From: Paulo Zanoni Date: Tue, 20 Nov 2012 15:27:40 +0000 (-0200) Subject: drm/i915: don't intel_crt_init if DDI A has 4 lanes X-Git-Tag: firefly_0821_release~3680^2~1036^2~40^2~119 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=79935fca3f1259e0a6fe203b55008f84ab8f3087;p=firefly-linux-kernel-4.4.55.git drm/i915: don't intel_crt_init if DDI A has 4 lanes DDI A and E have 4 lanes to share, so if DDI A is using 4 lanes, there's nothing left for DDI E, which means there's no CRT port on the machine. The bit we're checking here is programmed at system boot and it cannot be changed afterwards, so we cannot change the amount of lanes reserved for each DDI port. Signed-off-by: Paulo Zanoni Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 2d838766418b..5aba146300d3 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -4515,6 +4515,7 @@ #define DDI_BUF_EMP_800MV_3_5DB_HSW (8<<24) /* Sel8 */ #define DDI_BUF_EMP_MASK (0xf<<24) #define DDI_BUF_IS_IDLE (1<<7) +#define DDI_A_4_LANES (1<<4) #define DDI_PORT_WIDTH_X1 (0<<1) #define DDI_PORT_WIDTH_X2 (1<<1) #define DDI_PORT_WIDTH_X4 (3<<1) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 4e303cf7ead6..e233541d4c9f 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -8267,7 +8267,9 @@ static void intel_setup_outputs(struct drm_device *dev) I915_WRITE(PFIT_CONTROL, 0); } - intel_crt_init(dev); + if (!(IS_HASWELL(dev) && + (I915_READ(DDI_BUF_CTL(PORT_A)) & DDI_A_4_LANES))) + intel_crt_init(dev); if (IS_HASWELL(dev)) { int found;