[PATCH AUTOSEL 6.1 16/29] drm/amd/display: increased min_dcfclk_mhz and min_fclk_mhz

Sasha Levin
2024-02-07T21:25:39Z

From: Sohaib Nadeem <sohaib.nadeem@amd.com>

[ Upstream commit 2ff33c759a4247c84ec0b7815f1f223e155ba82a ]

[why]
Originally, PMFW said min FCLK is 300Mhz, but min DCFCLK can be increased
to 400Mhz because min FCLK is now 600Mhz so FCLK >= 1.5 * DCFCLK hardware
requirement will still be satisfied. Increasing min DCFCLK addresses
underflow issues (underflow occurs when phantom pipe is turned on for some
Sub-Viewport configs).

[how]
Increasing DCFCLK by raising the min_dcfclk_mhz

Reviewed-by: Chaitanya Dhere <chaitanya.dhere@amd.com>
Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Sohaib Nadeem <sohaib.nadeem@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>
---
drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
index 85e0d1c2a908..baecc0ffe758 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
@@ -2123,7 +2123,7 @@ static int build_synthetic_soc_states(struct clk_bw_params *bw_params,
unsigned int max_dcfclk_mhz = 0, max_dispclk_mhz = 0, max_dppclk_mhz = 0,
max_phyclk_mhz = 0, max_dtbclk_mhz = 0, max_fclk_mhz = 0, max_uclk_mhz = 0;

- unsigned int min_dcfclk_mhz = 199, min_fclk_mhz = 299;
+ unsigned int min_dcfclk_mhz = 399, min_fclk_mhz = 599;

static const unsigned int num_dcfclk_stas = 5;
unsigned int dcfclk_sta_targets[DC__VOLTAGE_STATES] = {199, 615, 906, 1324, 1564};
--
2.43.0