Commit 82627037 authored by Terry Bowman's avatar Terry Bowman Committed by Wim Van Sebroeck
Browse files

Watchdog: sp5100_tco: Enable Family 17h+ CPUs 



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: default avatarRobert Richter <rrichter@amd.com>
Signed-off-by: default avatarRobert Richter <rrichter@amd.com>
Signed-off-by: default avatarTerry Bowman <terry.bowman@amd.com>
Tested-by: default avatarJean Delvare <jdelvare@suse.de>
Reviewed-by: default avatarJean Delvare <jdelvare@suse.de>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220202153525.1693378-5-terry.bowman@amd.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarWim Van Sebroeck <wim@linux-watchdog.org>
parent 0578fff4

drivers/watchdog/sp5100_tco.c

+4 −12
Original line number Diff line number Diff line
@@ -86,6 +86,10 @@ static enum tco_reg_layout tco_reg_layout(struct pci_dev *dev) 
	    dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&

	    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) ||
@@ -459,18 +463,6 @@ 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;

drivers/watchdog/sp5100_tco.h

+1 −0
Original line number Diff line number Diff line
@@ -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