[PATCH v2 0/8] MDSS reg bus interconnect

[PATCH v2 0/8] MDSS reg bus interconnect

[Dmitry Baryshkov]

Per agreement with Konrad, picked up this patch series.

Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
another path that needs to be handled to ensure MDSS functions properly,
namely the "reg bus", a.k.a the CPU-MDSS interconnect.

Gating that path may have a variety of effects. from none to otherwise
inexplicable DSI timeouts.

This series tries to address the lack of that.

Changes since v1:
- Dropped the DPU part, the MDSS vote seems to be enough
- Reworked MDSS voting patch. Replaced static bw value with the
  per-platform confgurable values.
- Added sm8450 DT patch.

Dmitry Baryshkov (6):
  drm/msm/mdss: correct UBWC programming for SM8550
  drm/msm/mdss: switch mdss to use devm_of_icc_get()
  drm/msm/mdss: inline msm_mdss_icc_request_bw()
  drm/msm/mdss: populate missing data
  drm/msm/mdss: Handle the reg bus ICC path
  arm64: dts: qcom: sm8450: provide MDSS cfg interconnect

Konrad Dybcio (2):
  dt-bindings: display/msm: Add reg bus and rotator interconnects
  drm/msm/mdss: Rename path references to mdp_path

 .../bindings/display/msm/mdss-common.yaml     |   2 +
 arch/arm64/boot/dts/qcom/sm8450.dtsi          |   9 +-
 drivers/gpu/drm/msm/msm_mdss.c                | 138 +++++++++++++-----
 3 files changed, 108 insertions(+), 41 deletions(-)

-- 
2.40.1

[PATCH v2 1/8] dt-bindings: display/msm: Add reg bus and rotator interconnects

[Dmitry Baryshkov]

From: Konrad Dybcio <konrad.dybcio@linaro.org>

Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there are
other connection paths:
- a path that connects rotator block to the DDR.
- a path that needs to be handled to ensure MDSS register access
  functions properly, namely the "reg bus", a.k.a the CPU-MDSS CFG
  interconnect.

Describe these paths bindings to allow using them in device trees and in
the driver

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 Documentation/devicetree/bindings/display/msm/mdss-common.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/msm/mdss-common.yaml b/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
index ccd7d6417523..30a8aed4289a 100644
--- a/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
+++ b/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
@@ -66,12 +66,14 @@ properties:
     items:
       - description: Interconnect path from mdp0 (or a single mdp) port to the data bus
       - description: Interconnect path from mdp1 port to the data bus
+      - description: Interconnect path from CPU to the reg bus
 
   interconnect-names:
     minItems: 1
     items:
       - const: mdp0-mem
       - const: mdp1-mem
+      - const: cpu-cfg
 
   resets:
     items:
-- 
2.40.1

Re: [PATCH v2 1/8] dt-bindings: display/msm: Add reg bus and rotator interconnects

[Krzysztof Kozlowski]

On 12/07/2023 14:11, Dmitry Baryshkov wrote:
> From: Konrad Dybcio <konrad.dybcio@linaro.org>
> 
> Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there are
> other connection paths:
> - a path that connects rotator block to the DDR.
> - a path that needs to be handled to ensure MDSS register access
>   functions properly, namely the "reg bus", a.k.a the CPU-MDSS CFG
>   interconnect.
> 
> Describe these paths bindings to allow using them in device trees and in
> the driver
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>


Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

[PATCH v2 2/8] drm/msm/mdss: correct UBWC programming for SM8550

[Dmitry Baryshkov]

The SM8550 platform employs newer UBWC decoder, which requires slightly
different programming.

Fixes: a2f33995c19d ("drm/msm: mdss: add support for SM8550")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index 05648c910c68..798bd4f3b662 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -189,6 +189,7 @@ static int _msm_mdss_irq_domain_add(struct msm_mdss *msm_mdss)
 #define UBWC_2_0 0x20000000
 #define UBWC_3_0 0x30000000
 #define UBWC_4_0 0x40000000
+#define UBWC_4_3 0x40030000
 
 static void msm_mdss_setup_ubwc_dec_20(struct msm_mdss *msm_mdss)
 {
@@ -227,7 +228,10 @@ static void msm_mdss_setup_ubwc_dec_40(struct msm_mdss *msm_mdss)
 		writel_relaxed(1, msm_mdss->mmio + UBWC_CTRL_2);
 		writel_relaxed(0, msm_mdss->mmio + UBWC_PREDICTION_MODE);
 	} else {
-		writel_relaxed(2, msm_mdss->mmio + UBWC_CTRL_2);
+		if (data->ubwc_dec_version == UBWC_4_3)
+			writel_relaxed(3, msm_mdss->mmio + UBWC_CTRL_2);
+		else
+			writel_relaxed(2, msm_mdss->mmio + UBWC_CTRL_2);
 		writel_relaxed(1, msm_mdss->mmio + UBWC_PREDICTION_MODE);
 	}
 }
@@ -271,6 +275,7 @@ static int msm_mdss_enable(struct msm_mdss *msm_mdss)
 		msm_mdss_setup_ubwc_dec_30(msm_mdss);
 		break;
 	case UBWC_4_0:
+	case UBWC_4_3:
 		msm_mdss_setup_ubwc_dec_40(msm_mdss);
 		break;
 	default:
@@ -569,6 +574,16 @@ static const struct msm_mdss_data sm8250_data = {
 	.macrotile_mode = 1,
 };
 
+static const struct msm_mdss_data sm8550_data = {
+	.ubwc_version = UBWC_4_0,
+	.ubwc_dec_version = UBWC_4_3,
+	.ubwc_swizzle = 6,
+	.ubwc_static = 1,
+	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
+	.highest_bank_bit = 3,
+	.macrotile_mode = 1,
+};
+
 static const struct of_device_id mdss_dt_match[] = {
 	{ .compatible = "qcom,mdss" },
 	{ .compatible = "qcom,msm8998-mdss" },
@@ -585,7 +600,7 @@ static const struct of_device_id mdss_dt_match[] = {
 	{ .compatible = "qcom,sm8250-mdss", .data = &sm8250_data },
 	{ .compatible = "qcom,sm8350-mdss", .data = &sm8250_data },
 	{ .compatible = "qcom,sm8450-mdss", .data = &sm8250_data },
-	{ .compatible = "qcom,sm8550-mdss", .data = &sm8250_data },
+	{ .compatible = "qcom,sm8550-mdss", .data = &sm8550_data },
 	{}
 };
 MODULE_DEVICE_TABLE(of, mdss_dt_match);
-- 
2.40.1

Re: [PATCH v2 2/8] drm/msm/mdss: correct UBWC programming for SM8550

[Abhinav Kumar]

On 7/12/2023 5:11 AM, Dmitry Baryshkov wrote:
> The SM8550 platform employs newer UBWC decoder, which requires slightly
> different programming.
> 
> Fixes: a2f33995c19d ("drm/msm: mdss: add support for SM8550")
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

Do we also need another fixes tag

Fixes: d68db6069a8e ("drm/msm/mdss: convert UBWC setup to use match data")

Also, this was previously part of 
https://patchwork.freedesktop.org/series/118074/ .

In this one its after the bindings change.

For easier picking into -fixes, will you be moving this ahead of the 
bindings change and OR do you want to keep this part of the old series 
as it seems better suited there.

I think even if I pick this for -fixes, rest of this series can be 
rebased without issues. But let me know what you would prefer.

Re: [PATCH v2 2/8] drm/msm/mdss: correct UBWC programming for SM8550

[Dmitry Baryshkov]

On 13/07/2023 01:02, Abhinav Kumar wrote:
> 
> 
> On 7/12/2023 5:11 AM, Dmitry Baryshkov wrote:
>> The SM8550 platform employs newer UBWC decoder, which requires slightly
>> different programming.
>>
>> Fixes: a2f33995c19d ("drm/msm: mdss: add support for SM8550")
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> 
> Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> 
> Do we also need another fixes tag
> 
> Fixes: d68db6069a8e ("drm/msm/mdss: convert UBWC setup to use match data")

No. We do not need to fix the conversion. Only the sm8550 setup.

> 
> Also, this was previously part of 
> https://patchwork.freedesktop.org/series/118074/ .
> 
> In this one its after the bindings change.
> 
> For easier picking into -fixes, will you be moving this ahead of the 
> bindings change and OR do you want to keep this part of the old series 
> as it seems better suited there.
> 
> I think even if I pick this for -fixes, rest of this series can be 
> rebased without issues. But let me know what you would prefer.


I had rejects with the original series (and 0 reviews), so it was easier 
to push that as a part of this series too.

I'm fine with you pulling either of the patches into -fixes.

-- 
With best wishes
Dmitry

[PATCH v2 3/8] drm/msm/mdss: switch mdss to use devm_of_icc_get()

[Dmitry Baryshkov]

Stop using hand-written reset function for ICC release, use
devm_of_icc_get() instead.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index 798bd4f3b662..304a6509e1fb 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -58,14 +58,14 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 	struct icc_path *path0;
 	struct icc_path *path1;
 
-	path0 = of_icc_get(dev, "mdp0-mem");
+	path0 = devm_of_icc_get(dev, "mdp0-mem");
 	if (IS_ERR_OR_NULL(path0))
 		return PTR_ERR_OR_ZERO(path0);
 
 	msm_mdss->path[0] = path0;
 	msm_mdss->num_paths = 1;
 
-	path1 = of_icc_get(dev, "mdp1-mem");
+	path1 = devm_of_icc_get(dev, "mdp1-mem");
 	if (!IS_ERR_OR_NULL(path1)) {
 		msm_mdss->path[1] = path1;
 		msm_mdss->num_paths++;
@@ -74,15 +74,6 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 	return 0;
 }
 
-static void msm_mdss_put_icc_path(void *data)
-{
-	struct msm_mdss *msm_mdss = data;
-	int i;
-
-	for (i = 0; i < msm_mdss->num_paths; i++)
-		icc_put(msm_mdss->path[i]);
-}
-
 static void msm_mdss_icc_request_bw(struct msm_mdss *msm_mdss, unsigned long bw)
 {
 	int i;
@@ -389,9 +380,6 @@ static struct msm_mdss *msm_mdss_init(struct platform_device *pdev, bool is_mdp5
 	dev_dbg(&pdev->dev, "mapped mdss address space @%pK\n", msm_mdss->mmio);
 
 	ret = msm_mdss_parse_data_bus_icc_path(&pdev->dev, msm_mdss);
-	if (ret)
-		return ERR_PTR(ret);
-	ret = devm_add_action_or_reset(&pdev->dev, msm_mdss_put_icc_path, msm_mdss);
 	if (ret)
 		return ERR_PTR(ret);
 
-- 
2.40.1

[PATCH v2 4/8] drm/msm/mdss: Rename path references to mdp_path

[Dmitry Baryshkov]

From: Konrad Dybcio <konrad.dybcio@linaro.org>

The DPU1 driver needs to handle all MDPn<->DDR paths, as well as
CPU<->SLAVE_DISPLAY_CFG. The former ones share how their values are
calculated, but the latter one has static predefines spanning all SoCs.

In preparation for supporting the CPU<->SLAVE_DISPLAY_CFG path, rename
the path-related struct members to include "mdp_".

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index 304a6509e1fb..809c93b22c9c 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -48,8 +48,8 @@ struct msm_mdss {
 		struct irq_domain *domain;
 	} irq_controller;
 	const struct msm_mdss_data *mdss_data;
-	struct icc_path *path[2];
-	u32 num_paths;
+	struct icc_path *mdp_path[2];
+	u32 num_mdp_paths;
 };
 
 static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
@@ -62,13 +62,13 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 	if (IS_ERR_OR_NULL(path0))
 		return PTR_ERR_OR_ZERO(path0);
 
-	msm_mdss->path[0] = path0;
-	msm_mdss->num_paths = 1;
+	msm_mdss->mdp_path[0] = path0;
+	msm_mdss->num_mdp_paths = 1;
 
 	path1 = devm_of_icc_get(dev, "mdp1-mem");
 	if (!IS_ERR_OR_NULL(path1)) {
-		msm_mdss->path[1] = path1;
-		msm_mdss->num_paths++;
+		msm_mdss->mdp_path[1] = path1;
+		msm_mdss->num_mdp_paths++;
 	}
 
 	return 0;
@@ -78,8 +78,8 @@ static void msm_mdss_icc_request_bw(struct msm_mdss *msm_mdss, unsigned long bw)
 {
 	int i;
 
-	for (i = 0; i < msm_mdss->num_paths; i++)
-		icc_set_bw(msm_mdss->path[i], 0, Bps_to_icc(bw));
+	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
+		icc_set_bw(msm_mdss->mdp_path[i], 0, Bps_to_icc(bw));
 }
 
 static void msm_mdss_irq(struct irq_desc *desc)
-- 
2.40.1

[PATCH v2 5/8] drm/msm/mdss: inline msm_mdss_icc_request_bw()

[Dmitry Baryshkov]

There are just two places where we set the bandwidth: in the resume and
in the suspend paths. Drop the wrapping function
msm_mdss_icc_request_bw() and call icc_set_bw() directly.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index 809c93b22c9c..eed96976e260 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -74,14 +74,6 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 	return 0;
 }
 
-static void msm_mdss_icc_request_bw(struct msm_mdss *msm_mdss, unsigned long bw)
-{
-	int i;
-
-	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
-		icc_set_bw(msm_mdss->mdp_path[i], 0, Bps_to_icc(bw));
-}
-
 static void msm_mdss_irq(struct irq_desc *desc)
 {
 	struct msm_mdss *msm_mdss = irq_desc_get_handler_data(desc);
@@ -229,14 +221,15 @@ static void msm_mdss_setup_ubwc_dec_40(struct msm_mdss *msm_mdss)
 
 static int msm_mdss_enable(struct msm_mdss *msm_mdss)
 {
-	int ret;
+	int ret, i;
 
 	/*
 	 * Several components have AXI clocks that can only be turned on if
 	 * the interconnect is enabled (non-zero bandwidth). Let's make sure
 	 * that the interconnects are at least at a minimum amount.
 	 */
-	msm_mdss_icc_request_bw(msm_mdss, MIN_IB_BW);
+	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
+		icc_set_bw(msm_mdss->mdp_path[i], 0, Bps_to_icc(MIN_IB_BW));
 
 	ret = clk_bulk_prepare_enable(msm_mdss->num_clocks, msm_mdss->clocks);
 	if (ret) {
@@ -284,8 +277,12 @@ static int msm_mdss_enable(struct msm_mdss *msm_mdss)
 
 static int msm_mdss_disable(struct msm_mdss *msm_mdss)
 {
+	int i;
+
 	clk_bulk_disable_unprepare(msm_mdss->num_clocks, msm_mdss->clocks);
-	msm_mdss_icc_request_bw(msm_mdss, 0);
+
+	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
+		icc_set_bw(msm_mdss->mdp_path[i], 0, 0);
 
 	return 0;
 }
-- 
2.40.1

[PATCH v2 6/8] drm/msm/mdss: populate missing data

[Dmitry Baryshkov]

As we are going to use MDSS data for DPU programming, populate missing
MDSS data. The UBWC 1.0 and no UBWC cases do not require MDSS
programming, so skip them.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index eed96976e260..b7765e63d549 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -252,6 +252,10 @@ static int msm_mdss_enable(struct msm_mdss *msm_mdss)
 	 * UBWC_n and the rest of params comes from hw data.
 	 */
 	switch (msm_mdss->mdss_data->ubwc_dec_version) {
+	case 0: /* no UBWC */
+	case UBWC_1_0:
+		/* do nothing */
+		break;
 	case UBWC_2_0:
 		msm_mdss_setup_ubwc_dec_20(msm_mdss);
 		break;
@@ -491,10 +495,22 @@ static int mdss_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct msm_mdss_data msm8998_data = {
+	.ubwc_version = UBWC_1_0,
+	.ubwc_dec_version = UBWC_1_0,
+	.highest_bank_bit = 1,
+};
+
+static const struct msm_mdss_data qcm2290_data = {
+	/* no UBWC */
+	.highest_bank_bit = 0x2,
+};
+
 static const struct msm_mdss_data sc7180_data = {
 	.ubwc_version = UBWC_2_0,
 	.ubwc_dec_version = UBWC_2_0,
 	.ubwc_static = 0x1e,
+	.highest_bank_bit = 0x3,
 };
 
 static const struct msm_mdss_data sc7280_data = {
@@ -547,6 +563,7 @@ static const struct msm_mdss_data sm6115_data = {
 	.ubwc_dec_version = UBWC_2_0,
 	.ubwc_swizzle = 7,
 	.ubwc_static = 0x11f,
+	.highest_bank_bit = 0x1,
 };
 
 static const struct msm_mdss_data sm8250_data = {
@@ -571,8 +588,8 @@ static const struct msm_mdss_data sm8550_data = {
 
 static const struct of_device_id mdss_dt_match[] = {
 	{ .compatible = "qcom,mdss" },
-	{ .compatible = "qcom,msm8998-mdss" },
-	{ .compatible = "qcom,qcm2290-mdss" },
+	{ .compatible = "qcom,msm8998-mdss", .data = &msm8998_data },
+	{ .compatible = "qcom,qcm2290-mdss", .data = &qcm2290_data },
 	{ .compatible = "qcom,sdm845-mdss", .data = &sdm845_data },
 	{ .compatible = "qcom,sc7180-mdss", .data = &sc7180_data },
 	{ .compatible = "qcom,sc7280-mdss", .data = &sc7280_data },
-- 
2.40.1

[PATCH v2 7/8] drm/msm/mdss: Handle the reg bus ICC path

[Dmitry Baryshkov]

Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
another path that needs to be handled to ensure MDSS functions properly,
namely the "reg bus", a.k.a the CPU-MDSS interconnect.

Gating that path may have a variety of effects, from none to otherwise
inexplicable DSI timeouts.

Provide a way for MDSS driver to vote on this bus.

A note regarding vote values. Newer platforms have corresponding
bandwidth values in the vendor DT files. For the older platforms there
was a static vote in the mdss_mdp and rotator drivers. I choose to be
conservative here and choose this value as a default.

Co-developed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/msm/msm_mdss.c | 51 +++++++++++++++++++++++++++++++---
 1 file changed, 47 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
index b7765e63d549..ee31a9ab88d4 100644
--- a/drivers/gpu/drm/msm/msm_mdss.c
+++ b/drivers/gpu/drm/msm/msm_mdss.c
@@ -26,6 +26,8 @@
 
 #define MIN_IB_BW	400000000UL /* Min ib vote 400MB */
 
+#define DEFAULT_REG_BW	153600000UL /* Used in mdss fbdev driver */
+
 struct msm_mdss_data {
 	u32 ubwc_version;
 	/* can be read from register 0x58 */
@@ -34,6 +36,8 @@ struct msm_mdss_data {
 	u32 ubwc_static;
 	u32 highest_bank_bit;
 	u32 macrotile_mode;
+
+	unsigned long reg_bus_bw;
 };
 
 struct msm_mdss {
@@ -50,6 +54,7 @@ struct msm_mdss {
 	const struct msm_mdss_data *mdss_data;
 	struct icc_path *mdp_path[2];
 	u32 num_mdp_paths;
+	struct icc_path *reg_bus_path;
 };
 
 static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
@@ -57,6 +62,7 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 {
 	struct icc_path *path0;
 	struct icc_path *path1;
+	struct icc_path *reg_bus_path;
 
 	path0 = devm_of_icc_get(dev, "mdp0-mem");
 	if (IS_ERR_OR_NULL(path0))
@@ -71,6 +77,10 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
 		msm_mdss->num_mdp_paths++;
 	}
 
+	reg_bus_path = of_icc_get(dev, "cpu-cfg");
+	if (!IS_ERR_OR_NULL(reg_bus_path))
+		msm_mdss->reg_bus_path = reg_bus_path;
+
 	return 0;
 }
 
@@ -231,6 +241,13 @@ static int msm_mdss_enable(struct msm_mdss *msm_mdss)
 	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
 		icc_set_bw(msm_mdss->mdp_path[i], 0, Bps_to_icc(MIN_IB_BW));
 
+	if (msm_mdss->mdss_data && msm_mdss->mdss_data->reg_bus_bw)
+		icc_set_bw(msm_mdss->reg_bus_path, 0,
+			   Bps_to_icc(msm_mdss->mdss_data->reg_bus_bw));
+	else
+		icc_set_bw(msm_mdss->reg_bus_path, 0,
+			   Bps_to_icc(DEFAULT_REG_BW));
+
 	ret = clk_bulk_prepare_enable(msm_mdss->num_clocks, msm_mdss->clocks);
 	if (ret) {
 		dev_err(msm_mdss->dev, "clock enable failed, ret:%d\n", ret);
@@ -288,6 +305,9 @@ static int msm_mdss_disable(struct msm_mdss *msm_mdss)
 	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
 		icc_set_bw(msm_mdss->mdp_path[i], 0, 0);
 
+	if (msm_mdss->reg_bus_path)
+		icc_set_bw(msm_mdss->reg_bus_path, 0, 0);
+
 	return 0;
 }
 
@@ -374,6 +394,8 @@ static struct msm_mdss *msm_mdss_init(struct platform_device *pdev, bool is_mdp5
 	if (!msm_mdss)
 		return ERR_PTR(-ENOMEM);
 
+	msm_mdss->mdss_data = of_device_get_match_data(&pdev->dev);
+
 	msm_mdss->mmio = devm_platform_ioremap_resource_byname(pdev, is_mdp5 ? "mdss_phys" : "mdss");
 	if (IS_ERR(msm_mdss->mmio))
 		return ERR_CAST(msm_mdss->mmio);
@@ -464,8 +486,6 @@ static int mdss_probe(struct platform_device *pdev)
 	if (IS_ERR(mdss))
 		return PTR_ERR(mdss);
 
-	mdss->mdss_data = of_device_get_match_data(&pdev->dev);
-
 	platform_set_drvdata(pdev, mdss);
 
 	/*
@@ -499,11 +519,13 @@ static const struct msm_mdss_data msm8998_data = {
 	.ubwc_version = UBWC_1_0,
 	.ubwc_dec_version = UBWC_1_0,
 	.highest_bank_bit = 1,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data qcm2290_data = {
 	/* no UBWC */
 	.highest_bank_bit = 0x2,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sc7180_data = {
@@ -511,6 +533,7 @@ static const struct msm_mdss_data sc7180_data = {
 	.ubwc_dec_version = UBWC_2_0,
 	.ubwc_static = 0x1e,
 	.highest_bank_bit = 0x3,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sc7280_data = {
@@ -520,6 +543,7 @@ static const struct msm_mdss_data sc7280_data = {
 	.ubwc_static = 1,
 	.highest_bank_bit = 1,
 	.macrotile_mode = 1,
+	.reg_bus_bw = 74000 * 1000,
 };
 
 static const struct msm_mdss_data sc8180x_data = {
@@ -527,6 +551,7 @@ static const struct msm_mdss_data sc8180x_data = {
 	.ubwc_dec_version = UBWC_3_0,
 	.highest_bank_bit = 3,
 	.macrotile_mode = 1,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sc8280xp_data = {
@@ -536,12 +561,14 @@ static const struct msm_mdss_data sc8280xp_data = {
 	.ubwc_static = 1,
 	.highest_bank_bit = 2,
 	.macrotile_mode = 1,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sdm845_data = {
 	.ubwc_version = UBWC_2_0,
 	.ubwc_dec_version = UBWC_2_0,
 	.highest_bank_bit = 2,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sm6350_data = {
@@ -550,12 +577,14 @@ static const struct msm_mdss_data sm6350_data = {
 	.ubwc_swizzle = 6,
 	.ubwc_static = 0x1e,
 	.highest_bank_bit = 1,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sm8150_data = {
 	.ubwc_version = UBWC_3_0,
 	.ubwc_dec_version = UBWC_3_0,
 	.highest_bank_bit = 2,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sm6115_data = {
@@ -564,6 +593,7 @@ static const struct msm_mdss_data sm6115_data = {
 	.ubwc_swizzle = 7,
 	.ubwc_static = 0x11f,
 	.highest_bank_bit = 0x1,
+	.reg_bus_bw = 76800 * 1000,
 };
 
 static const struct msm_mdss_data sm8250_data = {
@@ -574,6 +604,18 @@ static const struct msm_mdss_data sm8250_data = {
 	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
 	.highest_bank_bit = 3,
 	.macrotile_mode = 1,
+	.reg_bus_bw = 76800 * 1000,
+};
+
+static const struct msm_mdss_data sm8350_data = {
+	.ubwc_version = UBWC_4_0,
+	.ubwc_dec_version = UBWC_4_0,
+	.ubwc_swizzle = 6,
+	.ubwc_static = 1,
+	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
+	.highest_bank_bit = 3,
+	.macrotile_mode = 1,
+	.reg_bus_bw = 74000 * 1000,
 };
 
 static const struct msm_mdss_data sm8550_data = {
@@ -584,6 +626,7 @@ static const struct msm_mdss_data sm8550_data = {
 	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
 	.highest_bank_bit = 3,
 	.macrotile_mode = 1,
+	.reg_bus_bw = 57000 * 1000,
 };
 
 static const struct of_device_id mdss_dt_match[] = {
@@ -600,8 +643,8 @@ static const struct of_device_id mdss_dt_match[] = {
 	{ .compatible = "qcom,sm6375-mdss", .data = &sm6350_data },
 	{ .compatible = "qcom,sm8150-mdss", .data = &sm8150_data },
 	{ .compatible = "qcom,sm8250-mdss", .data = &sm8250_data },
-	{ .compatible = "qcom,sm8350-mdss", .data = &sm8250_data },
-	{ .compatible = "qcom,sm8450-mdss", .data = &sm8250_data },
+	{ .compatible = "qcom,sm8350-mdss", .data = &sm8350_data },
+	{ .compatible = "qcom,sm8450-mdss", .data = &sm8350_data },
 	{ .compatible = "qcom,sm8550-mdss", .data = &sm8550_data },
 	{}
 };
-- 
2.40.1

Re: [PATCH v2 7/8] drm/msm/mdss: Handle the reg bus ICC path

[Konrad Dybcio]

On 12.07.2023 14:11, Dmitry Baryshkov wrote:
> Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
> another path that needs to be handled to ensure MDSS functions properly,
> namely the "reg bus", a.k.a the CPU-MDSS interconnect.
> 
> Gating that path may have a variety of effects, from none to otherwise
> inexplicable DSI timeouts.
> 
> Provide a way for MDSS driver to vote on this bus.
> 
> A note regarding vote values. Newer platforms have corresponding
> bandwidth values in the vendor DT files. For the older platforms there
> was a static vote in the mdss_mdp and rotator drivers. I choose to be
> conservative here and choose this value as a default.
> 
> Co-developed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
We can store data in icc units (without the *1000).

