From: jsg <jsg@openbsd.org>
Date: Thu, 24 Aug 2023 06:07:04 +0000 (+0000)
Subject: drm/amd/display: Skip DPP DTO update if root clock is gated
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=427e448f9edb6a17acccec0b916a1d84ef8dd88d;p=openbsd

drm/amd/display: Skip DPP DTO update if root clock is gated

From Nicholas Kazlauskas
5447155001e6aa30d55b06a5b4ff799fd3a1f51d in linux-6.1.y/6.1.47
30f90f3c1c2c63c2fa44f61233737d27b72637c2 in mainline linux
---

diff --git a/sys/dev/pci/drm/amd/display/dc/dcn31/dcn31_dccg.c b/sys/dev/pci/drm/amd/display/dc/dcn31/dcn31_dccg.c
index 7d2b982506f..cef32a1f91c 100644
--- a/sys/dev/pci/drm/amd/display/dc/dcn31/dcn31_dccg.c
+++ b/sys/dev/pci/drm/amd/display/dc/dcn31/dcn31_dccg.c
@@ -47,6 +47,14 @@ void dccg31_update_dpp_dto(struct dccg *dccg, int dpp_inst, int req_dppclk)
 {
 	struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
 
+	if (dccg->dpp_clock_gated[dpp_inst]) {
+		/*
+		 * Do not update the DPPCLK DTO if the clock is stopped.
+		 * It is treated the same as if the pipe itself were in PG.
+		 */
+		return;
+	}
+
 	if (dccg->ref_dppclk && req_dppclk) {
 		int ref_dppclk = dccg->ref_dppclk;
 		int modulo, phase;
diff --git a/sys/dev/pci/drm/amd/display/dc/dcn314/dcn314_dccg.c b/sys/dev/pci/drm/amd/display/dc/dcn314/dcn314_dccg.c
index 85ea3334355..97c6a79dfba 100644
--- a/sys/dev/pci/drm/amd/display/dc/dcn314/dcn314_dccg.c
+++ b/sys/dev/pci/drm/amd/display/dc/dcn314/dcn314_dccg.c
@@ -296,6 +296,9 @@ static void dccg314_dpp_root_clock_control(
 {
 	struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
 
+	if (dccg->dpp_clock_gated[dpp_inst] == clock_on)
+		return;
+
 	if (clock_on) {
 		/* turn off the DTO and leave phase/modulo at max */
 		REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_ENABLE[dpp_inst], 0);
@@ -309,6 +312,8 @@ static void dccg314_dpp_root_clock_control(
 			  DPPCLK0_DTO_PHASE, 0,
 			  DPPCLK0_DTO_MODULO, 1);
 	}
+
+	dccg->dpp_clock_gated[dpp_inst] = !clock_on;
 }
 
 static const struct dccg_funcs dccg314_funcs = {
diff --git a/sys/dev/pci/drm/amd/display/dc/inc/hw/dccg.h b/sys/dev/pci/drm/amd/display/dc/inc/hw/dccg.h
index ad6acd1b34e..9651cccb084 100644
--- a/sys/dev/pci/drm/amd/display/dc/inc/hw/dccg.h
+++ b/sys/dev/pci/drm/amd/display/dc/inc/hw/dccg.h
@@ -68,6 +68,7 @@ struct dccg {
 	const struct dccg_funcs *funcs;
 	int pipe_dppclk_khz[MAX_PIPES];
 	int ref_dppclk;
+	bool dpp_clock_gated[MAX_PIPES];
 	//int dtbclk_khz[MAX_PIPES];/* TODO needs to be removed */
 	//int audio_dtbclk_khz;/* TODO needs to be removed */
 	//int ref_dtbclk_khz;/* TODO needs to be removed */