From cba0270924c7a6be1f30abd854ebdb3e0df6fb81 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Mon, 4 Jan 2010 16:29:30 +0800 Subject: [PATCH] drm/i915: Enable/disable the dithering for LVDS based on VBT setting commit 898822ce9561ab9b58a7eb60580a162a83dadecd upstream. Enable/disable the dithering for LVDS based on VBT setting. On the 965/g4x platform the dithering flag is defined in LVDS register. And on the ironlake the dithering flag is defined in pipeconf register. Signed-off-by: Zhao Yakui Signed-off-by: Eric Anholt Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/i915_reg.h | 4 ++++ drivers/gpu/drm/i915/intel_display.c | 15 ++++++++++++++- 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 1687edf68795..54e5907723d7 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -968,6 +968,8 @@ #define LVDS_PORT_EN (1 << 31) /* Selects pipe B for LVDS data. Must be set on pre-965. */ #define LVDS_PIPEB_SELECT (1 << 30) +/* LVDS dithering flag on 965/g4x platform */ +#define LVDS_ENABLE_DITHER (1 << 25) /* Enable border for unscaled (or aspect-scaled) display */ #define LVDS_BORDER_ENABLE (1 << 15) /* @@ -1737,6 +1739,8 @@ /* Display & cursor control */ +/* dithering flag on Ironlake */ +#define PIPE_ENABLE_DITHER (1 << 4) /* Pipe A */ #define PIPEADSL 0x70000 #define PIPEACONF 0x70008 diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index f1de53b2f49b..2e7e521ac4da 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3104,7 +3104,20 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc, * appropriately here, but we need to look more thoroughly into how * panels behave in the two modes. */ - + /* set the dithering flag */ + if (IS_I965G(dev)) { + if (dev_priv->lvds_dither) { + if (IS_IGDNG(dev)) + pipeconf |= PIPE_ENABLE_DITHER; + else + lvds |= LVDS_ENABLE_DITHER; + } else { + if (IS_IGDNG(dev)) + pipeconf &= ~PIPE_ENABLE_DITHER; + else + lvds &= ~LVDS_ENABLE_DITHER; + } + } I915_WRITE(lvds_reg, lvds); I915_READ(lvds_reg); } -- 2.39.2