* FAILED: patch "[PATCH] drm/amd/display: Prevent Gating DTBCLK before It Is Properly" failed to apply to 6.12-stable tree
@ 2025-11-24 13:56 gregkh
2025-11-25 14:51 ` [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init Sasha Levin
0 siblings, 1 reply; 5+ messages in thread
From: gregkh @ 2025-11-24 13:56 UTC (permalink / raw)
To: Jerry.Zuo, alexander.deucher, aurabindo.pillai, charlene.liu,
daniel.wheeler, roman.li
Cc: stable
The patch below does not apply to the 6.12-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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x cfa0904a35fd0231f4d05da0190f0a22ed881cce
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025112425-aspirin-conduit-e44b@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From cfa0904a35fd0231f4d05da0190f0a22ed881cce Mon Sep 17 00:00:00 2001
From: Fangzhi Zuo <Jerry.Zuo@amd.com>
Date: Thu, 18 Sep 2025 16:25:45 -0400
Subject: [PATCH] drm/amd/display: Prevent Gating DTBCLK before It Is Properly
Latched
[why]
1. With allow_0_dtb_clk enabled, the time required to latch DTBCLK to 600 MHz
depends on the SMU. If DTBCLK is not latched to 600 MHz before set_mode completes,
gating DTBCLK causes the DP2 sink to lose its clock source.
2. The existing DTBCLK gating sequence ungates DTBCLK based on both pix_clk and ref_dtbclk,
but gates DTBCLK when either pix_clk or ref_dtbclk is zero.
pix_clk can be zero outside the set_mode sequence before DTBCLK is properly latched,
which can lead to DTBCLK being gated by mistake.
[how]
Consider both pixel_clk and ref_dtbclk when determining when it is safe to gate DTBCLK;
this is more accurate.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4701
Fixes: 5949e7c4890c ("drm/amd/display: Enable Dynamic DTBCLK Switch")
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit d04eb0c402780ca037b62a6aecf23b863545ebca)
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
index b11383fba35f..1eb04772f5da 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
@@ -394,6 +394,8 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
display_count = dcn35_get_active_display_cnt_wa(dc, context, &all_active_disps);
if (new_clocks->dtbclk_en && !new_clocks->ref_dtbclk_khz)
new_clocks->ref_dtbclk_khz = 600000;
+ else if (!new_clocks->dtbclk_en && new_clocks->ref_dtbclk_khz > 590000)
+ new_clocks->ref_dtbclk_khz = 0;
/*
* if it is safe to lower, but we are already in the lower state, we don't have to do anything
@@ -435,7 +437,7 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
actual_dtbclk = REG_READ(CLK1_CLK4_CURRENT_CNT);
- if (actual_dtbclk) {
+ if (actual_dtbclk > 590000) {
clk_mgr_base->clks.ref_dtbclk_khz = new_clocks->ref_dtbclk_khz;
clk_mgr_base->clks.dtbclk_en = new_clocks->dtbclk_en;
}
diff --git a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
index de6d62401362..c899c09ea31b 100644
--- a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
+++ b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
@@ -1411,7 +1411,7 @@ static void dccg35_set_dtbclk_dto(
__func__, params->otg_inst, params->pixclk_khz,
params->ref_dtbclk_khz, req_dtbclk_khz, phase, modulo);
- } else {
+ } else if (!params->ref_dtbclk_khz && !req_dtbclk_khz) {
switch (params->otg_inst) {
case 0:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL5, DTBCLK_P0_GATE_DISABLE, 0);
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init
2025-11-24 13:56 FAILED: patch "[PATCH] drm/amd/display: Prevent Gating DTBCLK before It Is Properly" failed to apply to 6.12-stable tree gregkh
@ 2025-11-25 14:51 ` Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 2/4] drm/amd/display: disable DPP RCG before DPP CLK enable Sasha Levin
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: Sasha Levin @ 2025-11-25 14:51 UTC (permalink / raw)
To: stable
Cc: Charlene Liu, Nicholas Kazlauskas, Martin Leung, Ausef Yousof,
Tom Chung, Daniel Wheeler, Alex Deucher, Sasha Levin
From: Charlene Liu <Charlene.Liu@amd.com>
[ Upstream commit 0ae47e971b9add8f7b8f8d55ac5f407f6f346758 ]
[why & how]
this is to init to HW real DTBCLK.
