* [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
[not found] <20260615132834.2985346-1-can.guo@oss.qualcomm.com>
@ 2026-06-15 13:28 ` Can Guo
2026-06-16 3:54 ` Krzysztof Kozlowski
2026-06-16 10:36 ` Peter Wang (王信友)
2026-06-15 13:28 ` [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
1 sibling, 2 replies; 10+ messages in thread
From: Can Guo @ 2026-06-15 13:28 UTC (permalink / raw)
To: krzk, 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
UFS v5.0/UFSHCI v5.0 adds HS-G6 support (46.6 Gbps/lane) via UniPro
v3.0 and M-PHY v6.0. These specs define TX Equalization for all
High-Speed Gears (not only HS-G6) to compensate channel loss and
improve signal integrity at high speed.
For HS-G6, M-PHY uses PAM4 1b1b line coding. Pre-Coding may also be
required depending on channel characteristics.
Document vendor-neutral properties in ufs-common.yaml:
- txeq-preshoot-g[1-6]
- txeq-deemphasis-g[1-6]
- tx-precode-enable-g6
Values are per-lane Host/Device tuples (2 values for x1, 4 values for
x2). PreShoot/DeEmphasis range from 0..7, and Precode is 0/1.
These are board-specific signal-integrity tuning values. They depend on
channel SI/PHY characterization and validation (host PHY, device PHY,
package, and board routing), and are determined by HW/PHY designers.
Although UFSHCI v5.0 supports TX Equalization Training via UniPro v3.0,
which allows host software to determine optimal TX Equalization at
runtime, static board-specific TX Equalization settings in the Device
Tree are still necessary because:
- TX Equalization Training is not supported for HS-G3 and below
- TX Equalization Training is disabled on some platforms
Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
---
.../devicetree/bindings/ufs/ufs-common.yaml | 58 +++++++++++++++++++
1 file changed, 58 insertions(+)
diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
index ed97f5682509..cc32e1189d50 100644
--- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml
+++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml
@@ -105,6 +105,64 @@ properties:
Restricts the UFS controller to rate-a or rate-b for both TX and
RX directions.
+ tx-precode-enable-g6:
+ $ref: /schemas/types.yaml#/definitions/uint32-matrix
+ minItems: 1
+ items:
+ - items:
+ - description: Host_Lane0 precode
+ enum: [0, 1]
+ - description: Device_Lane0 precode
+ enum: [0, 1]
+ - items:
+ - description: Host_Lane1 precode
+ enum: [0, 1]
+ - description: Device_Lane1 precode
+ enum: [0, 1]
+ description:
+ Static TX Precode enable values for HS-G6 only.
+
+patternProperties:
+ "^txeq-preshoot-g[1-6]$":
+ $ref: /schemas/types.yaml#/definitions/uint32-matrix
+ minItems: 1
+ items:
+ - items:
+ - description: Host_Lane0 Preshoot value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - description: Device_Lane0 Preshoot value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - items:
+ - description: Host_Lane1 Preshoot value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - description: Device_Lane1 Preshoot value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ description: |
+ Static TX Equalization PreShoot settings for High Speed Gears. These
+ values are programmed to the corresponding UniPro PA layer attribute
+ PA_TxEQG[1-6]Setting. Each value selects a Pre-Shoot level as defined
+ by the MIPI M-PHY specification (TX_HS_PreShoot_Setting).
+
+ "^txeq-deemphasis-g[1-6]$":
+ $ref: /schemas/types.yaml#/definitions/uint32-matrix
+ minItems: 1
+ items:
+ - items:
+ - description: Host_Lane0 DeEmphasis value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - description: Device_Lane0 DeEmphasis value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - items:
+ - description: Host_Lane1 DeEmphasis value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ - description: Device_Lane1 DeEmphasis value
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+ description: |
+ Static TX Equalization DeEmphasis settings for High Speed Gears. These
+ values are programmed to the corresponding UniPro PA layer attribute
+ PA_TxEQG[1-6]Setting. Each value selects a De-Emphasis level as defined
+ by the MIPI M-PHY specification (TX_HS_DeEmphasis_Setting).
+
dependencies:
freq-table-hz: [ clocks ]
operating-points-v2: [ clocks, clock-names ]
--
2.34.1
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
[not found] <20260615132834.2985346-1-can.guo@oss.qualcomm.com>
2026-06-15 13:28 ` [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
@ 2026-06-15 13:28 ` Can Guo
2026-06-15 13:38 ` Bart Van Assche
2026-06-16 8:04 ` Peter Wang (王信友)
1 sibling, 2 replies; 10+ messages in thread
From: Can Guo @ 2026-06-15 13:28 UTC (permalink / raw)
To: krzk, 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
Parse board-specific static TX Equalization settings from Device Tree for
each HS gear and store them in hba->tx_eq_params.
Parse txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6] as per-lane tuples:
<Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
For HS-G6, parse optional tx-precode-enable-g6 using the same per-lane
Host/Device tuple format. If provided, it must contain values for all
active lanes, and each value must be 0 or 1.
Introduce from_dt in struct ufshcd_tx_eq_params to track whether TX EQ
values came from static Device Tree data.
When TX Equalization Training is used, static settings are not final:
- If valid settings are retrieved from qTxEQGnSettings/wTxEQGnSettingsExt,
those retrieved settings override static Device Tree settings.
- If retrieval is not available/valid, TX EQTR runs and trained settings
override static Device Tree settings.
No behavior changes for platforms that do not provide these properties.
Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
---
drivers/ufs/core/ufs-txeq.c | 15 ++-
drivers/ufs/host/ufshcd-pltfrm.c | 156 +++++++++++++++++++++++++++++++
include/ufs/ufshcd.h | 2 +
3 files changed, 172 insertions(+), 1 deletion(-)
diff --git a/drivers/ufs/core/ufs-txeq.c b/drivers/ufs/core/ufs-txeq.c
index 4b264adfdf49..63616f8c2f74 100644
--- a/drivers/ufs/core/ufs-txeq.c
+++ b/drivers/ufs/core/ufs-txeq.c
@@ -1297,7 +1297,13 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
}
params = &hba->tx_eq_params[gear - 1];
- if (!params->is_valid || force_tx_eqtr) {
+ /*
+ * TX EQTR must run for the following cases:
+ * 1. TX EQ settings are invalid.
+ * 2. TX EQ settings are from Device Tree.
+ * 3. TX EQTR procedure is forced.
+ */
+ if (!params->is_valid || params->from_dt || force_tx_eqtr) {
int ret;
ret = ufshcd_tx_eqtr(hba, params, pwr_mode);
@@ -1310,6 +1316,8 @@ int ufshcd_config_tx_eq_settings(struct ufs_hba *hba,
/* Mark TX Equalization settings as valid */
params->is_valid = true;
params->is_trained = true;
+ /* TX EQTR succeeds, clear from_dt flag */
+ params->from_dt = false;
params->is_applied = false;
}
@@ -1495,6 +1503,11 @@ static void ufshcd_extract_tx_eq_settings_attrs(struct ufs_hba *hba, u8 gear)
}
params->is_valid = true;
+ /*
+ * Optimal TX EQ settings are retrieved from UFS device attributes,
+ * clear from_dt flag to avoid TX EQTR procedure.
