From: Chris Park <chris.park@amd.com>
Date: Tue, 28 May 2024 19:56:22 +0000 (-0400)
Subject: drm/amd/display: Avoid programming DTO if Refclk is 0
X-Git-Tag: v6.11-rc1~141^2~18^2~94
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d3d996ec8905a0098f160d7a4dcca2b54d48d697;p=thirdparty%2Fkernel%2Flinux.git

drm/amd/display: Avoid programming DTO if Refclk is 0

[Why]
Reference clock, either DPREFCLK or DTBCLK can be a value of 0
which then will encounter division by 0.

[How]
Avoid further calculation and programming if refclk is not
populated.

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Signed-off-by: Chris Park <chris.park@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/amd/display/dc/dccg/dcn401/dcn401_dccg.c b/drivers/gpu/drm/amd/display/dc/dccg/dcn401/dcn401_dccg.c
index 3538e190f2175..dac31c4cf2a78 100644
--- a/drivers/gpu/drm/amd/display/dc/dccg/dcn401/dcn401_dccg.c
+++ b/drivers/gpu/drm/amd/display/dc/dccg/dcn401/dcn401_dccg.c
@@ -603,6 +603,10 @@ static void dccg401_set_dp_dto(
 		BREAK_TO_DEBUGGER();
 		return;
 	}
+	if (!params->refclk_hz) {
+		BREAK_TO_DEBUGGER();
+		return;
+	}
 
 	if (!dc_is_tmds_signal(params->signal)) {
 		uint64_t dto_integer;