From: Akash Goel <akash.goel@xxxxxxxxx> For disabling L3 clock gating we need to set bit 25 of MMIO register 940c. Earlier this was being done by just writing 1 into bit 25 and resetting all other bits. This patch modifies the routine to read-modify-write of the register, so that the values of other bits are not destroyed. v2: Modifying the comments and the patch commit message (Chris) Signed-off-by: Akash Goel <akash.goel@xxxxxxxxx> Signed-off-by: Sourab Gupta <sourab.gupta@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_pm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index c3a8554..af4bb8e 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5093,8 +5093,11 @@ static void valleyview_init_clock_gating(struct drm_device *dev) I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE); - /* WaDisableL3Bank2xClockGate:vlv */ - I915_WRITE(GEN7_UCGCTL4, GEN7_L3BANK2X_CLOCK_GATE_DISABLE); + /* WaDisableL3Bank2xClockGate:vlv + * Disabling L3 clock gating- MMIO 940c[25] = 1 + * Set bit 25, to disable L3_BANK_2x_CLK_GATING */ + I915_WRITE(GEN7_UCGCTL4, + I915_READ(GEN7_UCGCTL4) | GEN7_L3BANK2X_CLOCK_GATE_DISABLE); I915_WRITE(MI_ARB_VLV, MI_ARB_DISPLAY_TRICKLE_FEED_DISABLE); -- 1.8.5.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx