Re: [PATCH v3 09/11] thermal: armada: Wait sensors validity before exiting the init callback

Gregory CLEMENT
2017-12-14T11:23:23Z

Hi Miquel,

On jeu., déc. 14 2017, Miquel Raynal <miquel.raynal@free-electrons.com> wrote:

> The thermal core will check for sensors validity right after the
> initialization callback has returned. As the initialization routine make
> a reset, the sensors are not ready immediately and the core spawns an
> error in the dmesg. Avoid this annoying situation by polling on the
> validity bit before exiting from these routines. This also avoid the use
> of blind sleeps.

You only modified the armada 380 and ap806 init function. Does it means
that this feature is not supported on the other variant?

Gregory

>
> Suggested-by: David Sniatkiwicz <davidsn@marvell.com>
> Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
> ---
> drivers/thermal/armada_thermal.c | 23 ++++++++++++++++++++---
> 1 file changed, 20 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c
> index be141ca53e83..1c4122f7377c 100644
> --- a/drivers/thermal/armada_thermal.c
> +++ b/drivers/thermal/armada_thermal.c
> @@ -23,6 +23,7 @@
> #include <linux/platform_device.h>
> #include <linux/of_device.h>
> #include <linux/thermal.h>
> +#include <linux/iopoll.h>
>
> /* Thermal Manager Control and Status Register */
> #define PMU_TDC0_SW_RST_MASK (0x1 << 1)
> @@ -59,6 +60,9 @@
> #define CONTROL1_EXT_TSEN_SW_RESET BIT(7)
> #define CONTROL1_EXT_TSEN_HW_RESETn BIT(8)
>
> +#define STATUS_POLL_PERIOD_US 1000
> +#define STATUS_POLL_TIMEOUT_US 100000
> +
> struct armada_thermal_data;
>
> /* Marvell EBU Thermal Sensor Dev Structure */
> @@ -154,6 +158,16 @@ static void armada375_init_sensor(struct platform_device *pdev,
> msleep(50);
> }
>
> +static void armada_wait_sensor_validity(struct armada_thermal_priv *priv)
> +{
> + u32 reg;
> +
> + readl_relaxed_poll_timeout(priv->status, reg,
> + reg & priv->data->is_valid_bit,
> + STATUS_POLL_PERIOD_US,
> + STATUS_POLL_TIMEOUT_US);
> +}
> +
> static void armada380_init_sensor(struct platform_device *pdev,
> struct armada_thermal_priv *priv)
> {
> @@ -163,7 +177,6 @@ static void armada380_init_sensor(struct platform_device *pdev,
> reg |= CONTROL1_EXT_TSEN_HW_RESETn;
> reg &= ~CONTROL1_EXT_TSEN_SW_RESET;
> writel(reg, priv->control1);
> - msleep(10);
>
> /* Set Tsen Tc Trim to correct default value (errata #132698) */
> if (priv->control0) {
> @@ -171,8 +184,10 @@ static void armada380_init_sensor(struct platform_device *pdev,
> reg &= ~CONTROL0_TSEN_TC_TRIM_MASK;
> reg |= CONTROL0_TSEN_TC_TRIM_VAL;
> writel(reg, priv->control0);
> - msleep(10);
> }
> +
> + /* Wait the sensors to be valid or the core will warn the user */
> + armada_wait_sensor_validity(priv);
> }
>
> static void armada_ap806_init_sensor(struct platform_device *pdev,
> @@ -190,7 +205,9 @@ static void armada_ap806_init_sensor(struct platform_device *pdev,
> reg &= ~CONTROL0_TSEN_RESET;
> reg |= CONTROL0_TSEN_START | CONTROL0_TSEN_ENABLE;
> writel(reg, priv->control0);
> - msleep(10);
> +
> + /* Wait the sensors to be valid or the core will warn the user */
> + armada_wait_sensor_validity(priv);
> }
>
> static bool armada_is_valid(struct armada_thermal_priv *priv)
> --
> 2.11.0
>
>
> _______________________________________________
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> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.