Attachment 119190 Details for Bug 91791 – Test purpose for disabling DP MST for DP HUB in SKL platform

Test purpose for disabling DP MST for DP HUB in SKL platform

0001-drm-i915-skl-not-enter-MST-mode-during-DP-probing-fo.patch (text/plain), 1.53 KB, created by Gary Wang on 2015-10-26 01:36:34 UTC

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Creator: Gary Wang

Created: 2015-10-26 01:36:34 UTC

Size: 1.53 KB

patch

obsolete

>From 3ae1479c93219f220ce1769d693191943b24ce00 Mon Sep 17 00:00:00 2001
>From: Gary Wang <gary.c.wang@intel.com>
>Date: Mon, 26 Oct 2015 09:20:54 +0800
>Subject: [PATCH] drm/i915/skl: not enter MST mode during DP probing for
> DisplayPort MST-enabled Hub
>
>It found some DP MST-enabled hub causing problem of DP link computation in SKL-U,
>and need to disable its MST support.
>
>This is a workaround, and need to be fixed further.
>
>References: https://bugs.freedesktop.org/show_bug.cgi?id=91791
>
>Signed-off-by: Gary Wang <gary.c.wang@intel.com>
>---
> drivers/gpu/drm/i915/intel_dp.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
> mode change 100644 => 100755 drivers/gpu/drm/i915/intel_dp.c
>
>diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>old mode 100644
>new mode 100755
>index 8287df4..ad1e908
>--- a/drivers/gpu/drm/i915/intel_dp.c
>+++ b/drivers/gpu/drm/i915/intel_dp.c
>@@ -4081,12 +4081,16 @@ intel_dp_probe_oui(struct intel_dp *intel_dp)
> static bool
> intel_dp_probe_mst(struct intel_dp *intel_dp)
> {
>+	struct drm_device *dev = intel_dp_to_dev(intel_dp);
> 	u8 buf[1];
> 
> 	if (!intel_dp->can_mst)
> 		return false;
> 
>-	if (intel_dp->dpcd[DP_DPCD_REV] < 0x12)
>+	//TO-DO, this is workaround for test purpose only on disabling DP 1.2 MST
>+	//SKL-U suffers error from DP data link computation with DP MST enabled.
>+	//fix-BUG https://bugs.freedesktop.org/show_bug.cgi?id=91791
>+	if (intel_dp->dpcd[DP_DPCD_REV] < 0x12 || IS_SKYLAKE(dev))
> 		return false;
> 
> 	if (intel_dp_dpcd_read_wake(&intel_dp->aux, DP_MSTM_CAP, buf, 1)) {
>-- 
>1.9.1
>

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Attachments on bug 91791: 118977 | 119067 | 119128 | 119131 | 119133 | 119190 | 119197 | 119332 | 119496 | 119556 | 124179 | 124180 | 124181

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