Updated to 4.16.12.a

1 files changed, 117 insertions, 0 deletions

diff --git a/ACPI-watchdog-Prefer-iTCO_wdt-on-Lenovo-Z50-70.patch b/ACPI-watchdog-Prefer-iTCO_wdt-on-Lenovo-Z50-70.patch
new file mode 100644
index 0000000..1855da1
--- /dev/null
+++ b/ACPI-watchdog-Prefer-iTCO_wdt-on-Lenovo-Z50-70.patch
@@ -0,0 +1,117 @@
+From a0a37862a4e1844793d39aca9ccb8fecbdcb8659 Mon Sep 17 00:00:00 2001
+From: Mika Westerberg <mika.westerberg@linux.intel.com>
+Date: Mon, 23 Apr 2018 14:16:03 +0300
+Subject: [PATCH] ACPI / watchdog: Prefer iTCO_wdt on Lenovo Z50-70
+
+WDAT table on Lenovo Z50-70 is using RTC SRAM (ports 0x70 and 0x71) to
+store state of the timer. This conflicts with Linux RTC driver
+(rtc-cmos.c) who fails to reserve those ports for itself preventing RTC
+from functioning. In addition the WDAT table seems not to be fully
+functional because it does not reset the system when the watchdog times
+out.
+
+On this system iTCO_wdt works just fine so we simply prefer to use it
+instead of WDAT. This makes RTC working again and also results working
+watchdog via iTCO_wdt.
+
+Reported-by: Peter Milley <pbmilley@gmail.com>
+Link: https://bugzilla.kernel.org/show_bug.cgi?id=199033
+Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
+Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+---
+ drivers/acpi/acpi_watchdog.c | 59 ++++++++++++++++++++++++++++++------
+ 1 file changed, 49 insertions(+), 10 deletions(-)
+
+diff --git a/drivers/acpi/acpi_watchdog.c b/drivers/acpi/acpi_watchdog.c
+index ebb626ffb5fa..4bde16fb97d8 100644
+--- a/drivers/acpi/acpi_watchdog.c
++++ b/drivers/acpi/acpi_watchdog.c
+@@ -12,23 +12,64 @@
+ #define pr_fmt(fmt) "ACPI: watchdog: " fmt
+ 
+ #include <linux/acpi.h>
++#include <linux/dmi.h>
+ #include <linux/ioport.h>
+ #include <linux/platform_device.h>
+ 
+ #include "internal.h"
+ 
++static const struct dmi_system_id acpi_watchdog_skip[] = {
++	{
++		/*
++		 * On Lenovo Z50-70 there are two issues with the WDAT
++		 * table. First some of the instructions use RTC SRAM
++		 * to store persistent information. This does not work well
++		 * with Linux RTC driver. Second, more important thing is
++		 * that the instructions do not actually reset the system.
++		 *
++		 * On this particular system iTCO_wdt seems to work just
++		 * fine so we prefer that over WDAT for now.
++		 *
++		 * See also https://bugzilla.kernel.org/show_bug.cgi?id=199033.
++		 */
++		.ident = "Lenovo Z50-70",
++		.matches = {
++			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
++			DMI_MATCH(DMI_PRODUCT_NAME, "20354"),
++			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo Z50-70"),
++		},
++	},
++	{}
++};
++
++static const struct acpi_table_wdat *acpi_watchdog_get_wdat(void)
++{
++	const struct acpi_table_wdat *wdat = NULL;
++	acpi_status status;
++
++	if (acpi_disabled)
++		return NULL;
++
++	if (dmi_check_system(acpi_watchdog_skip))
++		return NULL;
++
++	status = acpi_get_table(ACPI_SIG_WDAT, 0,
++				(struct acpi_table_header **)&wdat);
++	if (ACPI_FAILURE(status)) {
++		/* It is fine if there is no WDAT */
++		return NULL;
++	}
++
++	return wdat;
++}
++
+ /**
+  * Returns true if this system should prefer ACPI based watchdog instead of
+  * the native one (which are typically the same hardware).
+  */
+ bool acpi_has_watchdog(void)
+ {
+-	struct acpi_table_header hdr;
+-
+-	if (acpi_disabled)
+-		return false;
+-
+-	return ACPI_SUCCESS(acpi_get_table_header(ACPI_SIG_WDAT, 0, &hdr));
++	return !!acpi_watchdog_get_wdat();
+ }
+ EXPORT_SYMBOL_GPL(acpi_has_watchdog);
+ 
+@@ -41,12 +82,10 @@ void __init acpi_watchdog_init(void)
+ 	struct platform_device *pdev;
+ 	struct resource *resources;
+ 	size_t nresources = 0;
+-	acpi_status status;
+ 	int i;
+ 
+-	status = acpi_get_table(ACPI_SIG_WDAT, 0,
+-				(struct acpi_table_header **)&wdat);
+-	if (ACPI_FAILURE(status)) {
++	wdat = acpi_watchdog_get_wdat();
++	if (!wdat) {
+ 		/* It is fine if there is no WDAT */
+ 		return;
+ 	}
+-- 
+2.17.0
+