On 10.09.20 18:31, Guenter Roeck wrote:
> On Family 17h (Ryzen) devices, the WatchdogTmrEn bit of PmDecodeEn not only
> enables watchdog memory decoding at 0xfeb00000, it also enables the
> watchdog hardware itself. Use this information to enable the watchdog if
> it is not already enabled.
>
> Cc: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> drivers/watchdog/sp5100_tco.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
> index 85e9664318c9..a730ecbf78cd 100644
> --- a/drivers/watchdog/sp5100_tco.c
> +++ b/drivers/watchdog/sp5100_tco.c
> @@ -17,6 +17,12 @@
> * AMD Publication 51192 "AMD Bolton FCH Register Reference Guide"
> * AMD Publication 52740 "BIOS and Kernel Developer’s Guide (BKDG)
> * for AMD Family 16h Models 30h-3Fh Processors"
> + * AMD Publication 55570-B1-PUB "Processor Programming Reference (PPR)
> + * for AMD Family 17h Model 18h, Revision B1
> + * Processors (PUB)
> + * AMD Publication 55772-A1-PUB "Processor Programming Reference (PPR)
> + * for AMD Family 17h Model 20h, Revision A1
> + * Processors (PUB)
> */
>
> /*
> @@ -241,6 +247,18 @@ static int sp5100_tco_setupdevice(struct device *dev,
> break;
> case efch:
> dev_name = SB800_DEVNAME;
> + /*
> + * On Family 17h devices, the EFCH_PM_DECODEEN_WDT_TMREN bit of
> + * EFCH_PM_DECODEEN not only enables the EFCH_PM_WDT_ADDR memory
> + * region, it also enables the watchdog itself.
> + */
> + if (boot_cpu_data.x86 == 0x17) {
> + val = sp5100_tco_read_pm_reg8(EFCH_PM_DECODEEN);
> + if (!(val & EFCH_PM_DECODEEN_WDT_TMREN)) {
> + sp5100_tco_update_pm_reg8(EFCH_PM_DECODEEN, 0xff,
> + EFCH_PM_DECODEEN_WDT_TMREN);
> + }
> + }
> val = sp5100_tco_read_pm_reg8(EFCH_PM_DECODEEN);
> if (val & EFCH_PM_DECODEEN_WDT_TMREN)
> mmio_addr = EFCH_PM_WDT_ADDR;
>
Won't that bring us EFCH_PM_WDT_ADDR as address, rather than
EFCH_PM_ACPI_MMIO_ADDR which worked in my case? Or is one an alias of
the other.
Jan
--
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux
