public inbox for intel-gfx@lists.freedesktop.org
 help / color / mirror / Atom feed
* [Intel-gfx] [PATCH 1/3] drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg()
@ 2021-01-26 20:08 Juston Li
  2021-01-26 20:08 ` [Intel-gfx] [PATCH 2/3] drm/i915/hdcp: read RxInfo once when reading Send_Pairing_Info Juston Li
                   ` (3 more replies)
  0 siblings, 4 replies; 8+ messages in thread
From: Juston Li @ 2021-01-26 20:08 UTC (permalink / raw)
  To: intel-gfx; +Cc: seanpaul

Update cp_irq_count_cached when we handle reading the messages rather
than writing a message to make sure the value is up to date and not
stale from a previously handled CP_IRQ. AKE flow  doesn't always respond
to a read with a write msg.

E.g. currently AKE_Send_Pairing_Info will "timeout" because we received
a CP_IRQ for reading AKE_Send_H_Prime but no write occurred between that
and reading AKE_Send_Pairing_Info so cp_irq_count_cached is stale
causing the wait to return right away rather than waiting for a new
CP_IRQ.

Signed-off-by: Juston Li <juston.li@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_hdcp.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_hdcp.c b/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
index f372e25edab4..56a1a0ed20fe 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
@@ -442,8 +442,6 @@ static
 int intel_dp_hdcp2_write_msg(struct intel_digital_port *dig_port,
 			     void *buf, size_t size)
 {
-	struct intel_dp *dp = &dig_port->dp;
-	struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
 	unsigned int offset;
 	u8 *byte = buf;
 	ssize_t ret, bytes_to_write, len;
@@ -459,8 +457,6 @@ int intel_dp_hdcp2_write_msg(struct intel_digital_port *dig_port,
 	bytes_to_write = size - 1;
 	byte++;
 
-	hdcp->cp_irq_count_cached = atomic_read(&hdcp->cp_irq_count);
-
 	while (bytes_to_write) {
 		len = bytes_to_write > DP_AUX_MAX_PAYLOAD_BYTES ?
 				DP_AUX_MAX_PAYLOAD_BYTES : bytes_to_write;
@@ -508,6 +504,8 @@ static
 int intel_dp_hdcp2_read_msg(struct intel_digital_port *dig_port,
 			    u8 msg_id, void *buf, size_t size)
 {
+	struct intel_dp *dp = &dig_port->dp;
+	struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
 	unsigned int offset;
 	u8 *byte = buf;
@@ -523,6 +521,8 @@ int intel_dp_hdcp2_read_msg(struct intel_digital_port *dig_port,
 	if (ret < 0)
 		return ret;
 
+	hdcp->cp_irq_count_cached = atomic_read(&hdcp->cp_irq_count);
+
 	if (msg_id == HDCP_2_2_REP_SEND_RECVID_LIST) {
 		ret = get_receiver_id_list_size(dig_port);
 		if (ret < 0)
-- 
2.29.2

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [Intel-gfx] [PATCH 0/3] drm/i915/hdcp: HDCP2.2 MST dock fixes
@ 2021-08-10 21:58 Juston Li
  2021-08-10 21:58 ` [Intel-gfx] [PATCH 1/3] drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg() Juston Li
  0 siblings, 1 reply; 8+ messages in thread
From: Juston Li @ 2021-08-10 21:58 UTC (permalink / raw)
  To: intel-gfx, dri-devel
  Cc: seanpaul, anshuman.gupta, ramalingam.c, rodrigo.vivi, Juston Li

Fixes to get HDCP2.2 over MST working on MST docking stations with
certain behaviors that cause the current flow to fail.
Tested with Dell WD-19 and Lenovo ThinkPad USB Type-C Dock Gen 2.

These fixes should make the flow more robust to handle behaviors that as
far as I can tell are unclear in the HDCP spec:

RxInfo contains repeater topology information needed for MST. The
behavior on these docks is that this can only be read during 
RepeaterAuth_Send_ReceiverID_List when the RxStatus READY bit is set
otherwise the dock will return NACK. It seems these docks treat
reading this range at any other time as invalid when the READY bit
isn't set possibly because it could be stale. The HDCP spec also states
the READY bit is cleared after RxInfo is read.

These fixes address this behavior by only reading RxInfo once during the 
AKE flow and reusing that data.

Juston Li (3):
  drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg()
  drm/i915/hdcp: read RxInfo once when reading
    RepeaterAuth_Send_ReceiverID_List
  drm/i915/hdcp: reuse rx_info for mst stream type1 capability check

 .../drm/i915/display/intel_display_types.h    |  2 +
 drivers/gpu/drm/i915/display/intel_dp_hdcp.c  | 77 +++++--------------
 drivers/gpu/drm/i915/display/intel_hdcp.c     | 47 +++++------
 include/drm/drm_dp_helper.h                   |  2 +-
 4 files changed, 43 insertions(+), 85 deletions(-)

-- 
2.31.1


^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-08-10 21:59 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-01-26 20:08 [Intel-gfx] [PATCH 1/3] drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg() Juston Li
2021-01-26 20:08 ` [Intel-gfx] [PATCH 2/3] drm/i915/hdcp: read RxInfo once when reading Send_Pairing_Info Juston Li
2021-01-26 20:08 ` [Intel-gfx] [PATCH 3/3] drm/i915/hdcp: disable the QSES check for HDCP2.2 over MST Juston Li
2021-01-27  7:39   ` kernel test robot
2021-01-27 23:54   ` kernel test robot
2021-01-26 20:49 ` [Intel-gfx] ✗ Fi.CI.BUILD: failure for series starting with [1/3] drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg() Patchwork
2021-01-27  5:01 ` [Intel-gfx] [PATCH 1/3] " Gupta, Anshuman
  -- strict thread matches above, loose matches on Subject: below --
2021-08-10 21:58 [Intel-gfx] [PATCH 0/3] drm/i915/hdcp: HDCP2.2 MST dock fixes Juston Li
2021-08-10 21:58 ` [Intel-gfx] [PATCH 1/3] drm/i915/hdcp: update cp_irq_count_cached in intel_dp_hdcp2_read_msg() Juston Li

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox