Added support for overriding tuning parameters in QCOM SNPS PHY
from device tree. This parameter tuning is required to tune the
hs signal on dp/dm lines for electrical compliance to be successful.
Changes in v12:
Fixed nitpicks in driver code.
Changes in v11:
Made changes to logs added in phy driver.
Fixed nitpicks in code.
Changes in v10:
Fixed patch headers.
changes in v9:
Fixed nitpick in driver code.
changes in v8:
Fixed nitpick in driver code.
changes in v7:
Fixed nitpick in driver code and dtsi file.
changes in v6:
Fixed errors in dt-bindings.
Fixed nitpick in driver code.
changes in v5:
Fixed nitpicks in code.
Added minimum and maximum for each parameter added in dt-bindings.
Added proper suffixes to each parameter as per dtschema.
changes in v4:
Fixed nitpicks in code.
Initial compliance test results showed overshoot in the middle of eye
diagram. The current dt values were put in place to correct it and fix
overshoot issue.
changes in v3:
Added support for phy tuning parameters to be represented in bps and
corresponding register values to be written are obtained by traversing
through data map declared in the driver.
changes in v2:
Reading the individual fields in each overriding register from
device tree.
Krishna Kurapati (2):
phy: qcom-snps: Add support for overriding phy tuning parameters
arm64: dts: qcom: sc7280: Update SNPS Phy params for SC7280 IDP device
Sandeep Maheswaram (1):
dt-bindings: phy: qcom,usb-snps-femto-v2: Add phy override params
bindings
.../bindings/phy/qcom,usb-snps-femto-v2.yaml | 88 +++++++
arch/arm64/boot/dts/qcom/sc7280-idp.dtsi | 6 +
drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 252 ++++++++++++++++++++-
3 files changed, 344 insertions(+), 2 deletions(-)
--
2.7.4
From: Sandeep Maheswaram <[email protected]>
Add device tree bindings for SNPS phy tuning parameters.
Signed-off-by: Sandeep Maheswaram <[email protected]>
Signed-off-by: Krishna Kurapati <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
---
.../bindings/phy/qcom,usb-snps-femto-v2.yaml | 88 ++++++++++++++++++++++
1 file changed, 88 insertions(+)
diff --git a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
index f2aeffd..68e7096 100644
--- a/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
+++ b/Documentation/devicetree/bindings/phy/qcom,usb-snps-femto-v2.yaml
@@ -54,6 +54,94 @@ properties:
vdda33-supply:
description: phandle to the regulator 3.3V supply node.
+ qcom,hs-disconnect-bp:
+ description:
+ This adjusts the voltage level for the threshold used to
+ detect a disconnect event at the host.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -272
+ maximum: 2156
+
+ qcom,squelch-detector-bp:
+ description:
+ This adjusts the voltage level for the threshold used to
+ detect valid high-speed data.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -2090
+ maximum: 1590
+
+ qcom,hs-amplitude-bp:
+ description:
+ This adjusts the high-speed DC level voltage.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -660
+ maximum: 2670
+
+ qcom,pre-emphasis-duration-bp:
+ description:
+ This signal controls the duration for which the
+ HS pre-emphasis current is sourced onto DP<#> or DM<#>.
+ The HS Transmitter pre-emphasis duration is defined in terms of
+ unit amounts. One unit of pre-emphasis duration is approximately
+ 650 ps and is defined as 1X pre-emphasis duration.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: 10000
+ maximum: 20000
+
+ qcom,pre-emphasis-amplitude-bp:
+ description:
+ This signal controls the amount of current sourced to
+ DP<#> and DM<#> after a J-to-K or K-to-J transition.
+ The HS Transmitter pre-emphasis current is defined in terms of unit
+ amounts. One unit amount is approximately 2 mA and is defined as
+ 1X pre-emphasis current.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: 10000
+ maximum: 40000
+
+ qcom,hs-rise-fall-time-bp:
+ description:
+ This adjusts the rise/fall times of the high-speed waveform.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -4100
+ maximum: 5430
+
+ qcom,hs-crossover-voltage-microvolt:
+ description:
+ This adjusts the voltage at which the DP<#> and DM<#>
+ signals cross while transmitting in HS mode.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -31000
+ maximum: 28000
+
+ qcom,hs-output-impedance-micro-ohms:
+ description:
+ In some applications, there can be significant series resistance
+ on the D+ and D- paths between the transceiver and cable. This adjusts
+ the driver source impedance to compensate for added series
+ resistance on the USB. The hardware accepts only discrete values. The
+ value closest to the provided input will be chosen as the override value
+ for this param.
+ minimum: -2300000
+ maximum: 6100000
+
+ qcom,ls-fs-output-impedance-bp:
+ description:
+ This adjusts the low- and full-speed single-ended source
+ impedance while driving high. The following adjustment values are based
+ on nominal process, voltage, and temperature.
+ The hardware accepts only discrete values. The value closest to the
+ provided input will be chosen as the override value for this param.
+ minimum: -1053
+ maximum: 1310
+
required:
- compatible
- reg
--
2.7.4
Add support for overriding electrical signal tuning parameters for
SNPS HS Phy.
Signed-off-by: Krishna Kurapati <[email protected]>
---
drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c | 252 +++++++++++++++++++++++++-
1 file changed, 250 insertions(+), 2 deletions(-)
diff --git a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
index 5d20378..7a0d01c 100644
--- a/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
+++ b/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.c
@@ -52,6 +52,12 @@
#define USB2_SUSPEND_N BIT(2)
#define USB2_SUSPEND_N_SEL BIT(3)
+#define USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X0 (0x6c)
+#define USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X1 (0x70)
+#define USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X2 (0x74)
+#define USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X3 (0x78)
+#define PARAM_OVRD_MASK 0xFF
+
#define USB2_PHY_USB_PHY_CFG0 (0x94)
#define UTMI_PHY_DATAPATH_CTRL_OVERRIDE_EN BIT(0)
#define UTMI_PHY_CMN_CTRL_OVERRIDE_EN BIT(1)
@@ -60,12 +66,47 @@
#define REFCLK_SEL_MASK GENMASK(1, 0)
#define REFCLK_SEL_DEFAULT (0x2 << 0)
+#define HS_DISCONNECT_MASK GENMASK(2, 0)
+#define SQUELCH_DETECTOR_MASK GENMASK(7, 5)
+
+#define HS_AMPLITUDE_MASK GENMASK(3, 0)
+#define PREEMPHASIS_DURATION_MASK BIT(5)
+#define PREEMPHASIS_AMPLITUDE_MASK GENMASK(7, 6)
+
+#define HS_RISE_FALL_MASK GENMASK(1, 0)
+#define HS_CROSSOVER_VOLTAGE_MASK GENMASK(3, 2)
+#define HS_OUTPUT_IMPEDANCE_MASK GENMASK(5, 4)
+
+#define LS_FS_OUTPUT_IMPEDANCE_MASK GENMASK(3, 0)
+
static const char * const qcom_snps_hsphy_vreg_names[] = {
"vdda-pll", "vdda33", "vdda18",
};
#define SNPS_HS_NUM_VREGS ARRAY_SIZE(qcom_snps_hsphy_vreg_names)
+struct override_param {
+ s32 value;
+ u8 reg_val;
+};
+
+struct override_param_map {
+ const char *prop_name;
+ const struct override_param *param_table;
+ u8 table_size;
+ u8 reg_offset;
+ u8 param_mask;
+};
+
+struct phy_override_seq {
+ bool need_update;
+ u8 offset;
+ u8 value;
+ u8 mask;
+};
+
+#define NUM_HSPHY_TUNING_PARAMS (9)
+
/**
* struct qcom_snps_hsphy - snps hs phy attributes
*
@@ -91,6 +132,7 @@ struct qcom_snps_hsphy {
bool phy_initialized;
enum phy_mode mode;
+ struct phy_override_seq update_seq_cfg[NUM_HSPHY_TUNING_PARAMS];
};
static inline void qcom_snps_hsphy_write_mask(void __iomem *base, u32 offset,
@@ -173,10 +215,158 @@ static int qcom_snps_hsphy_set_mode(struct phy *phy, enum phy_mode mode,
return 0;
}
+static const struct override_param hs_disconnect_sc7280[] = {
+ { -272, 0 },
+ { 0, 1 },
+ { 317, 2 },
+ { 630, 3 },
+ { 973, 4 },
+ { 1332, 5 },
+ { 1743, 6 },
+ { 2156, 7 },
+};
+
+static const struct override_param squelch_det_threshold_sc7280[] = {
+ { -2090, 7 },
+ { -1560, 6 },
+ { -1030, 5 },
+ { -530, 4 },
+ { 0, 3 },
+ { 530, 2 },
+ { 1060, 1 },
+ { 1590, 0 },
+};
+
+static const struct override_param hs_amplitude_sc7280[] = {
+ { -660, 0 },
+ { -440, 1 },
+ { -220, 2 },
+ { 0, 3 },
+ { 230, 4 },
+ { 440, 5 },
+ { 650, 6 },
+ { 890, 7 },
+ { 1110, 8 },
+ { 1330, 9 },
+ { 1560, 10 },
+ { 1780, 11 },
+ { 2000, 12 },
+ { 2220, 13 },
+ { 2430, 14 },
+ { 2670, 15 },
+};
+
+static const struct override_param preemphasis_duration_sc7280[] = {
+ { 10000, 1 },
+ { 20000, 0 },
+};
+
+static const struct override_param preemphasis_amplitude_sc7280[] = {
+ { 10000, 1 },
+ { 20000, 2 },
+ { 30000, 3 },
+ { 40000, 0 },
+};
+
+static const struct override_param hs_rise_fall_time_sc7280[] = {
+ { -4100, 3 },
+ { 0, 2 },
+ { 2810, 1 },
+ { 5430, 0 },
+};
+
+static const struct override_param hs_crossover_voltage_sc7280[] = {
+ { -31000, 1 },
+ { 0, 3 },
+ { 28000, 2 },
+};
+
+static const struct override_param hs_output_impedance_sc7280[] = {
+ { -2300000, 3 },
+ { 0, 2 },
+ { 2600000, 1 },
+ { 6100000, 0 },
+};
+
+static const struct override_param ls_fs_output_impedance_sc7280[] = {
+ { -1053, 15 },
+ { -557, 7 },
+ { 0, 3 },
+ { 612, 1 },
+ { 1310, 0 },
+};
+
+static const struct override_param_map sc7280_snps_7nm_phy[] = {
+ {
+ "qcom,hs-disconnect-bp",
+ hs_disconnect_sc7280,
+ ARRAY_SIZE(hs_disconnect_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X0,
+ HS_DISCONNECT_MASK
+ },
+ {
+ "qcom,squelch-detector-bp",
+ squelch_det_threshold_sc7280,
+ ARRAY_SIZE(squelch_det_threshold_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X0,
+ SQUELCH_DETECTOR_MASK
+ },
+ {
+ "qcom,hs-amplitude-bp",
+ hs_amplitude_sc7280,
+ ARRAY_SIZE(hs_amplitude_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X1,
+ HS_AMPLITUDE_MASK
+ },
+ {
+ "qcom,pre-emphasis-duration-bp",
+ preemphasis_duration_sc7280,
+ ARRAY_SIZE(preemphasis_duration_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X1,
+ PREEMPHASIS_DURATION_MASK,
+ },
+ {
+ "qcom,pre-emphasis-amplitude-bp",
+ preemphasis_amplitude_sc7280,
+ ARRAY_SIZE(preemphasis_amplitude_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X1,
+ PREEMPHASIS_AMPLITUDE_MASK,
+ },
+ {
+ "qcom,hs-rise-fall-time-bp",
+ hs_rise_fall_time_sc7280,
+ ARRAY_SIZE(hs_rise_fall_time_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X2,
+ HS_RISE_FALL_MASK
+ },
+ {
+ "qcom,hs-crossover-voltage-microvolt",
+ hs_crossover_voltage_sc7280,
+ ARRAY_SIZE(hs_crossover_voltage_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X2,
+ HS_CROSSOVER_VOLTAGE_MASK
+ },
+ {
+ "qcom,hs-output-impedance-micro-ohms",
+ hs_output_impedance_sc7280,
+ ARRAY_SIZE(hs_output_impedance_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X2,
+ HS_OUTPUT_IMPEDANCE_MASK,
+ },
+ {
+ "qcom,ls-fs-output-impedance-bp",
+ ls_fs_output_impedance_sc7280,
+ ARRAY_SIZE(ls_fs_output_impedance_sc7280),
+ USB2_PHY_USB_PHY_HS_PHY_OVERRIDE_X3,
+ LS_FS_OUTPUT_IMPEDANCE_MASK,
+ },
+ {},
+};
+
static int qcom_snps_hsphy_init(struct phy *phy)
{
struct qcom_snps_hsphy *hsphy = phy_get_drvdata(phy);
- int ret;
+ int ret, i;
dev_vdbg(&phy->dev, "%s(): Initializing SNPS HS phy\n", __func__);
@@ -223,6 +413,14 @@ static int qcom_snps_hsphy_init(struct phy *phy)
qcom_snps_hsphy_write_mask(hsphy->base, USB2_PHY_USB_PHY_HS_PHY_CTRL1,
VBUSVLDEXT0, VBUSVLDEXT0);
+ for (i = 0; i < ARRAY_SIZE(hsphy->update_seq_cfg); i++) {
+ if (hsphy->update_seq_cfg[i].need_update)
+ qcom_snps_hsphy_write_mask(hsphy->base,
+ hsphy->update_seq_cfg[i].offset,
+ hsphy->update_seq_cfg[i].mask,
+ hsphy->update_seq_cfg[i].value);
+ }
+
qcom_snps_hsphy_write_mask(hsphy->base,
USB2_PHY_USB_PHY_HS_PHY_CTRL_COMMON2,
VREGBYPASS, VREGBYPASS);
@@ -280,7 +478,10 @@ static const struct phy_ops qcom_snps_hsphy_gen_ops = {
static const struct of_device_id qcom_snps_hsphy_of_match_table[] = {
{ .compatible = "qcom,sm8150-usb-hs-phy", },
{ .compatible = "qcom,usb-snps-hs-5nm-phy", },
- { .compatible = "qcom,usb-snps-hs-7nm-phy", },
+ {
+ .compatible = "qcom,usb-snps-hs-7nm-phy",
+ .data = &sc7280_snps_7nm_phy,
+ },
{ .compatible = "qcom,usb-snps-femto-v2-phy", },
{ }
};
@@ -291,6 +492,52 @@ static const struct dev_pm_ops qcom_snps_hsphy_pm_ops = {
qcom_snps_hsphy_runtime_resume, NULL)
};
+static void qcom_snps_hsphy_override_param_update_val(
+ const struct override_param_map map,
+ s32 dt_val, struct phy_override_seq *seq_entry)
+{
+ int i;
+
+ /*
+ * Param table for each param is in increasing order
+ * of dt values. We need to iterate over the list to
+ * select the entry that matches the dt value and pick
+ * up the corresponding register value.
+ */
+ for (i = 0; i < map.table_size - 1; i++) {
+ if (map.param_table[i].value == dt_val)
+ break;
+ }
+
+ seq_entry->need_update = true;
+ seq_entry->offset = map.reg_offset;
+ seq_entry->mask = map.param_mask;
+ seq_entry->value = map.param_table[i].reg_val << __ffs(map.param_mask);
+}
+
+static void qcom_snps_hsphy_read_override_param_seq(struct device *dev)
+{
+ struct device_node *node = dev->of_node;
+ s32 val;
+ int ret, i;
+ struct qcom_snps_hsphy *hsphy;
+ const struct override_param_map *cfg = of_device_get_match_data(dev);
+
+ hsphy = dev_get_drvdata(dev);
+
+ for (i = 0; cfg[i].prop_name != NULL; i++) {
+ ret = of_property_read_s32(node, cfg[i].prop_name, &val);
+ if (ret)
+ continue;
+
+ qcom_snps_hsphy_override_param_update_val(cfg[i], val,
+ &hsphy->update_seq_cfg[i]);
+ dev_dbg(&hsphy->phy->dev, "Read param: %s dt_val: %d reg_val: 0x%x\n",
+ cfg[i].prop_name, val, hsphy->update_seq_cfg[i].value);
+
+ }
+}
+
static int qcom_snps_hsphy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -352,6 +599,7 @@ static int qcom_snps_hsphy_probe(struct platform_device *pdev)
dev_set_drvdata(dev, hsphy);
phy_set_drvdata(generic_phy, hsphy);
+ qcom_snps_hsphy_read_override_param_seq(dev);
phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
if (!IS_ERR(phy_provider))
--
2.7.4
Overriding the SNPS Phy tuning parameters for SC7280 IDP device.
Signed-off-by: Krishna Kurapati <[email protected]>
Acked-by: Krzysztof Kozlowski <[email protected]>
---
arch/arm64/boot/dts/qcom/sc7280-idp.dtsi | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi b/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
index 0c48db6..053fd1e 100644
--- a/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc7280-idp.dtsi
@@ -325,6 +325,12 @@
vdda-pll-supply = <&vreg_l10c_0p8>;
vdda33-supply = <&vreg_l2b_3p0>;
vdda18-supply = <&vreg_l1c_1p8>;
+ qcom,hs-rise-fall-time-bp = <0>;
+ qcom,squelch-detector-bp = <(-2090)>;
+ qcom,hs-disconnect-bp = <1743>;
+ qcom,hs-amplitude-bp = <1780>;
+ qcom,hs-crossover-voltage-microvolt = <(-31000)>;
+ qcom,hs-output-impedance-micro-ohms = <2600000>;
};
&usb_1_qmpphy {
--
2.7.4
On Sat, Sep 03, 2022 at 04:00:47PM +0530, Krishna Kurapati wrote:
[..]
> +static void qcom_snps_hsphy_read_override_param_seq(struct device *dev)
> +{
> + struct device_node *node = dev->of_node;
> + s32 val;
> + int ret, i;
> + struct qcom_snps_hsphy *hsphy;
> + const struct override_param_map *cfg = of_device_get_match_data(dev);
Given that you don't have any .data specified for the other compatibles
(which is fine), cfg would be NULL here and below loop would attempt to
access NULL[0].prop_name and crash.
Please add a check for !cfg and just return here.
With that I think the series looks good.
Regards,
Bjorn
On 9/6/2022 8:15 AM, Bjorn Andersson wrote:
> On Sat, Sep 03, 2022 at 04:00:47PM +0530, Krishna Kurapati wrote:
> [..]
>> +static void qcom_snps_hsphy_read_override_param_seq(struct device *dev)
>> +{
>> + struct device_node *node = dev->of_node;
>> + s32 val;
>> + int ret, i;
>> + struct qcom_snps_hsphy *hsphy;
>> + const struct override_param_map *cfg = of_device_get_match_data(dev);
>
> Given that you don't have any .data specified for the other compatibles
> (which is fine), cfg would be NULL here and below loop would attempt to
> access NULL[0].prop_name and crash.
>
> Please add a check for !cfg and just return here.
>
> With that I think the series looks good.
>
> Regards,
> Bjorn
My bad. Missed this before. Thanks for pointing it out.
Will push updated changes.
Thanks,
Krishna,