Re: [PATCH 1/3] watchdog: rzg2l_wdt: Fix reboot for RZ/V2M

From: Wim Van Sebroeck
Date: Sun May 07 2023 - 13:31:47 EST


Hi Fabrizio,

Based on below e-mail I excluded this patch from the merge window.
I saw that Guenter still has it in his branch.
So can we have an update on this please?

Thanks in advance,
Wim.

> Hi Geert and Guenter,
>
> Thank you for your reviews!
>
> As it turns out, the rzg2l_wdt driver has some reset related issues
> (currently not addressed by the driver) for the RZ/V2M and RZ/Five
> SoCs. More specifically to this patch, there is a better way to fix
> the restart callback by addressing the way the reset is handled
> for the watchdog IP.
>
> I am dropping this patch, and I'll send out a series to address
> the above concerns (which will tackle the issues with the restart
> callback in a better way).
>
>
> Thanks,
> Fab
>
>
> > From: Guenter Roeck <groeck7@xxxxxxxxx> On Behalf Of Guenter Roeck
> > Sent: 15 November 2022 13:28
> > Subject: Re: [PATCH 1/3] watchdog: rzg2l_wdt: Fix reboot for RZ/V2M
> >
> > On Thu, Nov 03, 2022 at 10:39:54PM +0000, Fabrizio Castro wrote:
> > > The setting for the RZ/V2M watchdog cannot be changed once
> > > the watchdog has been enabled, unless the IP gets reset.
> > > The current implementation of the restart callback assumes
> > > that the watchdog is not enabled, but that's not always the
> > > case, and it leads to longer than necessary reboot times if
> > > the watchdog is already running.
> > >
> > > Always reset the RZ/V2M watchdog first, so that we can always
> > > restart quickly.
> > >
> > > Fixes: ec122fd94eeb ("watchdog: rzg2l_wdt: Add rzv2m support")
> > > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
> >
> > Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> >
> > > ---
> > > drivers/watchdog/rzg2l_wdt.c | 11 ++++++++---
> > > 1 file changed, 8 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c
> > > index 974a4194a8fd..00438ceed17a 100644
> > > --- a/drivers/watchdog/rzg2l_wdt.c
> > > +++ b/drivers/watchdog/rzg2l_wdt.c
> > > @@ -145,10 +145,10 @@ static int rzg2l_wdt_restart(struct
> > watchdog_device *wdev,
> > > {
> > > struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev);
> > >
> > > - clk_prepare_enable(priv->pclk);
> > > - clk_prepare_enable(priv->osc_clk);
> > > -
> > > if (priv->devtype == WDT_RZG2L) {
> > > + clk_prepare_enable(priv->pclk);
> > > + clk_prepare_enable(priv->osc_clk);
> > > +
> > > /* Generate Reset (WDTRSTB) Signal on parity error */
> > > rzg2l_wdt_write(priv, 0, PECR);
> > >
> > > @@ -157,6 +157,11 @@ static int rzg2l_wdt_restart(struct watchdog_device
> > *wdev,
> > > } else {
> > > /* RZ/V2M doesn't have parity error registers */
> > >
> > > + reset_control_reset(priv->rstc);
> > > +
> > > + clk_prepare_enable(priv->pclk);
> > > + clk_prepare_enable(priv->osc_clk);
> > > +
> > > wdev->timeout = 0;
> > >
> > > /* Initialize time out */
> > > --
> > > 2.34.1
> > >