Re: [PATCH] ACPI suspend: Always use the 32-bit waking vector

[Pavel Machek <pavel@suse.cz>]

Hi!

> Well, I read this part of the spec (2.0c, 3.0b) more carefully and it matches
> what you're saying.  Moreover, my understanding of it is that we should
> actually _clear_ the 64-bit vector on systems that support it, because
> otherwise the BIOS is supposed to use it and call the wake-up code in protected
> mode.
> 
> The appended patch is based on this observation.
> 
> Thanks,
> Rafael
> 
> ---
> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> ACPI suspend: Always use the 32-bit waking vector
> 
> According to the ACPI specification 2.0c and later, the 64-bit waking vector
> should be cleared and the 32-bit waking vector should be used, unless we want
> the wake-up code to be called by the BIOS in Protected Mode.  Moreover, some
> systems (for example HP dv5-1004nr) are known to fail to resume if the 64-bit
> waking vector is used.  Therefore, modify the code to clear the 64-bit waking
> vector, for FACS version 1 or greater, and set the 32-bit one before suspend.
> 
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> ---
>  drivers/acpi/hardware/hwsleep.c |   37 +++++++++++--------------------------
>  1 file changed, 11 insertions(+), 26 deletions(-)
> 
> @@ -134,20 +132,7 @@ acpi_get_firmware_waking_vector(acpi_phy
>  	}
>  
>  	/* Get the vector */
> -
> -	if ((facs->length < 32) || (!(facs->xfirmware_waking_vector))) {
> -		/*
> -		 * ACPI 1.0 FACS or short table or optional X_ field is zero
> -		 */
> -		*physical_address =
> -		    (acpi_physical_address) facs->firmware_waking_vector;
> -	} else {
> -		/*
> -		 * ACPI 2.0 FACS with valid X_ field
> -		 */
> -		*physical_address =
> -		    (acpi_physical_address) facs->xfirmware_waking_vector;
> -	}
> +	*physical_address = (acpi_physical_address)facs->firmware_waking_vector;
>  
>  	return_ACPI_STATUS(AE_OK);
>  }

Actually, I guess we should kill acpi_get_firmware_waking_vector: It
is completely useless, and it is indeed never used in whole Linux...
								Pavel
-- 
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