cd6h/cd7h port I/O can be disabled on recent AMD hardware. Read
accesses to disabled cd6h/cd7h port I/O will return F's and written
data is dropped. It is recommended to replace the cd6h/cd7h
port I/O with MMIO.
Co-developed-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Robert Richter <rrichter@xxxxxxx>
Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
To: Guenter Roeck <linux@xxxxxxxxxxxx>
To: linux-watchdog@xxxxxxxxxxxxxxx
To: Jean Delvare <jdelvare@xxxxxxxx>
To: linux-i2c@xxxxxxxxxxxxxxx
To: Wolfram Sang <wsa@xxxxxxxxxx>
To: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
To: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx>
Cc: Robert Richter <rrichter@xxxxxxx>
Cc: Thomas Lendacky <thomas.lendacky@xxxxxxx>
---
drivers/watchdog/sp5100_tco.c | 88 ++++++++++++++++++++++++++++++++++-
drivers/watchdog/sp5100_tco.h | 5 ++
2 files changed, 92 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
index 64ecebd93403..36519a992ca1 100644
--- a/drivers/watchdog/sp5100_tco.c
+++ b/drivers/watchdog/sp5100_tco.c
@@ -49,7 +49,7 @@
/* internal variables */
enum tco_reg_layout {
- sp5100, sb800, efch
+ sp5100, sb800, efch, efch_mmio
};
struct sp5100_tco {
@@ -209,6 +209,8 @@ static void tco_timer_enable(struct sp5100_tco *tco)
~EFCH_PM_WATCHDOG_DISABLE,
EFCH_PM_DECODEEN_SECOND_RES);
break;
+ default:
+ break;
}
}
@@ -318,6 +320,87 @@ static int sp5100_tco_timer_init(struct sp5100_tco *tco)
return 0;
}
+static u8 efch_read_pm_reg8(void __iomem *addr, u8 index)
+{
+ return readb(addr + index);
+}
+
+static void efch_update_pm_reg8(void __iomem *addr, u8 index, u8 reset, u8 set)
+{
+ u8 val;
+
+ val = readb(addr + index);
+ val &= reset;
+ val |= set;
+ writeb(val, addr + index);
+}
+
+static void tco_timer_enable_mmio(void __iomem *addr)
+{
+ efch_update_pm_reg8(addr, EFCH_PM_DECODEEN3,
+ ~EFCH_PM_WATCHDOG_DISABLE,
+ EFCH_PM_DECODEEN_SECOND_RES);
+}
+
+static int sp5100_tco_setupdevice_mmio(struct device *dev,
+ struct watchdog_device *wdd)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+ const char *dev_name = SB800_DEVNAME;
+ u32 mmio_addr = 0, alt_mmio_addr = 0;
+ struct resource *res;
+ void __iomem *addr;
+ int ret;
+
+ res = request_mem_region(EFCH_PM_ACPI_MMIO_PM_ADDR,
+ EFCH_PM_ACPI_MMIO_PM_SIZE,
+ "sp5100_tco");
+
+ if (!res) {
+ dev_err(dev,
+ "SMB base address memory region 0x%x already in use.\n",
+ EFCH_PM_ACPI_MMIO_PM_ADDR);
+ return -EBUSY;
+ }
+
+ addr = ioremap(EFCH_PM_ACPI_MMIO_PM_ADDR,
+ EFCH_PM_ACPI_MMIO_PM_SIZE);
+ if (!addr) {
+ release_resource(res);
+ dev_err(dev, "SMB base address mapping failed.\n");
+ return -ENOMEM;
+ }
+
+ if (!(efch_read_pm_reg8(addr, EFCH_PM_DECODEEN) &
+ EFCH_PM_DECODEEN_WDT_TMREN)) {
+ efch_update_pm_reg8(addr, EFCH_PM_DECODEEN,
+ 0xff,
+ EFCH_PM_DECODEEN_WDT_TMREN);
+ }
+
+ /* Determine MMIO base address */
+ if (efch_read_pm_reg8(addr, EFCH_PM_DECODEEN) &
+ EFCH_PM_DECODEEN_WDT_TMREN)
+ mmio_addr = EFCH_PM_WDT_ADDR;
+
+ /* Determine alternate MMIO base address */
+ if (efch_read_pm_reg8(addr, EFCH_PM_ISACONTROL) &
+ EFCH_PM_ISACONTROL_MMIOEN)
+ alt_mmio_addr = EFCH_PM_ACPI_MMIO_ADDR +
+ EFCH_PM_ACPI_MMIO_WDT_OFFSET;
+
+ ret = sp5100_tco_prepare_base(tco, mmio_addr, alt_mmio_addr, dev_name);
+ if (!ret) {
+ tco_timer_enable_mmio(addr);
+ ret = sp5100_tco_timer_init(tco);
+ }
+
+ iounmap(addr);
+ release_resource(res);
+
+ return ret;
+}
+
static int sp5100_tco_setupdevice(struct device *dev,
struct watchdog_device *wdd)
{
@@ -327,6 +410,9 @@ static int sp5100_tco_setupdevice(struct device *dev,
u32 alt_mmio_addr = 0;
int ret;
+ if (tco->tco_reg_layout == efch_mmio)
+ return sp5100_tco_setupdevice_mmio(dev, wdd);
+
/* Request the IO ports used by this driver */
if (!request_muxed_region(SP5100_IO_PM_INDEX_REG,
SP5100_PM_IOPORTS_SIZE, "sp5100_tco")) {
diff --git a/drivers/watchdog/sp5100_tco.h b/drivers/watchdog/sp5100_tco.h
index adf015aa4126..2df8f8b2c55b 100644
--- a/drivers/watchdog/sp5100_tco.h
+++ b/drivers/watchdog/sp5100_tco.h
@@ -83,3 +83,8 @@
#define EFCH_PM_ACPI_MMIO_ADDR 0xfed80000
#define EFCH_PM_ACPI_MMIO_WDT_OFFSET 0x00000b00
+#define EFCH_PM_ACPI_MMIO_PM_OFFSET 0x00000300
+
+#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
--
2.30.2
