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* [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
       [not found] <20260501134418.863432-1-can.guo@oss.qualcomm.com>
@ 2026-05-01 13:44 ` Can Guo
  2026-05-01 17:02   ` Conor Dooley
  2026-05-01 13:44 ` [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
  1 sibling, 1 reply; 9+ messages in thread
From: Can Guo @ 2026-05-01 13:44 UTC (permalink / raw)
  To: bvanassche, beanhuo, peter.wang, martin.petersen, mani
  Cc: linux-scsi, Can Guo, Alim Akhtar, Avri Altman, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Ram Kumar Dwivedi,
	Zhaoming Luo,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

HW design team usually provides static TX Equalization settings based on
PCB board characteristics. These settings can be passed from the device
tree to configure the TX Equalization parameters (PreShoot, DeEmphasis,
and PreCodeEn) for Host and Device across different HS gears.

Add patternProperties for txeq-settings-g[1-6] to support specifying
static TX Equalization settings.

Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
---
 Documentation/devicetree/bindings/ufs/ufs-common.yaml | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
index ed97f5682509..bc83948fc168 100644
--- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
+++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
@@ -105,6 +105,17 @@ properties:
       Restricts the UFS controller to rate-a or rate-b for both TX and
       RX directions.
 
+patternProperties:
+  "^txeq-settings-g[1-6]$":
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    minItems: 6
+    maxItems: 12
+    description: |
+      Static TX Equalization settings for High Speed (HS) gears.
+      The settings are specified as an array of tuples (PreShoot, DeEmphasis, PrecodeEn).
+      The array must contain these tuples in the following order:
+      Host Lane 0, [Host Lane 1], Device Lane 0, [Device Lane 1].
+
 dependencies:
   freq-table-hz: [ clocks ]
   operating-points-v2: [ clocks, clock-names ]
-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings
       [not found] <20260501134418.863432-1-can.guo@oss.qualcomm.com>
  2026-05-01 13:44 ` [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
@ 2026-05-01 13:44 ` Can Guo
  2026-05-14 13:57   ` Bean Huo
  1 sibling, 1 reply; 9+ messages in thread
From: Can Guo @ 2026-05-01 13:44 UTC (permalink / raw)
  To: bvanassche, beanhuo, peter.wang, martin.petersen, mani
  Cc: linux-scsi, Can Guo, Alim Akhtar, Avri Altman,
	James E.J. Bottomley, Ram Kumar Dwivedi, Nitin Rawat, open list

HW design team usually provide static TX Equalization settings based on
PCB board characteristics. The static TX Equalization settings may not be
optimal for all PCBs, but it is better than having nothing when adaptive
TX EQTR is not used. Since the static TX Equalization settings are PCB
board specific, pass the static TX Equalization settings from device tree.

Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
---
 drivers/ufs/core/ufs-txeq.c      |  4 +-
 drivers/ufs/host/ufshcd-pltfrm.c | 82 ++++++++++++++++++++++++++++++++
 include/ufs/ufshcd.h             |  5 ++
 3 files changed, 90 insertions(+), 1 deletion(-)

diff --git a/drivers/ufs/core/ufs-txeq.c b/drivers/ufs/core/ufs-txeq.c
index 4b264adfdf49..634ec039e129 100644
--- a/drivers/ufs/core/ufs-txeq.c
+++ b/drivers/ufs/core/ufs-txeq.c
@@ -1297,7 +1297,7 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
 	}
 
 	params = &hba->tx_eq_params[gear - 1];
-	if (!params->is_valid || force_tx_eqtr) {
+	if (!params->is_valid || params->is_static || force_tx_eqtr) {
 		int ret;
 
 		ret = ufshcd_tx_eqtr(hba, params, pwr_mode);
@@ -1310,6 +1310,7 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
 		/* Mark TX Equalization settings as valid */
 		params->is_valid = true;
 		params->is_trained = true;
+		params->is_static = false;
 		params->is_applied = false;
 	}
 
@@ -1495,6 +1496,7 @@ static void ufshcd_extract_tx_eq_settings_attrs(struct ufs_hba *hba, u8 gear)
 	}
 
 	params->is_valid = true;
+	params->is_static = false;
 }
 
 void ufshcd_retrieve_tx_eq_settings(struct ufs_hba *hba)
diff --git a/drivers/ufs/host/ufshcd-pltfrm.c b/drivers/ufs/host/ufshcd-pltfrm.c
index c2dafb583cf5..de6302e8c067 100644
--- a/drivers/ufs/host/ufshcd-pltfrm.c
+++ b/drivers/ufs/host/ufshcd-pltfrm.c
@@ -210,6 +210,86 @@ static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
 	}
 }
 
