From 0e081d03841ebf257d5a4852f36377340b06309e Mon Sep 17 00:00:00 2001
From: Oliver Barta <oliver.barta@aptiv.com>
Date: Mon, 4 May 2020 14:35:24 +0200
Subject: drm/i915: HDCP: retry link integrity check on failure
Git-commit: b08239b2f47190981309c29149e31f111f699aab
Patch-mainline: v5.9-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
A single Ri mismatch doesn't automatically mean that the link integrity
is broken. Update and check of Ri and Ri' are done asynchronously. In
case an update happens just between the read of Ri' and the check against
Ri there will be a mismatch even if the link integrity is fine otherwise.
Signed-off-by: Oliver Barta <oliver.barta@aptiv.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200504123524.7731-1-oliver.barta@aptiv.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/display/intel_hdmi.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_hdmi.c b/drivers/gpu/drm/i915/display/intel_hdmi.c
index 792549f749d9..ae4ae800e908 100644
--- a/drivers/gpu/drm/i915/display/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/display/intel_hdmi.c
@@ -1540,7 +1540,7 @@ int intel_hdmi_hdcp_toggle_signalling(struct intel_digital_port *intel_dig_port,
}
static
-bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
+bool intel_hdmi_hdcp_check_link_once(struct intel_digital_port *intel_dig_port)
{
struct drm_i915_private *i915 = to_i915(intel_dig_port->base.base.dev);
struct intel_connector *connector =
@@ -1563,8 +1563,7 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
if (wait_for((intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder, port)) &
(HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC)) ==
(HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) {
- drm_err(&i915->drm,
- "Ri' mismatch detected, link check failed (%x)\n",
+ drm_dbg_kms(&i915->drm, "Ri' mismatch detected (%x)\n",
intel_de_read(i915, HDCP_STATUS(i915, cpu_transcoder,
port)));
return false;
@@ -1572,6 +1571,20 @@ bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
return true;
}
+static
+bool intel_hdmi_hdcp_check_link(struct intel_digital_port *intel_dig_port)
+{
+ struct drm_i915_private *i915 = to_i915(intel_dig_port->base.base.dev);
+ int retry;
+
+ for (retry = 0; retry < 3; retry++)
+ if (intel_hdmi_hdcp_check_link_once(intel_dig_port))
+ return true;
+
+ drm_err(&i915->drm, "Link check failed\n");
+ return false;
+}
+
struct hdcp2_hdmi_msg_timeout {
u8 msg_id;
u16 timeout;
--
2.29.2