[PATCH 1/4] watchdog: meson: Enable meson SoC specific data
Guenter Roeck
linux at roeck-us.net
Fri Nov 6 14:15:19 PST 2015
On Fri, Nov 06, 2015 at 10:55:03PM +0100, Carlo Caione wrote:
> From: Carlo Caione <carlo at endlessm.com>
>
> With this patch we refactor the driver code to enable watchdog support
> for all platforms based on Amlogic meson SoCs.
>
> Signed-off-by: Carlo Caione <carlo at endlessm.com>
> ---
> drivers/watchdog/meson_wdt.c | 55 ++++++++++++++++++++++++++++++--------------
> 1 file changed, 38 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
> index 1f4155e..89944ed 100644
> --- a/drivers/watchdog/meson_wdt.c
> +++ b/drivers/watchdog/meson_wdt.c
> @@ -19,6 +19,7 @@
> #include <linux/moduleparam.h>
> #include <linux/notifier.h>
> #include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/reboot.h>
> #include <linux/types.h>
> @@ -27,34 +28,45 @@
> #define DRV_NAME "meson_wdt"
>
> #define MESON_WDT_TC 0x00
> -#define MESON_WDT_TC_EN BIT(22)
> -#define MESON_WDT_TC_TM_MASK 0x3fffff
> #define MESON_WDT_DC_RESET (3 << 24)
>
> #define MESON_WDT_RESET 0x04
>
> -#define MESON_WDT_TIMEOUT 30
> +#define MESON_WDT_TIMEOUT 5
> #define MESON_WDT_MIN_TIMEOUT 1
> -#define MESON_WDT_MAX_TIMEOUT (MESON_WDT_TC_TM_MASK / 100000)
>
> -#define MESON_SEC_TO_TC(s) ((s) * 100000)
> +#define MESON_SEC_TO_TC(s, c) ((s) * (c))
>
> static bool nowayout = WATCHDOG_NOWAYOUT;
> static unsigned int timeout = MESON_WDT_TIMEOUT;
>
> +struct meson_wdt_data {
> + unsigned int shift_enable;
> + unsigned int terminal_count_mask;
> + unsigned int count_unit;
> +};
> +
> +static struct meson_wdt_data meson6_wdt_data = {
> + .shift_enable = 22,
I have to admit that I completely fail to understand why it would be
better to move the bit calculation from a constant to runtime.
Can you explain ?
I am also not really a friend of removing definitions, even if they are
only used once. But I understand that this is a matter of opinion.
> + .terminal_count_mask = 0x3fffff,
> + .count_unit = 100000, /* 10 us */
> +};
> +
> struct meson_wdt_dev {
> struct watchdog_device wdt_dev;
> void __iomem *wdt_base;
> struct notifier_block restart_handler;
> + struct meson_wdt_data *data;
> };
>
> static int meson_restart_handle(struct notifier_block *this, unsigned long mode,
> void *cmd)
> {
> - u32 tc_reboot = MESON_WDT_DC_RESET | MESON_WDT_TC_EN;
> + u32 tc_reboot = MESON_WDT_DC_RESET;
> struct meson_wdt_dev *meson_wdt = container_of(this,
> struct meson_wdt_dev,
> restart_handler);
> + tc_reboot |= BIT(meson_wdt->data->shift_enable);
>
I am quite sure that this results in a checkpatch warning.
Did you run your patch through checkpatch ?
> while (1) {
> writel(tc_reboot, meson_wdt->wdt_base + MESON_WDT_TC);
> @@ -80,8 +92,8 @@ static void meson_wdt_change_timeout(struct watchdog_device *wdt_dev,
> u32 reg;
>
> reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
> - reg &= ~MESON_WDT_TC_TM_MASK;
> - reg |= MESON_SEC_TO_TC(timeout);
> + reg &= ~(meson_wdt->data->terminal_count_mask);
Unnecessary ( )
> + reg |= MESON_SEC_TO_TC(timeout, meson_wdt->data->count_unit);
> writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
> }
>
> @@ -102,7 +114,7 @@ static int meson_wdt_stop(struct watchdog_device *wdt_dev)
> u32 reg;
>
> reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
> - reg &= ~MESON_WDT_TC_EN;
> + reg &= ~BIT(meson_wdt->data->shift_enable);
> writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
>
> return 0;
> @@ -117,7 +129,7 @@ static int meson_wdt_start(struct watchdog_device *wdt_dev)
> meson_wdt_ping(wdt_dev);
>
> reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
> - reg |= MESON_WDT_TC_EN;
> + reg |= BIT(meson_wdt->data->shift_enable);
> writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
>
> return 0;
> @@ -138,10 +150,17 @@ static const struct watchdog_ops meson_wdt_ops = {
> .set_timeout = meson_wdt_set_timeout,
> };
>
> +static const struct of_device_id meson_wdt_dt_ids[] = {
> + { .compatible = "amlogic,meson6-wdt", .data = &meson6_wdt_data },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, meson_wdt_dt_ids);
> +
> static int meson_wdt_probe(struct platform_device *pdev)
> {
> struct resource *res;
> struct meson_wdt_dev *meson_wdt;
> + const struct of_device_id *of_id;
> int err;
>
> meson_wdt = devm_kzalloc(&pdev->dev, sizeof(*meson_wdt), GFP_KERNEL);
> @@ -153,11 +172,19 @@ static int meson_wdt_probe(struct platform_device *pdev)
> if (IS_ERR(meson_wdt->wdt_base))
> return PTR_ERR(meson_wdt->wdt_base);
>
> + of_id = of_match_device(meson_wdt_dt_ids, &pdev->dev);
> + if (!of_id) {
> + dev_err(&pdev->dev, "Unable to setup WDT data\n");
"set up" or maybe better initialize.
> + return -ENODEV;
> + }
> + meson_wdt->data = (struct meson_wdt_data *) of_id->data;
Is this typecase necessary ?
> +
> meson_wdt->wdt_dev.parent = &pdev->dev;
> meson_wdt->wdt_dev.info = &meson_wdt_info;
> meson_wdt->wdt_dev.ops = &meson_wdt_ops;
> meson_wdt->wdt_dev.timeout = MESON_WDT_TIMEOUT;
> - meson_wdt->wdt_dev.max_timeout = MESON_WDT_MAX_TIMEOUT;
> + meson_wdt->wdt_dev.max_timeout =
> + meson_wdt->data->terminal_count_mask / meson_wdt->data->count_unit;
> meson_wdt->wdt_dev.min_timeout = MESON_WDT_MIN_TIMEOUT;
>
> watchdog_set_drvdata(&meson_wdt->wdt_dev, meson_wdt);
> @@ -204,12 +231,6 @@ static void meson_wdt_shutdown(struct platform_device *pdev)
> meson_wdt_stop(&meson_wdt->wdt_dev);
> }
>
> -static const struct of_device_id meson_wdt_dt_ids[] = {
> - { .compatible = "amlogic,meson6-wdt" },
> - { /* sentinel */ }
> -};
> -MODULE_DEVICE_TABLE(of, meson_wdt_dt_ids);
> -
> static struct platform_driver meson_wdt_driver = {
> .probe = meson_wdt_probe,
> .remove = meson_wdt_remove,
> --
> 1.9.1
>
> --
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