+static void ufshcd_parse_static_tx_eq_settings(struct ufs_hba *hba)
+{
+	size_t sz = hba->lanes_per_direction * 2 * TX_EQ_SETTINGS_TUPLE_SZ;
+	u32 settings[UFS_MAX_LANES * 2 * TX_EQ_SETTINGS_TUPLE_SZ];
+	u32 *host_settings, *device_settings;
+	u32 lpd = hba->lanes_per_direction;
+	struct ufshcd_tx_eq_params *params;
+	struct device *dev = hba->dev;
+	int i, err, count, gear, lane;
+	char prop_name[MAX_PROP_SIZE];
+
+	if (!lpd || lpd > UFS_MAX_LANES) {
+		dev_err(dev, "Invalid lanes-per-direction value (%u) provided\n", lpd);
+		return;
+	}
+
+	for (gear = UFS_HS_G1; gear <= UFS_HS_GEAR_MAX; gear++) {
+		snprintf(prop_name, MAX_PROP_SIZE, "txeq-settings-g%d", gear);
+		count = of_property_count_u32_elems(dev->of_node, prop_name);
+		if (count <= 0)
+			continue;
+
+		if (count != sz) {
+			dev_err(dev, "Property %s has invalid count (%d), expecting %zu \n",
+				prop_name, count, sz);
+			continue;
+		}
+
+		err = of_property_read_u32_array(dev->of_node, prop_name,
+						 settings, sz);
+		if (err) {
+			dev_err(dev, "Failed to read %s property, %d\n",
+				prop_name, err);
+			continue;
+		}
+
+		for (i = 0; i < count; i += TX_EQ_SETTINGS_TUPLE_SZ) {
+			if (settings[i] >= TX_HS_NUM_PRESHOOT) {
+				dev_err(dev, "An invalid TX EQ PreShoot (%d) provided in %s property\n",
+					settings[i], prop_name);
+				break;
+			}
+
+			if (settings[i + 1] >= TX_HS_NUM_DEEMPHASIS) {
+				dev_err(dev, "An invalid TX EQ DeEmphasis (%d) provided in %s property\n",
+					settings[i + 1], prop_name);
+				break;
+			}
+
+			if (settings[i + 2] > 1) {
+				dev_err(dev, "An invalid PrecodeEn (%d) provided in %s property\n",
+					settings[i + 2], prop_name);
+				break;
+			}
+		}
+
+		if (i != count)
+			continue;
+
+		params = &hba->tx_eq_params[gear - 1];
+		host_settings = settings;
+		device_settings = settings + lpd * TX_EQ_SETTINGS_TUPLE_SZ;
+
+		for (lane = 0; lane < lpd; lane++) {
+			params->host[lane].preshoot = host_settings[0];
+			params->host[lane].deemphasis =	host_settings[1];
+			params->host[lane].precode_en = host_settings[2];
+			host_settings += TX_EQ_SETTINGS_TUPLE_SZ;
+
+			params->device[lane].preshoot =	device_settings[0];
+			params->device[lane].deemphasis = device_settings[1];
+			params->device[lane].precode_en = device_settings[2];
+			device_settings += TX_EQ_SETTINGS_TUPLE_SZ;
+		}
+
+		params->is_valid = true;
+		params->is_static = true;
+	}
+}
+
 /**
  * ufshcd_parse_clock_min_max_freq  - Parse MIN and MAX clocks freq
  * @hba: per adapter instance
@@ -528,6 +608,8 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
 
 	ufshcd_init_lanes_per_dir(hba);
 
+	ufshcd_parse_static_tx_eq_settings(hba);
+
 	err = ufshcd_parse_operating_points(hba);
 	if (err) {
 		dev_err(dev, "%s: OPP parse failed %d\n", __func__, err);
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index f48d6416e299..2d385d42fcff 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -359,6 +359,7 @@ struct ufshcd_tx_eqtr_record {
  * @is_valid: True if parameter contains valid TX Equalization settings
  * @is_applied: True if settings have been applied to UniPro of both sides
  * @is_trained: True if parameters obtained from TX EQTR procedure
+ * @is_static: True if settings are static
  */
 struct ufshcd_tx_eq_params {
 	struct ufshcd_tx_eq_settings host[UFS_MAX_LANES];
@@ -367,8 +368,12 @@ struct ufshcd_tx_eq_params {
 	bool is_valid;
 	bool is_applied;
 	bool is_trained;
+	bool is_static;
 };
 
