From 09da89abe36a3cb3485ed765ec37ac50227e28b5 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Thu, 10 Sep 2020 09:31:09 -0700 Subject: watchdog: sp5100_tco: Enable watchdog on Family 17h devices if disabled 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 Tested-by: Jan Kiszka Link: https://lore.kernel.org/r/20200910163109.235136-2-linux@roeck-us.net Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/sp5100_tco.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/watchdog') 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; -- cgit 1.4.1