Konrad
>  drivers/gpu/drm/msm/msm_mdss.c | 51 +++++++++++++++++++++++++++++++---
>  1 file changed, 47 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c
> index b7765e63d549..ee31a9ab88d4 100644
> --- a/drivers/gpu/drm/msm/msm_mdss.c
> +++ b/drivers/gpu/drm/msm/msm_mdss.c
> @@ -26,6 +26,8 @@
>  
>  #define MIN_IB_BW	400000000UL /* Min ib vote 400MB */
>  
> +#define DEFAULT_REG_BW	153600000UL /* Used in mdss fbdev driver */
> +
>  struct msm_mdss_data {
>  	u32 ubwc_version;
>  	/* can be read from register 0x58 */
> @@ -34,6 +36,8 @@ struct msm_mdss_data {
>  	u32 ubwc_static;
>  	u32 highest_bank_bit;
>  	u32 macrotile_mode;
> +
> +	unsigned long reg_bus_bw;
>  };
>  
>  struct msm_mdss {
> @@ -50,6 +54,7 @@ struct msm_mdss {
>  	const struct msm_mdss_data *mdss_data;
>  	struct icc_path *mdp_path[2];
>  	u32 num_mdp_paths;
> +	struct icc_path *reg_bus_path;
>  };
>  
>  static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
> @@ -57,6 +62,7 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
>  {
>  	struct icc_path *path0;
>  	struct icc_path *path1;
> +	struct icc_path *reg_bus_path;
>  
>  	path0 = devm_of_icc_get(dev, "mdp0-mem");
>  	if (IS_ERR_OR_NULL(path0))
> @@ -71,6 +77,10 @@ static int msm_mdss_parse_data_bus_icc_path(struct device *dev,
>  		msm_mdss->num_mdp_paths++;
>  	}
>  
> +	reg_bus_path = of_icc_get(dev, "cpu-cfg");
> +	if (!IS_ERR_OR_NULL(reg_bus_path))
> +		msm_mdss->reg_bus_path = reg_bus_path;
> +
>  	return 0;
>  }
>  
> @@ -231,6 +241,13 @@ static int msm_mdss_enable(struct msm_mdss *msm_mdss)
>  	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
>  		icc_set_bw(msm_mdss->mdp_path[i], 0, Bps_to_icc(MIN_IB_BW));
>  
> +	if (msm_mdss->mdss_data && msm_mdss->mdss_data->reg_bus_bw)
> +		icc_set_bw(msm_mdss->reg_bus_path, 0,
> +			   Bps_to_icc(msm_mdss->mdss_data->reg_bus_bw));
> +	else
> +		icc_set_bw(msm_mdss->reg_bus_path, 0,
> +			   Bps_to_icc(DEFAULT_REG_BW));
> +
>  	ret = clk_bulk_prepare_enable(msm_mdss->num_clocks, msm_mdss->clocks);
>  	if (ret) {
>  		dev_err(msm_mdss->dev, "clock enable failed, ret:%d\n", ret);
> @@ -288,6 +305,9 @@ static int msm_mdss_disable(struct msm_mdss *msm_mdss)
>  	for (i = 0; i < msm_mdss->num_mdp_paths; i++)
>  		icc_set_bw(msm_mdss->mdp_path[i], 0, 0);
>  
> +	if (msm_mdss->reg_bus_path)
> +		icc_set_bw(msm_mdss->reg_bus_path, 0, 0);
> +
>  	return 0;
>  }
>  
> @@ -374,6 +394,8 @@ static struct msm_mdss *msm_mdss_init(struct platform_device *pdev, bool is_mdp5
>  	if (!msm_mdss)
>  		return ERR_PTR(-ENOMEM);
>  
> +	msm_mdss->mdss_data = of_device_get_match_data(&pdev->dev);
> +
>  	msm_mdss->mmio = devm_platform_ioremap_resource_byname(pdev, is_mdp5 ? "mdss_phys" : "mdss");
>  	if (IS_ERR(msm_mdss->mmio))
>  		return ERR_CAST(msm_mdss->mmio);
> @@ -464,8 +486,6 @@ static int mdss_probe(struct platform_device *pdev)
>  	if (IS_ERR(mdss))
>  		return PTR_ERR(mdss);
>  
> -	mdss->mdss_data = of_device_get_match_data(&pdev->dev);
> -
>  	platform_set_drvdata(pdev, mdss);
>  
>  	/*
> @@ -499,11 +519,13 @@ static const struct msm_mdss_data msm8998_data = {
>  	.ubwc_version = UBWC_1_0,
>  	.ubwc_dec_version = UBWC_1_0,
>  	.highest_bank_bit = 1,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data qcm2290_data = {
>  	/* no UBWC */
>  	.highest_bank_bit = 0x2,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sc7180_data = {
> @@ -511,6 +533,7 @@ static const struct msm_mdss_data sc7180_data = {
>  	.ubwc_dec_version = UBWC_2_0,
>  	.ubwc_static = 0x1e,
>  	.highest_bank_bit = 0x3,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sc7280_data = {
> @@ -520,6 +543,7 @@ static const struct msm_mdss_data sc7280_data = {
>  	.ubwc_static = 1,
>  	.highest_bank_bit = 1,
>  	.macrotile_mode = 1,
> +	.reg_bus_bw = 74000 * 1000,
>  };
>  
>  static const struct msm_mdss_data sc8180x_data = {
> @@ -527,6 +551,7 @@ static const struct msm_mdss_data sc8180x_data = {
>  	.ubwc_dec_version = UBWC_3_0,
>  	.highest_bank_bit = 3,
>  	.macrotile_mode = 1,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sc8280xp_data = {
> @@ -536,12 +561,14 @@ static const struct msm_mdss_data sc8280xp_data = {
>  	.ubwc_static = 1,
>  	.highest_bank_bit = 2,
>  	.macrotile_mode = 1,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sdm845_data = {
>  	.ubwc_version = UBWC_2_0,
>  	.ubwc_dec_version = UBWC_2_0,
>  	.highest_bank_bit = 2,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sm6350_data = {
> @@ -550,12 +577,14 @@ static const struct msm_mdss_data sm6350_data = {
>  	.ubwc_swizzle = 6,
>  	.ubwc_static = 0x1e,
>  	.highest_bank_bit = 1,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sm8150_data = {
>  	.ubwc_version = UBWC_3_0,
>  	.ubwc_dec_version = UBWC_3_0,
>  	.highest_bank_bit = 2,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sm6115_data = {
> @@ -564,6 +593,7 @@ static const struct msm_mdss_data sm6115_data = {
>  	.ubwc_swizzle = 7,
>  	.ubwc_static = 0x11f,
>  	.highest_bank_bit = 0x1,
> +	.reg_bus_bw = 76800 * 1000,
>  };
>  
>  static const struct msm_mdss_data sm8250_data = {
> @@ -574,6 +604,18 @@ static const struct msm_mdss_data sm8250_data = {
>  	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
>  	.highest_bank_bit = 3,
>  	.macrotile_mode = 1,
> +	.reg_bus_bw = 76800 * 1000,
> +};
> +
> +static const struct msm_mdss_data sm8350_data = {
> +	.ubwc_version = UBWC_4_0,
> +	.ubwc_dec_version = UBWC_4_0,
> +	.ubwc_swizzle = 6,
> +	.ubwc_static = 1,
> +	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
> +	.highest_bank_bit = 3,
> +	.macrotile_mode = 1,
> +	.reg_bus_bw = 74000 * 1000,
>  };
>  
>  static const struct msm_mdss_data sm8550_data = {
> @@ -584,6 +626,7 @@ static const struct msm_mdss_data sm8550_data = {
>  	/* TODO: highest_bank_bit = 2 for LP_DDR4 */
>  	.highest_bank_bit = 3,
>  	.macrotile_mode = 1,
> +	.reg_bus_bw = 57000 * 1000,
>  };
>  
>  static const struct of_device_id mdss_dt_match[] = {
> @@ -600,8 +643,8 @@ static const struct of_device_id mdss_dt_match[] = {
>  	{ .compatible = "qcom,sm6375-mdss", .data = &sm6350_data },
>  	{ .compatible = "qcom,sm8150-mdss", .data = &sm8150_data },
>  	{ .compatible = "qcom,sm8250-mdss", .data = &sm8250_data },
> -	{ .compatible = "qcom,sm8350-mdss", .data = &sm8250_data },
> -	{ .compatible = "qcom,sm8450-mdss", .data = &sm8250_data },
> +	{ .compatible = "qcom,sm8350-mdss", .data = &sm8350_data },
> +	{ .compatible = "qcom,sm8450-mdss", .data = &sm8350_data },
>  	{ .compatible = "qcom,sm8550-mdss", .data = &sm8550_data },
>  	{}
>  };