and use real HW DTBCLK status to update internal logic state
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Martin Leung <martin.leung@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Ausef Yousof <Ausef.Yousof@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>
Stable-dep-of: cfa0904a35fd ("drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
index a4ac601a30c35..3114b3fae9eff 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
@@ -393,6 +393,7 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
if (clk_mgr_base->clks.dtbclk_en && !new_clocks->dtbclk_en) {
if (clk_mgr->base.ctx->dc->config.allow_0_dtb_clk)
dcn35_smu_set_dtbclk(clk_mgr, false);
+
clk_mgr_base->clks.dtbclk_en = new_clocks->dtbclk_en;
}
/* check that we're not already in lower */
@@ -410,11 +411,17 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
}
if (!clk_mgr_base->clks.dtbclk_en && new_clocks->dtbclk_en) {
- dcn35_smu_set_dtbclk(clk_mgr, true);
- clk_mgr_base->clks.dtbclk_en = new_clocks->dtbclk_en;
+ int actual_dtbclk = 0;
dcn35_update_clocks_update_dtb_dto(clk_mgr, context, new_clocks->ref_dtbclk_khz);
- clk_mgr_base->clks.ref_dtbclk_khz = new_clocks->ref_dtbclk_khz;
+ dcn35_smu_set_dtbclk(clk_mgr, true);
+
+ actual_dtbclk = REG_READ(CLK1_CLK4_CURRENT_CNT);
+
+ if (actual_dtbclk) {
+ clk_mgr_base->clks.ref_dtbclk_khz = new_clocks->ref_dtbclk_khz;
+ clk_mgr_base->clks.dtbclk_en = new_clocks->dtbclk_en;
+ }
}
/* check that we're not already in D0 */
@@ -581,12 +588,10 @@ static bool dcn35_is_spll_ssc_enabled(struct clk_mgr *clk_mgr_base)
static void init_clk_states(struct clk_mgr *clk_mgr)
{
- struct clk_mgr_internal *clk_mgr_int = TO_CLK_MGR_INTERNAL(clk_mgr);
uint32_t ref_dtbclk = clk_mgr->clks.ref_dtbclk_khz;
+
memset(&(clk_mgr->clks), 0, sizeof(struct dc_clocks));
- if (clk_mgr_int->smu_ver >= SMU_VER_THRESHOLD)
- clk_mgr->clks.dtbclk_en = true; // request DTBCLK disable on first commit
clk_mgr->clks.ref_dtbclk_khz = ref_dtbclk; // restore ref_dtbclk
clk_mgr->clks.p_state_change_support = true;
clk_mgr->clks.prev_p_state_change_support = true;
@@ -597,6 +602,7 @@ static void init_clk_states(struct clk_mgr *clk_mgr)
void dcn35_init_clocks(struct clk_mgr *clk_mgr)
{
struct clk_mgr_internal *clk_mgr_int = TO_CLK_MGR_INTERNAL(clk_mgr);
+
init_clk_states(clk_mgr);
// to adjust dp_dto reference clock if ssc is enable otherwise to apply dprefclk
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 6.12.y 2/4] drm/amd/display: disable DPP RCG before DPP CLK enable
2025-11-25 14:51 ` [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init Sasha Levin
@ 2025-11-25 14:51 ` Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 3/4] drm/amd/display: Insert dccg log for easy debug Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 4/4] drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched Sasha Levin
2 siblings, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-11-25 14:51 UTC (permalink / raw)
To: stable
Cc: Charlene Liu, Hansen Dsouza, Ray Wu, Daniel Wheeler, Alex Deucher,
Sasha Levin
From: Charlene Liu <Charlene.Liu@amd.com>
[ Upstream commit 1bcd679209420305a86833bc357d50021909edaf ]
[why]
DPP CLK enable needs to disable DPPCLK RCG first.
The DPPCLK_en in dccg should always be enabled when the corresponding
pipe is enabled.
Reviewed-by: Hansen Dsouza <hansen.dsouza@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: cfa0904a35fd ("drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../amd/display/dc/dccg/dcn35/dcn35_dccg.c | 38 ++++++++++++-------
.../amd/display/dc/hwss/dcn35/dcn35_hwseq.c | 21 ++++++----
2 files changed, 38 insertions(+), 21 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
index b363f5360818d..ad910065f463f 100644
--- a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
+++ b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
@@ -391,6 +391,7 @@ static void dccg35_set_dppclk_rcg(struct dccg *dccg,
struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
+
if (!dccg->ctx->dc->debug.root_clock_optimization.bits.dpp && enable)
return;
@@ -411,6 +412,8 @@ static void dccg35_set_dppclk_rcg(struct dccg *dccg,
BREAK_TO_DEBUGGER();
break;
}
+ //DC_LOG_DEBUG("%s: inst(%d) DPPCLK rcg_disable: %d\n", __func__, inst, enable ? 0 : 1);
+
}
static void dccg35_set_dpstreamclk_rcg(
@@ -1112,30 +1115,24 @@ static void dcn35_set_dppclk_enable(struct dccg *dccg,
{
struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
+
switch (dpp_inst) {
case 0:
REG_UPDATE(DPPCLK_CTRL, DPPCLK0_EN, enable);
- if (dccg->ctx->dc->debug.root_clock_optimization.bits.dpp)
- REG_UPDATE(DCCG_GATE_DISABLE_CNTL6, DPPCLK0_ROOT_GATE_DISABLE, enable);
break;
case 1:
REG_UPDATE(DPPCLK_CTRL, DPPCLK1_EN, enable);
- if (dccg->ctx->dc->debug.root_clock_optimization.bits.dpp)
- REG_UPDATE(DCCG_GATE_DISABLE_CNTL6, DPPCLK1_ROOT_GATE_DISABLE, enable);
break;
case 2:
REG_UPDATE(DPPCLK_CTRL, DPPCLK2_EN, enable);
- if (dccg->ctx->dc->debug.root_clock_optimization.bits.dpp)
- REG_UPDATE(DCCG_GATE_DISABLE_CNTL6, DPPCLK2_ROOT_GATE_DISABLE, enable);
break;
case 3:
REG_UPDATE(DPPCLK_CTRL, DPPCLK3_EN, enable);
- if (dccg->ctx->dc->debug.root_clock_optimization.bits.dpp)
- REG_UPDATE(DCCG_GATE_DISABLE_CNTL6, DPPCLK3_ROOT_GATE_DISABLE, enable);
break;
default:
break;
}
+ //DC_LOG_DEBUG("%s: dpp_inst(%d) DPPCLK_EN = %d\n", __func__, dpp_inst, enable);
}
@@ -1163,14 +1160,18 @@ static void dccg35_update_dpp_dto(struct dccg *dccg, int dpp_inst,
ASSERT(false);
phase = 0xff;
}
+ dccg35_set_dppclk_rcg(dccg, dpp_inst, false);
REG_SET_2(DPPCLK_DTO_PARAM[dpp_inst], 0,
DPPCLK0_DTO_PHASE, phase,
DPPCLK0_DTO_MODULO, modulo);
dcn35_set_dppclk_enable(dccg, dpp_inst, true);
- } else
+ } else {
dcn35_set_dppclk_enable(dccg, dpp_inst, false);
+ /*we have this in hwss: disable_plane*/
+ //dccg35_set_dppclk_rcg(dccg, dpp_inst, true);
+ }
dccg->pipe_dppclk_khz[dpp_inst] = req_dppclk;
}
@@ -1182,6 +1183,7 @@ static void dccg35_set_dppclk_root_clock_gating(struct dccg *dccg,
if (!dccg->ctx->dc->debug.root_clock_optimization.bits.dpp)
return;
+
switch (dpp_inst) {
case 0:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL6, DPPCLK0_ROOT_GATE_DISABLE, enable);
@@ -1198,6 +1200,8 @@ static void dccg35_set_dppclk_root_clock_gating(struct dccg *dccg,
default:
break;
}
+ //DC_LOG_DEBUG("%s: dpp_inst(%d) rcg: %d\n", __func__, dpp_inst, enable);
+
}
static void dccg35_get_pixel_rate_div(
@@ -1521,28 +1525,30 @@ static void dccg35_set_physymclk_root_clock_gating(