+/* TX EQ Settings Tuple has 3 elements - PreShoot, DeEmphasis and PrecodeEn. */
+#define TX_EQ_SETTINGS_TUPLE_SZ		3
+
 /**
  * struct ufs_hba_variant_ops - variant specific callbacks
  * @name: variant name
-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
  2026-05-01 13:44 ` [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
@ 2026-05-01 17:02   ` Conor Dooley
  2026-05-02  9:30     ` Can Guo
  0 siblings, 1 reply; 9+ messages in thread
From: Conor Dooley @ 2026-05-01 17:02 UTC (permalink / raw)
  To: Can Guo
  Cc: bvanassche, beanhuo, peter.wang, martin.petersen, mani,
	linux-scsi, Alim Akhtar, Avri Altman, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Ram Kumar Dwivedi,
	Zhaoming Luo,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

[-- Attachment #1: Type: text/plain, Size: 1950 bytes --]

On Fri, May 01, 2026 at 06:44:17AM -0700, Can Guo wrote:
> HW design team usually provides static TX Equalization settings based on
> PCB board characteristics. These settings can be passed from the device
> tree to configure the TX Equalization parameters (PreShoot, DeEmphasis,
> and PreCodeEn) for Host and Device across different HS gears.

I'm not familiar enough with ufs stuff to tell, but this commit message
sounds very qcom specific, but this is being added to a common file.
I'd like to see a lot more detail in the commit message, detailing why
this is truly applicable across IP vendors.

> 
> Add patternProperties for txeq-settings-g[1-6] to support specifying
> static TX Equalization settings.
> 
> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
> ---
>  Documentation/devicetree/bindings/ufs/ufs-common.yaml | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> index ed97f5682509..bc83948fc168 100644
> --- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> +++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> @@ -105,6 +105,17 @@ properties:
>        Restricts the UFS controller to rate-a or rate-b for both TX and
>        RX directions.
>  
> +patternProperties:
> +  "^txeq-settings-g[1-6]$":
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    minItems: 6
> +    maxItems: 12
> +    description: |
> +      Static TX Equalization settings for High Speed (HS) gears.
> +      The settings are specified as an array of tuples (PreShoot, DeEmphasis, PrecodeEn).
> +      The array must contain these tuples in the following order:
> +      Host Lane 0, [Host Lane 1], Device Lane 0, [Device Lane 1].
> +
>  dependencies:
>    freq-table-hz: [ clocks ]
>    operating-points-v2: [ clocks, clock-names ]
> -- 
> 2.34.1
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
  2026-05-01 17:02   ` Conor Dooley
@ 2026-05-02  9:30     ` Can Guo
  0 siblings, 0 replies; 9+ messages in thread
From: Can Guo @ 2026-05-02  9:30 UTC (permalink / raw)
  To: Conor Dooley
  Cc: bvanassche, beanhuo, peter.wang, martin.petersen, mani,
	linux-scsi, Alim Akhtar, Avri Altman, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Ram Kumar Dwivedi,
	Zhaoming Luo,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

Hi Conor,

On 5/2/2026 1:02 AM, Conor Dooley wrote:
> On Fri, May 01, 2026 at 06:44:17AM -0700, Can Guo wrote:
>> HW design team usually provides static TX Equalization settings based on
>> PCB board characteristics. These settings can be passed from the device
>> tree to configure the TX Equalization parameters (PreShoot, DeEmphasis,
>> and PreCodeEn) for Host and Device across different HS gears.
> I'm not familiar enough with ufs stuff to tell, but this commit message
> sounds very qcom specific, but this is being added to a common file.
> I'd like to see a lot more detail in the commit message, detailing why
> this is truly applicable across IP vendors.
Thanks for raising this point. I agree the current commit message is too 
narrow and I will
fix it in the next version.

This binding is intended to be vendor-neutral. The DT properties 
describe board-level
SI characterization data (per-gear/per-lane TX EQ values), not 
Qualcomm-specific controller
internals.

The tuple (PreShoot, DeEmphasis, PreCodeEn) is defined by the UFS link 
specs (MIPI UniPro
ver 3.0 & M-PHY ver 6.0), so the representation is generic and 
applicable to any UFS host
that supports TX EQ.

This is also consistent with existing kernel practice in PCIe, where 
board-provided Equalization
data is parsed from DT (see `of_pci_get_equalization_presets()` in 
`drivers/pci/of.c`).

