Use the bark interrupt as the pre-timeout notifier whenever this
interrupt is available.
By default, the pretimeout notification shall occur one second earlier
than the timeout.
Signed-off-by: Jorge Ramirez-Ortiz <[email protected]>
---
v4:
address Guenter Roeck comments as follows:
remove unnecessary include and private variable
provide macro for WDT EN register values
use pretimeout as per its API intent
handle EPROBE_DEFER on get_irq
also:
handle the irq registration as done in pm8916_wdt.c
v3:
remove unnecesary variable added to private.
v2:
register the pre-timeout notifier instead.
v1:
drivers/watchdog/qcom-wdt.c | 64 ++++++++++++++++++++++++++++++++++---
1 file changed, 59 insertions(+), 5 deletions(-)
diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
index 7be7f87be28f..0f1d29eeb81d 100644
--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -10,6 +10,7 @@
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/of_device.h>
+#include <linux/interrupt.h>
enum wdt_reg {
WDT_RST,
@@ -19,6 +20,9 @@ enum wdt_reg {
WDT_BITE_TIME,
};
+#define QCOM_WDT_ENABLE BIT(0)
+#define QCOM_WDT_ENABLE_IRQ BIT(1)
+
static const u32 reg_offset_data_apcs_tmr[] = {
[WDT_RST] = 0x38,
[WDT_EN] = 0x40,
@@ -54,15 +58,38 @@ struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd)
return container_of(wdd, struct qcom_wdt, wdd);
}
+static inline int qcom_get_enable(struct watchdog_device *wdd)
+{
+ int enable = QCOM_WDT_ENABLE;
+
+ if (wdd->info->options & WDIOF_PRETIMEOUT)
+ enable |= QCOM_WDT_ENABLE_IRQ;
+
+ return enable;
+}
+
+static irqreturn_t qcom_wdt_isr(int irq, void *arg)
+{
+ struct watchdog_device *wdd = arg;
+
+ watchdog_notify_pretimeout(wdd);
+
+ return IRQ_HANDLED;
+}
+
static int qcom_wdt_start(struct watchdog_device *wdd)
{
struct qcom_wdt *wdt = to_qcom_wdt(wdd);
+ unsigned int bark = wdd->timeout;
+
+ if (wdd->pretimeout)
+ bark = bark - wdd->pretimeout;
writel(0, wdt_addr(wdt, WDT_EN));
writel(1, wdt_addr(wdt, WDT_RST));
- writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
+ writel(bark * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
- writel(1, wdt_addr(wdt, WDT_EN));
+ writel(qcom_get_enable(wdd), wdt_addr(wdt, WDT_EN));
return 0;
}
@@ -89,6 +116,13 @@ static int qcom_wdt_set_timeout(struct watchdog_device *wdd,
return qcom_wdt_start(wdd);
}
+static int qcom_wdt_set_pretimeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ wdd->pretimeout = timeout;
+ return qcom_wdt_start(wdd);
+}
+
static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action,
void *data)
{
@@ -105,7 +139,7 @@ static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action,
writel(1, wdt_addr(wdt, WDT_RST));
writel(timeout, wdt_addr(wdt, WDT_BARK_TIME));
writel(timeout, wdt_addr(wdt, WDT_BITE_TIME));
- writel(1, wdt_addr(wdt, WDT_EN));
+ writel(qcom_get_enable(wdd), wdt_addr(wdt, WDT_EN));
/*
* Actually make sure the above sequence hits hardware before sleeping.
@@ -121,6 +155,7 @@ static const struct watchdog_ops qcom_wdt_ops = {
.stop = qcom_wdt_stop,
.ping = qcom_wdt_ping,
.set_timeout = qcom_wdt_set_timeout,
+ .set_pretimeout = qcom_wdt_set_pretimeout,
.restart = qcom_wdt_restart,
.owner = THIS_MODULE,
};
@@ -133,6 +168,15 @@ static const struct watchdog_info qcom_wdt_info = {
.identity = KBUILD_MODNAME,
};
+static const struct watchdog_info qcom_wdt_pt_info = {
+ .options = WDIOF_KEEPALIVEPING
+ | WDIOF_MAGICCLOSE
+ | WDIOF_SETTIMEOUT
+ | WDIOF_PRETIMEOUT
+ | WDIOF_CARDRESET,
+ .identity = KBUILD_MODNAME,
+};
+
static void qcom_clk_disable_unprepare(void *data)
{
clk_disable_unprepare(data);
@@ -146,7 +190,7 @@ static int qcom_wdt_probe(struct platform_device *pdev)
struct device_node *np = dev->of_node;
const u32 *regs;
u32 percpu_offset;
- int ret;
+ int irq, ret;
regs = of_device_get_match_data(dev);
if (!regs) {
@@ -204,7 +248,17 @@ static int qcom_wdt_probe(struct platform_device *pdev)
return -EINVAL;
}
- wdt->wdd.info = &qcom_wdt_info;
+ irq = platform_get_irq(pdev, 0);
+ if (irq > 0) {
+ if (devm_request_irq(dev, irq, qcom_wdt_isr,
+ IRQF_TRIGGER_RISING, "wdt_bark",
+ &wdt->wdd))
+ irq = 0;
+ } else if (irq == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ wdt->wdd.info = irq > 0 ? &qcom_wdt_pt_info : &qcom_wdt_info;
+ wdt->wdd.pretimeout = irq > 0 ? 1 : 0;
wdt->wdd.ops = &qcom_wdt_ops;
wdt->wdd.min_timeout = 1;
wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
--
2.23.0
On Thu 05 Sep 14:00 PDT 2019, Jorge Ramirez-Ortiz wrote:
> diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
[..]
> +static inline int qcom_get_enable(struct watchdog_device *wdd)
> +{
> + int enable = QCOM_WDT_ENABLE;
> +
> + if (wdd->info->options & WDIOF_PRETIMEOUT)
> + enable |= QCOM_WDT_ENABLE_IRQ;
Looking at downstream they conditionally write 3 to WDT_EN during
initialization, but during suspend/resume they just set it to back to 1.
So I don't think you should touch BIT(1) (which name doesn't match
downstream or the register documentation)
> +
> + return enable;
> +}
> +
> +static irqreturn_t qcom_wdt_isr(int irq, void *arg)
> +{
> + struct watchdog_device *wdd = arg;
> +
> + watchdog_notify_pretimeout(wdd);
> +
> + return IRQ_HANDLED;
> +}
> +
> static int qcom_wdt_start(struct watchdog_device *wdd)
> {
> struct qcom_wdt *wdt = to_qcom_wdt(wdd);
> + unsigned int bark = wdd->timeout;
> +
> + if (wdd->pretimeout)
> + bark = bark - wdd->pretimeout;
As Guenter points out, writing wdd->timeout - wdt->pretimeout to
WDT_BARK_TIME unconditionally should do the trick.
>
> writel(0, wdt_addr(wdt, WDT_EN));
> writel(1, wdt_addr(wdt, WDT_RST));
> - writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
> + writel(bark * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
> writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
> - writel(1, wdt_addr(wdt, WDT_EN));
> + writel(qcom_get_enable(wdd), wdt_addr(wdt, WDT_EN));
> return 0;
> }
[..]
> @@ -204,7 +248,17 @@ static int qcom_wdt_probe(struct platform_device *pdev)
> return -EINVAL;
> }
>
> - wdt->wdd.info = &qcom_wdt_info;
> + irq = platform_get_irq(pdev, 0);
> + if (irq > 0) {
> + if (devm_request_irq(dev, irq, qcom_wdt_isr,
> + IRQF_TRIGGER_RISING, "wdt_bark",
> + &wdt->wdd))
A failure here means that a irq was specified in DT (platform_get_irq()
returned > 0) but you failed to acquire request it, you should fail your
probe() when this happens.
> + irq = 0;
> + } else if (irq == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
Some {} around this block please.
Regards,
Bjorn
> +
> + wdt->wdd.info = irq > 0 ? &qcom_wdt_pt_info : &qcom_wdt_info;
> + wdt->wdd.pretimeout = irq > 0 ? 1 : 0;
> wdt->wdd.ops = &qcom_wdt_ops;
> wdt->wdd.min_timeout = 1;
> wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
> --
> 2.23.0
>
On Fri, Sep 06, 2019 at 10:40:09AM -0700, Bjorn Andersson wrote:
> On Thu 05 Sep 14:00 PDT 2019, Jorge Ramirez-Ortiz wrote:
> > diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
> [..]
> > +static inline int qcom_get_enable(struct watchdog_device *wdd)
> > +{
> > + int enable = QCOM_WDT_ENABLE;
> > +
> > + if (wdd->info->options & WDIOF_PRETIMEOUT)
> > + enable |= QCOM_WDT_ENABLE_IRQ;
>
> Looking at downstream they conditionally write 3 to WDT_EN during
> initialization, but during suspend/resume they just set it to back to 1.
>
Looks like a bug to me.
Either case, per API, pretimeout is enabled with the value of pretimeout,
not with interrupt information from DT. I am not inclined to accept the
above condition for enabling it.
> So I don't think you should touch BIT(1) (which name doesn't match
> downstream or the register documentation)
>
You mean touching bit 1 is wrong to start with, and it is not a bit used
to enable the interrupt (and thus pretimeout) ?
Guess I'll need to dig out the manual myself.
Guenter
On 9/6/19 19:40, Bjorn Andersson wrote:
> On Thu 05 Sep 14:00 PDT 2019, Jorge Ramirez-Ortiz wrote:
>> diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
> [..]
>> +static inline int qcom_get_enable(struct watchdog_device *wdd)
>> +{
>> + int enable = QCOM_WDT_ENABLE;
>> +
>> + if (wdd->info->options & WDIOF_PRETIMEOUT)
>> + enable |= QCOM_WDT_ENABLE_IRQ;
>
> Looking at downstream they conditionally write 3 to WDT_EN during
> initialization, but during suspend/resume they just set it to back to 1.
>
> So I don't think you should touch BIT(1) (which name doesn't match
> downstream or the register documentation)
writing BIT(1) on the enable register is necessary to get the interrupt
and therefore to be notified of the bark event. this can not be avoided.
>
>> +
>> + return enable;
>> +}
>> +
>> +static irqreturn_t qcom_wdt_isr(int irq, void *arg)
>> +{
>> + struct watchdog_device *wdd = arg;
>> +
>> + watchdog_notify_pretimeout(wdd);
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> static int qcom_wdt_start(struct watchdog_device *wdd)
>> {
>> struct qcom_wdt *wdt = to_qcom_wdt(wdd);
>> + unsigned int bark = wdd->timeout;
>> +
>> + if (wdd->pretimeout)
>> + bark = bark - wdd->pretimeout;
>
> As Guenter points out, writing wdd->timeout - wdt->pretimeout to
> WDT_BARK_TIME unconditionally should do the trick.
yes
>
>>
>> writel(0, wdt_addr(wdt, WDT_EN));
>> writel(1, wdt_addr(wdt, WDT_RST));
>> - writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
>> + writel(bark * wdt->rate, wdt_addr(wdt, WDT_BARK_TIME));
>> writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
>> - writel(1, wdt_addr(wdt, WDT_EN));
>> + writel(qcom_get_enable(wdd), wdt_addr(wdt, WDT_EN));
>> return 0;
>> }
> [..]
>> @@ -204,7 +248,17 @@ static int qcom_wdt_probe(struct platform_device *pdev)
>> return -EINVAL;
>> }
>>
>> - wdt->wdd.info = &qcom_wdt_info;
>> + irq = platform_get_irq(pdev, 0);
>> + if (irq > 0) {
>> + if (devm_request_irq(dev, irq, qcom_wdt_isr,
>> + IRQF_TRIGGER_RISING, "wdt_bark",
>> + &wdt->wdd))
>
> A failure here means that a irq was specified in DT (platform_get_irq()
> returned > 0) but you failed to acquire request it, you should fail your
> probe() when this happens.
yeah that is what I thought but since pm8916-wdt.c has recently been
merged exactly like I copied above I chose to follow to avoid arguing
about this.
anyway I'll send a patch to fix pm8916-wdt.c and then will do it that
same way on this driver.
>
>> + irq = 0;
>> + } else if (irq == -EPROBE_DEFER)
>> + return -EPROBE_DEFER;
>
> Some {} around this block please.
um, checkpatch didnt complain. anyway sure, will do
>
> Regards,
> Bjorn
>
>> +
>> + wdt->wdd.info = irq > 0 ? &qcom_wdt_pt_info : &qcom_wdt_info;
>> + wdt->wdd.pretimeout = irq > 0 ? 1 : 0;
>> wdt->wdd.ops = &qcom_wdt_ops;
>> wdt->wdd.min_timeout = 1;
>> wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
>> --
>> 2.23.0
>>
>