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

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

On Fri, Dec 16, 2011 at 05:38:13PM -0500, Konrad Rzeszutek Wilk wrote:
> From: Tang Liang <liang.tang@oracle.com>

Hey Joseph,

I remember you acked the initial rfc patches I had posted.
But I was wondering if these ones are to your liking (I think they are -
they aren't that much different, but I didn't want to blindly sticking
'Acked-by' as they did change a bit).

Thanks!
> 
> 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.
> 
> CC: Thomas Gleixner <tglx@linutronix.de>
> CC: "H. Peter Anvin" <hpa@zytor.com>
> CC: x86@kernel.org
> CC: Len Brown <len.brown@intel.com>
> CC: Joseph Cihula <joseph.cihula@intel.com>
> CC: Shane Wang <shane.wang@intel.com>
> CC: xen-devel@lists.xensource.com
> CC: linux-pm@lists.linux-foundation.org
> CC: tboot-devel@lists.sourceforge.net
> CC: linux-acpi@vger.kernel.org
> [v1: Added __attribute__ ((unused))]
> [v2: Introduced a wrapper instead of changing tboot_sleep return values]
> [v3: Added return value AE_CTRL_SKIP for acpi_os_sleep_prepare]
> Signed-off-by: Tang Liang <liang.tang@oracle.com>
> [v1: Fix compile issues on IA64 and PPC64]
> [v2: Fix where __acpi_os_prepare_sleep==NULL and did not go in sleep properly]
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
>  arch/x86/kernel/tboot.c       |    8 ++++++++
>  drivers/acpi/acpica/hwsleep.c |   10 +++++++---
>  drivers/acpi/osl.c            |   24 ++++++++++++++++++++++++
>  include/acpi/acexcep.h        |    1 +
>  include/linux/acpi.h          |   10 ++++++++++
>  include/linux/tboot.h         |    1 -
>  6 files changed, 50 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
> index e2410e2..1a4ab7d 100644
> --- a/arch/x86/kernel/tboot.c
> +++ b/arch/x86/kernel/tboot.c
> @@ -297,6 +297,12 @@ void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
>  
>  	tboot_shutdown(acpi_shutdown_map[sleep_state]);
>  }
> +static int tboot_sleep_wrapper(u8 sleep_state, u32 pm1a_control,
> +			       u32 pm1b_control)
> +{
> +	tboot_sleep(sleep_state, pm1a_control, pm1b_control);
> +	return 0;
> +}
>  
>  static atomic_t ap_wfs_count;
>  
> @@ -345,6 +351,8 @@ static __init int tboot_late_init(void)
>  
>  	atomic_set(&ap_wfs_count, 0);
>  	register_hotcpu_notifier(&tboot_cpu_notifier);
> +
> +	acpi_os_set_prepare_sleep(&tboot_sleep_wrapper);
>  	return 0;
>  }
>  
> diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c
> index d52da30..992359a 100644
> --- a/drivers/acpi/acpica/hwsleep.c
> +++ b/drivers/acpi/acpica/hwsleep.c
> @@ -43,9 +43,9 @@
>   */
>  
>  #include <acpi/acpi.h>
> +#include <linux/acpi.h>
>  #include "accommon.h"
>  #include "actables.h"
> -#include <linux/tboot.h>
>  #include <linux/module.h>
>  
>  #define _COMPONENT          ACPI_HARDWARE
> @@ -344,8 +344,12 @@ 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_SKIP(status))
> +		return_ACPI_STATUS(AE_OK);
> +	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..f3aae4b 100644
> --- a/drivers/acpi/osl.c
> +++ b/drivers/acpi/osl.c
> @@ -76,6 +76,9 @@ EXPORT_SYMBOL(acpi_in_debugger);
>  extern char line_buf[80];
>  #endif				/*ENABLE_DEBUGGER */
>  
> +static int (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
> +				      u32 pm1b_ctrl);
> +
>  static acpi_osd_handler acpi_irq_handler;
>  static void *acpi_irq_context;
>  static struct workqueue_struct *kacpid_wq;
> @@ -1659,3 +1662,24 @@ acpi_status acpi_os_terminate(void)
>  
>  	return AE_OK;
>  }
> +
> +acpi_status acpi_os_prepare_sleep(u8 sleep_state, u32 pm1a_control,
> +				  u32 pm1b_control)
> +{
> +	int rc = 0;
> +	if (__acpi_os_prepare_sleep)
> +		rc = __acpi_os_prepare_sleep(sleep_state,
> +					     pm1a_control, pm1b_control);
> +	if (rc < 0)
> +		return AE_ERROR;
> +	else if (rc > 0)
> +		return AE_CTRL_SKIP;
> +
> +	return AE_OK;
> +}
> +
> +void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
> +			       u32 pm1a_ctrl, u32 pm1b_ctrl))
> +{
> +	__acpi_os_prepare_sleep = func;
> +}
> diff --git a/include/acpi/acexcep.h b/include/acpi/acexcep.h
> index 5b6c391..fa0d22c 100644
> --- a/include/acpi/acexcep.h
> +++ b/include/acpi/acexcep.h
> @@ -57,6 +57,7 @@
>  #define ACPI_SUCCESS(a)                 (!(a))
>  #define ACPI_FAILURE(a)                 (a)
>  
> +#define ACPI_SKIP(a)                    (a == AE_CTRL_SKIP)
>  #define AE_OK                           (acpi_status) 0x0000
>  
>  /*
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 6001b4da..fccd017 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -359,4 +359,14 @@ static inline int suspend_nvs_register(unsigned long a, unsigned long b)
>  }
>  #endif
>  
> +#ifdef CONFIG_ACPI
> +void acpi_os_set_prepare_sleep(int (*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);
> +#else
> +#define acpi_os_set_prepare_sleep(func, pm1a_ctrl, pm1b_ctrl) do { } while (0)
> +#endif
> +
>  #endif	/*_LINUX_ACPI_H*/
> diff --git a/include/linux/tboot.h b/include/linux/tboot.h
> index 1dba6ee..c75128b 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);
> -- 
> 1.7.7.4