switch (phy_inst) {
case 0:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL2,
- PHYASYMCLK_ROOT_GATE_DISABLE, enable ? 1 : 0);
+ PHYASYMCLK_ROOT_GATE_DISABLE, enable ? 0 : 1);
break;
case 1:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL2,
- PHYBSYMCLK_ROOT_GATE_DISABLE, enable ? 1 : 0);
+ PHYBSYMCLK_ROOT_GATE_DISABLE, enable ? 0 : 1);
break;
case 2:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL2,
- PHYCSYMCLK_ROOT_GATE_DISABLE, enable ? 1 : 0);
+ PHYCSYMCLK_ROOT_GATE_DISABLE, enable ? 0 : 1);
break;
case 3:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL2,
- PHYDSYMCLK_ROOT_GATE_DISABLE, enable ? 1 : 0);
+ PHYDSYMCLK_ROOT_GATE_DISABLE, enable ? 0 : 1);
break;
case 4:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL2,
- PHYESYMCLK_ROOT_GATE_DISABLE, enable ? 1 : 0);
+ PHYESYMCLK_ROOT_GATE_DISABLE, enable ? 0 : 1);
break;
default:
BREAK_TO_DEBUGGER();
return;
}
+ //DC_LOG_DEBUG("%s: dpp_inst(%d) PHYESYMCLK_ROOT_GATE_DISABLE:\n", __func__, phy_inst, enable ? 0 : 1);
+
}
static void dccg35_set_physymclk(
@@ -1643,6 +1649,8 @@ static void dccg35_dpp_root_clock_control(
return;
if (clock_on) {
+ dccg35_set_dppclk_rcg(dccg, dpp_inst, false);
+
/* turn off the DTO and leave phase/modulo at max */
dcn35_set_dppclk_enable(dccg, dpp_inst, 1);
REG_SET_2(DPPCLK_DTO_PARAM[dpp_inst], 0,
@@ -1654,6 +1662,8 @@ static void dccg35_dpp_root_clock_control(
REG_SET_2(DPPCLK_DTO_PARAM[dpp_inst], 0,
DPPCLK0_DTO_PHASE, 0,
DPPCLK0_DTO_MODULO, 1);
+ /*we have this in hwss: disable_plane*/
+ //dccg35_set_dppclk_rcg(dccg, dpp_inst, true);
}
dccg->dpp_clock_gated[dpp_inst] = !clock_on;
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
index 21aff7fa6375d..c739e5b2c5595 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_hwseq.c
@@ -241,11 +241,6 @@ void dcn35_init_hw(struct dc *dc)
dc->res_pool->hubbub->funcs->allow_self_refresh_control(dc->res_pool->hubbub,
!dc->res_pool->hubbub->ctx->dc->debug.disable_stutter);
}
- if (res_pool->dccg->funcs->dccg_root_gate_disable_control) {
- for (i = 0; i < res_pool->pipe_count; i++)
- res_pool->dccg->funcs->dccg_root_gate_disable_control(res_pool->dccg, i, 0);
- }
-
for (i = 0; i < res_pool->audio_count; i++) {
struct audio *audio = res_pool->audios[i];
@@ -885,12 +880,18 @@ void dcn35_init_pipes(struct dc *dc, struct dc_state *context)
void dcn35_enable_plane(struct dc *dc, struct pipe_ctx *pipe_ctx,
struct dc_state *context)
{
+ struct dpp *dpp = pipe_ctx->plane_res.dpp;
+ struct dccg *dccg = dc->res_pool->dccg;
+
+
/* enable DCFCLK current DCHUB */
pipe_ctx->plane_res.hubp->funcs->hubp_clk_cntl(pipe_ctx->plane_res.hubp, true);
/* initialize HUBP on power up */
pipe_ctx->plane_res.hubp->funcs->hubp_init(pipe_ctx->plane_res.hubp);
-
+ /*make sure DPPCLK is on*/
+ dccg->funcs->dccg_root_gate_disable_control(dccg, dpp->inst, true);
+ dpp->funcs->dpp_dppclk_control(dpp, false, true);
/* make sure OPP_PIPE_CLOCK_EN = 1 */
pipe_ctx->stream_res.opp->funcs->opp_pipe_clock_control(
pipe_ctx->stream_res.opp,
@@ -907,6 +908,7 @@ void dcn35_enable_plane(struct dc *dc, struct pipe_ctx *pipe_ctx,
// Program system aperture settings
pipe_ctx->plane_res.hubp->funcs->hubp_set_vm_system_aperture_settings(pipe_ctx->plane_res.hubp, &apt);
}
+ //DC_LOG_DEBUG("%s: dpp_inst(%d) =\n", __func__, dpp->inst);
if (!pipe_ctx->top_pipe
&& pipe_ctx->plane_state
@@ -922,6 +924,8 @@ void dcn35_plane_atomic_disable(struct dc *dc, struct pipe_ctx *pipe_ctx)
{
struct hubp *hubp = pipe_ctx->plane_res.hubp;
struct dpp *dpp = pipe_ctx->plane_res.dpp;
+ struct dccg *dccg = dc->res_pool->dccg;
+
dc->hwss.wait_for_mpcc_disconnect(dc, dc->res_pool, pipe_ctx);
@@ -939,7 +943,8 @@ void dcn35_plane_atomic_disable(struct dc *dc, struct pipe_ctx *pipe_ctx)
hubp->funcs->hubp_clk_cntl(hubp, false);
dpp->funcs->dpp_dppclk_control(dpp, false, false);
-/*to do, need to support both case*/
+ dccg->funcs->dccg_root_gate_disable_control(dccg, dpp->inst, false);
+
hubp->power_gated = true;
hubp->funcs->hubp_reset(hubp);
@@ -951,6 +956,8 @@ void dcn35_plane_atomic_disable(struct dc *dc, struct pipe_ctx *pipe_ctx)
pipe_ctx->top_pipe = NULL;
pipe_ctx->bottom_pipe = NULL;
pipe_ctx->plane_state = NULL;
+ //DC_LOG_DEBUG("%s: dpp_inst(%d)=\n", __func__, dpp->inst);
+
}
void dcn35_disable_plane(struct dc *dc, struct dc_state *state, struct pipe_ctx *pipe_ctx)
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 6.12.y 3/4] drm/amd/display: Insert dccg log for easy debug
2025-11-25 14:51 ` [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 2/4] drm/amd/display: disable DPP RCG before DPP CLK enable Sasha Levin
@ 2025-11-25 14:51 ` Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 4/4] drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched Sasha Levin
2 siblings, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-11-25 14:51 UTC (permalink / raw)
To: stable
Cc: Charlene Liu, Ovidiu (Ovi) Bunea, Yihan Zhu, Ivan Lipski,
Dan Wheeler, Alex Deucher, Sasha Levin
From: Charlene Liu <Charlene.Liu@amd.com>
[ Upstream commit 35bcc9168f3ce6416cbf3f776758be0937f84cb3 ]
[why]
Log for sequence tracking
Reviewed-by: Ovidiu (Ovi) Bunea <ovidiu.bunea@amd.com>
Reviewed-by: Yihan Zhu <yihan.zhu@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: cfa0904a35fd ("drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../amd/display/dc/dccg/dcn35/dcn35_dccg.c | 24 ++++++++++++++++---
1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
index ad910065f463f..a841eaafbaaa8 100644
--- a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
+++ b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
@@ -39,6 +39,7 @@
#define CTX \
dccg_dcn->base.ctx
+#include "logger_types.h"
#define DC_LOGGER \
dccg->ctx->logger
@@ -1132,7 +1133,7 @@ static void dcn35_set_dppclk_enable(struct dccg *dccg,
default:
break;
}
- //DC_LOG_DEBUG("%s: dpp_inst(%d) DPPCLK_EN = %d\n", __func__, dpp_inst, enable);
+ DC_LOG_DEBUG("%s: dpp_inst(%d) DPPCLK_EN = %d\n", __func__, dpp_inst, enable);
}
@@ -1400,6 +1401,10 @@ static void dccg35_set_dtbclk_dto(
* PIPEx_DTO_SRC_SEL should not be programmed during DTBCLK update since OTG may still be on, and the
* programming is handled in program_pix_clk() regardless, so it can be removed from here.
*/
+ DC_LOG_DEBUG("%s: OTG%d DTBCLK DTO enabled: pixclk_khz=%d, ref_dtbclk_khz=%d, req_dtbclk_khz=%d, phase=%d, modulo=%d\n",
+ __func__, params->otg_inst, params->pixclk_khz,
+ params->ref_dtbclk_khz, req_dtbclk_khz, phase, modulo);
+
} else {
switch (params->otg_inst) {
case 0:
@@ -1425,6 +1430,8 @@ static void dccg35_set_dtbclk_dto(
REG_WRITE(DTBCLK_DTO_MODULO[params->otg_inst], 0);
REG_WRITE(DTBCLK_DTO_PHASE[params->otg_inst], 0);
+
+ DC_LOG_DEBUG("%s: OTG%d DTBCLK DTO disabled\n", __func__, params->otg_inst);
}
}
@@ -1469,6 +1476,8 @@ static void dccg35_set_dpstreamclk(
BREAK_TO_DEBUGGER();
return;
}
+ DC_LOG_DEBUG("%s: dp_hpo_inst(%d) DPSTREAMCLK_EN = %d, DPSTREAMCLK_SRC_SEL = %d\n",
+ __func__, dp_hpo_inst, (src == REFCLK) ? 0 : 1, otg_inst);
}
@@ -1508,6 +1517,8 @@ static void dccg35_set_dpstreamclk_root_clock_gating(
BREAK_TO_DEBUGGER();
return;
}
+ DC_LOG_DEBUG("%s: dp_hpo_inst(%d) DPSTREAMCLK_ROOT_GATE_DISABLE = %d\n",
+ __func__, dp_hpo_inst, enable ? 1 : 0);
}
@@ -1547,7 +1558,7 @@ static void dccg35_set_physymclk_root_clock_gating(
BREAK_TO_DEBUGGER();
return;
}
- //DC_LOG_DEBUG("%s: dpp_inst(%d) PHYESYMCLK_ROOT_GATE_DISABLE:\n", __func__, phy_inst, enable ? 0 : 1);
+ DC_LOG_DEBUG("%s: dpp_inst(%d) PHYESYMCLK_ROOT_GATE_DISABLE: %d\n", __func__, phy_inst, enable ? 0 : 1);
}
@@ -1620,6 +1631,8 @@ static void dccg35_set_physymclk(
BREAK_TO_DEBUGGER();
return;
}
+ DC_LOG_DEBUG("%s: phy_inst(%d) PHYxSYMCLK_EN = %d, PHYxSYMCLK_SRC_SEL = %d\n",
+ __func__, phy_inst, force_enable ? 1 : 0, clk_src);
}
static void dccg35_set_valid_pixel_rate(
@@ -1667,6 +1680,7 @@ static void dccg35_dpp_root_clock_control(
}
dccg->dpp_clock_gated[dpp_inst] = !clock_on;
+ DC_LOG_DEBUG("%s: dpp_inst(%d) clock_on = %d\n", __func__, dpp_inst, clock_on);
}
static void dccg35_disable_symclk32_se(
@@ -1725,6 +1739,7 @@ static void dccg35_disable_symclk32_se(
BREAK_TO_DEBUGGER();
return;
}
+
}
static void dccg35_init_cb(struct dccg *dccg)
@@ -1732,7 +1747,6 @@ static void dccg35_init_cb(struct dccg *dccg)
(void)dccg;
/* Any RCG should be done when driver enter low power mode*/
}
-
void dccg35_init(struct dccg *dccg)
{
int otg_inst;
@@ -1747,6 +1761,8 @@ void dccg35_init(struct dccg *dccg)
for (otg_inst = 0; otg_inst < 2; otg_inst++) {
dccg31_disable_symclk32_le(dccg, otg_inst);
dccg31_set_symclk32_le_root_clock_gating(dccg, otg_inst, false);
+ DC_LOG_DEBUG("%s: OTG%d SYMCLK32_LE disabled and root clock gating disabled\n",
+ __func__, otg_inst);
}
// if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_se)
@@ -1759,6 +1775,8 @@ void dccg35_init(struct dccg *dccg)
dccg35_set_dpstreamclk(dccg, REFCLK, otg_inst,
otg_inst);
dccg35_set_dpstreamclk_root_clock_gating(dccg, otg_inst, false);
+ DC_LOG_DEBUG("%s: OTG%d DPSTREAMCLK disabled and root clock gating disabled\n",
+ __func__, otg_inst);
}
/*
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 6.12.y 4/4] drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched
2025-11-25 14:51 ` [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 2/4] drm/amd/display: disable DPP RCG before DPP CLK enable Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 3/4] drm/amd/display: Insert dccg log for easy debug Sasha Levin
@ 2025-11-25 14:51 ` Sasha Levin
2 siblings, 0 replies; 5+ messages in thread
From: Sasha Levin @ 2025-11-25 14:51 UTC (permalink / raw)
To: stable
Cc: Fangzhi Zuo, Charlene Liu, Aurabindo Pillai, Roman Li,
Dan Wheeler, Alex Deucher, Sasha Levin
From: Fangzhi Zuo <Jerry.Zuo@amd.com>
[ Upstream commit cfa0904a35fd0231f4d05da0190f0a22ed881cce ]
[why]
1. With allow_0_dtb_clk enabled, the time required to latch DTBCLK to 600 MHz
depends on the SMU. If DTBCLK is not latched to 600 MHz before set_mode completes,
gating DTBCLK causes the DP2 sink to lose its clock source.
