From: Charlene Liu <Charlene.Liu@amd.com>
Date: Fri, 5 Aug 2022 16:59:47 +0000 (-0400)
Subject: drm/amd/display: avoid doing vm_init multiple time
X-Git-Tag: v5.15.73~571
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=85dd24ff77c15f5fc0e16bc3f288f5d1ac93e02b;p=platform%2Fkernel%2Flinux-rpi.git

drm/amd/display: avoid doing vm_init multiple time

[ Upstream commit 5544a7b5a07480192eb5fd3536462faed2c21528 ]

[why]
this is to ensure that driver will not reprogram hvm_prefetch_req again if
it is done.

Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hubbub.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hubbub.c
index 36044cb..1c0f56d 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hubbub.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_hubbub.c
@@ -67,9 +67,15 @@ static uint32_t convert_and_clamp(
 void dcn21_dchvm_init(struct hubbub *hubbub)
 {
 	struct dcn20_hubbub *hubbub1 = TO_DCN20_HUBBUB(hubbub);
-	uint32_t riommu_active;
+	uint32_t riommu_active, prefetch_done;
 	int i;
 
+	REG_GET(DCHVM_RIOMMU_STAT0, HOSTVM_PREFETCH_DONE, &prefetch_done);
+
+	if (prefetch_done) {
+		hubbub->riommu_active = true;
+		return;
+	}
 	//Init DCHVM block
 	REG_UPDATE(DCHVM_CTRL0, HOSTVM_INIT_REQ, 1);