From b6cc2852813e9ac080946e16514d4878f248e410 Mon Sep 17 00:00:00 2001
From: Sung Lee <sung.lee@amd.com>
Date: Wed, 25 Mar 2020 14:44:25 -0400
Subject: drm/amd/display: Cap certain DML values for Low Pix Clk on DCN2.1
Git-commit: 06535a48e297f43ce5d188afde108fa768010b0c
Patch-mainline: v5.8-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
[WHY]
In certain conditions with low pixel clock, some values in DML may go
past the max due to margining for latency hiding. This causes assertions
to get hit.
[HOW]
If the pixel clock is low and some values are high, cap it to the max.
Signed-off-by: Sung Lee <sung.lee@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
.../display/dc/dml/dcn21/display_rq_dlg_calc_21.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_rq_dlg_calc_21.c b/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_rq_dlg_calc_21.c
index 3d445b135fe8..90a5fefef05b 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_rq_dlg_calc_21.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_rq_dlg_calc_21.c
@@ -1490,13 +1490,21 @@ static void dml_rq_dlg_get_dlg_params(
disp_dlg_regs->refcyc_per_pte_group_vblank_l =
(unsigned int) (dst_y_per_row_vblank * (double) htotal
* ref_freq_to_pix_freq / (double) dpte_groups_per_row_ub_l);
- ASSERT(disp_dlg_regs->refcyc_per_pte_group_vblank_l < (unsigned int)dml_pow(2, 13));
+ if ((refclk_freq_in_mhz / ref_freq_to_pix_freq < 28) &&
+ disp_dlg_regs->refcyc_per_pte_group_vblank_l >= (unsigned int)dml_pow(2, 13))
+ disp_dlg_regs->refcyc_per_pte_group_vblank_l = (1 << 13) - 1;
+ else
+ ASSERT(disp_dlg_regs->refcyc_per_pte_group_vblank_l < (unsigned int)dml_pow(2, 13));
if (dual_plane) {
disp_dlg_regs->refcyc_per_pte_group_vblank_c = (unsigned int) (dst_y_per_row_vblank
* (double) htotal * ref_freq_to_pix_freq
/ (double) dpte_groups_per_row_ub_c);
- ASSERT(disp_dlg_regs->refcyc_per_pte_group_vblank_c
+ if ((refclk_freq_in_mhz / ref_freq_to_pix_freq < 28) &&
+ disp_dlg_regs->refcyc_per_pte_group_vblank_c >= (unsigned int)dml_pow(2, 13))
+ disp_dlg_regs->refcyc_per_pte_group_vblank_c = (1 << 13) - 1;
+ else
+ ASSERT(disp_dlg_regs->refcyc_per_pte_group_vblank_c
< (unsigned int)dml_pow(2, 13));
}
--
2.28.0