From 043029655816ed4cfc2ed247020ef97e5d637392 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Mon, 24 Aug 2009 10:25:23 +0800 Subject: [PATCH] drm/i915: Support IGD EOS In the event that any one of the DAC analog outputs (R,G,B) were driven at full-scale (white video) or some analog level close to full-scale voltage, and if the video cable were then disconnected, the analog video voltage level would exceed the maximum electrical overstress limit of the native (thin-oxide) transistors thus causing a long-term reliability concern. The electrical overstress condition occurs in this particular case. This patch address the IGD EOS (electrical overstress condition) issue. When the EOS interrupt occurs, OS should disable DAC and then disable EOS, then the normal hotplug operation follows. TODO: it appears the normal unplug interrupt is missed as reported by Li Peng, need more checks here. Signed-off-by: Shaohua Li Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/i915_irq.c | 21 +++++++++++++++++++++ drivers/gpu/drm/i915/i915_reg.h | 2 ++ drivers/gpu/drm/i915/intel_crt.c | 28 ++++++++++++++++++++++++++++ 3 files changed, 51 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 7ebc84c2881e..6c89f2ff2495 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -565,6 +565,27 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS) I915_WRITE(PORT_HOTPLUG_STAT, hotplug_status); I915_READ(PORT_HOTPLUG_STAT); + + /* EOS interrupts occurs */ + if (IS_IGD(dev) && + (hotplug_status & CRT_EOS_INT_STATUS)) { + u32 temp; + + DRM_DEBUG("EOS interrupt occurs\n"); + /* status is already cleared */ + temp = I915_READ(ADPA); + temp &= ~ADPA_DAC_ENABLE; + I915_WRITE(ADPA, temp); + + temp = I915_READ(PORT_HOTPLUG_EN); + temp &= ~CRT_EOS_INT_EN; + I915_WRITE(PORT_HOTPLUG_EN, temp); + + temp = I915_READ(PORT_HOTPLUG_STAT); + if (temp & CRT_EOS_INT_STATUS) + I915_WRITE(PORT_HOTPLUG_STAT, + CRT_EOS_INT_STATUS); + } } I915_WRITE(IIR, iir); diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 2955083aa471..87a737ff3d72 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -683,6 +683,7 @@ #define SDVOB_HOTPLUG_INT_EN (1 << 26) #define SDVOC_HOTPLUG_INT_EN (1 << 25) #define TV_HOTPLUG_INT_EN (1 << 18) +#define CRT_EOS_INT_EN (1 << 10) #define CRT_HOTPLUG_INT_EN (1 << 9) #define CRT_HOTPLUG_FORCE_DETECT (1 << 3) #define CRT_HOTPLUG_ACTIVATION_PERIOD_32 (0 << 8) @@ -717,6 +718,7 @@ #define DPC_HOTPLUG_INT_STATUS (1 << 28) #define HDMID_HOTPLUG_INT_STATUS (1 << 27) #define DPD_HOTPLUG_INT_STATUS (1 << 27) +#define CRT_EOS_INT_STATUS (1 << 12) #define CRT_HOTPLUG_INT_STATUS (1 << 11) #define TV_HOTPLUG_INT_STATUS (1 << 10) #define CRT_HOTPLUG_MONITOR_MASK (3 << 8) diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index 590f81c8f594..88814fa2dfd2 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -64,6 +64,34 @@ static void intel_crt_dpms(struct drm_encoder *encoder, int mode) } I915_WRITE(reg, temp); + + if (IS_IGD(dev)) { + if (mode == DRM_MODE_DPMS_OFF) { + /* turn off DAC */ + temp = I915_READ(PORT_HOTPLUG_EN); + temp &= ~CRT_EOS_INT_EN; + I915_WRITE(PORT_HOTPLUG_EN, temp); + + temp = I915_READ(PORT_HOTPLUG_STAT); + if (temp & CRT_EOS_INT_STATUS) + I915_WRITE(PORT_HOTPLUG_STAT, + CRT_EOS_INT_STATUS); + } else { + /* turn on DAC. EOS interrupt must be enabled after DAC + * is enabled, so it sounds not good to enable it in + * i915_driver_irq_postinstall() + * wait 12.5ms after DAC is enabled + */ + msleep(13); + temp = I915_READ(PORT_HOTPLUG_STAT); + if (temp & CRT_EOS_INT_STATUS) + I915_WRITE(PORT_HOTPLUG_STAT, + CRT_EOS_INT_STATUS); + temp = I915_READ(PORT_HOTPLUG_EN); + temp |= CRT_EOS_INT_EN; + I915_WRITE(PORT_HOTPLUG_EN, temp); + } + } } static int intel_crt_mode_valid(struct drm_connector *connector, -- 2.11.0