[PATCH v2 8/8] arm64: dts: qcom: sm8450: provide MDSS cfg interconnect

[Dmitry Baryshkov]

Add support for the MDSS cfg-cpu bus vote on the SM8450 platform.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 arch/arm64/boot/dts/qcom/sm8450.dtsi | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
index 595533aeafc4..0b01f3027ee3 100644
--- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
@@ -13,6 +13,7 @@
 #include <dt-bindings/mailbox/qcom-ipcc.h>
 #include <dt-bindings/phy/phy-qcom-qmp.h>
 #include <dt-bindings/power/qcom-rpmpd.h>
+#include <dt-bindings/interconnect/qcom,icc.h>
 #include <dt-bindings/interconnect/qcom,sm8450.h>
 #include <dt-bindings/soc/qcom,gpr.h>
 #include <dt-bindings/soc/qcom,rpmh-rsc.h>
@@ -2672,8 +2673,12 @@ mdss: display-subsystem@ae00000 {
 
 			/* same path used twice */
 			interconnects = <&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
-					<&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>;
-			interconnect-names = "mdp0-mem", "mdp1-mem";
+					<&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
+					<&gem_noc MASTER_APPSS_PROC QCOM_ICC_TAG_ACTIVE_ONLY
+					 &config_noc SLAVE_DISPLAY_CFG QCOM_ICC_TAG_ACTIVE_ONLY>;
+			interconnect-names = "mdp0-mem",
+					     "mdp1-mem",
+					     "cpu-cfg";
 
 			resets = <&dispcc DISP_CC_MDSS_CORE_BCR>;
 
-- 
2.40.1

Re: [PATCH v2 8/8] arm64: dts: qcom: sm8450: provide MDSS cfg interconnect

[Konrad Dybcio]

On 12.07.2023 14:11, Dmitry Baryshkov wrote:
> Add support for the MDSS cfg-cpu bus vote on the SM8450 platform.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> index 595533aeafc4..0b01f3027ee3 100644
> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> @@ -13,6 +13,7 @@
>  #include <dt-bindings/mailbox/qcom-ipcc.h>
>  #include <dt-bindings/phy/phy-qcom-qmp.h>
>  #include <dt-bindings/power/qcom-rpmpd.h>
> +#include <dt-bindings/interconnect/qcom,icc.h>
>  #include <dt-bindings/interconnect/qcom,sm8450.h>
>  #include <dt-bindings/soc/qcom,gpr.h>
>  #include <dt-bindings/soc/qcom,rpmh-rsc.h>
> @@ -2672,8 +2673,12 @@ mdss: display-subsystem@ae00000 {
>  
>  			/* same path used twice */
>  			interconnects = <&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
> -					<&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>;
> -			interconnect-names = "mdp0-mem", "mdp1-mem";
> +					<&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
> +					<&gem_noc MASTER_APPSS_PROC QCOM_ICC_TAG_ACTIVE_ONLY
> +					 &config_noc SLAVE_DISPLAY_CFG QCOM_ICC_TAG_ACTIVE_ONLY>;
Looking at icc_set_tag occurences in msm-5.10/techpack/display,
I *think* active-only is only possible for the data bus (MDP-EBI)

