From: Terry Bowman <terry.bowman@xxxxxxx> commit 826270373f17fd8ebd10753ca0a5fd2ceb1dc38e upstream. The driver currently uses a CPU family match of 17h to determine EFCH_PM_DECODEEN_WDT_TMREN register support. This family check will not support future AMD CPUs and instead will require driver updates to add support. Remove the family 17h family check and add a check for SMBus PCI revision ID 0x51 or greater. The MMIO access method has been available since at least SMBus controllers using PCI revision 0x51. This revision check will support family 17h and future AMD processors including EFCH functionality without requiring driver changes. Co-developed-by: Robert Richter <rrichter@xxxxxxx> Signed-off-by: Robert Richter <rrichter@xxxxxxx> Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx> Tested-by: Jean Delvare <jdelvare@xxxxxxx> Reviewed-by: Jean Delvare <jdelvare@xxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220202153525.1693378-5-terry.bowman@xxxxxxx Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx> Cc: Mario Limonciello <Mario.Limonciello@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/watchdog/sp5100_tco.c | 16 ++++------------ drivers/watchdog/sp5100_tco.h | 1 + 2 files changed, 5 insertions(+), 12 deletions(-) --- a/drivers/watchdog/sp5100_tco.c +++ b/drivers/watchdog/sp5100_tco.c @@ -87,6 +87,10 @@ static enum tco_reg_layout tco_reg_layou dev->revision < 0x40) { return sp5100; } else if (dev->vendor == PCI_VENDOR_ID_AMD && + sp5100_tco_pci->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS && + sp5100_tco_pci->revision >= AMD_ZEN_SMBUS_PCI_REV) { + return efch_mmio; + } else if (dev->vendor == PCI_VENDOR_ID_AMD && ((dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS && dev->revision >= 0x41) || (dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS && @@ -459,18 +463,6 @@ static int sp5100_tco_setupdevice(struct 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; --- a/drivers/watchdog/sp5100_tco.h +++ b/drivers/watchdog/sp5100_tco.h @@ -89,3 +89,4 @@ #define EFCH_PM_ACPI_MMIO_PM_ADDR (EFCH_PM_ACPI_MMIO_ADDR + \ EFCH_PM_ACPI_MMIO_PM_OFFSET) #define EFCH_PM_ACPI_MMIO_PM_SIZE 8 +#define AMD_ZEN_SMBUS_PCI_REV 0x51