+ */
+ params->from_dt = 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..5cf934bf10d0 100644
--- a/drivers/ufs/host/ufshcd-pltfrm.c
+++ b/drivers/ufs/host/ufshcd-pltfrm.c
@@ -210,6 +210,160 @@ static void ufshcd_init_lanes_per_dir(struct ufs_hba *hba)
}
}
+static int ufshcd_parse_tx_precode_enable(struct ufs_hba *hba,
+ bool host_precode_en[UFS_MAX_LANES],
+ bool device_precode_en[UFS_MAX_LANES])
+{
+ const char *prop_name = "tx-precode-enable-g6";
+ u32 num_elems = 2 * hba->lanes_per_direction;
+ const u32 lpd = hba->lanes_per_direction;
+ u32 precode[UFS_MAX_LANES * 2];
+ struct device *dev = hba->dev;
+ struct property *prop;
+ int count, err, i;
+
+ prop = of_find_property(dev->of_node, prop_name, NULL);
+ if (!prop)
+ return 0;
+
+ count = of_property_count_u32_elems(dev->of_node, prop_name);
+ if (count < 0)
+ return count;
+
+ if (count != num_elems) {
+ dev_err(dev, "Property %s has invalid count (%d), expecting %u\n",
+ prop_name, count, num_elems);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32_array(dev->of_node, prop_name, precode, num_elems);
+ if (err) {
+ dev_err(dev, "Failed to read %s property, %d\n", prop_name, err);
+ return err;
+ }
+
+ for (i = 0; i < num_elems; i++) {
+ if (precode[i] > 1) {
+ dev_err(dev, "Invalid TX precode value (%u) in %s property\n",
+ precode[i], prop_name);
+ return -EINVAL;
+ }
+ }
+
+ for (i = 0; i < lpd; i++) {
+ host_precode_en[i] = precode[i * 2];
+ device_precode_en[i] = precode[i * 2 + 1];
+ }
+
+ return 0;
+}
+
+static int ufshcd_parse_tx_eq_value_array(struct ufs_hba *hba,
+ const char *prop_name,
+ const u32 max_value,
+ u32 values[UFS_MAX_LANES * 2])
+{
+ u32 num_elems = 2 * hba->lanes_per_direction;
+ struct device *dev = hba->dev;
+ int count, err, i;
+
+ count = of_property_count_u32_elems(dev->of_node, prop_name);
+ if (count < 0)
+ return count;
+
+ if (count != num_elems) {
+ dev_err(dev, "Property %s has invalid count (%d), expecting %u\n",
+ prop_name, count, num_elems);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32_array(dev->of_node, prop_name, values, num_elems);
+ if (err) {
+ dev_err(dev, "Failed to read %s property, %d\n", prop_name, err);
+ return err;
+ }
+
+ for (i = 0; i < num_elems; i++) {
+ if (values[i] >= max_value) {
+ dev_err(dev, "Invalid TX EQ value (%u) in %s property\n",
+ values[i], prop_name);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * ufshcd_parse_tx_eq_settings_for_gear - Parse static TX EQ DT settings for one gear
+ * @hba: per adapter instance
+ * @gear: target HS gear
+ *
+ * Reads the txeq-preshoot-gN, txeq-deemphasis-gN, and (for G6)
+ * tx-precode-enable-g6 device-tree properties.
+ * If all present values are valid, stores them as static TX Equalization
+ * settings for the given gear.
+ */
+static void ufshcd_parse_tx_eq_settings_for_gear(struct ufs_hba *hba, int gear)
+{
+ bool device_precode_en[UFS_MAX_LANES] = { false };
+ bool host_precode_en[UFS_MAX_LANES] = { false };
+ const u32 lpd = hba->lanes_per_direction;
+ struct ufshcd_tx_eq_params *params;
+ u32 deemphasis[UFS_MAX_LANES * 2];
+ u32 preshoot[UFS_MAX_LANES * 2];
+ char prop_name[MAX_PROP_SIZE];
+ int err, lane;
+
+ snprintf(prop_name, MAX_PROP_SIZE, "txeq-preshoot-g%d", gear);
+ err = ufshcd_parse_tx_eq_value_array(hba, prop_name, TX_HS_NUM_PRESHOOT, preshoot);
+ if (err)
+ return;
+
+ snprintf(prop_name, MAX_PROP_SIZE, "txeq-deemphasis-g%d", gear);
+ err = ufshcd_parse_tx_eq_value_array(hba, prop_name, TX_HS_NUM_DEEMPHASIS, deemphasis);
+ if (err)
+ return;
+
+ if (gear == UFS_HS_G6) {
