From: Anthony Koo <Anthony.Koo@amd.com>
Date: Tue, 17 Jul 2018 09:43:44 -0400
Subject: drm/amd/display: Prevent PSR from being enabled if initialization
 fails
Git-commit: 9907704174e0ad4ed02766fac4049971e583323d
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

[Why]
PSR_SET command is sent to the microcontroller in order to initialize
parameters needed for PSR feature, such as telling the microcontroller
which pipe is driving the PSR supported panel. When this command is
skipped or fails, the microcontroller may program the wrong thing if
driver tries to enable PSR.

[How]
If PSR_SET fails, do not set psr_enable flag to indicate the feature is
not yet initialized.

Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c |   38 +++++++++++++++-----------
 drivers/gpu/drm/amd/display/dc/inc/hw/dmcu.h  |    2 -
 2 files changed, 24 insertions(+), 16 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c
@@ -150,7 +150,7 @@ static void dce_dmcu_set_psr_enable(stru
 	}
 }
 
-static void dce_dmcu_setup_psr(struct dmcu *dmcu,
+static bool dce_dmcu_setup_psr(struct dmcu *dmcu,
 		struct dc_link *link,
 		struct psr_context *psr_context)
 {
@@ -261,6 +261,8 @@ static void dce_dmcu_setup_psr(struct dm
 
 	/* notifyDMCUMsg */
 	REG_UPDATE(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 1);
+
+	return true;
 }
 
 static bool dce_is_dmcu_initialized(struct dmcu *dmcu)
@@ -545,24 +547,25 @@ static void dcn10_dmcu_set_psr_enable(st
 	 *  least a few frames. Should never hit the max retry assert below.
 	 */
 	if (wait == true) {
-	for (retryCount = 0; retryCount <= 1000; retryCount++) {
-		dcn10_get_dmcu_psr_state(dmcu, &psr_state);
-		if (enable) {
-			if (psr_state != 0)
-				break;
-		} else {
-			if (psr_state == 0)
-				break;
+		for (retryCount = 0; retryCount <= 1000; retryCount++) {
+			dcn10_get_dmcu_psr_state(dmcu, &psr_state);
+			if (enable) {
+				if (psr_state != 0)
+					break;
+			} else {
+				if (psr_state == 0)
+					break;
+			}
+			udelay(500);
 		}
-		udelay(500);
-	}
 
-	/* assert if max retry hit */
-	ASSERT(retryCount <= 1000);
+		/* assert if max retry hit */
+		if (retryCount >= 1000)
+			ASSERT(0);
 	}
 }
 
-static void dcn10_dmcu_setup_psr(struct dmcu *dmcu,
+static bool dcn10_dmcu_setup_psr(struct dmcu *dmcu,
 		struct dc_link *link,
 		struct psr_context *psr_context)
 {
@@ -577,7 +580,7 @@ static void dcn10_dmcu_setup_psr(struct
 
 	/* If microcontroller is not running, do nothing */
 	if (dmcu->dmcu_state != DMCU_RUNNING)
-		return;
+		return false;
 
 	link->link_enc->funcs->psr_program_dp_dphy_fast_training(link->link_enc,
 			psr_context->psrExitLinkTrainingRequired);
@@ -677,6 +680,11 @@ static void dcn10_dmcu_setup_psr(struct
 
 	/* notifyDMCUMsg */
 	REG_UPDATE(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 1);
+
+	/* waitDMCUReadyForCmd */
+	REG_WAIT(MASTER_COMM_CNTL_REG, MASTER_COMM_INTERRUPT, 0, 1, 10000);
+
+	return true;
 }
 
 static void dcn10_psr_wait_loop(
--- a/drivers/gpu/drm/amd/display/dc/inc/hw/dmcu.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/hw/dmcu.h
@@ -48,7 +48,7 @@ struct dmcu_funcs {
 			const char *src,
 			unsigned int bytes);
 	void (*set_psr_enable)(struct dmcu *dmcu, bool enable, bool wait);
-	void (*setup_psr)(struct dmcu *dmcu,
+	bool (*setup_psr)(struct dmcu *dmcu,
 			struct dc_link *link,
 			struct psr_context *psr_context);
 	void (*get_psr_state)(struct dmcu *dmcu, uint32_t *psr_state);