937fc5a6 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6036,13 +6036,14 @@ void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
 	if (val & LCPLL_POWER_DOWN_ALLOW) {
 		val &= ~LCPLL_POWER_DOWN_ALLOW;
 		I915_WRITE(LCPLL_CTL, val);
+		POSTING_READ(LCPLL_CTL);
 	}
 
 	val = I915_READ(D_COMP);
 	val |= D_COMP_COMP_FORCE;
 	val &= ~D_COMP_COMP_DISABLE;
 	I915_WRITE(D_COMP, val);
-	I915_READ(D_COMP);
+	POSTING_READ(D_COMP);
 
 	val = I915_READ(LCPLL_CTL);
 	val &= ~LCPLL_PLL_DISABLE;
-- 
1.8.4.rc3




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