[PATCH v7 0/3] Xen/ACPI: support sleep state entering on hardware reduced systems

[PATCH v7 0/3] Xen/ACPI: support sleep state entering on hardware reduced systems

[Ben Guthro]

In version 3.4 acpi_os_prepare_sleep() got introduced in parallel with
reduced hardware sleep support, and the two changes didn't get
synchronized: The new code doesn't call the hook function (if so
requested). Fix this, requiring a new callback to be added to acpica
to be called back during this reduced hardware sleep.

This requires adjusting TXT, but the adjustments only go as far as
failing the extended mode call (since, looking at the TXT interface,
there doesn't even appear to be precautions to deal with that
alternative interface).

The xen hypervisor change underlying this is commit 62d1a69 ("ACPI: support
v5 (reduced HW) sleep interface") on the master branch of
git://xenbits.xen.org/xen.git.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
Cc: Richard L Maliszewski <richard.l.maliszewski@intel.com>
Cc: Gang Wei <gang.wei@intel.com>
Cc: Shane Wang <shane.wang@intel.com>
Cc: Bob Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: linux-acpi@vger.kernel.org
Cc: tboot-devel@lists.sourceforge.net 

v2: Extend description to include reference to hypervisor side change
v3: Split into multiple patches, separating subsystems
    Remove bool parameters, in favor of u8
v4: Remove linux/acpi.h dependencies
    Further patch split to break out acpica from OSL
    More bool vs u8 fixes
v5: Fix build of consumers of acpi_os_prepare_sleep() interface change,
    so intermediate builds of partial patch series will not fail.
v6: Rebased to linux-pm linux-next branch
    Added warning in tboot early return code
    Added Reviewed-by lines
v7: Add separate acpi_os_prepare_extended_sleep() interface
    Remove OSL acpica changes introduced in v4

Ben Guthro (3):
  x86/acpi: Introduce acpi_os_prepare_extended_sleep callback for
    extended sleep path
  x86/tboot: Fail extended mode reduced hardware sleep
  xen/acpi: notify xen when reduced hardware sleep is available

 arch/x86/kernel/tboot.c          |   12 +++++++++++
 drivers/acpi/acpica/hwesleep.c   |    9 +++++++++
 drivers/acpi/osl.c               |   24 ++++++++++++++++++++++
 drivers/xen/acpi.c               |   41 ++++++++++++++++++++++++++------------
 include/linux/acpi.h             |    7 +++++++
 include/xen/acpi.h               |    8 ++++++--
 include/xen/interface/platform.h |    7 ++++---
 7 files changed, 90 insertions(+), 18 deletions(-)

-- 
1.7.9.5

[PATCH v7 1/3] x86/acpi: Introduce acpi_os_prepare_extended_sleep callback for extended sleep path

[Ben Guthro]

Like acpi_os_prepare_sleep, register a callback for use in systems like
tboot, and xen, which have system specific requirements outside of acpica.
This mirrors the functionality in acpi_os_prepare_sleep(), called from
acpi_hw_sleep()

Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
---
 drivers/acpi/acpica/hwesleep.c |    9 +++++++++
 drivers/acpi/osl.c             |   24 ++++++++++++++++++++++++
 include/linux/acpi.h           |    7 +++++++
 3 files changed, 40 insertions(+)

diff --git a/drivers/acpi/acpica/hwesleep.c b/drivers/acpi/acpica/hwesleep.c
index 5e5f762..4140768 100644
--- a/drivers/acpi/acpica/hwesleep.c
+++ b/drivers/acpi/acpica/hwesleep.c
@@ -43,6 +43,7 @@
  */
 
 #include <acpi/acpi.h>
+#include <linux/acpi.h>
 #include "accommon.h"
 
 #define _COMPONENT          ACPI_HARDWARE
@@ -128,6 +129,14 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state)
 
 	ACPI_FLUSH_CPU_CACHE();
 
+	status = acpi_os_prepare_extended_sleep(sleep_state,
+						acpi_gbl_sleep_type_a,
+						acpi_gbl_sleep_type_b);
+	if (ACPI_SKIP(status))
+		return_ACPI_STATUS(AE_OK);
+	if (ACPI_FAILURE(status))
+		return_ACPI_STATUS(status);
+
 	/*
 	 * Set the SLP_TYP and SLP_EN bits.
 	 *
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 6ab2c35..a934950 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -79,6 +79,8 @@ extern char line_buf[80];
 
 static int (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
 				      u32 pm1b_ctrl);
+static int (*__acpi_os_prepare_extended_sleep)(u8 sleep_state, u32 val_a,
+				      u32 val_b);
 
 static acpi_osd_handler acpi_irq_handler;
 static void *acpi_irq_context;
@@ -1779,6 +1781,28 @@ void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
 	__acpi_os_prepare_sleep = func;
 }
 
+acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state, u32 val_a,
+				  u32 val_b)
+{
+	int rc = 0;
+	if (__acpi_os_prepare_extended_sleep)
+		rc = __acpi_os_prepare_extended_sleep(sleep_state,
+					     val_a, val_b);
+	if (rc < 0)
+		return AE_ERROR;
+	else if (rc > 0)
+		return AE_CTRL_SKIP;
+
+	return AE_OK;
+}
+
+void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
+			       u32 val_a, u32 val_b))
+{
+	__acpi_os_prepare_extended_sleep = func;
+}
+
+
 void alloc_acpi_hp_work(acpi_handle handle, u32 type, void *context,
 			void (*func)(struct work_struct *work))
 {
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 353ba25..a5db4ae 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -481,6 +481,13 @@ void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
 
 acpi_status acpi_os_prepare_sleep(u8 sleep_state,
 				  u32 pm1a_control, u32 pm1b_control);
+
+void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
+				        u32 val_a,  u32 val_b));
+
+acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state,
+					   u32 val_a, u32 val_b);
+
 #ifdef CONFIG_X86
 void arch_reserve_mem_area(acpi_physical_address addr, size_t size);
 #else
-- 
1.7.9.5

[PATCH v7 2/3] x86/tboot: Fail extended mode reduced hardware sleep

[Ben Guthro]

Register for the extended sleep callback from acpi.
As tboot currently does not support the reduced hardware sleep
interface, fail this extended call.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
Cc: tboot-devel@lists.sourceforge.net
Cc: Gang Wei <gang.wei@intel.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 arch/x86/kernel/tboot.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index addf7b5..760f431 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -301,6 +301,17 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
 	return 0;
 }
 
+static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
+{
+	if (!tboot_enabled())
+		return 0;
+
+	pr_warning("tboot is not able to suspend on platforms with"
+		   " reduced hardware sleep (ACPIv5). Please contact"
+		   " tboot-devel@lists.sourceforge.net mailing list.");
+	return -1;
+}
+
 static atomic_t ap_wfs_count;
 
 static int tboot_wait_for_aps(int num_aps)
@@ -422,6 +433,7 @@ static __init int tboot_late_init(void)
 #endif
 
 	acpi_os_set_prepare_sleep(&tboot_sleep);
+	acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep);
 	return 0;
 }
 
-- 
1.7.9.5

Re: [PATCH v7 2/3] x86/tboot: Fail extended mode reduced hardware sleep

[Rafael J. Wysocki]

On Monday, July 29, 2013 01:14:14 PM Ben Guthro wrote:
> Register for the extended sleep callback from acpi.
> As tboot currently does not support the reduced hardware sleep
> interface, fail this extended call.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
> Cc: tboot-devel@lists.sourceforge.net
> Cc: Gang Wei <gang.wei@intel.com>
> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
>  arch/x86/kernel/tboot.c |   12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
> index addf7b5..760f431 100644
> --- a/arch/x86/kernel/tboot.c
> +++ b/arch/x86/kernel/tboot.c
> @@ -301,6 +301,17 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
>  	return 0;
>  }
>  
> +static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
> +{
> +	if (!tboot_enabled())
> +		return 0;
> +
> +	pr_warning("tboot is not able to suspend on platforms with"
> +		   " reduced hardware sleep (ACPIv5). Please contact"
> +		   " tboot-devel@lists.sourceforge.net mailing list.");
> +	return -1;

Please use a meaningful error code here.  For example -ENODEV.

> +}
> +
>  static atomic_t ap_wfs_count;
>  
>  static int tboot_wait_for_aps(int num_aps)
> @@ -422,6 +433,7 @@ static __init int tboot_late_init(void)
>  #endif
>  
>  	acpi_os_set_prepare_sleep(&tboot_sleep);
> +	acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep);
>  	return 0;
>  }

Thanks,
Rafael


-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH v7 2/3] x86/tboot: Fail extended mode reduced hardware sleep

[Ben Guthro]

On 07/29/2013 04:21 PM, Rafael J. Wysocki wrote:
> On Monday, July 29, 2013 01:14:14 PM Ben Guthro wrote:
>> Register for the extended sleep callback from acpi.
>> As tboot currently does not support the reduced hardware sleep
>> interface, fail this extended call.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
>> Cc: tboot-devel@lists.sourceforge.net
>> Cc: Gang Wei <gang.wei@intel.com>
>> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>> ---
>>  arch/x86/kernel/tboot.c |   12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
>> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
>> index addf7b5..760f431 100644
>> --- a/arch/x86/kernel/tboot.c
>> +++ b/arch/x86/kernel/tboot.c
>> @@ -301,6 +301,17 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
>>  	return 0;
>>  }
>>  
>> +static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
>> +{
>> +	if (!tboot_enabled())
>> +		return 0;
>> +
>> +	pr_warning("tboot is not able to suspend on platforms with"
>> +		   " reduced hardware sleep (ACPIv5). Please contact"
>> +		   " tboot-devel@lists.sourceforge.net mailing list.");
>> +	return -1;
> 
> Please use a meaningful error code here.  For example -ENODEV.

Would AE_NOT_IMPLEMENTED be more appropriate?

include/acpi/acexcep.h:
#define AE_NOT_IMPLEMENTED              EXCEP_ENV (0x000E)




> 
>> +}
>> +
>>  static atomic_t ap_wfs_count;
>>  
>>  static int tboot_wait_for_aps(int num_aps)
>> @@ -422,6 +433,7 @@ static __init int tboot_late_init(void)
>>  #endif
>>  
>>  	acpi_os_set_prepare_sleep(&tboot_sleep);
>> +	acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep);
>>  	return 0;
>>  }
> 
> Thanks,
> Rafael
> 
> 

Re: [PATCH v7 2/3] x86/tboot: Fail extended mode reduced hardware sleep

[Rafael J. Wysocki]

On Monday, July 29, 2013 04:18:22 PM Ben Guthro wrote:
> 
> On 07/29/2013 04:21 PM, Rafael J. Wysocki wrote:
> > On Monday, July 29, 2013 01:14:14 PM Ben Guthro wrote:
> >> Register for the extended sleep callback from acpi.
> >> As tboot currently does not support the reduced hardware sleep
> >> interface, fail this extended call.
> >>
> >> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> >> Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
> >> Cc: tboot-devel@lists.sourceforge.net
> >> Cc: Gang Wei <gang.wei@intel.com>
> >> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> >> ---
> >>  arch/x86/kernel/tboot.c |   12 ++++++++++++
> >>  1 file changed, 12 insertions(+)
> >>
> >> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
> >> index addf7b5..760f431 100644
> >> --- a/arch/x86/kernel/tboot.c
> >> +++ b/arch/x86/kernel/tboot.c
> >> @@ -301,6 +301,17 @@ static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
> >>  	return 0;
> >>  }
> >>  
> >> +static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
> >> +{
> >> +	if (!tboot_enabled())
> >> +		return 0;
> >> +
> >> +	pr_warning("tboot is not able to suspend on platforms with"
> >> +		   " reduced hardware sleep (ACPIv5). Please contact"
> >> +		   " tboot-devel@lists.sourceforge.net mailing list.");
> >> +	return -1;
> > 
> > Please use a meaningful error code here.  For example -ENODEV.
> 
> Would AE_NOT_IMPLEMENTED be more appropriate?
> 
> include/acpi/acexcep.h:
> #define AE_NOT_IMPLEMENTED              EXCEP_ENV (0x000E)

This is not an ACPI error. :-)

Rafael

[PATCH v7 3/3] xen/acpi: notify xen when reduced hardware sleep is available

[Ben Guthro]

Make use of acpi_os_prepare_extended_sleep callback to notify xen
to make use of the reduced hardware sleep functionality

The xen hypervisor change underlying this is commit 62d1a69
("ACPI: support v5 (reduced HW) sleep interface") on the master
branch of git://xenbits.xen.org/xen.git.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Ben Guthro <benjamin.guthro@citrix.com>
Acked-by: Konrad Wilk <konrad.wilk@oracle.com>
---
 drivers/xen/acpi.c               |   41 ++++++++++++++++++++++++++------------
 include/xen/acpi.h               |    8 ++++++--
 include/xen/interface/platform.h |    7 ++++---
 3 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/drivers/xen/acpi.c b/drivers/xen/acpi.c
index 119d42a..90307c0 100644
--- a/drivers/xen/acpi.c
+++ b/drivers/xen/acpi.c
@@ -35,28 +35,43 @@
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
 