I will update the commit message to explicitly describe this 
cross-vendor scope and to
clarify precedence: when adaptive TX EQ is enabled, DT static settings 
are fallback values
and can be overridden by retrieved/trained TX EQ settings.

Thanks,
Can Guo.
>
>> Add patternProperties for txeq-settings-g[1-6] to support specifying
>> static TX Equalization settings.
>>
>> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
>> ---
>>   Documentation/devicetree/bindings/ufs/ufs-common.yaml | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
>> index ed97f5682509..bc83948fc168 100644
>> --- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
>> +++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
>> @@ -105,6 +105,17 @@ properties:
>>         Restricts the UFS controller to rate-a or rate-b for both TX and
>>         RX directions.
>>   
>> +patternProperties:
>> +  "^txeq-settings-g[1-6]$":
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> +    minItems: 6
>> +    maxItems: 12
>> +    description: |
>> +      Static TX Equalization settings for High Speed (HS) gears.
>> +      The settings are specified as an array of tuples (PreShoot, DeEmphasis, PrecodeEn).
>> +      The array must contain these tuples in the following order:
>> +      Host Lane 0, [Host Lane 1], Device Lane 0, [Device Lane 1].
>> +
>>   dependencies:
>>     freq-table-hz: [ clocks ]
>>     operating-points-v2: [ clocks, clock-names ]
>> -- 
>> 2.34.1
>>


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings
  2026-05-01 13:44 ` [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
@ 2026-05-14 13:57   ` Bean Huo
  2026-05-15  8:12     ` Can Guo
  0 siblings, 1 reply; 9+ messages in thread
From: Bean Huo @ 2026-05-14 13:57 UTC (permalink / raw)
  To: Can Guo, bvanassche, beanhuo, peter.wang, martin.petersen, mani,
	powenkao
  Cc: linux-scsi, Alim Akhtar, Avri Altman, James E.J. Bottomley,
	Ram Kumar Dwivedi, Nitin Rawat, open list


Can, 


Sorry for the late review of this patch. I have several questions:


On Fri, 2026-05-01 at 06:44 -0700, Can Guo wrote:
> @@ -1297,7 +1297,7 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
>         }
>  
>         params = &hba->tx_eq_params[gear - 1];
> -       if (!params->is_valid || force_tx_eqtr) {
> +       if (!params->is_valid || params->is_static || force_tx_eqtr) {

When use_adaptive_txeq is on and params->is_static is true, EQTR will overwrite
the static values. That is reasonable since EQTR is more accurate. Is the
is_static check really needed here?

>                 int ret;
>  
> 

...

>  
>  void ufshcd_retrieve_tx_eq_settings(struct ufs_hba *hba)
> diff --git a/drivers/ufs/host/ufshcd-pltfrm.c b/drivers/ufs/host/ufshcd-
> pltfrm.c
> index c2dafb583cf5..de6302e8c067 100644
> --- a/drivers/ufs/host/ufshcd-pltfrm.c
> +++ b/drivers/ufs/host/ufshcd-pltfrm.c
> @@ -210,6 +210,86 @@ static void ufshcd_init_lanes_per_dir(struct ufs_hba
> *hba)
>         }
>  }
>  
> +static void ufshcd_parse_static_tx_eq_settings(struct ufs_hba *hba)
> +{
> +       size_t sz = hba->lanes_per_direction * 2 * TX_EQ_SETTINGS_TUPLE_SZ;
> +       u32 settings[UFS_MAX_LANES * 2 * TX_EQ_SETTINGS_TUPLE_SZ];
> +       u32 *host_settings, *device_settings;
> +       u32 lpd = hba->lanes_per_direction;
> +       struct ufshcd_tx_eq_params *params;
> 
....
> +
> +               params = &hba->tx_eq_params[gear - 1];
> +               host_settings = settings;
> +               device_settings = settings + lpd * TX_EQ_SETTINGS_TUPLE_SZ;
> +
> +               for (lane = 0; lane < lpd; lane++) {
> +                       params->host[lane].preshoot = host_settings[0];
> +                       params->host[lane].deemphasis = host_settings[1];
> +                       params->host[lane].precode_en = host_settings[2];
> +                       host_settings += TX_EQ_SETTINGS_TUPLE_SZ;
> +
> +                       params->device[lane].preshoot = device_settings[0];
> +                       params->device[lane].deemphasis = device_settings[1];
> +                       params->device[lane].precode_en = device_settings[2];
> +                       device_settings += TX_EQ_SETTINGS_TUPLE_SZ;
> +               }
> +
> +               params->is_valid = true;
> +               params->is_static = true;

I want to confirm I understand the code correctly. Please tell me if I am wrong:

1, When use_adaptive_txeq = 0: static values are used directly as TX EQ for HS-
G4 to G6. But ufshcd_config_tx_eq_settings() returns early when
use_adaptive_txeq = 0. So which function applies the static values in this
case? 

