FAILED: patch "[PATCH] drm/amd/display: Fix MST BW calculation Regression" failed to apply to 6.1-stable tree

gregkh
2024-08-19T10:22:04Z

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 338567d17627064dba63cf063459605e782f71d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024081953-undaunted-dining-ae84@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

338567d17627 ("drm/amd/display: Fix MST BW calculation Regression")
00c391102abc ("drm/amd/display: Add misc DC changes for DCN401")
da87132f641e ("drm/amd/display: Add some DCN401 reg name to macro definitions")
ef319dff5475 ("drm/amd/display: add support for chroma offset")
a41aa6a7d0a6 ("drm/amd/display: Add comments to improve the code readability")
5324e2b205a2 ("drm/amd/display: Add driver support for future FAMS versions")
f3736c0d979a ("drm/amd/display: Add code comments clock and encode code")
8b2cb32cf0c6 ("drm/amd/display: FEC overhead should be checked once for mst slot nums")
4df96ba66760 ("drm/amd/display: Add timing pixel encoding for mst mode validation")
2dbe9c2b2685 ("drm/amd/display: add DCN 351 version for microcode load")
1c5c36530a57 ("drm/amd/display: Set DCN351 BB and IP the same as DCN35")
5034b935f62a ("drm/amd/display: Modify DHCUB waterwark structures and functions")
9d43241953f7 ("drm/amd/display: Refactor DML2 interfaces")
8cffa89bd5e2 ("drm/amd/display: Expand DML2 callbacks")
2d5bb791e24f ("drm/amd/display: Implement update_planes_and_stream_v3 sequence")
88867807564e ("drm/amd/display: Refactor DPP into a component directory")
eed4edda910f ("drm/amd/display: Support long vblank feature")
caef6c453cf2 ("drm/amd/display: Add DML2 folder to include path")
2d7f3d1a5866 ("drm/amd/display: Implement wait_for_odm_update_pending_complete")
4f5b8d78ca43 ("drm/amd/display: Init DPPCLK from SMU on dcn32")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 338567d17627064dba63cf063459605e782f71d2 Mon Sep 17 00:00:00 2001
From: Fangzhi Zuo <Jerry.Zuo@amd.com>
Date: Mon, 29 Jul 2024 10:23:03 -0400
Subject: [PATCH] drm/amd/display: Fix MST BW calculation Regression

[Why & How]
Revert commit 8b2cb32cf0c6
("drm/amd/display: FEC overhead should be checked once for mst slot nums")
Because causes bw calculation regression

Cc: mario.limonciello@amd.com
Cc: alexander.deucher@amd.com
Reported-by: jirislaby@kernel.org
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3495
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1228093
Reviewed-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 12dbb3ed212fc7655fce421542a5add637f8af7a)
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 915eb2c08ece..2e9f6da1acdc 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -804,12 +804,25 @@ struct dsc_mst_fairness_params {
};

#if defined(CONFIG_DRM_AMD_DC_FP)
-static int kbps_to_peak_pbn(int kbps)
+static uint16_t get_fec_overhead_multiplier(struct dc_link *dc_link)
+{
+ u8 link_coding_cap;
+ uint16_t fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B;
+
+ link_coding_cap = dc_link_dp_mst_decide_link_encoding_format(dc_link);
+ if (link_coding_cap == DP_128b_132b_ENCODING)
+ fec_overhead_multiplier_x1000 = PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B;
+
+ return fec_overhead_multiplier_x1000;
+}
+
+static int kbps_to_peak_pbn(int kbps, uint16_t fec_overhead_multiplier_x1000)
{
u64 peak_kbps = kbps;

peak_kbps *= 1006;
- peak_kbps = div_u64(peak_kbps, 1000);
+ peak_kbps *= fec_overhead_multiplier_x1000;
+ peak_kbps = div_u64(peak_kbps, 1000 * 1000);
return (int) DIV64_U64_ROUND_UP(peak_kbps * 64, (54 * 8 * 1000));
}

@@ -910,11 +923,12 @@ static int increase_dsc_bpp(struct drm_atomic_state *state,
int link_timeslots_used;
int fair_pbn_alloc;
int ret = 0;
+ uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);

for (i = 0; i < count; i++) {
if (vars[i + k].dsc_enabled) {
initial_slack[i] =
- kbps_to_peak_pbn(params[i].bw_range.max_kbps) - vars[i + k].pbn;
+ kbps_to_peak_pbn(params[i].bw_range.max_kbps, fec_overhead_multiplier_x1000) - vars[i + k].pbn;
bpp_increased[i] = false;
remaining_to_increase += 1;
} else {
@@ -1010,6 +1024,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
int next_index;
int remaining_to_try = 0;
int ret;
+ uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);

for (i = 0; i < count; i++) {
if (vars[i + k].dsc_enabled
@@ -1039,7 +1054,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
if (next_index == -1)
break;

- vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps);
+ vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
ret = drm_dp_atomic_find_time_slots(state,
params[next_index].port->mgr,
params[next_index].port,
@@ -1052,8 +1067,7 @@ static int try_disable_dsc(struct drm_atomic_state *state,
vars[next_index].dsc_enabled = false;
vars[next_index].bpp_x16 = 0;
} else {
- vars[next_index].pbn = kbps_to_peak_pbn(
- params[next_index].bw_range.max_kbps);
+ vars[next_index].pbn = kbps_to_peak_pbn(params[next_index].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
ret = drm_dp_atomic_find_time_slots(state,
params[next_index].port->mgr,
params[next_index].port,
@@ -1082,6 +1096,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
int count = 0;
int i, k, ret;
bool debugfs_overwrite = false;
+ uint16_t fec_overhead_multiplier_x1000 = get_fec_overhead_multiplier(dc_link);

memset(params, 0, sizeof(params));

@@ -1146,7 +1161,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
/* Try no compression */
for (i = 0; i < count; i++) {
vars[i + k].aconnector = params[i].aconnector;
- vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
+ vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
vars[i + k].dsc_enabled = false;
vars[i + k].bpp_x16 = 0;
ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr, params[i].port,
@@ -1165,7 +1180,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
/* Try max compression */
for (i = 0; i < count; i++) {
if (params[i].compression_possible && params[i].clock_force_enable != DSC_CLK_FORCE_DISABLE) {
- vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps);
+ vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.min_kbps, fec_overhead_multiplier_x1000);
vars[i + k].dsc_enabled = true;
vars[i + k].bpp_x16 = params[i].bw_range.min_target_bpp_x16;
ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr,
@@ -1173,7 +1188,7 @@ static int compute_mst_dsc_configs_for_link(struct drm_atomic_state *state,
if (ret < 0)
return ret;
} else {
- vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps);
+ vars[i + k].pbn = kbps_to_peak_pbn(params[i].bw_range.stream_kbps, fec_overhead_multiplier_x1000);
vars[i + k].dsc_enabled = false;
vars[i + k].bpp_x16 = 0;
ret = drm_dp_atomic_find_time_slots(state, params[i].port->mgr,
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
index fa84d34b7373..600d6e221011 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h
@@ -46,6 +46,9 @@
#define SYNAPTICS_CASCADED_HUB_ID 0x5A
#define IS_SYNAPTICS_CASCADED_PANAMERA(devName, data) ((IS_SYNAPTICS_PANAMERA(devName) && ((int)data[2] == SYNAPTICS_CASCADED_HUB_ID)) ? 1 : 0)

+#define PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B 1031
+#define PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B 1000
+
enum mst_msg_ready_type {
NONE_MSG_RDY_EVENT = 0,
DOWN_REP_MSG_RDY_EVENT = 1,