On 06/25/2018 03:33 AM, Imre Deak wrote:
On Wed, Jun 13, 2018 at 02:48:49PM -0700, clinton.a.taylor@xxxxxxxxx wrote:
From: Clint Taylor <clinton.a.taylor@xxxxxxxxx>
On GLK NUC platforms the HDMI retiming buffer needs additional disabled
time to correctly sync to a faster incoming signal.
When measured on a scope the highspeed lines of the HDMI clock turn off
for ~400uS during a normal resolution change. The HDMI retimer on the
GLK NUC appears to require at least a full frame of quiet time before a
new faster clock can be correctly sync'd. The worst case scenario appears
to be 23.98Hz modes which requires a wait of 41.25ms. Add a quirk to the
driver for GLK NUC that waits 42ms.
V2: Add more devices to the quirk list
Cc: Imre Deak <imre.deak@xxxxxxxxx>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105887
Signed-off-by: Clint Taylor <clinton.a.taylor@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/intel_ddi.c | 8 ++++++++
drivers/gpu/drm/i915/intel_display.c | 19 +++++++++++++++++++
3 files changed, 28 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index be8c2f0..da196b4 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -656,6 +656,7 @@ enum intel_sbi_destination {
#define QUIRK_BACKLIGHT_PRESENT (1<<3)
#define QUIRK_PIN_SWIZZLED_PAGES (1<<5)
#define QUIRK_INCREASE_T12_DELAY (1<<6)
+#define QUIRK_INCREASE_DDI_DISABLED_TIME (1<<7)
struct intel_fbdev;
struct intel_fbc_work;
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index ca73387..bc3d012 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -1791,6 +1791,9 @@ void intel_ddi_enable_transcoder_func(const struct intel_crtc_state *crtc_state)
I915_WRITE(TRANS_DDI_FUNC_CTL(cpu_transcoder), temp);
}
+/* Quirk time computed based on 24fps frame time of 41.25ms */
+#define DDI_DISABLED_QUIRK_TIME 42
+
void intel_ddi_disable_transcoder_func(struct drm_i915_private *dev_priv,
enum transcoder cpu_transcoder)
{
@@ -1800,6 +1803,11 @@ void intel_ddi_disable_transcoder_func(struct drm_i915_private *dev_priv,
val &= ~(TRANS_DDI_FUNC_ENABLE | TRANS_DDI_PORT_MASK | TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
val |= TRANS_DDI_PORT_NONE;
I915_WRITE(reg, val);
+
+ if (dev_priv->quirks & QUIRK_INCREASE_DDI_DISABLED_TIME) {
+ msleep(DDI_DISABLED_QUIRK_TIME);
+ DRM_DEBUG_KMS("Quirk Increase DDI disabled time\n");
No need for the define or the debug message here imo. msleep() can be
inaccurate (even sleeping less than expected), so I'd use a bigger
margin, sleeping say 100ms.
Easy to do and I can submit v3.
If the problem is with the HDMI retimer chip, we should limit the quirk
to HDMI outputs.
Output type is not available in intel_disable_ddi() and I would prefer
not to change the interface only for the quirk. I could move the quirk
execution up a level to haswell_crtc_disable() and detect the
old_crtc_state->type before executing the quirk. However, the quirk is
only being detected for certain boards that only have HDMI outputs.
Unless more boards are added to the quirk_list[] we really don't need
logic to detect HDMI outputs.
-Clint
+ }
}
int intel_ddi_toggle_hdcp_signalling(struct intel_encoder *intel_encoder,
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8251e18..40e0306 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -14749,6 +14749,17 @@ static void quirk_increase_t12_delay(struct drm_device *dev)
DRM_INFO("Applying T12 delay quirk\n");
}
+/* GeminiLake NUC HDMI outputs require additional off time
+ * this allows the onboard retimer to correctly sync to signal
+ */
+static void quirk_increase_ddi_disabled_time(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = to_i915(dev);
+
+ dev_priv->quirks |= QUIRK_INCREASE_DDI_DISABLED_TIME;
+ DRM_INFO("Applying Increase DDI Disabled quirk\n");
+}
+
struct intel_quirk {
int device;
int subsystem_vendor;
@@ -14835,6 +14846,14 @@ static int intel_dmi_reverse_brightness(const struct dmi_system_id *id)
/* Toshiba Satellite P50-C-18C */
{ 0x191B, 0x1179, 0xF840, quirk_increase_t12_delay },
+
+ /* GeminiLake NUC */
+ { 0x3185, 0x8086, 0x2072, quirk_increase_ddi_disabled_time },
+ { 0x3184, 0x8086, 0x2072, quirk_increase_ddi_disabled_time },
+ /* ASRock ITX*/
+ { 0x3185, 0x1849, 0x2212, quirk_increase_ddi_disabled_time },
+ { 0x3184, 0x1849, 0x2212, quirk_increase_ddi_disabled_time },
+
Extra w/s. A quirk list looks ok for now since we can't identify the
retimer chip in any other way.
};
static void intel_init_quirks(struct drm_device *dev)
--
1.9.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