+ err = ufshcd_parse_tx_precode_enable(hba, host_precode_en, device_precode_en);
+ if (err)
+ return;
+ }
+
+ params = &hba->tx_eq_params[gear - 1];
+ for (lane = 0; lane < lpd; lane++) {
+ params->host[lane].preshoot = preshoot[lane * 2];
+ params->host[lane].deemphasis = deemphasis[lane * 2];
+ params->host[lane].precode_en = host_precode_en[lane];
+
+ params->device[lane].preshoot = preshoot[lane * 2 + 1];
+ params->device[lane].deemphasis = deemphasis[lane * 2 + 1];
+ params->device[lane].precode_en = device_precode_en[lane];
+ }
+
+ params->is_valid = true;
+ params->from_dt = true;
+}
+
+static void ufshcd_parse_static_tx_eq_settings(struct ufs_hba *hba)
+{
+ const u32 lpd = hba->lanes_per_direction;
+ int gear;
+
+ if (!lpd)
+ return;
+
+ if (lpd > UFS_MAX_LANES) {
+ dev_warn(hba->dev, "lanes_per_direction (%u) exceeds UFS_MAX_LANES (%u)\n",
+ lpd, UFS_MAX_LANES);
+ return;
+ }
+
+ for (gear = UFS_HS_G1; gear <= UFS_HS_GEAR_MAX; gear++)
+ ufshcd_parse_tx_eq_settings_for_gear(hba, gear);
+}
+
/**
* ufshcd_parse_clock_min_max_freq - Parse MIN and MAX clocks freq
* @hba: per adapter instance
@@ -528,6 +682,8 @@ 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..0f87b081b2ff 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
+ * @from_dt: True if settings are from Device Tree
*/
struct ufshcd_tx_eq_params {
struct ufshcd_tx_eq_settings host[UFS_MAX_LANES];
@@ -367,6 +368,7 @@ struct ufshcd_tx_eq_params {
bool is_valid;
bool is_applied;
bool is_trained;
+ bool from_dt;
};
/**
--
2.34.1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-15 13:28 ` [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
@ 2026-06-15 13:38 ` Bart Van Assche
2026-06-16 8:05 ` Can Guo
2026-06-16 8:04 ` Peter Wang (王信友)
1 sibling, 1 reply; 10+ messages in thread
From: Bart Van Assche @ 2026-06-15 13:38 UTC (permalink / raw)
To: Can Guo, krzk, beanhuo, peter.wang, martin.petersen, mani
Cc: linux-scsi, Alim Akhtar, Avri Altman, James E.J. Bottomley,
Ram Kumar Dwivedi, Nitin Rawat, open list
On 6/15/26 6:28 AM, Can Guo wrote:
> + prop = of_find_property(dev->of_node, prop_name, NULL);
> + if (!prop)
> + return 0;
> +
> + count = of_property_count_u32_elems(dev->of_node, prop_name);
> + if (count < 0)
> + return count;
Can the above two of_*() calls be combined into a single of_*() call,
e.g. as follows?
count = of_property_count_u32_elems(dev->of_node, prop_name);
if (count == -EINVAL || count == -ENOENT)
return 0;
if (count < 0)
return count;
Thanks,
Bart.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
2026-06-15 13:28 ` [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
@ 2026-06-16 3:54 ` Krzysztof Kozlowski
2026-06-16 10:36 ` Peter Wang (王信友)
1 sibling, 0 replies; 10+ messages in thread
From: Krzysztof Kozlowski @ 2026-06-16 3:54 UTC (permalink / raw)
To: Can Guo, bvanassche, beanhuo, peter.wang, martin.petersen, mani
Cc: 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
On 15/06/2026 15:28, Can Guo wrote:
> UFS v5.0/UFSHCI v5.0 adds HS-G6 support (46.6 Gbps/lane) via UniPro
> v3.0 and M-PHY v6.0. These specs define TX Equalization for all
> High-Speed Gears (not only HS-G6) to compensate channel loss and
> improve signal integrity at high speed.
>
> For HS-G6, M-PHY uses PAM4 1b1b line coding. Pre-Coding may also be
> required depending on channel characteristics.
>
> Document vendor-neutral properties in ufs-common.yaml:
> - txeq-preshoot-g[1-6]
> - txeq-deemphasis-g[1-6]
> - tx-precode-enable-g6
>
> Values are per-lane Host/Device tuples (2 values for x1, 4 values for
> x2). PreShoot/DeEmphasis range from 0..7, and Precode is 0/1.
>
> These are board-specific signal-integrity tuning values. They depend on
> channel SI/PHY characterization and validation (host PHY, device PHY,
> package, and board routing), and are determined by HW/PHY designers.
>
> Although UFSHCI v5.0 supports TX Equalization Training via UniPro v3.0,
> which allows host software to determine optimal TX Equalization at
> runtime, static board-specific TX Equalization settings in the Device
> Tree are still necessary because:
> - TX Equalization Training is not supported for HS-G3 and below
> - TX Equalization Training is disabled on some platforms
>
> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
> ---
> .../devicetree/bindings/ufs/ufs-common.yaml | 58 +++++++++++++++++++
> 1 file changed, 58 insertions(+)
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Best regards,
Krzysztof
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-15 13:28 ` [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
2026-06-15 13:38 ` Bart Van Assche
@ 2026-06-16 8:04 ` Peter Wang (王信友)
2026-06-16 9:09 ` Can Guo
1 sibling, 1 reply; 10+ messages in thread
From: Peter Wang (王信友) @ 2026-06-16 8:04 UTC (permalink / raw)
To: beanhuo, mani, can.guo, bvanassche, krzk, martin.petersen
Cc: linux-scsi, quic_nitirawa, linux-kernel, alim.akhtar,
avri.altman, quic_rdwivedi, James.Bottomley
On Mon, 2026-06-15 at 06:28 -0700, Can Guo wrote:
> Parse board-specific static TX Equalization settings from Device Tree
> for
> each HS gear and store them in hba->tx_eq_params.
>
> Parse txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6] as per-lane
> tuples:
> <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
>
> For HS-G6, parse optional tx-precode-enable-g6 using the same per-
> lane
> Host/Device tuple format. If provided, it must contain values for all
> active lanes, and each value must be 0 or 1.
>
> Introduce from_dt in struct ufshcd_tx_eq_params to track whether TX
> EQ
> values came from static Device Tree data.
>
> When TX Equalization Training is used, static settings are not final:
> - If valid settings are retrieved from
> qTxEQGnSettings/wTxEQGnSettingsExt,
> those retrieved settings override static Device Tree settings.
> - If retrieval is not available/valid, TX EQTR runs and trained
> settings
> override static Device Tree settings.
>
> No behavior changes for platforms that do not provide these
> properties.
>
> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
> ---
Hi Can,
I agree with Bart's comment.
Regarding sashiko-bot's comment, will you have another patch to
fix this pre-existing issue?
I think force_tx_eqtr could potentially trigger this deadlock.
Thanks.
Peter
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-15 13:38 ` Bart Van Assche
@ 2026-06-16 8:05 ` Can Guo
0 siblings, 0 replies; 10+ messages in thread
From: Can Guo @ 2026-06-16 8:05 UTC (permalink / raw)
To: Bart Van Assche, krzk, beanhuo, peter.wang, martin.petersen, mani
Cc: linux-scsi, Alim Akhtar, Avri Altman, James E.J. Bottomley,
Ram Kumar Dwivedi, Nitin Rawat, open list
On 6/15/2026 9:38 PM, Bart Van Assche wrote:
> On 6/15/26 6:28 AM, Can Guo wrote:
>> + prop = of_find_property(dev->of_node, prop_name, NULL);
>> + if (!prop)
>> + return 0;
>> +
>> + count = of_property_count_u32_elems(dev->of_node, prop_name);
>> + if (count < 0)
>> + return count;
>
> Can the above two of_*() calls be combined into a single of_*() call,
> e.g. as follows?
>
> count = of_property_count_u32_elems(dev->of_node, prop_name);
> if (count == -EINVAL || count == -ENOENT)
> return 0;
> if (count < 0)
> return count;
Sure, will do.
Thanks,
Can Guo.
>
> Thanks,
>
> Bart.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-16 8:04 ` Peter Wang (王信友)
@ 2026-06-16 9:09 ` Can Guo
2026-06-16 10:35 ` Peter Wang (王信友)
0 siblings, 1 reply; 10+ messages in thread
From: Can Guo @ 2026-06-16 9:09 UTC (permalink / raw)
To: Peter Wang (王信友),
beanhuo, mani, bvanassche, krzk, martin.petersen
Cc: linux-scsi, quic_nitirawa, linux-kernel, alim.akhtar,
avri.altman, quic_rdwivedi, James.Bottomley
On 6/16/2026 4:04 PM, Peter Wang (王信友) wrote:
>
> On Mon, 2026-06-15 at 06:28 -0700, Can Guo wrote:
> > Parse board-specific static TX Equalization settings from Device Tree
> > for
> > each HS gear and store them in hba->tx_eq_params.
> >
> > Parse txeq-preshoot-g[1-6] and txeq-deemphasis-g[1-6] as per-lane
> > tuples:
> > <Host_Lane0 Device_Lane0>, [<Host_Lane1 Device_Lane1>].
> >
> > For HS-G6, parse optional tx-precode-enable-g6 using the same per-
> > lane
> > Host/Device tuple format. If provided, it must contain values for all
> > active lanes, and each value must be 0 or 1.
> >
> > Introduce from_dt in struct ufshcd_tx_eq_params to track whether TX
> > EQ
> > values came from static Device Tree data.
> >
> > When TX Equalization Training is used, static settings are not final:
> > - If valid settings are retrieved from
> > qTxEQGnSettings/wTxEQGnSettingsExt,
> > those retrieved settings override static Device Tree settings.
> > - If retrieval is not available/valid, TX EQTR runs and trained
> > settings
> > override static Device Tree settings.
> >
> > No behavior changes for platforms that do not provide these
> > properties.
> >
> > Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
> > ---
>
> Hi Can,
>
> I agree with Bart's comment.
> Regarding sashiko-bot's comment, will you have another patch to
> fix this pre-existing issue?
> I think force_tx_eqtr could potentially trigger this deadlock.
Yes, I pushed a separate fix to address the memory reclaim deadlock issue.
https://lore.kernel.org/all/20260616090654.421850-1-can.guo@oss.qualcomm.com/
Please help review.
Thanks,
Can Guo.
>
> Thanks.
> Peter
>
>
>
> ************* MEDIATEK Confidentiality Notice ********************
> The information contained in this e-mail message (including any
> attachments) may be confidential, proprietary, privileged, or otherwise
> exempt from disclosure under applicable laws. It is intended to be
> conveyed only to the designated recipient(s). Any use, dissemination,
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-16 9:09 ` Can Guo
@ 2026-06-16 10:35 ` Peter Wang (王信友)
2026-06-16 10:36 ` Can Guo
0 siblings, 1 reply; 10+ messages in thread
From: Peter Wang (王信友) @ 2026-06-16 10:35 UTC (permalink / raw)
To: beanhuo, mani, can.guo, bvanassche, krzk, martin.petersen
Cc: linux-scsi, quic_rdwivedi, James.Bottomley, linux-kernel,
alim.akhtar, quic_nitirawa, avri.altman
On Tue, 2026-06-16 at 17:09 +0800, Can Guo wrote:
> Yes, I pushed a separate fix to address the memory reclaim deadlock
> issue.
>
> https://lore.kernel.org/all/20260616090654.421850-1-can.guo@oss.qualcomm.com/
>
> Please help review.
>
> Thanks,
> Can Guo.
>
Understood. If you have made changes based on Bart's comment,
please feel free to add my review tag.
Thanks
Peter
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties
2026-06-15 13:28 ` [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
2026-06-16 3:54 ` Krzysztof Kozlowski
@ 2026-06-16 10:36 ` Peter Wang (王信友)
1 sibling, 0 replies; 10+ messages in thread
From: Peter Wang (王信友) @ 2026-06-16 10:36 UTC (permalink / raw)
To: beanhuo, mani, can.guo, bvanassche, krzk, martin.petersen
Cc: avri.altman, zhml, linux-scsi, robh, linux-kernel, krzk+dt,
alim.akhtar, quic_rdwivedi, conor+dt, devicetree
On Mon, 2026-06-15 at 06:28 -0700, Can Guo wrote:
> UFS v5.0/UFSHCI v5.0 adds HS-G6 support (46.6 Gbps/lane) via UniPro
> v3.0 and M-PHY v6.0. These specs define TX Equalization for all
> High-Speed Gears (not only HS-G6) to compensate channel loss and
> improve signal integrity at high speed.
>
> For HS-G6, M-PHY uses PAM4 1b1b line coding. Pre-Coding may also be
> required depending on channel characteristics.
>
> Document vendor-neutral properties in ufs-common.yaml:
> - txeq-preshoot-g[1-6]
> - txeq-deemphasis-g[1-6]
> - tx-precode-enable-g6
>
> Values are per-lane Host/Device tuples (2 values for x1, 4 values for
> x2). PreShoot/DeEmphasis range from 0..7, and Precode is 0/1.
>
> These are board-specific signal-integrity tuning values. They depend
> on
> channel SI/PHY characterization and validation (host PHY, device PHY,
> package, and board routing), and are determined by HW/PHY designers.
>
> Although UFSHCI v5.0 supports TX Equalization Training via UniPro
> v3.0,
> which allows host software to determine optimal TX Equalization at
> runtime, static board-specific TX Equalization settings in the Device
> Tree are still necessary because:
> - TX Equalization Training is not supported for HS-G3 and below
> - TX Equalization Training is disabled on some platforms
>
> Signed-off-by: Can Guo <can.guo@oss.qualcomm.com>
> ---
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings
2026-06-16 10:35 ` Peter Wang (王信友)
@ 2026-06-16 10:36 ` Can Guo
0 siblings, 0 replies; 10+ messages in thread
From: Can Guo @ 2026-06-16 10:36 UTC (permalink / raw)
To: Peter Wang (王信友),
beanhuo, mani, bvanassche, krzk, martin.petersen
Cc: linux-scsi, quic_rdwivedi, James.Bottomley, linux-kernel,
alim.akhtar, quic_nitirawa, avri.altman
On 6/16/2026 6:35 PM, Peter Wang (王信友) wrote:
>
> On Tue, 2026-06-16 at 17:09 +0800, Can Guo wrote:
> > Yes, I pushed a separate fix to address the memory reclaim deadlock
> > issue.
> >
> > https://lore.kernel.org/all/20260616090654.421850-1-can.guo@oss.qualcomm.com/
> >
> > Please help review.
> >
> > Thanks,
> > Can Guo.
> >
>
> Understood. If you have made changes based on Bart's comment,
> please feel free to add my review tag.
Sure, thanks.
Best Regards,
Can Guo.
>
> Thanks
> Peter
>
>
>
> ************* MEDIATEK Confidentiality Notice ********************
> The information contained in this e-mail message (including any
> attachments) may be confidential, proprietary, privileged, or otherwise
> exempt from disclosure under applicable laws. It is intended to be
> conveyed only to the designated recipient(s). Any use, dissemination,
> distribution, printing, retaining or copying of this e-mail (including its
> attachments) by unintended recipient(s) is strictly prohibited and may
> be unlawful. If you are not an intended recipient of this e-mail, or believe
> that you have received this e-mail in error, please notify the sender
> immediately (by replying to this e-mail), delete any and all copies of
> this e-mail (including any attachments) from your system, and do not
> disclose the content of this e-mail to any other person. Thank you!
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2026-06-16 10:36 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
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[not found] <20260615132834.2985346-1-can.guo@oss.qualcomm.com>
2026-06-15 13:28 ` [PATCH v9 1/2] dt-bindings: ufs: Document static TX Equalization settings properties Can Guo
2026-06-16 3:54 ` Krzysztof Kozlowski
2026-06-16 10:36 ` Peter Wang (王信友)
2026-06-15 13:28 ` [PATCH v9 2/2] scsi: ufs: core: Add support for static TX Equalization settings Can Guo
2026-06-15 13:38 ` Bart Van Assche
2026-06-16 8:05 ` Can Guo
2026-06-16 8:04 ` Peter Wang (王信友)
2026-06-16 9:09 ` Can Guo
2026-06-16 10:35 ` Peter Wang (王信友)
2026-06-16 10:36 ` Can Guo
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