Re: [Patch 07/19] media: ti-vpe: cal: add CSI2 PHY LDO errata support

From: Hans Verkuil
Date: Mon Oct 21 2019 - 06:38:11 EST


On 10/18/19 5:34 PM, Benoit Parrot wrote:
> Apply Errata i913 every time the functional clock is enabled.
> This should take care of suspend/resume case as well.
>
> Signed-off-by: Benoit Parrot <bparrot@xxxxxx>
> Signed-off-by: Jyri Sarha <jsarha@xxxxxx>
> ---
> drivers/media/platform/ti-vpe/cal.c | 56 +++++++++++++++++++++++-
> drivers/media/platform/ti-vpe/cal_regs.h | 27 ++++++++++++
> 2 files changed, 82 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/ti-vpe/cal.c b/drivers/media/platform/ti-vpe/cal.c
> index 62aeedb705e9..3cbc4dca6de8 100644
> --- a/drivers/media/platform/ti-vpe/cal.c
> +++ b/drivers/media/platform/ti-vpe/cal.c
> @@ -284,6 +284,13 @@ static struct cal_data dra72x_cal_data = {
> .flags = 0,
> };
>
> +static struct cal_data dra72x_es1_cal_data = {
> + .csi2_phy_core = dra72x_cal_csi_phy,
> + .num_csi2_phy = ARRAY_SIZE(dra72x_cal_csi_phy),
> +
> + .flags = DRA72_CAL_PRE_ES2_LDO_DISABLE,
> +};
> +
> /*
> * there is one cal_dev structure in the driver, it is shared by
> * all instances.
> @@ -569,9 +576,52 @@ static void cal_get_hwinfo(struct cal_dev *dev)
> hwinfo);
> }
>
> +/*
> + * Errata i913: CSI2 LDO Needs to be disabled when module is powered on
> + *
> + * Enabling CSI2 LDO shorts it to core supply. It is crucial the 2 CSI2
> + * LDOs on the device are disabled if CSI-2 module is powered on
> + * (0x4845 B304 | 0x4845 B384 [28:27] = 0x1) or in ULPS (0x4845 B304
> + * | 0x4845 B384 [28:27] = 0x2) mode. Common concerns include: high
> + * current draw on the module supply in active mode.
> + *
> + * Errata does not apply when CSI-2 module is powered off
> + * (0x4845 B304 | 0x4845 B384 [28:27] = 0x0).
> + *
> + * SW Workaround:
> + * Set the following register bits to disable the LDO,
> + * which is essentially CSI2 REG10 bit 6:
> + *
> + * Core 0: 0x4845 B828 = 0x0000 0040
> + * Core 1: 0x4845 B928 = 0x0000 0040
> + */
> +static void i913_errata(struct cal_dev *dev, unsigned int port)
> +{
> + u32 reg10 = reg_read(dev->cc[port], CAL_CSI2_PHY_REG10);
> +
> + set_field(&reg10, CAL_CSI2_PHY_REG0_HSCLOCKCONFIG_DISABLE,
> + CAL_CSI2_PHY_REG10_I933_LDO_DISABLE_MASK);
> +
> + cal_dbg(1, dev, "CSI2_%d_REG10 = 0x%08x\n", port, reg10);
> + reg_write(dev->cc[port], CAL_CSI2_PHY_REG10, reg10);
> +}
> +
> static inline int cal_runtime_get(struct cal_dev *dev)

I'd drop the 'inline' here. It doesn't seem appropriate anymore since this
function is now more complex.

Regards,

Hans

> {
> - return pm_runtime_get_sync(&dev->pdev->dev);
> + int r;
> +
> + r = pm_runtime_get_sync(&dev->pdev->dev);
> +
> + if (dev->flags & DRA72_CAL_PRE_ES2_LDO_DISABLE) {
> + /*
> + * Apply errata on both port eveytime we (re-)enable
> + * the clock
> + */
> + i913_errata(dev, 0);
> + i913_errata(dev, 1);
> + }
> +
> + return r;
> }
>
> static inline void cal_runtime_put(struct cal_dev *dev)
> @@ -2071,6 +2121,10 @@ static const struct of_device_id cal_of_match[] = {
> .compatible = "ti,dra72-cal",
> .data = (void *)&dra72x_cal_data,
> },
> + {
> + .compatible = "ti,dra72-pre-es2-cal",
> + .data = (void *)&dra72x_es1_cal_data,
> + },
> {},
> };
> MODULE_DEVICE_TABLE(of, cal_of_match);
> diff --git a/drivers/media/platform/ti-vpe/cal_regs.h b/drivers/media/platform/ti-vpe/cal_regs.h
> index 68cfc922b422..78d6f015c9ea 100644
> --- a/drivers/media/platform/ti-vpe/cal_regs.h
> +++ b/drivers/media/platform/ti-vpe/cal_regs.h
> @@ -10,6 +10,30 @@
> #ifndef __TI_CAL_REGS_H
> #define __TI_CAL_REGS_H
>
> +/*
> + * struct cal_dev.flags possibilities
> + *
> + * DRA72_CAL_PRE_ES2_LDO_DISABLE:
> + * Errata i913: CSI2 LDO Needs to be disabled when module is powered on
> + *
> + * Enabling CSI2 LDO shorts it to core supply. It is crucial the 2 CSI2
> + * LDOs on the device are disabled if CSI-2 module is powered on
> + * (0x4845 B304 | 0x4845 B384 [28:27] = 0x1) or in ULPS (0x4845 B304
> + * | 0x4845 B384 [28:27] = 0x2) mode. Common concerns include: high
> + * current draw on the module supply in active mode.
> + *
> + * Errata does not apply when CSI-2 module is powered off
> + * (0x4845 B304 | 0x4845 B384 [28:27] = 0x0).
> + *
> + * SW Workaround:
> + * Set the following register bits to disable the LDO,
> + * which is essentially CSI2 REG10 bit 6:
> + *
> + * Core 0: 0x4845 B828 = 0x0000 0040
> + * Core 1: 0x4845 B928 = 0x0000 0040
> + */
> +#define DRA72_CAL_PRE_ES2_LDO_DISABLE BIT(0)
> +
> #define CAL_NUM_CSI2_PORTS 2
>
> /* CAL register offsets */
> @@ -71,6 +95,7 @@
> #define CAL_CSI2_PHY_REG0 0x000
> #define CAL_CSI2_PHY_REG1 0x004
> #define CAL_CSI2_PHY_REG2 0x008
> +#define CAL_CSI2_PHY_REG10 0x028
>
> /* CAL Control Module Core Camerrx Control register offsets */
> #define CM_CTRL_CORE_CAMERRX_CONTROL 0x000
> @@ -458,6 +483,8 @@
> #define CAL_CSI2_PHY_REG1_CLOCK_MISS_DETECTOR_STATUS_SUCCESS 0
> #define CAL_CSI2_PHY_REG1_RESET_DONE_STATUS_MASK GENMASK(29, 28)
>
> +#define CAL_CSI2_PHY_REG10_I933_LDO_DISABLE_MASK BIT_MASK(6)
> +
> #define CAL_CSI2_PHY_REG2_CCP2_SYNC_PATTERN_MASK GENMASK(23, 0)
> #define CAL_CSI2_PHY_REG2_TRIGGER_CMD_RXTRIGESC3_MASK GENMASK(25, 24)
> #define CAL_CSI2_PHY_REG2_TRIGGER_CMD_RXTRIGESC2_MASK GENMASK(27, 26)
>