On Mon, Sep 17, 2018 at 06:22:50AM +0000, Christophe Leroy wrote: > mpc8xxx watchdog driver supports the following platforms: > - mpc8xx > - mpc83xx > - mpc86xx > > Those three platforms have a 32 bits register which provides the > reason of the last boot, including whether it was caused by the > watchdog. > > mpc8xx: Register RSR, bit SWRS (bit 3) > mpc83xx: Register RSR, bit SWRS (bit 28) > mpc86xx: Register RSTRSCR, bit WDT_RR (bit 11) > > This patch maps the register as defined in the device tree and updates > wdt.bootstatus based on the value of the watchdog related bit. Then > the information can be retrieved via the WDIOC_GETBOOTSTATUS ioctl. > > Hereunder is an example of devicetree for mpc8xx, > the Reset Status Register being at offset 0x288: > > WDT: watchdog@0 { > compatible = "fsl,mpc823-wdt"; > reg = <0x0 0x10 0x288 0x4>; > }; > > On the mpc83xx, RSR is at offset 0x910 > On the mpc86xx, RSTRSCR is at offset 0xe0094 > > Suggested-by: Radu Rendec <radu.rendec@xxxxxxxxx> > Tested-by: Christophe Leroy <christophe.leroy@xxxxxx> # On mpc885 > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx> > --- I am ok with the patch, though I would really appreciate change logs in the future. Consider this an informal Reviewed-by:. Waiting for DT review before final approval. Guenter > drivers/watchdog/mpc8xxx_wdt.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/watchdog/mpc8xxx_wdt.c b/drivers/watchdog/mpc8xxx_wdt.c > index 1dcf5f10cdd9..069072e6747d 100644 > --- a/drivers/watchdog/mpc8xxx_wdt.c > +++ b/drivers/watchdog/mpc8xxx_wdt.c > @@ -47,6 +47,7 @@ struct mpc8xxx_wdt { > struct mpc8xxx_wdt_type { > int prescaler; > bool hw_enabled; > + u32 rsr_mask; > }; > > struct mpc8xxx_wdt_ddata { > @@ -159,6 +160,24 @@ static int mpc8xxx_wdt_probe(struct platform_device *ofdev) > return -ENODEV; > } > > + res = platform_get_resource(ofdev, IORESOURCE_MEM, 1); > + if (res) { > + bool status; > + u32 __iomem *rsr = ioremap(res->start, resource_size(res)); > + > + if (!rsr) > + return -ENOMEM; > + > + status = in_be32(rsr) & wdt_type->rsr_mask; > + ddata->wdd.bootstatus = status ? WDIOF_CARDRESET : 0; > + /* clear reset status bits related to watchdog timer */ > + out_be32(rsr, wdt_type->rsr_mask); > + iounmap(rsr); > + > + dev_info(dev, "Last boot was %scaused by watchdog\n", > + status ? "" : "not "); > + } > + > spin_lock_init(&ddata->lock); > > ddata->wdd.info = &mpc8xxx_wdt_info, > @@ -216,6 +235,7 @@ static const struct of_device_id mpc8xxx_wdt_match[] = { > .compatible = "mpc83xx_wdt", > .data = &(struct mpc8xxx_wdt_type) { > .prescaler = 0x10000, > + .rsr_mask = BIT(3), /* RSR Bit SWRS */ > }, > }, > { > @@ -223,6 +243,7 @@ static const struct of_device_id mpc8xxx_wdt_match[] = { > .data = &(struct mpc8xxx_wdt_type) { > .prescaler = 0x10000, > .hw_enabled = true, > + .rsr_mask = BIT(20), /* RSTRSCR Bit WDT_RR */ > }, > }, > { > @@ -230,6 +251,7 @@ static const struct of_device_id mpc8xxx_wdt_match[] = { > .data = &(struct mpc8xxx_wdt_type) { > .prescaler = 0x800, > .hw_enabled = true, > + .rsr_mask = BIT(28), /* RSR Bit SWRS */ > }, > }, > {}, > -- > 2.13.3 >