-int xen_acpi_notify_hypervisor_state(u8 sleep_state,
-				     u32 pm1a_cnt, u32 pm1b_cnt)
+static int xen_acpi_notify_hypervisor_state(u8 sleep_state,
+					    u32 val_a, u32 val_b,
+					    bool extended)
 {
+	unsigned int bits = extended ? 8 : 16;
+
 	struct xen_platform_op op = {
 		.cmd = XENPF_enter_acpi_sleep,
 		.interface_version = XENPF_INTERFACE_VERSION,
-		.u = {
-			.enter_acpi_sleep = {
-				.pm1a_cnt_val = (u16)pm1a_cnt,
-				.pm1b_cnt_val = (u16)pm1b_cnt,
-				.sleep_state = sleep_state,
-			},
+		.u.enter_acpi_sleep = {
+			.val_a = (u16)val_a,
+			.val_b = (u16)val_b,
+			.sleep_state = sleep_state,
+			.flags = extended ? XENPF_ACPI_SLEEP_EXTENDED : 0,
 		},
 	};
 
-	if ((pm1a_cnt & 0xffff0000) || (pm1b_cnt & 0xffff0000)) {
-		WARN(1, "Using more than 16bits of PM1A/B 0x%x/0x%x!"
-		     "Email xen-devel@lists.xensource.com  Thank you.\n", \
-		     pm1a_cnt, pm1b_cnt);
+	if (WARN((val_a & (~0 << bits)) || (val_b & (~0 << bits)),
+		 "Using more than %u bits of sleep control values %#x/%#x!"
+		 "Email xen-devel@lists.xen.org - Thank you.\n", \
+		 bits, val_a, val_b))
 		return -1;
-	}
 
 	HYPERVISOR_dom0_op(&op);
 	return 1;
 }
+
+int xen_acpi_notify_hypervisor_sleep(u8 sleep_state,
+				     u32 pm1a_cnt, u32 pm1b_cnt)
+{
+	return xen_acpi_notify_hypervisor_state(sleep_state, pm1a_cnt,
+						pm1b_cnt, false);
+}
+
+int xen_acpi_notify_hypervisor_extended_sleep(u8 sleep_state,
+				     u32 val_a, u32 val_b)
+{
+	return xen_acpi_notify_hypervisor_state(sleep_state, val_a,
+						val_b, true);
+}
diff --git a/include/xen/acpi.h b/include/xen/acpi.h
index 46aa3d1..4ddd7dc 100644
--- a/include/xen/acpi.h
+++ b/include/xen/acpi.h
@@ -75,8 +75,10 @@ static inline int xen_acpi_get_pxm(acpi_handle h)
 	return -ENXIO;
 }
 
-int xen_acpi_notify_hypervisor_state(u8 sleep_state,
+int xen_acpi_notify_hypervisor_sleep(u8 sleep_state,
 				     u32 pm1a_cnt, u32 pm1b_cnd);
+int xen_acpi_notify_hypervisor_extended_sleep(u8 sleep_state,
+				     u32 val_a, u32 val_b);
 
 static inline int xen_acpi_suspend_lowlevel(void)
 {
@@ -93,7 +95,9 @@ static inline void xen_acpi_sleep_register(void)
 {
 	if (xen_initial_domain()) {
 		acpi_os_set_prepare_sleep(
-			&xen_acpi_notify_hypervisor_state);
+			&xen_acpi_notify_hypervisor_sleep);
+		acpi_os_set_prepare_extended_sleep(
+			&xen_acpi_notify_hypervisor_extended_sleep);
 
 		acpi_suspend_lowlevel = xen_acpi_suspend_lowlevel;
 	}
diff --git a/include/xen/interface/platform.h b/include/xen/interface/platform.h
index c57d5f6..f1331e3 100644
--- a/include/xen/interface/platform.h
+++ b/include/xen/interface/platform.h
@@ -152,10 +152,11 @@ DEFINE_GUEST_HANDLE_STRUCT(xenpf_firmware_info_t);
 #define XENPF_enter_acpi_sleep    51
 struct xenpf_enter_acpi_sleep {
 	/* IN variables */
-	uint16_t pm1a_cnt_val;      /* PM1a control value. */
-	uint16_t pm1b_cnt_val;      /* PM1b control value. */
+	uint16_t val_a;             /* PM1a control / sleep type A. */
+	uint16_t val_b;             /* PM1b control / sleep type B. */
 	uint32_t sleep_state;       /* Which state to enter (Sn). */
-	uint32_t flags;             /* Must be zero. */
+#define XENPF_ACPI_SLEEP_EXTENDED 0x00000001
+	uint32_t flags;             /* XENPF_ACPI_SLEEP_*. */
 };
 DEFINE_GUEST_HANDLE_STRUCT(xenpf_enter_acpi_sleep_t);
 
-- 
1.7.9.5