[PATCH 02/20] drm/amd/display: Fix DMUB reset sequence for DCN32

[waynelin <Wayne.Lin@amd.com>]

From: Dillon Varone <Dillon.Varone@amd.com>

[WHY&HOW]
Backport reset sequence fixes implemented on DCN401 to DCN32 to address
stability issues when resetting the DMUB.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Dillon Varone <Dillon.Varone@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
---
 .../gpu/drm/amd/display/dmub/src/dmub_dcn32.c | 50 ++++++++++++-------
 .../drm/amd/display/dmub/src/dmub_dcn401.c    | 17 +++++--
 2 files changed, 45 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn32.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn32.c
index ce041f6239dc..7e9856289910 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn32.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn32.c
@@ -89,50 +89,58 @@ static inline void dmub_dcn32_translate_addr(const union dmub_addr *addr_in,
 void dmub_dcn32_reset(struct dmub_srv *dmub)
 {
 	union dmub_gpint_data_register cmd;
-	const uint32_t timeout = 100000;
-	uint32_t in_reset, is_enabled, scratch, i, pwait_mode;
+	const uint32_t timeout_us = 1 * 1000 * 1000; //1s
+	const uint32_t poll_delay_us = 1; //1us
+	uint32_t i = 0;
+	uint32_t enabled, in_reset, scratch, pwait_mode;
 
-	REG_GET(DMCUB_CNTL2, DMCUB_SOFT_RESET, &in_reset);
-	REG_GET(DMCUB_CNTL, DMCUB_ENABLE, &is_enabled);
+	REG_GET(DMCUB_CNTL,
+			DMCUB_ENABLE, &enabled);
+	REG_GET(DMCUB_CNTL2,
+			DMCUB_SOFT_RESET, &in_reset);
 
-	if (in_reset == 0 && is_enabled != 0) {
+	if (enabled && in_reset == 0) {
 		cmd.bits.status = 1;
 		cmd.bits.command_code = DMUB_GPINT__STOP_FW;
 		cmd.bits.param = 0;
 
 		dmub->hw_funcs.set_gpint(dmub, cmd);
 
-		for (i = 0; i < timeout; ++i) {
-			if (dmub->hw_funcs.is_gpint_acked(dmub, cmd))
-				break;
-
-			udelay(1);
-		}
-
-		for (i = 0; i < timeout; ++i) {
+		for (; i < timeout_us; i++) {
 			scratch = REG_READ(DMCUB_SCRATCH7);
 			if (scratch == DMUB_GPINT__STOP_FW_RESPONSE)
 				break;
 
-			udelay(1);
+			udelay(poll_delay_us);
 		}
 
-		for (i = 0; i < timeout; ++i) {
+		for (; i < timeout_us; i++) {
 			REG_GET(DMCUB_CNTL, DMCUB_PWAIT_MODE_STATUS, &pwait_mode);
 			if (pwait_mode & (1 << 0))
 				break;
 
-			udelay(1);
+			udelay(poll_delay_us);
 		}
-		/* Force reset in case we timed out, DMCUB is likely hung. */
 	}
 
-	if (is_enabled) {
+	if (enabled) {
 		REG_UPDATE(DMCUB_CNTL2, DMCUB_SOFT_RESET, 1);
 		udelay(1);
 		REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
 	}
 
+	if (i >= timeout_us) {
+		/* timeout should never occur */
+		BREAK_TO_DEBUGGER();
+	}
+
+	REG_UPDATE(DMCUB_REGION3_CW2_TOP_ADDRESS, DMCUB_REGION3_CW2_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW3_TOP_ADDRESS, DMCUB_REGION3_CW3_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW4_TOP_ADDRESS, DMCUB_REGION3_CW4_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW5_TOP_ADDRESS, DMCUB_REGION3_CW5_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW6_TOP_ADDRESS, DMCUB_REGION3_CW6_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW7_TOP_ADDRESS, DMCUB_REGION3_CW7_ENABLE, 0);
+
 	REG_WRITE(DMCUB_INBOX1_RPTR, 0);
 	REG_WRITE(DMCUB_INBOX1_WPTR, 0);
 	REG_WRITE(DMCUB_OUTBOX1_RPTR, 0);
@@ -141,7 +149,7 @@ void dmub_dcn32_reset(struct dmub_srv *dmub)
 	REG_WRITE(DMCUB_OUTBOX0_WPTR, 0);
 	REG_WRITE(DMCUB_SCRATCH0, 0);
 
-	/* Clear the GPINT command manually so we don't send anything during boot. */
+	/* Clear the GPINT command manually so we don't reset again. */
 	cmd.all = 0;
 	dmub->hw_funcs.set_gpint(dmub, cmd);
 }
@@ -163,7 +171,9 @@ void dmub_dcn32_backdoor_load(struct dmub_srv *dmub,
 
 	dmub_dcn32_get_fb_base_offset(dmub, &fb_base, &fb_offset);
 
+	/* reset and disable DMCUB and MMHUBBUB DMUIF */
 	REG_UPDATE(DMCUB_SEC_CNTL, DMCUB_SEC_RESET, 1);
+	REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
 
 	dmub_dcn32_translate_addr(&cw0->offset, fb_base, fb_offset, &offset);
 
@@ -193,7 +203,9 @@ void dmub_dcn32_backdoor_load_zfb_mode(struct dmub_srv *dmub,
 {
 	union dmub_addr offset;
 
+	/* reset and disable DMCUB and MMHUBBUB DMUIF */
 	REG_UPDATE(DMCUB_SEC_CNTL, DMCUB_SEC_RESET, 1);
+	REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
 
 	offset = cw0->offset;
 
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
index b31adbd0d685..95542299e3b3 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
@@ -81,7 +81,7 @@ void dmub_dcn401_reset(struct dmub_srv *dmub)
 		dmub->hw_funcs.set_gpint(dmub, cmd);
 
 		for (; i < timeout_us; i++) {
-			scratch = dmub->hw_funcs.get_gpint_response(dmub);
+			scratch = REG_READ(DMCUB_SCRATCH7);
 			if (scratch == DMUB_GPINT__STOP_FW_RESPONSE)
 				break;
 
@@ -97,11 +97,24 @@ void dmub_dcn401_reset(struct dmub_srv *dmub)
 		}
 	}
 
+	if (enabled) {
+		REG_UPDATE(DMCUB_CNTL2, DMCUB_SOFT_RESET, 1);
+		udelay(1);
+		REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
+	}
+
 	if (i >= timeout_us) {
 		/* timeout should never occur */
 		BREAK_TO_DEBUGGER();
 	}
 
+	REG_UPDATE(DMCUB_REGION3_CW2_TOP_ADDRESS, DMCUB_REGION3_CW2_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW3_TOP_ADDRESS, DMCUB_REGION3_CW3_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW4_TOP_ADDRESS, DMCUB_REGION3_CW4_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW5_TOP_ADDRESS, DMCUB_REGION3_CW5_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW6_TOP_ADDRESS, DMCUB_REGION3_CW6_ENABLE, 0);
+	REG_UPDATE(DMCUB_REGION3_CW7_TOP_ADDRESS, DMCUB_REGION3_CW7_ENABLE, 0);
+
 	REG_WRITE(DMCUB_INBOX1_RPTR, 0);
 	REG_WRITE(DMCUB_INBOX1_WPTR, 0);
 	REG_WRITE(DMCUB_OUTBOX1_RPTR, 0);
@@ -134,7 +147,6 @@ void dmub_dcn401_backdoor_load(struct dmub_srv *dmub,
 
 	/* reset and disable DMCUB and MMHUBBUB DMUIF */
 	REG_UPDATE(DMCUB_SEC_CNTL, DMCUB_SEC_RESET, 1);
-	REG_UPDATE(MMHUBBUB_SOFT_RESET, DMUIF_SOFT_RESET, 1);
 	REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
 
 	dmub_dcn401_translate_addr(&cw0->offset, fb_base, fb_offset, &offset);
@@ -168,7 +180,6 @@ void dmub_dcn401_backdoor_load_zfb_mode(struct dmub_srv *dmub,
 
 	/* reset and disable DMCUB and MMHUBBUB DMUIF */
 	REG_UPDATE(DMCUB_SEC_CNTL, DMCUB_SEC_RESET, 1);
-	REG_UPDATE(MMHUBBUB_SOFT_RESET, DMUIF_SOFT_RESET, 1);
 	REG_UPDATE(DMCUB_CNTL, DMCUB_ENABLE, 0);
 
 	offset = cw0->offset;
-- 
2.43.0