From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH]ACPI: workaround for S3 fail in two
	facs tables case
Date: Thu, 25 Feb 2010 13:17:17 +0000
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	<C7AC1662.B5A7%keir.fraser@eu.citrix.com>
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>>> Keir Fraser <keir.fraser@eu.citrix.com> 25.02.10 12:58 >>>
>What do you think? And I was looking at Linux 2.6.27 -- has behaviour =
there
>chanegd since then?

Not much, but it got improved - 2.6.33 has

	/*
	 * Expand the 32-bit FACS and DSDT addresses to 64-bit as =
necessary.
	 * Later code will always use the X 64-bit field. Also, check for =
an
	 * address mismatch between the 32-bit and 64-bit address fields
	 * (FIRMWARE_CTRL/X_FIRMWARE_CTRL, DSDT/X_DSDT) which would =
indicate
	 * the presence of two FACS or two DSDT tables.
	 */
	if (!acpi_gbl_FADT.Xfacs) {
		acpi_gbl_FADT.Xfacs =3D (u64) acpi_gbl_FADT.facs;
	} else if (acpi_gbl_FADT.facs &&
		   (acpi_gbl_FADT.Xfacs !=3D (u64) acpi_gbl_FADT.facs)) {
		ACPI_WARNING((AE_INFO,
		    "32/64 FACS address mismatch in FADT - two FACS =
tables!"));
	}

and

	/*
	 * Check for FACS and DSDT address mismatches. An address mismatch =
between
	 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_C=
TRL and
	 * DSDT/X_DSDT) would indicate the presence of two FACS or two =
DSDT tables.
	 */
	if (acpi_gbl_FADT.facs &&
	    (acpi_gbl_FADT.Xfacs !=3D (u64) acpi_gbl_FADT.facs)) {
		ACPI_WARNING((AE_INFO,
			      "32/64X FACS address mismatch in FADT - "
			      "%8.8X/%8.8X%8.8X, using 32",
			      acpi_gbl_FADT.facs,
			      ACPI_FORMAT_UINT64(acpi_gbl_FADT.Xfacs)));

		acpi_gbl_FADT.Xfacs =3D (u64) acpi_gbl_FADT.facs;
	}

(and as the comments say, each repeated for the DSDT).

Jan