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<pre wrap="">Acked-by: Hui Wang <a class="moz-txt-link-rfc2396E" href="mailto:hui.wang@canonical.com"><hui.wang@canonical.com></a></pre>
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On 2018年03月28日 11:20, AceLan Kao wrote:<br>
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cite="mid:1522207258-10046-1-git-send-email-acelan.kao@canonical.com">
<pre wrap="">BugLink: <a class="moz-txt-link-freetext" href="https://launchpad.net/bugs/1759188">https://launchpad.net/bugs/1759188</a>
[Impact]
The display becomes blank after S3 with the following error messages.
[ 38.304449] [drm:gmbus_xfer [i915]] GMBUS [i915 gmbus dpd] NAK for addr: 0050 w(1)
[ 38.304462] [drm:gmbus_xfer [i915]] GMBUS [i915 gmbus dpd] NAK on first message, retry
[ 38.306726] [drm:gmbus_xfer [i915]] GMBUS [i915 gmbus dpd] NAK for addr: 0050 w(1)
[ 38.306733] [drm:drm_do_probe_ddc_edid [drm]] drm: skipping non-existent adapter i915 gmbus dpd
[ 38.311251] [drm:drm_dp_dual_mode_detect [drm_kms_helper]] DP dual mode HDMI ID: DP-HDMI ADAPTOR\004 (err 0)
[ 38.313538] [drm:drm_dp_dual_mode_detect [drm_kms_helper]] DP dual mode adaptor ID: 44 (err 0)
[ 38.313554] [drm:intel_hdmi_set_edid [i915]] DP dual mode adaptor (type 1 HDMI) detected (max TMDS clock: 165000 kHz)
[ 38.313557] [drm:drm_helper_hpd_irq_event [drm_kms_helper]] [CONNECTOR:115:HDMI-A-1] status updated from disconnected to disconnected
[Fix]
This commit pointed out by Timo fixes the issue.
[Regression Potential]
Should be low, although the change applies broadly.
>From the patch description, it explains why it should be safe.
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<pre wrap="">This workaround was designed to minimize the impact only
to save the bad case with that link rates. But HW engineers
indicated that it should be safe to apply broadly, although
they were expecting the DPLL0 link rate to be unchanged on
runtime.
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<pre wrap="">
Lucas De Marchi (1):
drm/i915: Apply Display WA #1183 on skl, kbl, and cfl
drivers/gpu/drm/i915/i915_reg.h | 2 ++
drivers/gpu/drm/i915/intel_cdclk.c | 35 ++++++++++++++++++++++++---------
drivers/gpu/drm/i915/intel_runtime_pm.c | 10 ++++++++++
3 files changed, 38 insertions(+), 9 deletions(-)
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