From 652c393a3368af84359da37c45afc35a91144960 Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Mon, 17 Aug 2009 13:31:43 -0700 Subject: drm/i915: add dynamic clock frequency control There are several sources of unnecessary power consumption on Intel graphics systems. The first is the LVDS clock. TFTs don't suffer from persistence issues like CRTs, and so we can reduce the LVDS refresh rate when the screen is idle. It will be automatically upclocked when userspace triggers graphical activity. Beyond that, we can enable memory self refresh. This allows the memory to go into a lower power state when the graphics are idle. Finally, we can drop some clocks on the gpu itself. All of these things can be reenabled between frames when GPU activity is triggered, and so there should be no user visible graphical changes. Signed-off-by: Jesse Barnes Signed-off-by: Matthew Garrett Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_i2c.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/gpu/drm/i915/intel_i2c.c') diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index 62b8bead765..c7eab724c41 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -42,11 +42,11 @@ void intel_i2c_quirk_set(struct drm_device *dev, bool enable) if (!IS_IGD(dev)) return; if (enable) - I915_WRITE(CG_2D_DIS, - I915_READ(CG_2D_DIS) | DPCUNIT_CLOCK_GATE_DISABLE); + I915_WRITE(DSPCLK_GATE_D, + I915_READ(DSPCLK_GATE_D) | DPCUNIT_CLOCK_GATE_DISABLE); else - I915_WRITE(CG_2D_DIS, - I915_READ(CG_2D_DIS) & (~DPCUNIT_CLOCK_GATE_DISABLE)); + I915_WRITE(DSPCLK_GATE_D, + I915_READ(DSPCLK_GATE_D) & (~DPCUNIT_CLOCK_GATE_DISABLE)); } /* -- cgit v1.2.3-70-g09d2