diff mbox

[2/2] phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800

Message ID 1505729371-6509-1-git-send-email-andrzej.p@samsung.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Andrzej Pietrasiewicz Sept. 18, 2017, 10:09 a.m. UTC
From: Vivek Gautam <gautam.vivek@samsung.com>

Adding phy calibration sequence for USB 3.0 DRD PHY present on
Exynos5420/5800 systems.
This calibration facilitates setting certain PHY parameters viz.
the Loss-of-Signal (LOS) Detector Threshold Level, as well as
Tx-Vboost-Level for Super-Speed operations.
Additionally we also set proper time to wait for RxDetect measurement,
for desired PHY reference clock, so as to solve issue with enumeration
of few USB 3.0 devices, like Samsung SUM-TSB16S 3.0 USB drive
on the controller.

We are using CR_port for this purpose to send required data
to override the LOS values.

On testing with USB 3.0 devices on USB 3.0 port present on
SMDK5420, and peach-pit boards should see following message:
usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd

and without this patch, should see below shown message:
usb 1-1: new high-speed USB device number 2 using xhci-hcd

[Also removed unnecessary extra lines in the register macro definitions]

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
[adapted to use phy_reset as entry point]
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
---
 drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.c                  |   8 +-
 2 files changed, 189 insertions(+), 2 deletions(-)

Comments

Felipe Balbi Sept. 18, 2017, 10:38 a.m. UTC | #1
Hi,

Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
> From: Vivek Gautam <gautam.vivek@samsung.com>
>
> Adding phy calibration sequence for USB 3.0 DRD PHY present on
> Exynos5420/5800 systems.
> This calibration facilitates setting certain PHY parameters viz.
> the Loss-of-Signal (LOS) Detector Threshold Level, as well as
> Tx-Vboost-Level for Super-Speed operations.
> Additionally we also set proper time to wait for RxDetect measurement,
> for desired PHY reference clock, so as to solve issue with enumeration
> of few USB 3.0 devices, like Samsung SUM-TSB16S 3.0 USB drive
> on the controller.
>
> We are using CR_port for this purpose to send required data
> to override the LOS values.
>
> On testing with USB 3.0 devices on USB 3.0 port present on
> SMDK5420, and peach-pit boards should see following message:
> usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd
>
> and without this patch, should see below shown message:
> usb 1-1: new high-speed USB device number 2 using xhci-hcd
>
> [Also removed unnecessary extra lines in the register macro definitions]
>
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> [adapted to use phy_reset as entry point]
> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
> ---
>  drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
>  drivers/usb/dwc3/core.c                  |   8 +-
>  2 files changed, 189 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
> index 7c41daa..f7de067 100644
> --- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
> +++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
> @@ -89,7 +89,17 @@
>  #define PHYCLKRST_COMMONONN			BIT(0)
>  
>  #define EXYNOS5_DRD_PHYREG0			0x14
> +#define PHYREG0_SSC_REF_CLK_SEL			BIT(21)
> +#define PHYREG0_SSC_RANGE			BIT(20)
> +#define PHYREG0_CR_WRITE			BIT(19)
> +#define PHYREG0_CR_READ				BIT(18)
> +#define PHYREG0_CR_DATA_IN(_x)			((_x) << 2)
> +#define PHYREG0_CR_CAP_DATA			BIT(1)
> +#define PHYREG0_CR_CAP_ADDR			BIT(0)
> +
>  #define EXYNOS5_DRD_PHYREG1			0x18
> +#define PHYREG1_CR_DATA_OUT(_x)			((_x) << 1)
> +#define PHYREG1_CR_ACK				BIT(0)
>  
>  #define EXYNOS5_DRD_PHYPARAM0			0x1c
>  
> @@ -118,6 +128,25 @@
>  #define EXYNOS5_DRD_PHYRESUME			0x34
>  #define EXYNOS5_DRD_LINKPORT			0x44
>  
> +/* USB 3.0 DRD PHY SS Function Control Reg; accessed by CR_PORT */
> +#define EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN		(0x15)
> +#define LOSLEVEL_OVRD_IN_LOS_BIAS_5420			(0x5 << 13)
> +#define LOSLEVEL_OVRD_IN_LOS_BIAS_DEFAULT		(0x0 << 13)
> +#define LOSLEVEL_OVRD_IN_EN				(0x1 << 10)
> +#define LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT		(0x9 << 0)
> +
> +#define EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN	(0x12)
> +#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420		(0x5 << 13)
> +#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_DEFAULT		(0x4 << 13)
> +
> +#define EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG		(0x1010)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M		(0x4 << 4)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M		(0x8 << 4)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_25M_26M		(0x8 << 4)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M	(0x20 << 4)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_62M5		(0x20 << 4)
> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_96M_100M		(0x40 << 4)
> +
>  #define KHZ	1000
>  #define MHZ	(KHZ * KHZ)
>  
> @@ -526,6 +555,151 @@ static int exynos5_usbdrd_phy_power_off(struct phy *phy)
>  	return 0;
>  }
>  
> +static int crport_handshake(struct exynos5_usbdrd_phy *phy_drd,
> +						u32 val, u32 cmd)
> +{
> +	u32 usec = 100;
> +	unsigned int result;
> +
> +	writel(val | cmd, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
> +
> +	do {
> +		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
> +		if (result & PHYREG1_CR_ACK)
> +			break;
> +
> +		udelay(1);
> +	} while (usec-- > 0);
> +
> +	if (!usec) {
> +		dev_err(phy_drd->dev,
> +			"CRPORT handshake timeout1 (0x%08x)\n", val);
> +		return -ETIME;
> +	}
> +
> +	usec = 100;
> +
> +	writel(val, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
> +
> +	do {
> +		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
> +		if (!(result & PHYREG1_CR_ACK))
> +			break;
> +
> +		udelay(1);
> +	} while (usec-- > 0);
> +
> +	if (!usec) {
> +		dev_err(phy_drd->dev,
> +			"CRPORT handshake timeout2 (0x%08x)\n", val);
> +		return -ETIME;
> +	}
> +
> +	return 0;
> +}
> +
> +static int crport_ctrl_write(struct exynos5_usbdrd_phy *phy_drd,
> +						u32 addr, u32 data)
> +{
> +	int ret;
> +
> +	/* Write Address */
> +	writel(PHYREG0_CR_DATA_IN(addr),
> +		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(addr),
> +				PHYREG0_CR_CAP_ADDR);
> +	if (ret)
> +		return ret;
> +
> +	/* Write Data */
> +	writel(PHYREG0_CR_DATA_IN(data),
> +		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
> +				PHYREG0_CR_CAP_DATA);
> +	if (ret)
> +		return ret;
> +
> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
> +				PHYREG0_CR_WRITE);
> +
> +	return ret;
> +}
> +
> +/*
> + * Calibrate few PHY parameters using CR_PORT register to meet
> + * SuperSpeed requirements on Exynos5420 and Exynos5800 systems,
> + * which have 28nm USB 3.0 DRD PHY.
> + */
> +static int exynos5420_usbdrd_phy_calibrate(struct exynos5_usbdrd_phy *phy_drd)
> +{
> +	unsigned int temp;
> +	int ret = 0;
> +
> +	/*
> +	 * Change los_bias to (0x5) for 28nm PHY from a
> +	 * default value (0x0); los_level is set as default
> +	 * (0x9) as also reflected in los_level[30:26] bits
> +	 * of PHYPARAM0 register.
> +	 */
> +	temp = LOSLEVEL_OVRD_IN_LOS_BIAS_5420 |
> +		LOSLEVEL_OVRD_IN_EN |
> +		LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT;
> +	ret = crport_ctrl_write(phy_drd,
> +				EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN,
> +				temp);
> +	if (ret) {
> +		dev_err(phy_drd->dev,
> +		 "Failed setting Loss-of-Signal level for SuperSpeed\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * Set tx_vboost_lvl to (0x5) for 28nm PHY Tuning,
> +	 * to raise Tx signal level from its default value of (0x4)
> +	 */
> +	temp = TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420;
> +	ret = crport_ctrl_write(phy_drd,
> +				EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN,
> +				temp);
> +	if (ret) {
> +		dev_err(phy_drd->dev,
> +		 "Failed setting Tx-Vboost-Level for SuperSpeed\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * Set proper time to wait for RxDetect measurement, for
> +	 * desired reference clock of PHY, by tuning the CR_PORT
> +	 * register LANE0.TX_DEBUG which is internal to PHY.
> +	 * This fixes issue with few USB 3.0 devices, which are
> +	 * not detected (not even generate interrupts on the bus
> +	 * on insertion) without this change.
> +	 * e.g. Samsung SUM-TSB16S 3.0 USB drive.
> +	 */
> +	switch (phy_drd->extrefclk) {
> +	case EXYNOS5_FSEL_50MHZ:
> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M;
> +		break;
> +	case EXYNOS5_FSEL_20MHZ:
> +	case EXYNOS5_FSEL_19MHZ2:
> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M;
> +		break;
> +	case EXYNOS5_FSEL_24MHZ:
> +	default:
> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M;
> +		break;
> +	}
> +
> +	ret = crport_ctrl_write(phy_drd,
> +				EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG,
> +				temp);
> +	if (ret)
> +		dev_err(phy_drd->dev,
> +		 "Failed setting RxDetect measurement time for SuperSpeed\n");
> +
> +	return ret;
> +}
> +
>  static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
>  					struct of_phandle_args *args)
>  {
> @@ -537,11 +711,20 @@ static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
>  	return phy_drd->phys[args->args[0]].phy;
>  }
>  
> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
> +{
> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
> +
> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
> +}
> +
>  static const struct phy_ops exynos5_usbdrd_phy_ops = {
>  	.init		= exynos5_usbdrd_phy_init,
>  	.exit		= exynos5_usbdrd_phy_exit,
>  	.power_on	= exynos5_usbdrd_phy_power_on,
>  	.power_off	= exynos5_usbdrd_phy_power_off,
> +	.reset		= exynos5_usbdrd_phy_reset,
>  	.owner		= THIS_MODULE,
>  };
>  
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 03474d3..1d5836e 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>  		} else {
>  			if (dwc->usb2_phy)
>  				otg_set_vbus(dwc->usb2_phy->otg, true);
> -			if (dwc->usb2_generic_phy)
> +			if (dwc->usb2_generic_phy) {
>  				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
> -
> +				phy_reset(dwc->usb2_generic_phy);

it doesn't look like this is the best place to reset the phy. Also,
->reset() doesn't seem to match correctly with a calibration. That seems
to be more fitting to a ->power_on() or ->init() implementation.

Kishon, any comments?
Kishon Vijay Abraham I Sept. 18, 2017, 11:06 a.m. UTC | #2
Hi,

On Monday 18 September 2017 04:08 PM, Felipe Balbi wrote:
> 
> Hi,
> 
> Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>> From: Vivek Gautam <gautam.vivek@samsung.com>
>>
>> Adding phy calibration sequence for USB 3.0 DRD PHY present on
>> Exynos5420/5800 systems.
>> This calibration facilitates setting certain PHY parameters viz.
>> the Loss-of-Signal (LOS) Detector Threshold Level, as well as
>> Tx-Vboost-Level for Super-Speed operations.
>> Additionally we also set proper time to wait for RxDetect measurement,
>> for desired PHY reference clock, so as to solve issue with enumeration
>> of few USB 3.0 devices, like Samsung SUM-TSB16S 3.0 USB drive
>> on the controller.
>>
>> We are using CR_port for this purpose to send required data
>> to override the LOS values.
>>
>> On testing with USB 3.0 devices on USB 3.0 port present on
>> SMDK5420, and peach-pit boards should see following message:
>> usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd
>>
>> and without this patch, should see below shown message:
>> usb 1-1: new high-speed USB device number 2 using xhci-hcd
>>
>> [Also removed unnecessary extra lines in the register macro definitions]
>>
>> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
>> [adapted to use phy_reset as entry point]
>> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
>> ---
>>  drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
>>  drivers/usb/dwc3/core.c                  |   8 +-
>>  2 files changed, 189 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
>> index 7c41daa..f7de067 100644
>> --- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
>> +++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
>> @@ -89,7 +89,17 @@
>>  #define PHYCLKRST_COMMONONN			BIT(0)
>>  
>>  #define EXYNOS5_DRD_PHYREG0			0x14
>> +#define PHYREG0_SSC_REF_CLK_SEL			BIT(21)
>> +#define PHYREG0_SSC_RANGE			BIT(20)
>> +#define PHYREG0_CR_WRITE			BIT(19)
>> +#define PHYREG0_CR_READ				BIT(18)
>> +#define PHYREG0_CR_DATA_IN(_x)			((_x) << 2)
>> +#define PHYREG0_CR_CAP_DATA			BIT(1)
>> +#define PHYREG0_CR_CAP_ADDR			BIT(0)
>> +
>>  #define EXYNOS5_DRD_PHYREG1			0x18
>> +#define PHYREG1_CR_DATA_OUT(_x)			((_x) << 1)
>> +#define PHYREG1_CR_ACK				BIT(0)
>>  
>>  #define EXYNOS5_DRD_PHYPARAM0			0x1c
>>  
>> @@ -118,6 +128,25 @@
>>  #define EXYNOS5_DRD_PHYRESUME			0x34
>>  #define EXYNOS5_DRD_LINKPORT			0x44
>>  
>> +/* USB 3.0 DRD PHY SS Function Control Reg; accessed by CR_PORT */
>> +#define EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN		(0x15)
>> +#define LOSLEVEL_OVRD_IN_LOS_BIAS_5420			(0x5 << 13)
>> +#define LOSLEVEL_OVRD_IN_LOS_BIAS_DEFAULT		(0x0 << 13)
>> +#define LOSLEVEL_OVRD_IN_EN				(0x1 << 10)
>> +#define LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT		(0x9 << 0)
>> +
>> +#define EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN	(0x12)
>> +#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420		(0x5 << 13)
>> +#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_DEFAULT		(0x4 << 13)
>> +
>> +#define EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG		(0x1010)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M		(0x4 << 4)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M		(0x8 << 4)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_25M_26M		(0x8 << 4)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M	(0x20 << 4)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_62M5		(0x20 << 4)
>> +#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_96M_100M		(0x40 << 4)
>> +
>>  #define KHZ	1000
>>  #define MHZ	(KHZ * KHZ)
>>  
>> @@ -526,6 +555,151 @@ static int exynos5_usbdrd_phy_power_off(struct phy *phy)
>>  	return 0;
>>  }
>>  
>> +static int crport_handshake(struct exynos5_usbdrd_phy *phy_drd,
>> +						u32 val, u32 cmd)
>> +{
>> +	u32 usec = 100;
>> +	unsigned int result;
>> +
>> +	writel(val | cmd, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
>> +
>> +	do {
>> +		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
>> +		if (result & PHYREG1_CR_ACK)
>> +			break;
>> +
>> +		udelay(1);
>> +	} while (usec-- > 0);
>> +
>> +	if (!usec) {
>> +		dev_err(phy_drd->dev,
>> +			"CRPORT handshake timeout1 (0x%08x)\n", val);
>> +		return -ETIME;
>> +	}
>> +
>> +	usec = 100;
>> +
>> +	writel(val, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
>> +
>> +	do {
>> +		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
>> +		if (!(result & PHYREG1_CR_ACK))
>> +			break;
>> +
>> +		udelay(1);
>> +	} while (usec-- > 0);
>> +
>> +	if (!usec) {
>> +		dev_err(phy_drd->dev,
>> +			"CRPORT handshake timeout2 (0x%08x)\n", val);
>> +		return -ETIME;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int crport_ctrl_write(struct exynos5_usbdrd_phy *phy_drd,
>> +						u32 addr, u32 data)
>> +{
>> +	int ret;
>> +
>> +	/* Write Address */
>> +	writel(PHYREG0_CR_DATA_IN(addr),
>> +		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
>> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(addr),
>> +				PHYREG0_CR_CAP_ADDR);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* Write Data */
>> +	writel(PHYREG0_CR_DATA_IN(data),
>> +		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
>> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
>> +				PHYREG0_CR_CAP_DATA);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
>> +				PHYREG0_CR_WRITE);
>> +
>> +	return ret;
>> +}
>> +
>> +/*
>> + * Calibrate few PHY parameters using CR_PORT register to meet
>> + * SuperSpeed requirements on Exynos5420 and Exynos5800 systems,
>> + * which have 28nm USB 3.0 DRD PHY.
>> + */
>> +static int exynos5420_usbdrd_phy_calibrate(struct exynos5_usbdrd_phy *phy_drd)
>> +{
>> +	unsigned int temp;
>> +	int ret = 0;
>> +
>> +	/*
>> +	 * Change los_bias to (0x5) for 28nm PHY from a
>> +	 * default value (0x0); los_level is set as default
>> +	 * (0x9) as also reflected in los_level[30:26] bits
>> +	 * of PHYPARAM0 register.
>> +	 */
>> +	temp = LOSLEVEL_OVRD_IN_LOS_BIAS_5420 |
>> +		LOSLEVEL_OVRD_IN_EN |
>> +		LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT;
>> +	ret = crport_ctrl_write(phy_drd,
>> +				EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN,
>> +				temp);
>> +	if (ret) {
>> +		dev_err(phy_drd->dev,
>> +		 "Failed setting Loss-of-Signal level for SuperSpeed\n");
>> +		return ret;
>> +	}
>> +
>> +	/*
>> +	 * Set tx_vboost_lvl to (0x5) for 28nm PHY Tuning,
>> +	 * to raise Tx signal level from its default value of (0x4)
>> +	 */
>> +	temp = TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420;
>> +	ret = crport_ctrl_write(phy_drd,
>> +				EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN,
>> +				temp);
>> +	if (ret) {
>> +		dev_err(phy_drd->dev,
>> +		 "Failed setting Tx-Vboost-Level for SuperSpeed\n");
>> +		return ret;
>> +	}
>> +
>> +	/*
>> +	 * Set proper time to wait for RxDetect measurement, for
>> +	 * desired reference clock of PHY, by tuning the CR_PORT
>> +	 * register LANE0.TX_DEBUG which is internal to PHY.
>> +	 * This fixes issue with few USB 3.0 devices, which are
>> +	 * not detected (not even generate interrupts on the bus
>> +	 * on insertion) without this change.
>> +	 * e.g. Samsung SUM-TSB16S 3.0 USB drive.
>> +	 */
>> +	switch (phy_drd->extrefclk) {
>> +	case EXYNOS5_FSEL_50MHZ:
>> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M;
>> +		break;
>> +	case EXYNOS5_FSEL_20MHZ:
>> +	case EXYNOS5_FSEL_19MHZ2:
>> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M;
>> +		break;
>> +	case EXYNOS5_FSEL_24MHZ:
>> +	default:
>> +		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M;
>> +		break;
>> +	}
>> +
>> +	ret = crport_ctrl_write(phy_drd,
>> +				EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG,
>> +				temp);
>> +	if (ret)
>> +		dev_err(phy_drd->dev,
>> +		 "Failed setting RxDetect measurement time for SuperSpeed\n");
>> +
>> +	return ret;
>> +}
>> +
>>  static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
>>  					struct of_phandle_args *args)
>>  {
>> @@ -537,11 +711,20 @@ static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
>>  	return phy_drd->phys[args->args[0]].phy;
>>  }
>>  
>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>> +{
>> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
>> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>> +
>> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
>> +}
>> +
>>  static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>  	.init		= exynos5_usbdrd_phy_init,
>>  	.exit		= exynos5_usbdrd_phy_exit,
>>  	.power_on	= exynos5_usbdrd_phy_power_on,
>>  	.power_off	= exynos5_usbdrd_phy_power_off,
>> +	.reset		= exynos5_usbdrd_phy_reset,
>>  	.owner		= THIS_MODULE,
>>  };
>>  
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index 03474d3..1d5836e 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>  		} else {
>>  			if (dwc->usb2_phy)
>>  				otg_set_vbus(dwc->usb2_phy->otg, true);
>> -			if (dwc->usb2_generic_phy)
>> +			if (dwc->usb2_generic_phy) {
>>  				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>> -
>> +				phy_reset(dwc->usb2_generic_phy);
> 
> it doesn't look like this is the best place to reset the phy. Also,

right, phy_reset is done during initialization before phy_power_on/phy_init or
in error cases.

> ->reset() doesn't seem to match correctly with a calibration. That seems
> to be more fitting to a ->power_on() or ->init() implementation.

yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
modified.

Thanks
Kishon
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Andrzej Pietrasiewicz Sept. 18, 2017, 11:27 a.m. UTC | #3
W dniu 18.09.2017 o 13:06, Kishon Vijay Abraham I pisze:
> Hi,
> 
> On Monday 18 September 2017 04:08 PM, Felipe Balbi wrote:
>>
>> Hi,
>>
>> Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>>> From: Vivek Gautam <gautam.vivek@samsung.com>
>>>
>>> Adding phy calibration sequence for USB 3.0 DRD PHY present on
>>> Exynos5420/5800 systems.

<snip>

>>>   
>>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>>> +{
>>> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
>>> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>>> +
>>> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
>>> +}
>>> +
>>>   static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>>   	.init		= exynos5_usbdrd_phy_init,
>>>   	.exit		= exynos5_usbdrd_phy_exit,
>>>   	.power_on	= exynos5_usbdrd_phy_power_on,
>>>   	.power_off	= exynos5_usbdrd_phy_power_off,
>>> +	.reset		= exynos5_usbdrd_phy_reset,
>>>   	.owner		= THIS_MODULE,
>>>   };
>>>   
>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>> index 03474d3..1d5836e 100644
>>> --- a/drivers/usb/dwc3/core.c
>>> +++ b/drivers/usb/dwc3/core.c
>>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>>   		} else {
>>>   			if (dwc->usb2_phy)
>>>   				otg_set_vbus(dwc->usb2_phy->otg, true);
>>> -			if (dwc->usb2_generic_phy)
>>> +			if (dwc->usb2_generic_phy) {
>>>   				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>>> -
>>> +				phy_reset(dwc->usb2_generic_phy);
>>
>> it doesn't look like this is the best place to reset the phy. Also,
> 
> right, phy_reset is done during initialization before phy_power_on/phy_init or
> in error cases.
> 
>> ->reset() doesn't seem to match correctly with a calibration. That seems
>> to be more fitting to a ->power_on() or ->init() implementation.
> 
> yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
> modified.

The original patch used a hack like below, in xhci_plat_probe():

+       /* Initialize and power-on USB 3.0 PHY */
+       xhci->shared_hcd->phy->init_count = 0;
+       ret = phy_init(xhci->shared_hcd->phy);
+       if (ret)
+               goto dealloc_usb3_hcd;
+
+       xhci->shared_hcd->phy->power_count = 0;
+       ret = phy_power_on(xhci->shared_hcd->phy);
+       if (ret) {
+               phy_exit(xhci->shared_hcd->phy);
+               goto dealloc_usb3_hcd;
+       }
+

Manually setting init_count to 0 in order for the subsequent phy_init() to
happen probably does not look good.

The calibration is clearly needed. However, I don't have any strong opinions
on from which place exactly to trigger the calibration process.
The original patch did not make it upstream, but if that patch is ok,
it is perfectly fine with me to drop my version and take that one instead.

Andrzej
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Andrzej Pietrasiewicz Sept. 18, 2017, 11:41 a.m. UTC | #4
Hi,

W dniu 18.09.2017 o 13:27, Andrzej Pietrasiewicz pisze:
> W dniu 18.09.2017 o 13:06, Kishon Vijay Abraham I pisze:
>> Hi,
>>
>> On Monday 18 September 2017 04:08 PM, Felipe Balbi wrote:
>>>
>>> Hi,
>>>
>>> Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>>>> From: Vivek Gautam <gautam.vivek@samsung.com>
>>>>
>>>> Adding phy calibration sequence for USB 3.0 DRD PHY present on
>>>> Exynos5420/5800 systems.
> 
> <snip>
> 
>>>>    
>>>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>>>> +{
>>>> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
>>>> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>>>> +
>>>> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
>>>> +}
>>>> +
>>>>    static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>>>    	.init		= exynos5_usbdrd_phy_init,
>>>>    	.exit		= exynos5_usbdrd_phy_exit,
>>>>    	.power_on	= exynos5_usbdrd_phy_power_on,
>>>>    	.power_off	= exynos5_usbdrd_phy_power_off,
>>>> +	.reset		= exynos5_usbdrd_phy_reset,
>>>>    	.owner		= THIS_MODULE,
>>>>    };
>>>>    
>>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>>> index 03474d3..1d5836e 100644
>>>> --- a/drivers/usb/dwc3/core.c
>>>> +++ b/drivers/usb/dwc3/core.c
>>>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>>>    		} else {
>>>>    			if (dwc->usb2_phy)
>>>>    				otg_set_vbus(dwc->usb2_phy->otg, true);
>>>> -			if (dwc->usb2_generic_phy)
>>>> +			if (dwc->usb2_generic_phy) {
>>>>    				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>>>> -
>>>> +				phy_reset(dwc->usb2_generic_phy);
>>>
>>> it doesn't look like this is the best place to reset the phy. Also,
>>
>> right, phy_reset is done during initialization before phy_power_on/phy_init or
>> in error cases.
>>
>>> ->reset() doesn't seem to match correctly with a calibration. That seems
>>> to be more fitting to a ->power_on() or ->init() implementation.
>>
>> yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
>> modified.
> 
> The original patch used a hack like below, in xhci_plat_probe():
> 
> +       /* Initialize and power-on USB 3.0 PHY */
> +       xhci->shared_hcd->phy->init_count = 0;
> +       ret = phy_init(xhci->shared_hcd->phy);
> +       if (ret)
> +               goto dealloc_usb3_hcd;
> +
> +       xhci->shared_hcd->phy->power_count = 0;
> +       ret = phy_power_on(xhci->shared_hcd->phy);
> +       if (ret) {
> +               phy_exit(xhci->shared_hcd->phy);
> +               goto dealloc_usb3_hcd;
> +       }
> +
> 
> Manually setting init_count to 0 in order for the subsequent phy_init() to
> happen probably does not look good.
> 
> The calibration is clearly needed. However, I don't have any strong opinions
> on from which place exactly to trigger the calibration process.
> The original patch did not make it upstream, but if that patch is ok,
> it is perfectly fine with me to drop my version and take that one instead.

Me bad, I did not write about an important issue.
The calibration must happen after usb_add_hcd(), otherwise
usb_add_hcd() indirectly triggers overwriting the effects of calibration.

Andrzej

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Felipe Balbi Sept. 18, 2017, 12:43 p.m. UTC | #5
Hi,

Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>>>>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>>>>> +{
>>>>> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
>>>>> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>>>>> +
>>>>> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
>>>>> +}
>>>>> +
>>>>>    static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>>>>    	.init		= exynos5_usbdrd_phy_init,
>>>>>    	.exit		= exynos5_usbdrd_phy_exit,
>>>>>    	.power_on	= exynos5_usbdrd_phy_power_on,
>>>>>    	.power_off	= exynos5_usbdrd_phy_power_off,
>>>>> +	.reset		= exynos5_usbdrd_phy_reset,
>>>>>    	.owner		= THIS_MODULE,
>>>>>    };
>>>>>    
>>>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>>>> index 03474d3..1d5836e 100644
>>>>> --- a/drivers/usb/dwc3/core.c
>>>>> +++ b/drivers/usb/dwc3/core.c
>>>>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>>>>    		} else {
>>>>>    			if (dwc->usb2_phy)
>>>>>    				otg_set_vbus(dwc->usb2_phy->otg, true);
>>>>> -			if (dwc->usb2_generic_phy)
>>>>> +			if (dwc->usb2_generic_phy) {
>>>>>    				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>>>>> -
>>>>> +				phy_reset(dwc->usb2_generic_phy);
>>>>
>>>> it doesn't look like this is the best place to reset the phy. Also,
>>>
>>> right, phy_reset is done during initialization before phy_power_on/phy_init or
>>> in error cases.
>>>
>>>> ->reset() doesn't seem to match correctly with a calibration. That seems
>>>> to be more fitting to a ->power_on() or ->init() implementation.
>>>
>>> yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
>>> modified.
>> 
>> The original patch used a hack like below, in xhci_plat_probe():
>> 
>> +       /* Initialize and power-on USB 3.0 PHY */
>> +       xhci->shared_hcd->phy->init_count = 0;
>> +       ret = phy_init(xhci->shared_hcd->phy);
>> +       if (ret)
>> +               goto dealloc_usb3_hcd;
>> +
>> +       xhci->shared_hcd->phy->power_count = 0;
>> +       ret = phy_power_on(xhci->shared_hcd->phy);
>> +       if (ret) {
>> +               phy_exit(xhci->shared_hcd->phy);
>> +               goto dealloc_usb3_hcd;
>> +       }
>> +
>> 
>> Manually setting init_count to 0 in order for the subsequent phy_init() to
>> happen probably does not look good.
>> 
>> The calibration is clearly needed. However, I don't have any strong opinions
>> on from which place exactly to trigger the calibration process.
>> The original patch did not make it upstream, but if that patch is ok,
>> it is perfectly fine with me to drop my version and take that one instead.
>
> Me bad, I did not write about an important issue.
> The calibration must happen after usb_add_hcd(), otherwise
> usb_add_hcd() indirectly triggers overwriting the effects of calibration.

in that case, you should do that from xhci-plat indeed. I think the
whole idea with init_count is just to make sure you don't initialize it
twice.

One thing's for sure, ->reset() doesn't seem to be the matching callback
for you to use and, given your explanation above, dwc3 doesn't seem to
be the right place to fiddle with that.

Seems like we need an extension of the generic PHY framework to cope
with your requirement.
Andrzej Pietrasiewicz Sept. 18, 2017, 2:20 p.m. UTC | #6
Hi,

W dniu 18.09.2017 o 14:43, Felipe Balbi pisze:
> 
> Hi,
> 
> Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>>>>>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>>>>>> +{
>>>>>> +	struct phy_usb_instance *inst = phy_get_drvdata(phy);
>>>>>> +	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>>>>>> +
>>>>>> +	return exynos5420_usbdrd_phy_calibrate(phy_drd);
>>>>>> +}
>>>>>> +
>>>>>>     static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>>>>>     	.init		= exynos5_usbdrd_phy_init,
>>>>>>     	.exit		= exynos5_usbdrd_phy_exit,
>>>>>>     	.power_on	= exynos5_usbdrd_phy_power_on,
>>>>>>     	.power_off	= exynos5_usbdrd_phy_power_off,
>>>>>> +	.reset		= exynos5_usbdrd_phy_reset,
>>>>>>     	.owner		= THIS_MODULE,
>>>>>>     };
>>>>>>     
>>>>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>>>>> index 03474d3..1d5836e 100644
>>>>>> --- a/drivers/usb/dwc3/core.c
>>>>>> +++ b/drivers/usb/dwc3/core.c
>>>>>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>>>>>     		} else {
>>>>>>     			if (dwc->usb2_phy)
>>>>>>     				otg_set_vbus(dwc->usb2_phy->otg, true);
>>>>>> -			if (dwc->usb2_generic_phy)
>>>>>> +			if (dwc->usb2_generic_phy) {
>>>>>>     				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>>>>>> -
>>>>>> +				phy_reset(dwc->usb2_generic_phy);
>>>>>
>>>>> it doesn't look like this is the best place to reset the phy. Also,
>>>>
>>>> right, phy_reset is done during initialization before phy_power_on/phy_init or
>>>> in error cases.
>>>>
>>>>> ->reset() doesn't seem to match correctly with a calibration. That seems
>>>>> to be more fitting to a ->power_on() or ->init() implementation.
>>>>
>>>> yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
>>>> modified.
>>>
>>> The original patch used a hack like below, in xhci_plat_probe():
>>>
>>> +       /* Initialize and power-on USB 3.0 PHY */
>>> +       xhci->shared_hcd->phy->init_count = 0;
>>> +       ret = phy_init(xhci->shared_hcd->phy);
>>> +       if (ret)
>>> +               goto dealloc_usb3_hcd;
>>> +
>>> +       xhci->shared_hcd->phy->power_count = 0;
>>> +       ret = phy_power_on(xhci->shared_hcd->phy);
>>> +       if (ret) {
>>> +               phy_exit(xhci->shared_hcd->phy);
>>> +               goto dealloc_usb3_hcd;
>>> +       }
>>> +
>>>
>>> Manually setting init_count to 0 in order for the subsequent phy_init() to
>>> happen probably does not look good.
>>>
>>> The calibration is clearly needed. However, I don't have any strong opinions
>>> on from which place exactly to trigger the calibration process.
>>> The original patch did not make it upstream, but if that patch is ok,
>>> it is perfectly fine with me to drop my version and take that one instead.
>>
>> Me bad, I did not write about an important issue.
>> The calibration must happen after usb_add_hcd(), otherwise
>> usb_add_hcd() indirectly triggers overwriting the effects of calibration.
> 
> in that case, you should do that from xhci-plat indeed. I think the
> whole idea with init_count is just to make sure you don't initialize it
> twice.

As far as I understand the code in question the desired result is exactly the opposite:
to make sure it _does_ initialize twice, otherwise after the first initialization the
calibration results were lost. In other words, in the code snippet above,
in xhci_plat_probe() the phy_init() was creatively (ab)used in order to force
the calibration at a desired moment, while in the original invocation of phy_init()
the calibration result was merely a short-term side effect discarded soon afterwards.

> 
> One thing's for sure, ->reset() doesn't seem to be the matching callback
> for you to use and, given your explanation above, dwc3 doesn't seem to
> be the right place to fiddle with that.
> 
> Seems like we need an extension of the generic PHY framework to cope
> with your requirement.
>

Here are old patches from Vivek:

https://lkml.org/lkml/2014/9/2/166

In particular:

https://lkml.org/lkml/2014/9/2/170

Please see the discussion that follows the latter.

All in all, is adding the calibrate() method to phy_ops the way to go or not?

Andrzej
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Kishon Vijay Abraham I Sept. 21, 2017, 11:07 a.m. UTC | #7
Hi,

On Monday 18 September 2017 07:50 PM, Andrzej Pietrasiewicz wrote:
> Hi,
> 
> W dniu 18.09.2017 o 14:43, Felipe Balbi pisze:
>>
>> Hi,
>>
>> Andrzej Pietrasiewicz <andrzej.p@samsung.com> writes:
>>>>>>> +static int exynos5_usbdrd_phy_reset(struct phy *phy)
>>>>>>> +{
>>>>>>> +    struct phy_usb_instance *inst = phy_get_drvdata(phy);
>>>>>>> +    struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
>>>>>>> +
>>>>>>> +    return exynos5420_usbdrd_phy_calibrate(phy_drd);
>>>>>>> +}
>>>>>>> +
>>>>>>>     static const struct phy_ops exynos5_usbdrd_phy_ops = {
>>>>>>>         .init        = exynos5_usbdrd_phy_init,
>>>>>>>         .exit        = exynos5_usbdrd_phy_exit,
>>>>>>>         .power_on    = exynos5_usbdrd_phy_power_on,
>>>>>>>         .power_off    = exynos5_usbdrd_phy_power_off,
>>>>>>> +    .reset        = exynos5_usbdrd_phy_reset,
>>>>>>>         .owner        = THIS_MODULE,
>>>>>>>     };
>>>>>>>     diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>>>>>>> index 03474d3..1d5836e 100644
>>>>>>> --- a/drivers/usb/dwc3/core.c
>>>>>>> +++ b/drivers/usb/dwc3/core.c
>>>>>>> @@ -156,9 +156,10 @@ static void __dwc3_set_mode(struct work_struct *work)
>>>>>>>             } else {
>>>>>>>                 if (dwc->usb2_phy)
>>>>>>>                     otg_set_vbus(dwc->usb2_phy->otg, true);
>>>>>>> -            if (dwc->usb2_generic_phy)
>>>>>>> +            if (dwc->usb2_generic_phy) {
>>>>>>>                     phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>>>>>>> -
>>>>>>> +                phy_reset(dwc->usb2_generic_phy);
>>>>>>
>>>>>> it doesn't look like this is the best place to reset the phy. Also,
>>>>>
>>>>> right, phy_reset is done during initialization before
>>>>> phy_power_on/phy_init or
>>>>> in error cases.
>>>>>
>>>>>> ->reset() doesn't seem to match correctly with a calibration. That seems
>>>>>> to be more fitting to a ->power_on() or ->init() implementation.
>>>>>
>>>>> yeah, the initial patch seems to calibrate in phy_init(). Not sure why it's
>>>>> modified.
>>>>
>>>> The original patch used a hack like below, in xhci_plat_probe():
>>>>
>>>> +       /* Initialize and power-on USB 3.0 PHY */
>>>> +       xhci->shared_hcd->phy->init_count = 0;
>>>> +       ret = phy_init(xhci->shared_hcd->phy);
>>>> +       if (ret)
>>>> +               goto dealloc_usb3_hcd;
>>>> +
>>>> +       xhci->shared_hcd->phy->power_count = 0;
>>>> +       ret = phy_power_on(xhci->shared_hcd->phy);
>>>> +       if (ret) {
>>>> +               phy_exit(xhci->shared_hcd->phy);
>>>> +               goto dealloc_usb3_hcd;
>>>> +       }
>>>> +
>>>>
>>>> Manually setting init_count to 0 in order for the subsequent phy_init() to
>>>> happen probably does not look good.
>>>>
>>>> The calibration is clearly needed. However, I don't have any strong opinions
>>>> on from which place exactly to trigger the calibration process.
>>>> The original patch did not make it upstream, but if that patch is ok,
>>>> it is perfectly fine with me to drop my version and take that one instead.
>>>
>>> Me bad, I did not write about an important issue.
>>> The calibration must happen after usb_add_hcd(), otherwise
>>> usb_add_hcd() indirectly triggers overwriting the effects of calibration.
>>
>> in that case, you should do that from xhci-plat indeed. I think the
>> whole idea with init_count is just to make sure you don't initialize it
>> twice.
> 
> As far as I understand the code in question the desired result is exactly the
> opposite:
> to make sure it _does_ initialize twice, otherwise after the first
> initialization the
> calibration results were lost. In other words, in the code snippet above,
> in xhci_plat_probe() the phy_init() was creatively (ab)used in order to force
> the calibration at a desired moment, while in the original invocation of
> phy_init()
> the calibration result was merely a short-term side effect discarded soon
> afterwards.
> 
>>
>> One thing's for sure, ->reset() doesn't seem to be the matching callback
>> for you to use and, given your explanation above, dwc3 doesn't seem to
>> be the right place to fiddle with that.
>>
>> Seems like we need an extension of the generic PHY framework to cope
>> with your requirement.
>>
> 
> Here are old patches from Vivek:
> 
> https://lkml.org/lkml/2014/9/2/166
> 
> In particular:
> 
> https://lkml.org/lkml/2014/9/2/170
> 
> Please see the discussion that follows the latter.
> 
> All in all, is adding the calibrate() method to phy_ops the way to go or not?

Adding calibrate is fine but doing init() and power_on() in one driver and
calibrate() in another doesn't look correct. Why not let xhci do init() and
power_on() of phy instead of dwc3?

Thanks
Kishon
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Andrzej Pietrasiewicz Oct. 3, 2017, 12:59 p.m. UTC | #8
Hi all,

This is the second version of patches in this thread.

The series fixes problems with enumerating of SuperSpeed devices
on an Odroid XU3. There was a patch series from Vivek Gautam in
circulation, but it got lost somehow. Please see:

https://lkml.org/lkml/2014/9/2/166
https://lkml.org/lkml/2015/2/2/257

I adapted his patch so that it does not use a hacky solution to force
additional initialization in order for calibration to happen.
With this patch enumeration happens correctly and a super speed device
is recognized as such.

@Kishon:

As far as I understand what you suggest is to move phy_init() and
phy_power_on() invocations from dwc3/core.c to xhci-plat, but,
to the best of my knowledge, they are needed in device mode, too.

Changes since v1:

- added calibrate() callback to phy
- used calibrate() instead of reset() to trigger the calibration

Andrzej Pietrasiewicz (1):
  drivers: phy: add calibrate method

Vivek Gautam (1):
  phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800

 drivers/phy/phy-core.c                   |  14 +++
 drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.c                  |   7 +-
 include/linux/phy/phy.h                  |  10 ++
 4 files changed, 212 insertions(+), 2 deletions(-)
Andrzej Pietrasiewicz Oct. 3, 2017, 1:19 p.m. UTC | #9
W dniu 03.10.2017 o 14:59, Andrzej Pietrasiewicz pisze:
> Hi all,
> 
> This is the second version of patches in this thread.
> 

I have lost the subject of the cover letter.
Should be "dwc3 on XU3". I did not resend the series in order
not to spam the recipients. Sorry for confusion.

Andrzej
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Kishon Vijay Abraham I Oct. 4, 2017, 4:22 a.m. UTC | #10
Hi,

On Tuesday 03 October 2017 06:29 PM, Andrzej Pietrasiewicz wrote:
> Hi all,
> 
> This is the second version of patches in this thread.
> 
> The series fixes problems with enumerating of SuperSpeed devices
> on an Odroid XU3. There was a patch series from Vivek Gautam in
> circulation, but it got lost somehow. Please see:
> 
> https://lkml.org/lkml/2014/9/2/166
> https://lkml.org/lkml/2015/2/2/257
> 
> I adapted his patch so that it does not use a hacky solution to force
> additional initialization in order for calibration to happen.
> With this patch enumeration happens correctly and a super speed device
> is recognized as such.
> 
> @Kishon:
> 
> As far as I understand what you suggest is to move phy_init() and
> phy_power_on() invocations from dwc3/core.c to xhci-plat, but,
> to the best of my knowledge, they are needed in device mode, too.

What I meant is perform phy initializations for host mode in xhci and keep only
device mode phy initialization in dwc3.

Thanks
Kishon
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Andrzej Pietrasiewicz Oct. 4, 2017, 7:05 a.m. UTC | #11
Hi,

W dniu 04.10.2017 o 06:22, Kishon Vijay Abraham I pisze:
> Hi,
> 

<snip>

>>
>> @Kishon:
>>
>> As far as I understand what you suggest is to move phy_init() and
>> phy_power_on() invocations from dwc3/core.c to xhci-plat, but,
>> to the best of my knowledge, they are needed in device mode, too.
> 
> What I meant is perform phy initializations for host mode in xhci and keep only
> device mode phy initialization in dwc3.
> 

Ah, I should have been more explicit.
Unfortunately, without phy initialization dwc3 registers are unavailable,
so it looks like it is really needed at the point it is done now.

Andrzej
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Andrzej Pietrasiewicz Oct. 5, 2017, 12:11 p.m. UTC | #12
Hi all,

This is the third version of patches in this thread.

The series fixes problems with enumerating of SuperSpeed devices
on an Odroid XU3. There was a patch series from Vivek Gautam in
circulation, but it got lost somehow. Please see:

https://lkml.org/lkml/2014/9/2/166
https://lkml.org/lkml/2015/2/2/257

I adapted his patch so that it does not use a hacky solution to force
additional initialization in order for calibration to happen.
With this patch enumeration happens correctly and a super speed device
is recognized as such.

Changes since v2:

- exported the "calibrate_phy" symbol

Changes since v1:

- added calibrate() callback to phy
- used calibrate() instead of reset() to trigger the calibration


Andrzej Pietrasiewicz (1):
  drivers: phy: add calibrate method

Vivek Gautam (1):
  phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800

 drivers/phy/phy-core.c                   |  15 +++
 drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.c                  |   7 +-
 include/linux/phy/phy.h                  |  10 ++
 4 files changed, 213 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
index 7c41daa..f7de067 100644
--- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
+++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
@@ -89,7 +89,17 @@ 
 #define PHYCLKRST_COMMONONN			BIT(0)
 
 #define EXYNOS5_DRD_PHYREG0			0x14
+#define PHYREG0_SSC_REF_CLK_SEL			BIT(21)
+#define PHYREG0_SSC_RANGE			BIT(20)
+#define PHYREG0_CR_WRITE			BIT(19)
+#define PHYREG0_CR_READ				BIT(18)
+#define PHYREG0_CR_DATA_IN(_x)			((_x) << 2)
+#define PHYREG0_CR_CAP_DATA			BIT(1)
+#define PHYREG0_CR_CAP_ADDR			BIT(0)
+
 #define EXYNOS5_DRD_PHYREG1			0x18
+#define PHYREG1_CR_DATA_OUT(_x)			((_x) << 1)
+#define PHYREG1_CR_ACK				BIT(0)
 
 #define EXYNOS5_DRD_PHYPARAM0			0x1c
 
@@ -118,6 +128,25 @@ 
 #define EXYNOS5_DRD_PHYRESUME			0x34
 #define EXYNOS5_DRD_LINKPORT			0x44
 
+/* USB 3.0 DRD PHY SS Function Control Reg; accessed by CR_PORT */
+#define EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN		(0x15)
+#define LOSLEVEL_OVRD_IN_LOS_BIAS_5420			(0x5 << 13)
+#define LOSLEVEL_OVRD_IN_LOS_BIAS_DEFAULT		(0x0 << 13)
+#define LOSLEVEL_OVRD_IN_EN				(0x1 << 10)
+#define LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT		(0x9 << 0)
+
+#define EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN	(0x12)
+#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420		(0x5 << 13)
+#define TX_VBOOSTLEVEL_OVRD_IN_VBOOST_DEFAULT		(0x4 << 13)
+
+#define EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG		(0x1010)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M		(0x4 << 4)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M		(0x8 << 4)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_25M_26M		(0x8 << 4)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M	(0x20 << 4)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_62M5		(0x20 << 4)
+#define LANE0_TX_DEBUG_RXDET_MEAS_TIME_96M_100M		(0x40 << 4)
+
 #define KHZ	1000
 #define MHZ	(KHZ * KHZ)
 
@@ -526,6 +555,151 @@  static int exynos5_usbdrd_phy_power_off(struct phy *phy)
 	return 0;
 }
 
+static int crport_handshake(struct exynos5_usbdrd_phy *phy_drd,
+						u32 val, u32 cmd)
+{
+	u32 usec = 100;
+	unsigned int result;
+
+	writel(val | cmd, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
+
+	do {
+		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
+		if (result & PHYREG1_CR_ACK)
+			break;
+
+		udelay(1);
+	} while (usec-- > 0);
+
+	if (!usec) {
+		dev_err(phy_drd->dev,
+			"CRPORT handshake timeout1 (0x%08x)\n", val);
+		return -ETIME;
+	}
+
+	usec = 100;
+
+	writel(val, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
+
+	do {
+		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
+		if (!(result & PHYREG1_CR_ACK))
+			break;
+
+		udelay(1);
+	} while (usec-- > 0);
+
+	if (!usec) {
+		dev_err(phy_drd->dev,
+			"CRPORT handshake timeout2 (0x%08x)\n", val);
+		return -ETIME;
+	}
+
+	return 0;
+}
+
+static int crport_ctrl_write(struct exynos5_usbdrd_phy *phy_drd,
+						u32 addr, u32 data)
+{
+	int ret;
+
+	/* Write Address */
+	writel(PHYREG0_CR_DATA_IN(addr),
+		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
+	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(addr),
+				PHYREG0_CR_CAP_ADDR);
+	if (ret)
+		return ret;
+
+	/* Write Data */
+	writel(PHYREG0_CR_DATA_IN(data),
+		phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
+	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
+				PHYREG0_CR_CAP_DATA);
+	if (ret)
+		return ret;
+
+	ret = crport_handshake(phy_drd, PHYREG0_CR_DATA_IN(data),
+				PHYREG0_CR_WRITE);
+
+	return ret;
+}
+
+/*
+ * Calibrate few PHY parameters using CR_PORT register to meet
+ * SuperSpeed requirements on Exynos5420 and Exynos5800 systems,
+ * which have 28nm USB 3.0 DRD PHY.
+ */
+static int exynos5420_usbdrd_phy_calibrate(struct exynos5_usbdrd_phy *phy_drd)
+{
+	unsigned int temp;
+	int ret = 0;
+
+	/*
+	 * Change los_bias to (0x5) for 28nm PHY from a
+	 * default value (0x0); los_level is set as default
+	 * (0x9) as also reflected in los_level[30:26] bits
+	 * of PHYPARAM0 register.
+	 */
+	temp = LOSLEVEL_OVRD_IN_LOS_BIAS_5420 |
+		LOSLEVEL_OVRD_IN_EN |
+		LOSLEVEL_OVRD_IN_LOS_LEVEL_DEFAULT;
+	ret = crport_ctrl_write(phy_drd,
+				EXYNOS5_DRD_PHYSS_LOSLEVEL_OVRD_IN,
+				temp);
+	if (ret) {
+		dev_err(phy_drd->dev,
+		 "Failed setting Loss-of-Signal level for SuperSpeed\n");
+		return ret;
+	}
+
+	/*
+	 * Set tx_vboost_lvl to (0x5) for 28nm PHY Tuning,
+	 * to raise Tx signal level from its default value of (0x4)
+	 */
+	temp = TX_VBOOSTLEVEL_OVRD_IN_VBOOST_5420;
+	ret = crport_ctrl_write(phy_drd,
+				EXYNOS5_DRD_PHYSS_TX_VBOOSTLEVEL_OVRD_IN,
+				temp);
+	if (ret) {
+		dev_err(phy_drd->dev,
+		 "Failed setting Tx-Vboost-Level for SuperSpeed\n");
+		return ret;
+	}
+
+	/*
+	 * Set proper time to wait for RxDetect measurement, for
+	 * desired reference clock of PHY, by tuning the CR_PORT
+	 * register LANE0.TX_DEBUG which is internal to PHY.
+	 * This fixes issue with few USB 3.0 devices, which are
+	 * not detected (not even generate interrupts on the bus
+	 * on insertion) without this change.
+	 * e.g. Samsung SUM-TSB16S 3.0 USB drive.
+	 */
+	switch (phy_drd->extrefclk) {
+	case EXYNOS5_FSEL_50MHZ:
+		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_48M_50M_52M;
+		break;
+	case EXYNOS5_FSEL_20MHZ:
+	case EXYNOS5_FSEL_19MHZ2:
+		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_19M2_20M;
+		break;
+	case EXYNOS5_FSEL_24MHZ:
+	default:
+		temp = LANE0_TX_DEBUG_RXDET_MEAS_TIME_24M;
+		break;
+	}
+
+	ret = crport_ctrl_write(phy_drd,
+				EXYNOS5_DRD_PHYSS_LANE0_TX_DEBUG,
+				temp);
+	if (ret)
+		dev_err(phy_drd->dev,
+		 "Failed setting RxDetect measurement time for SuperSpeed\n");
+
+	return ret;
+}
+
 static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
 					struct of_phandle_args *args)
 {
@@ -537,11 +711,20 @@  static struct phy *exynos5_usbdrd_phy_xlate(struct device *dev,
 	return phy_drd->phys[args->args[0]].phy;
 }
 
+static int exynos5_usbdrd_phy_reset(struct phy *phy)
+{
+	struct phy_usb_instance *inst = phy_get_drvdata(phy);
+	struct exynos5_usbdrd_phy *phy_drd = to_usbdrd_phy(inst);
+
+	return exynos5420_usbdrd_phy_calibrate(phy_drd);
+}
+
 static const struct phy_ops exynos5_usbdrd_phy_ops = {
 	.init		= exynos5_usbdrd_phy_init,
 	.exit		= exynos5_usbdrd_phy_exit,
 	.power_on	= exynos5_usbdrd_phy_power_on,
 	.power_off	= exynos5_usbdrd_phy_power_off,
+	.reset		= exynos5_usbdrd_phy_reset,
 	.owner		= THIS_MODULE,
 };
 
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 03474d3..1d5836e 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -156,9 +156,10 @@  static void __dwc3_set_mode(struct work_struct *work)
 		} else {
 			if (dwc->usb2_phy)
 				otg_set_vbus(dwc->usb2_phy->otg, true);
-			if (dwc->usb2_generic_phy)
+			if (dwc->usb2_generic_phy) {
 				phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
-
+				phy_reset(dwc->usb2_generic_phy);
+			}
 		}
 		break;
 	case DWC3_GCTL_PRTCAP_DEVICE:
@@ -955,6 +956,9 @@  static int dwc3_core_init_mode(struct dwc3 *dwc)
 				dev_err(dev, "failed to initialize host\n");
 			return ret;
 		}
+
+		if (dwc->usb2_generic_phy)
+			phy_reset(dwc->usb2_generic_phy);
 		break;
 	case USB_DR_MODE_OTG:
 		INIT_WORK(&dwc->drd_work, __dwc3_set_mode);