2. The existing DTBCLK gating sequence ungates DTBCLK based on both pix_clk and ref_dtbclk,
but gates DTBCLK when either pix_clk or ref_dtbclk is zero.
pix_clk can be zero outside the set_mode sequence before DTBCLK is properly latched,
which can lead to DTBCLK being gated by mistake.
[how]
Consider both pixel_clk and ref_dtbclk when determining when it is safe to gate DTBCLK;
this is more accurate.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4701
Fixes: 5949e7c4890c ("drm/amd/display: Enable Dynamic DTBCLK Switch")
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit d04eb0c402780ca037b62a6aecf23b863545ebca)
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c | 4 +++-
drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
index 3114b3fae9eff..6e9d6090b10ff 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn35/dcn35_clk_mgr.c
@@ -377,6 +377,8 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
display_count = dcn35_get_active_display_cnt_wa(dc, context, &all_active_disps);
if (new_clocks->dtbclk_en && !new_clocks->ref_dtbclk_khz)
new_clocks->ref_dtbclk_khz = 600000;
+ else if (!new_clocks->dtbclk_en && new_clocks->ref_dtbclk_khz > 590000)
+ new_clocks->ref_dtbclk_khz = 0;
/*
* if it is safe to lower, but we are already in the lower state, we don't have to do anything
@@ -418,7 +420,7 @@ void dcn35_update_clocks(struct clk_mgr *clk_mgr_base,
actual_dtbclk = REG_READ(CLK1_CLK4_CURRENT_CNT);
- if (actual_dtbclk) {
+ if (actual_dtbclk > 590000) {
clk_mgr_base->clks.ref_dtbclk_khz = new_clocks->ref_dtbclk_khz;
clk_mgr_base->clks.dtbclk_en = new_clocks->dtbclk_en;
}
diff --git a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
index a841eaafbaaa8..57202ef3fd985 100644
--- a/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
+++ b/drivers/gpu/drm/amd/display/dc/dccg/dcn35/dcn35_dccg.c
@@ -1405,7 +1405,7 @@ static void dccg35_set_dtbclk_dto(
__func__, params->otg_inst, params->pixclk_khz,
params->ref_dtbclk_khz, req_dtbclk_khz, phase, modulo);
- } else {
+ } else if (!params->ref_dtbclk_khz && !req_dtbclk_khz) {
switch (params->otg_inst) {
case 0:
REG_UPDATE(DCCG_GATE_DISABLE_CNTL5, DTBCLK_P0_GATE_DISABLE, 0);
--
2.51.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2025-11-25 14:51 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-11-24 13:56 FAILED: patch "[PATCH] drm/amd/display: Prevent Gating DTBCLK before It Is Properly" failed to apply to 6.12-stable tree gregkh
2025-11-25 14:51 ` [PATCH 6.12.y 1/4] drm/amd/display: avoid reset DTBCLK at clock init Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 2/4] drm/amd/display: disable DPP RCG before DPP CLK enable Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 3/4] drm/amd/display: Insert dccg log for easy debug Sasha Levin
2025-11-25 14:51 ` [PATCH 6.12.y 4/4] drm/amd/display: Prevent Gating DTBCLK before It Is Properly Latched Sasha Levin
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