2, when use_adaptive_txeq = 1: static host values are used as the fixed host TX
EQ during EQTR. This is because ufs_qcom_get_rx_fom() only sweeps the device
side. It reads host values from hba->tx_eq_params[gear-1]->host[]. The static
values also work as the per-lane fallback in ufshcd_update_tx_eq_params() when
FOM is 0.

> +       }
> +}
> +
>  /**
>   * ufshcd_parse_clock_min_max_freq  - Parse MIN and MAX clocks freq
>   * @hba: per adapter instance
> @@ -528,6 +608,8 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
>  
>         ufshcd_init_lanes_per_dir(hba);
>  
> +       ufshcd_parse_static_tx_eq_settings(hba);
> +
>         err = ufshcd_parse_operating_points(hba);
>         if (err) {
>                 dev_err(dev, "%s: OPP parse failed %d\n", __func__, err);
> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
> index f48d6416e299..2d385d42fcff 100644
> --- a/include/ufs/ufshcd.h
> +++ b/include/ufs/ufshcd.h
> @@ -359,6 +359,7 @@ struct ufshcd_tx_eqtr_record {
>   * @is_valid: True if parameter contains valid TX Equalization settings
>   * @is_applied: True if settings have been applied to UniPro of both sides
>   * @is_trained: True if parameters obtained from TX EQTR procedure
> + * @is_static: True if settings are static
>   */
>  struct ufshcd_tx_eq_params {
>         struct ufshcd_tx_eq_settings host[UFS_MAX_LANES];
> @@ -367,8 +368,12 @@ struct ufshcd_tx_eq_params {
>         bool is_valid;
>         bool is_applied;
>         bool is_trained;
> +       bool is_static;

is_static is added next to is_trained, which was added in your "Add persistent
TX Equalization settings support" series, That series still has Brian's open
question about wTxEQGnSettingsExt Bit[15] being RFU per JESD220H:

https://patchwork.kernel.org/project/linux-scsi/cover/20260424151420.111675-1-can.guo@oss.qualcomm.co

Is this the reason why "Add persistent..." has not been merged?

I'd prefer to wait until that discussion concludes before tagging this one. I
hope this is ok for you.

Kind regards,
Bean



^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings
  2026-05-14 13:57   ` Bean Huo
@ 2026-05-15  8:12     ` Can Guo
  0 siblings, 0 replies; 9+ messages in thread
From: Can Guo @ 2026-05-15  8:12 UTC (permalink / raw)
  To: Bean Huo, bvanassche, beanhuo, peter.wang, martin.petersen, mani,
	powenkao
  Cc: linux-scsi, Alim Akhtar, Avri Altman, James E.J. Bottomley,
	Ram Kumar Dwivedi, Nitin Rawat, open list

Hi Bean,

On 5/14/2026 9:57 PM, Bean Huo wrote:
> Can,
>
>
> Sorry for the late review of this patch. I have several questions:
Not at all sir.
>
>
> On Fri, 2026-05-01 at 06:44 -0700, Can Guo wrote:
>> @@ -1297,7 +1297,7 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
>>          }
>>   
>>          params = &hba->tx_eq_params[gear - 1];
>> -       if (!params->is_valid || force_tx_eqtr) {
>> +       if (!params->is_valid || params->is_static || force_tx_eqtr) {
> When use_adaptive_txeq is on and params->is_static is true, EQTR will overwrite
> the static values. That is reasonable since EQTR is more accurate. Is the
> is_static check really needed here?
The check of flag is_static is required because we need it to 
differentiate the static
(DTS) settings from the settings retrieved from persistent storage:

- If settings are retrieved from persistent storage, TX EQTR should be 
skipped.
- If settings are from DTS, TX EQTR should execute anyways to override 
static settings.
>
>>                  int ret;
>>   
>>
> ...
>
>>   
>>   void ufshcd_retrieve_tx_eq_settings(struct ufs_hba *hba)
>> diff --git a/drivers/ufs/host/ufshcd-pltfrm.c b/drivers/ufs/host/ufshcd-
>> pltfrm.c
>> index c2dafb583cf5..de6302e8c067 100644
>> --- a/drivers/ufs/host/ufshcd-pltfrm.c
>> +++ b/drivers/ufs/host/ufshcd-pltfrm.c
>> @@ -210,6 +210,86 @@ static void ufshcd_init_lanes_per_dir(struct ufs_hba
>> *hba)
>>          }
>>   }
>>   
>> +static void ufshcd_parse_static_tx_eq_settings(struct ufs_hba *hba)
>> +{
>> +       size_t sz = hba->lanes_per_direction * 2 * TX_EQ_SETTINGS_TUPLE_SZ;
>> +       u32 settings[UFS_MAX_LANES * 2 * TX_EQ_SETTINGS_TUPLE_SZ];
>> +       u32 *host_settings, *device_settings;
>> +       u32 lpd = hba->lanes_per_direction;
>> +       struct ufshcd_tx_eq_params *params;
>>
> ....
>> +
>> +               params = &hba->tx_eq_params[gear - 1];
>> +               host_settings = settings;
>> +               device_settings = settings + lpd * TX_EQ_SETTINGS_TUPLE_SZ;
>> +
>> +               for (lane = 0; lane < lpd; lane++) {
>> +                       params->host[lane].preshoot = host_settings[0];
>> +                       params->host[lane].deemphasis = host_settings[1];
>> +                       params->host[lane].precode_en = host_settings[2];
>> +                       host_settings += TX_EQ_SETTINGS_TUPLE_SZ;
>> +
>> +                       params->device[lane].preshoot = device_settings[0];
>> +                       params->device[lane].deemphasis = device_settings[1];
>> +                       params->device[lane].precode_en = device_settings[2];
>> +                       device_settings += TX_EQ_SETTINGS_TUPLE_SZ;
>> +               }
>> +
>> +               params->is_valid = true;
>> +               params->is_static = true;
> I want to confirm I understand the code correctly. Please tell me if I am wrong:
>
> 1, When use_adaptive_txeq = 0: static values are used directly as TX EQ for HS-
> G4 to G6. But ufshcd_config_tx_eq_settings() returns early when
> use_adaptive_txeq = 0. So which function applies the static values in this
> case?
ufshcd_post_device_init()->
     ufshcd_tune_unipro_params()->
         ufshcd_apply_valid_tx_eq_settings()
>
> 2, when use_adaptive_txeq = 1: static host values are used as the fixed host TX
> EQ during EQTR. This is because ufs_qcom_get_rx_fom() only sweeps the device
> side. It reads host values from hba->tx_eq_params[gear-1]->host[]. The static
> values also work as the per-lane fallback in ufshcd_update_tx_eq_params() when
> FOM is 0.
Correct.
>
>> +       }
>> +}
>> +
>>   /**
>>    * ufshcd_parse_clock_min_max_freq  - Parse MIN and MAX clocks freq
>>    * @hba: per adapter instance
>> @@ -528,6 +608,8 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
>>   
>>          ufshcd_init_lanes_per_dir(hba);
>>   
>> +       ufshcd_parse_static_tx_eq_settings(hba);
>> +
>>          err = ufshcd_parse_operating_points(hba);
>>          if (err) {
>>                  dev_err(dev, "%s: OPP parse failed %d\n", __func__, err);
>> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
>> index f48d6416e299..2d385d42fcff 100644
>> --- a/include/ufs/ufshcd.h
>> +++ b/include/ufs/ufshcd.h
>> @@ -359,6 +359,7 @@ struct ufshcd_tx_eqtr_record {
>>    * @is_valid: True if parameter contains valid TX Equalization settings
>>    * @is_applied: True if settings have been applied to UniPro of both sides
>>    * @is_trained: True if parameters obtained from TX EQTR procedure
>> + * @is_static: True if settings are static
>>    */
>>   struct ufshcd_tx_eq_params {
>>          struct ufshcd_tx_eq_settings host[UFS_MAX_LANES];
>> @@ -367,8 +368,12 @@ struct ufshcd_tx_eq_params {
>>          bool is_valid;
>>          bool is_applied;
>>          bool is_trained;
>> +       bool is_static;
> is_static is added next to is_trained, which was added in your "Add persistent
> TX Equalization settings support" series, That series still has Brian's open
> question about wTxEQGnSettingsExt Bit[15] being RFU per JESD220H:
>
> https://patchwork.kernel.org/project/linux-scsi/cover/20260424151420.111675-1-can.guo@oss.qualcomm.co
>
> Is this the reason why "Add persistent..." has not been merged?
>
> I'd prefer to wait until that discussion concludes before tagging this one. I
> hope this is ok for you.
The persistent patch series has been merged by Martin, we just need to 
wait for Martin
to push the branch, then I will upload Patch V2 to address the comment 
from Conor.