Moreover, I think Linux is supposed to cast MDSS votes through the
APPS RSC (so, nodes without _DISP [1][2]) and conversely, DISP_RSC is
supposed to active-only votes

Konrad

[1] not that it matters today because it's not implemented yet
[2] https://lore.kernel.org/linux-arm-msm/20230708-topic-rpmh_icc_rsc-v1-0-b223bd2ac8dd@linaro.org

> +			interconnect-names = "mdp0-mem",
> +					     "mdp1-mem",
> +					     "cpu-cfg";
>  
>  			resets = <&dispcc DISP_CC_MDSS_CORE_BCR>;
>  

Re: [PATCH v2 8/8] arm64: dts: qcom: sm8450: provide MDSS cfg interconnect

[Dmitry Baryshkov]

On Thu, 13 Jul 2023 at 11:41, Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>
> On 12.07.2023 14:11, Dmitry Baryshkov wrote:
> > Add support for the MDSS cfg-cpu bus vote on the SM8450 platform.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  arch/arm64/boot/dts/qcom/sm8450.dtsi | 9 +++++++--
> >  1 file changed, 7 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> > index 595533aeafc4..0b01f3027ee3 100644
> > --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> > @@ -13,6 +13,7 @@
> >  #include <dt-bindings/mailbox/qcom-ipcc.h>
> >  #include <dt-bindings/phy/phy-qcom-qmp.h>
> >  #include <dt-bindings/power/qcom-rpmpd.h>
> > +#include <dt-bindings/interconnect/qcom,icc.h>
> >  #include <dt-bindings/interconnect/qcom,sm8450.h>
> >  #include <dt-bindings/soc/qcom,gpr.h>
> >  #include <dt-bindings/soc/qcom,rpmh-rsc.h>
> > @@ -2672,8 +2673,12 @@ mdss: display-subsystem@ae00000 {
> >
> >                       /* same path used twice */
> >                       interconnects = <&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
> > -                                     <&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>;
> > -                     interconnect-names = "mdp0-mem", "mdp1-mem";
> > +                                     <&mmss_noc MASTER_MDP_DISP 0 &mc_virt SLAVE_EBI1_DISP 0>,
> > +                                     <&gem_noc MASTER_APPSS_PROC QCOM_ICC_TAG_ACTIVE_ONLY
> > +                                      &config_noc SLAVE_DISPLAY_CFG QCOM_ICC_TAG_ACTIVE_ONLY>;
> Looking at icc_set_tag occurences in msm-5.10/techpack/display,
> I *think* active-only is only possible for the data bus (MDP-EBI)

Here I followed the vendor mdss fbdev driver (mdss_mdp.c), which
explicitly states:

static struct msm_bus_scale_pdata mdp_reg_bus_scale_table = {
        .usecase = mdp_reg_bus_usecases,
        .num_usecases = ARRAY_SIZE(mdp_reg_bus_usecases),
        .name = "mdss_reg",
        .active_only = true,
};

>
> Moreover, I think Linux is supposed to cast MDSS votes through the
> APPS RSC (so, nodes without _DISP [1][2]) and conversely, DISP_RSC is
> supposed to active-only votes

We can change this once your DISP_RSC lands. Anyway, I think we will
have to add the LLCC-MEM vote at some point later.

>
> Konrad
>
> [1] not that it matters today because it's not implemented yet
> [2] https://lore.kernel.org/linux-arm-msm/20230708-topic-rpmh_icc_rsc-v1-0-b223bd2ac8dd@linaro.org
>
> > +                     interconnect-names = "mdp0-mem",
> > +                                          "mdp1-mem",
> > +                                          "cpu-cfg";
> >
> >                       resets = <&dispcc DISP_CC_MDSS_CORE_BCR>;
> >



-- 
With best wishes
Dmitry

Re: (subset) [PATCH v2 0/8] MDSS reg bus interconnect

[Bjorn Andersson]

On Wed, 12 Jul 2023 15:11:37 +0300, Dmitry Baryshkov wrote:
> Per agreement with Konrad, picked up this patch series.
> 
> Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
> another path that needs to be handled to ensure MDSS functions properly,
> namely the "reg bus", a.k.a the CPU-MDSS interconnect.
> 
> Gating that path may have a variety of effects. from none to otherwise
> inexplicable DSI timeouts.
> 
> [...]

Applied, thanks!

[8/8] arm64: dts: qcom: sm8450: provide MDSS cfg interconnect
      commit: 4e125191e6cb00d6c3f3a8e1b67fd242e639b3c3

Best regards,
-- 
Bjorn Andersson <andersson@kernel.org>

Re: (subset) [PATCH v2 0/8] MDSS reg bus interconnect

[Abhinav Kumar]

On Wed, 12 Jul 2023 15:11:37 +0300, Dmitry Baryshkov wrote:
> Per agreement with Konrad, picked up this patch series.
> 
> Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
> another path that needs to be handled to ensure MDSS functions properly,
> namely the "reg bus", a.k.a the CPU-MDSS interconnect.
> 
> Gating that path may have a variety of effects. from none to otherwise
> inexplicable DSI timeouts.
> 
> [...]

Applied, thanks!

[2/8] drm/msm/mdss: correct UBWC programming for SM8550
      https://gitlab.freedesktop.org/drm/msm/-/commit/a85c238c5ccd

Best regards,
-- 
Abhinav Kumar <quic_abhinavk@quicinc.com>