[PATCH 1/7] x86, acpi, tboot: Have a ACPI os prepare sleep instead of calling tboot_sleep.

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

From: Tang Liang <liang.tang@oracle.com>

The ACPI suspend path makes a call to tboot_sleep right before
it writes the PM1A, PM1B values. We replace the direct call to
tboot via an registration callback similar to __acpi_register_gsi.

As part of this, the tboot_sleep need only to register with the
acpi_os_prepare_sleep_register and if it not (on IA64) then it simply
won't be called.

We can also remove the tboot_sleep declerations.

[v1: Added __attribute__ ((unused))]
[v2: Introduced a wrapper instead of changing tboot_sleep return values]
Signed-off-by: Tang Liang <liang.tang@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/kernel/tboot.c       |    9 +++++++++
 drivers/acpi/acpica/hwsleep.c |    7 ++++---
 drivers/acpi/osl.c            |   19 +++++++++++++++++++
 include/acpi/acpiosxf.h       |    6 ++++++
 include/linux/tboot.h         |    3 ---
 5 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index e2410e2..751d673 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -31,6 +31,7 @@
 #include <linux/pfn.h>
 #include <linux/mm.h>
 #include <linux/tboot.h>
+#include <acpi/acpiosxf.h>
 
 #include <asm/trampoline.h>
 #include <asm/processor.h>
@@ -297,6 +298,12 @@ void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
 
 	tboot_shutdown(acpi_shutdown_map[sleep_state]);
 }
+static acpi_status tboot_sleep_wrapper(u8 sleep_state, u32 pm1a_control,
+		u32 pm1b_control)
+{
+	tboot_sleep(sleep_state, pm1a_control, pm1b_control);
+	return AE_OK;
+}
 
 static atomic_t ap_wfs_count;
 
@@ -345,6 +352,8 @@ static __init int tboot_late_init(void)
 
 	atomic_set(&ap_wfs_count, 0);
 	register_hotcpu_notifier(&tboot_cpu_notifier);
+
+	acpi_os_prepare_sleep_register(&tboot_sleep_wrapper);
 	return 0;
 }
 
diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c
index d52da30..b10bc90 100644
--- a/drivers/acpi/acpica/hwsleep.c
+++ b/drivers/acpi/acpica/hwsleep.c
@@ -45,7 +45,6 @@
 #include <acpi/acpi.h>
 #include "accommon.h"
 #include "actables.h"
-#include <linux/tboot.h>
 #include <linux/module.h>
 
 #define _COMPONENT          ACPI_HARDWARE
@@ -344,8 +343,10 @@ acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
 
 	ACPI_FLUSH_CPU_CACHE();
 
-	tboot_sleep(sleep_state, pm1a_control, pm1b_control);
-
+	status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
+				 pm1b_control);
+	if (ACPI_FAILURE(status))
+		return_ACPI_STATUS(status);
 	/* Write #2: Write both SLP_TYP + SLP_EN */
 
 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index f31c5c5..40daa68 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -1659,3 +1659,22 @@ acpi_status acpi_os_terminate(void)
 
 	return AE_OK;
 }
+
+acpi_status (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
+				       u32 pm1b_ctrl);
+
+acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
+		u32 pm1b_control)
+{
+	if (__acpi_os_prepare_sleep)
+		return __acpi_os_prepare_sleep(sleep_state, pm1a_control,
+					       pm1b_control);
+	else
+		return	AE_OK;
+}
+
+void acpi_os_prepare_sleep_register(acpi_status (*func)(u8 sleep_state,
+		 u32 pm1a_ctrl,	u32 pm1b_ctrl))
+{
+	__acpi_os_prepare_sleep = func;
+}
diff --git a/include/acpi/acpiosxf.h b/include/acpi/acpiosxf.h
index 83062ed..ebde1e1 100644
--- a/include/acpi/acpiosxf.h
+++ b/include/acpi/acpiosxf.h
@@ -108,6 +108,12 @@ void acpi_os_delete_lock(acpi_spinlock handle);
 
 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock handle);
 
+void acpi_os_prepare_sleep_register(acpi_status (*func)(u8 sleep_state,
+				    u32 pm1a_ctrl, u32 pm1b_ctrl));
+
+acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
+				  u32 pm1b_control);
+
 void acpi_os_release_lock(acpi_spinlock handle, acpi_cpu_flags flags);
 
 /*
diff --git a/include/linux/tboot.h b/include/linux/tboot.h
index 1dba6ee..d57732d 100644
--- a/include/linux/tboot.h
+++ b/include/linux/tboot.h
@@ -143,7 +143,6 @@ static inline int tboot_enabled(void)
 
 extern void tboot_probe(void);
 extern void tboot_shutdown(u32 shutdown_type);
-extern void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control);
 extern struct acpi_table_header *tboot_get_dmar_table(
 				      struct acpi_table_header *dmar_tbl);
 extern int tboot_force_iommu(void);
@@ -153,8 +152,6 @@ extern int tboot_force_iommu(void);
 #define tboot_enabled()			0
 #define tboot_probe()			do { } while (0)
 #define tboot_shutdown(shutdown_type)	do { } while (0)
-#define tboot_sleep(sleep_state, pm1a_control, pm1b_control)	\
-					do { } while (0)
 #define tboot_get_dmar_table(dmar_tbl)	(dmar_tbl)
 #define tboot_force_iommu()		0
 
-- 
1.7.7.1