Thanks,
Can Guo.
>
> Kind regards,
> Bean
>
>


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
  2026-05-27 14:40 ` [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
  2026-05-28  6:18   ` Manivannan Sadhasivam
@ 2026-05-30 11:36   ` Krzysztof Kozlowski
  1 sibling, 0 replies; 9+ messages in thread
From: Krzysztof Kozlowski @ 2026-05-30 11:36 UTC (permalink / raw)
  To: Can Guo
  Cc: bvanassche, beanhuo, peter.wang, martin.petersen, mani,
	linux-scsi, Alim Akhtar, Avri Altman, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Zhaoming Luo,
	Ram Kumar Dwivedi,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

On Wed, May 27, 2026 at 07:40:54AM -0700, Can Guo wrote:
> UFS v5.0/UFSHCI v5.0 add HS-G6 support (46.6 Gbps/lane) via UniPro v3.0
> and M-PHY v6.0. In these specs, TX Equalization is defined for all High
> Speed Gears (not only HS-G6) to compensate channel loss and improve signal
> integrity at high speed operation.
> 
> For HS-G6, M-PHY uses PAM4 1b1b line coding, Pre-Coding may also be
> required depending on channel characteristics.
> 
> Add vendor-neutral DT properties:
> 
> - patternProperties for txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6]
> - fixed property tx-precode-enable-g6
> 
> Each property is a uint32 array of per-lane tuples:
> <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>]
> 
> Accept 2 or 4 values (x1/x2 lane configs). PreShoot and DeEmphasis values
> are 0..7. Precode enable values are 0/1 and only applicable to HS-G6.
> 

Why are they SIX versions within three days? I see this for the third
time in Patchwork already.


Best regards,
Krzysztof


^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
  2026-05-27 14:40 ` [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
@ 2026-05-28  6:18   ` Manivannan Sadhasivam
  2026-05-30 11:36   ` Krzysztof Kozlowski
  1 sibling, 0 replies; 9+ messages in thread
From: Manivannan Sadhasivam @ 2026-05-28  6:18 UTC (permalink / raw)
  To: Can Guo
  Cc: bvanassche, beanhuo, peter.wang, martin.petersen, linux-scsi,
	Alim Akhtar, Avri Altman, Rob Herring, Krzysztof Kozlowski,
	Conor Dooley, Zhaoming Luo, Ram Kumar Dwivedi,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

On Wed, May 27, 2026 at 07:40:54AM -0700, Can Guo wrote:
> UFS v5.0/UFSHCI v5.0 add HS-G6 support (46.6 Gbps/lane) via UniPro v3.0
> and M-PHY v6.0. In these specs, TX Equalization is defined for all High
> Speed Gears (not only HS-G6) to compensate channel loss and improve signal
> integrity at high speed operation.
> 
> For HS-G6, M-PHY uses PAM4 1b1b line coding, Pre-Coding may also be
> required depending on channel characteristics.
> 
> Add vendor-neutral DT properties:
> 
> - patternProperties for txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6]
> - fixed property tx-precode-enable-g6
> 
> Each property is a uint32 array of per-lane tuples:
> <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>]
> 
> Accept 2 or 4 values (x1/x2 lane configs). PreShoot and DeEmphasis values
> are 0..7. Precode enable values are 0/1 and only applicable to HS-G6.
> 
> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>

Acked-by: Manivannan Sadhasivam <mani@kernel.org>

- Mani

> ---
>  .../devicetree/bindings/ufs/ufs-common.yaml   | 45 +++++++++++++++++++
>  1 file changed, 45 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> index ed97f5682509..d90cf25adfa5 100644
> --- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> +++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
> @@ -105,6 +105,51 @@ properties:
>        Restricts the UFS controller to rate-a or rate-b for both TX and
>        RX directions.
>  
> +  tx-precode-enable-g6:
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    oneOf:
> +      - minItems: 2
> +        maxItems: 2
> +      - minItems: 4
> +        maxItems: 4
> +    items:
> +      enum: [0, 1]
> +    description: |
> +      Static TX Precode enable values for HS-G6 only.
> +      Values are specified as per-lane tuples:
> +      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
> +
> +patternProperties:
> +  "^txeq-preshoot-g[1-6]$":
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    oneOf:
> +      - minItems: 2
> +        maxItems: 2
> +      - minItems: 4
> +        maxItems: 4
> +    items:
> +      minimum: 0
> +      maximum: 7
> +    description: |
> +      Static TX Equalization PreShoot values for High Speed Gears.
> +      Values are specified as per-lane tuples:
> +      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
> +
> +  "^txeq-deemphasis-g[1-6]$":
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    oneOf:
> +      - minItems: 2
> +        maxItems: 2
> +      - minItems: 4
> +        maxItems: 4
> +    items:
> +      minimum: 0
> +      maximum: 7
> +    description: |
> +      Static TX Equalization DeEmphasis values for High Speed Gears.
> +      Values are specified as per-lane tuples:
> +      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
> +
>  dependencies:
>    freq-table-hz: [ clocks ]
>    operating-points-v2: [ clocks, clock-names ]
> -- 
> 2.34.1

-- 
மணிவண்ணன் சதாசிவம்

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
       [not found] <20260527144055.2758170-1-can.guo@oss.qualcomm.com>
@ 2026-05-27 14:40 ` Can Guo
  2026-05-28  6:18   ` Manivannan Sadhasivam
  2026-05-30 11:36   ` Krzysztof Kozlowski
  0 siblings, 2 replies; 9+ messages in thread
From: Can Guo @ 2026-05-27 14:40 UTC (permalink / raw)
  To: bvanassche, beanhuo, peter.wang, martin.petersen, mani
  Cc: linux-scsi, Can Guo, Alim Akhtar, Avri Altman, Rob Herring,
	Krzysztof Kozlowski, Conor Dooley, Zhaoming Luo,
	Ram Kumar Dwivedi,
	open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	open list

UFS v5.0/UFSHCI v5.0 add HS-G6 support (46.6 Gbps/lane) via UniPro v3.0
and M-PHY v6.0. In these specs, TX Equalization is defined for all High
Speed Gears (not only HS-G6) to compensate channel loss and improve signal
integrity at high speed operation.

For HS-G6, M-PHY uses PAM4 1b1b line coding, Pre-Coding may also be
required depending on channel characteristics.

Add vendor-neutral DT properties:

- patternProperties for txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6]
- fixed property tx-precode-enable-g6

Each property is a uint32 array of per-lane tuples:
<Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>]

Accept 2 or 4 values (x1/x2 lane configs). PreShoot and DeEmphasis values
are 0..7. Precode enable values are 0/1 and only applicable to HS-G6.

Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
---
 .../devicetree/bindings/ufs/ufs-common.yaml   | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
index ed97f5682509..d90cf25adfa5 100644
--- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
+++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
@@ -105,6 +105,51 @@ properties:
       Restricts the UFS controller to rate-a or rate-b for both TX and
       RX directions.
 
+  tx-precode-enable-g6:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    oneOf:
+      - minItems: 2
+        maxItems: 2
+      - minItems: 4
+        maxItems: 4
+    items:
+      enum: [0, 1]
+    description: |
+      Static TX Precode enable values for HS-G6 only.
+      Values are specified as per-lane tuples:
+      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
+
+patternProperties:
+  "^txeq-preshoot-g[1-6]$":
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    oneOf:
+      - minItems: 2
+        maxItems: 2
+      - minItems: 4
+        maxItems: 4
+    items:
+      minimum: 0
+      maximum: 7
+    description: |
+      Static TX Equalization PreShoot values for High Speed Gears.
+      Values are specified as per-lane tuples:
+      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
+
+  "^txeq-deemphasis-g[1-6]$":
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    oneOf:
+      - minItems: 2
+        maxItems: 2
+      - minItems: 4
+        maxItems: 4
+    items:
+      minimum: 0
+      maximum: 7
+    description: |
+      Static TX Equalization DeEmphasis values for High Speed Gears.
+      Values are specified as per-lane tuples:
+      <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
+
 dependencies:
   freq-table-hz: [ clocks ]
   operating-points-v2: [ clocks, clock-names ]
-- 
2.34.1

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2026-05-30 11:36 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
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2026-05-01 13:44 ` [PATCH 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
2026-05-01 17:02   ` Conor Dooley
2026-05-02  9:30     ` Can Guo
2026-05-01 13:44 ` [PATCH 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
2026-05-14 13:57   ` Bean Huo
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