Hi Jan, On 9/10/20 9:34 AM, Jan Kiszka wrote: > 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 <[email protected]> >> Signed-off-by: Guenter Roeck <[email protected]> >> --- >> 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. >
Yes, it does use EFCH_PM_WDT_ADDR. EFCH_PM_ACPI_MMIO_ADDR works as well, but is meant to be a fallback. Both point to the watchdog memory space. Thanks, Guenter
