On 4/20/22 08:01, [email protected] wrote:
> From: Nick Hawkins <[email protected]>
>
> Adding support for the HPE GXP Watchdog. It is new to the linux
> community and this along with several other patches is the first
> support for it. The GXP asic contains a full compliment of
> timers one of which is the watchdog timer. The watchdog timer
> is 16 bit and has 10ms resolution. The watchdog is now
Drop "now".
> created as a child device of timer since the same register
> range is used. This was done due to changes requested with
> the device tree.
>
Drop last sentence; it is part of the change log and should stay there.
> ---
Changes made in v3 and v4 are missing.
> v2:
> *Made watchdog a child of timer as they share the same register
> region per change request on dtsi.
> *Removed extra parenthesis
> *Fixed u8 u32 u64 usage
> *Fixed alignment issue
> *Removed unused gxp_wdt_remove function
>
> Signed-off-by: Nick Hawkins <[email protected]>
> ---
> drivers/watchdog/Kconfig | 8 ++
> drivers/watchdog/Makefile | 1 +
> drivers/watchdog/gxp-wdt.c | 166 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 175 insertions(+)
> create mode 100644 drivers/watchdog/gxp-wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index c8fa79da23b3..cb210d2978d2 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -1820,6 +1820,14 @@ config RALINK_WDT
> help
> Hardware driver for the Ralink SoC Watchdog Timer.
>
> +config GXP_WATCHDOG
> + tristate "HPE GXP watchdog support"
> + depends on ARCH_HPE_GXP
> + select WATCHDOG_CORE
> + help
> + Say Y here to include support for the watchdog timer
> + in HPE GXP SoCs.
> +
Add something like:
To compile this driver as a module, choose M here: the
module will be calledgxp_wdt.
> config MT7621_WDT
> tristate "Mediatek SoC watchdog"
> select WATCHDOG_CORE
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index f7da867e8782..e2acf3a0d0fc 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -92,6 +92,7 @@ obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o
> obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
> obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o
> obj-$(CONFIG_ARM_SMC_WATCHDOG) += arm_smc_wdt.o
> +obj-$(CONFIG_GXP_WATCHDOG) += gxp-wdt.o
> obj-$(CONFIG_VISCONTI_WATCHDOG) += visconti_wdt.o
> obj-$(CONFIG_MSC313E_WATCHDOG) += msc313e_wdt.o
> obj-$(CONFIG_APPLE_WATCHDOG) += apple_wdt.o
> diff --git a/drivers/watchdog/gxp-wdt.c b/drivers/watchdog/gxp-wdt.c
> new file mode 100644
> index 000000000000..f45ab9a826d6
> --- /dev/null
> +++ b/drivers/watchdog/gxp-wdt.c
> @@ -0,0 +1,166 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */
> +
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/types.h>
> +#include <linux/watchdog.h>
> +
> +#define MASK_WDGCS_ENABLE 0x01
> +#define MASK_WDGCS_RELOAD 0x04
> +#define MASK_WDGCS_NMIEN 0x08
> +#define MASK_WDGCS_WARN 0x80
> +
> +#define WDT_MAX_TIMEOUT_MS 655000
> +#define WDT_DEFAULT_TIMEOUT 30
> +#define SECS_TO_WDOG_TICKS(x) ((x) * 100)
> +#define WDOG_TICKS_TO_SECS(x) ((x) / 100)
> +
> +#define GXP_WDT_CNT_OFS 0x10
> +#define GXP_WDT_CTRL_OFS 0x16
> +
> +struct gxp_wdt {
> + void __iomem *base;
> + struct watchdog_device wdd;
> +};
> +
> +static void gxp_wdt_enable_reload(struct gxp_wdt *drvdata)
> +{
> + u8 val;
> +
> + val = readb(drvdata->base + GXP_WDT_CTRL_OFS);
> + val |= (MASK_WDGCS_ENABLE | MASK_WDGCS_RELOAD);
> + writeb(val, drvdata->base + GXP_WDT_CTRL_OFS);
> +}
> +
> +static int gxp_wdt_start(struct watchdog_device *wdd)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> +
> + writew(SECS_TO_WDOG_TICKS(wdd->timeout), drvdata->base + GXP_WDT_CNT_OFS);
> + gxp_wdt_enable_reload(drvdata);
> + return 0;
> +}
> +
> +static int gxp_wdt_stop(struct watchdog_device *wdd)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> + u8 val;
> +
> + val = readb_relaxed(drvdata->base + GXP_WDT_CTRL_OFS);
> + val &= ~MASK_WDGCS_ENABLE;
> + writeb(val, drvdata->base + GXP_WDT_CTRL_OFS);
> + return 0;
> +}
> +
> +static int gxp_wdt_set_timeout(struct watchdog_device *wdd,
> + unsigned int timeout)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> + u32 actual;
> +
> + wdd->timeout = timeout;
> + actual = min(timeout, wdd->max_hw_heartbeat_ms / 1000);
> + writew(SECS_TO_WDOG_TICKS(actual), drvdata->base + GXP_WDT_CNT_OFS);
> +
> + return 0;
> +}
> +
> +static unsigned int gxp_wdt_get_timeleft(struct watchdog_device *wdd)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> + u32 val = readw(drvdata->base + GXP_WDT_CNT_OFS);
> +
> + return WDOG_TICKS_TO_SECS(val);
> +}
> +
> +static int gxp_wdt_ping(struct watchdog_device *wdd)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> +
> + gxp_wdt_enable_reload(drvdata);
> + return 0;
> +}
> +
> +static int gxp_restart(struct watchdog_device *wdd, unsigned long action,
> + void *data)
> +{
> + struct gxp_wdt *drvdata = watchdog_get_drvdata(wdd);
> +
> + writew(10, drvdata->base + GXP_WDT_CNT_OFS);
> + gxp_wdt_enable_reload(drvdata);
> + mdelay(100);
> + return 0;
> +}
> +
> +static const struct watchdog_ops gxp_wdt_ops = {
> + .owner = THIS_MODULE,
> + .start = gxp_wdt_start,
> + .stop = gxp_wdt_stop,
> + .ping = gxp_wdt_ping,
> + .set_timeout = gxp_wdt_set_timeout,
> + .get_timeleft = gxp_wdt_get_timeleft,
> + .restart = gxp_restart,
> +};
> +
> +static const struct watchdog_info gxp_wdt_info = {
> + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
> + .identity = "HPE GXP Watchdog timer",
> +};
> +
> +static int gxp_wdt_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct gxp_wdt *drvdata;
> + int err;
> + u8 val;
> +
> + drvdata = devm_kzalloc(dev, sizeof(struct gxp_wdt), GFP_KERNEL);
> + if (!drvdata)
> + return -ENOMEM;
> +
> + drvdata->base = (void __iomem *)dev->platform_data;
> +
> + drvdata->wdd.info = &gxp_wdt_info;
> + drvdata->wdd.ops = &gxp_wdt_ops;
> + drvdata->wdd.max_hw_heartbeat_ms = WDT_MAX_TIMEOUT_MS;
> + drvdata->wdd.parent = dev;
> + drvdata->wdd.timeout = WDT_DEFAULT_TIMEOUT;
> +
> + watchdog_set_drvdata(&drvdata->wdd, drvdata);
> + watchdog_set_nowayout(&drvdata->wdd, WATCHDOG_NOWAYOUT);
> +
> + val = readb(drvdata->base + GXP_WDT_CTRL_OFS);
> +
> + if (val & MASK_WDGCS_ENABLE)
> + set_bit(WDOG_HW_RUNNING, &drvdata->wdd.status);
> +
> + watchdog_set_restart_priority(&drvdata->wdd, 128);
> +
> + watchdog_stop_on_reboot(&drvdata->wdd);
> + err = devm_watchdog_register_device(dev, &drvdata->wdd);
> + if (err) {
> + dev_err(dev, "Failed to register watchdog device");
> + return err;
> + }
> +
> + dev_info(dev, "HPE GXP watchdog timer");
> +
> + return 0;
> +}
> +
> +static struct platform_driver gxp_wdt_driver = {
> + .probe = gxp_wdt_probe,
> + .driver = {
> + .name = "gxp-wdt",
> + },
> +};
> +module_platform_driver(gxp_wdt_driver);
> +
> +MODULE_AUTHOR("Nick Hawkins <[email protected]>");
> +MODULE_AUTHOR("Jean-Marie Verdun <[email protected]>");
> +MODULE_DESCRIPTION("Driver for GXP watchdog timer");
-----Original Message-----
From: Guenter Roeck [mailto:[email protected]] On Behalf Of Guenter Roeck
Sent: Wednesday, April 20, 2022 10:53 AM
To: Hawkins, Nick <[email protected]>; Verdun, Jean-Marie <[email protected]>; Harders, Nick <[email protected]>; [email protected]; [email protected]
Cc: Wim Van Sebroeck <[email protected]>; [email protected]; [email protected]
Subject: Re: [PATCH v4 03/11] drivers: wdt: Introduce HPE GXP SoC Watchdog
On 4/20/22 08:01, [email protected] wrote:
> > From: Nick Hawkins <[email protected]>
> >
> > Adding support for the HPE GXP Watchdog. It is new to the linux
> > community and this along with several other patches is the first
> > support for it. The GXP asic contains a full compliment of timers one
> > of which is the watchdog timer. The watchdog timer is 16 bit and has
> > 10ms resolution. The watchdog is now
> Drop "now".
I have corrected this.
> > created as a child device of timer since the same register range is
> > used. This was done due to changes requested with the device tree.
> >
> Drop last sentence; it is part of the change log and should stay there.
I have corrected this.
> > ---
> Changes made in v3 and v4 are missing.
Fixed, I will fix this on the rest of the patches on this set.
> > +config GXP_WATCHDOG
> > + tristate "HPE GXP watchdog support"
> > + depends on ARCH_HPE_GXP
> > + select WATCHDOG_CORE
> > + help
> > + Say Y here to include support for the watchdog timer
> > + in HPE GXP SoCs.
> > +
> Add something like:
> To compile this driver as a module, choose M here: the
> module will be calledgxp_wdt.
This has been changed. I will look through the rest of the other Kconfigs to make sure this statement is there.
Thanks for the feedback,
-Nick Hawkins