From be7001b595ab5fae4c95bfe651d2388c2cb40b42 Mon Sep 17 00:00:00 2001
From: Yu-ting Shen <Yu-ting.Shen@amd.com>
Date: Fri, 7 Feb 2020 15:19:31 +0800
Subject: drm/amd/display: limit display clock to 100MHz to avoid FIFO error
Git-commit: cab5dec425f19f3d4eeca0d8e073578cbed66d8d
Patch-mainline: v5.7-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
[Why]
when changing display clock, SMU need to use power up DFS and use
DENTIST to ramp DFS DID to switch target frequency before switching back
to bypass.
[How]
fixed the minimum display clock to 100MHz, it's W/A the same with PCO.
Signed-off-by: Yu-ting Shen <Yu-ting.Shen@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c | 3 +++
drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c | 1 +
2 files changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
index 784ce535e1e5..e91bd2a0f6ec 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -2897,6 +2897,9 @@ void dcn20_calculate_dlg_params(
!= dm_dram_clock_change_unsupported;
context->bw_ctx.bw.dcn.clk.dppclk_khz = 0;
+ if (context->bw_ctx.bw.dcn.clk.dispclk_khz < dc->debug.min_disp_clk_khz)
+ context->bw_ctx.bw.dcn.clk.dispclk_khz = dc->debug.min_disp_clk_khz;
+
/*
* An artifact of dml pipe split/odm is that pipes get merged back together for
* calculation. Therefore we need to only extract for first pipe in ascending index order
diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
index aa73025c1747..dce4966eca20 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
@@ -859,6 +859,7 @@ static const struct dc_debug_options debug_defaults_drv = {
.timing_trace = false,
.clock_trace = true,
.disable_pplib_clock_request = true,
+ .min_disp_clk_khz = 100000,
.pipe_split_policy = MPC_SPLIT_AVOID_MULT_DISP,
.force_single_disp_pipe_split = false,
.disable_dcc = DCC_ENABLE,
--
2.28.0