From 99eb6a01e5ac6cf28aadc64e6ff346939874dfd2 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Mon, 26 Sep 2011 14:29:12 -0700 Subject: [PATCH] drm/i915: Use CK505 as non-SSC source where available When trying to use SSC on Ibex Peak without CK505, any non-SSC outputs (like VGA or TV) get broken. So, do not use SSC on Ibex Peak unless there is a CK505 available (as specified by the VBT). On Cougar Point, all clocking is internal, so SSC can always be used, and there will never be a CK505 available. This eliminates VGA shimmer on some Ironlake machines which have a CK505 clock source. References: https://bugzilla.kernel.org/show_bug.cgi?id=21742 References: https://bugs.freedesktop.org/show_bug.cgi?id=38750 Signed-off-by: Keith Packard Reviewed-by: Chris Wilson --- drivers/gpu/drm/i915/intel_display.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index f99993577168..4c9684c54f18 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5119,6 +5119,8 @@ static void ironlake_update_pch_refclk(struct drm_device *dev) bool has_cpu_edp = false; bool has_pch_edp = false; bool has_panel = false; + bool has_ck505 = false; + bool can_ssc = false; /* We need to take the global config into account */ list_for_each_entry(encoder, &mode_config->encoder_list, @@ -5137,8 +5139,18 @@ static void ironlake_update_pch_refclk(struct drm_device *dev) break; } } - DRM_DEBUG_KMS("has_panel %d has_lvds %d has_pch_edp %d has_cpu_edp %d\n", - has_panel, has_lvds, has_pch_edp, has_cpu_edp); + + if (HAS_PCH_IBX(dev)) { + has_ck505 = dev_priv->display_clock_mode; + can_ssc = has_ck505; + } else { + has_ck505 = false; + can_ssc = true; + } + + DRM_DEBUG_KMS("has_panel %d has_lvds %d has_pch_edp %d has_cpu_edp %d has_ck505 %d\n", + has_panel, has_lvds, has_pch_edp, has_cpu_edp, + has_ck505); /* Ironlake: try to setup display ref clock before DPLL * enabling. This is only under driver's control after @@ -5148,14 +5160,18 @@ static void ironlake_update_pch_refclk(struct drm_device *dev) temp = I915_READ(PCH_DREF_CONTROL); /* Always enable nonspread source */ temp &= ~DREF_NONSPREAD_SOURCE_MASK; - temp |= DREF_NONSPREAD_SOURCE_ENABLE; + + if (has_ck505) + temp |= DREF_NONSPREAD_CK505_ENABLE; + else + temp |= DREF_NONSPREAD_SOURCE_ENABLE; if (has_panel) { temp &= ~DREF_SSC_SOURCE_MASK; temp |= DREF_SSC_SOURCE_ENABLE; /* SSC must be turned on before enabling the CPU output */ - if (intel_panel_use_ssc(dev_priv)) { + if (intel_panel_use_ssc(dev_priv) && can_ssc) { DRM_DEBUG_KMS("Using SSC on panel\n"); temp |= DREF_SSC1_ENABLE; } @@ -5169,7 +5185,7 @@ static void ironlake_update_pch_refclk(struct drm_device *dev) /* Enable CPU source on CPU attached eDP */ if (has_cpu_edp) { - if (intel_panel_use_ssc(dev_priv)) { + if (intel_panel_use_ssc(dev_priv) && can_ssc) { DRM_DEBUG_KMS("Using SSC on eDP\n"); temp |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD; } -- GitLab