• Lv Zheng's avatar
    ACPICA: Hardware: Enable firmware waking vector for both 32-bit and 64-bit FACS · f06147f9
    Lv Zheng authored
    ACPICA commit 368eb60778b27b6ae94d3658ddc902ca1342a963
    ACPICA commit 70f62a80d65515e1285fdeeb50d94ee6f07df4bd
    ACPICA commit a04dbfa308a48ab0b2d10519c54a6c533c5c8949
    ACPICA commit ebd544ed24c5a4faba11f265e228b7a821a729f5
    
    The following commit is reported to have broken s2ram on some platforms:
     Commit: 0249ed24
     ACPICA: Add option to favor 32-bit FADT addresses.
    The platform reports 2 FACS tables (which is not allowed by ACPI
    specification) and the new 32-bit address favor rule forces OSPMs to use
    the FACS table reported via FADT's X_FIRMWARE_CTRL field.
    
    The root cause of the reported bug might be one of the followings:
    1. BIOS may favor the 64-bit firmware waking vector address when the
       version of the FACS is greater than 0 and Linux currently only supports
       resuming from the real mode, so the 64-bit firmware waking vector has
       never been set and might be invalid to BIOS while the commit enables
       higher version FACS.
    2. BIOS may favor the FACS reported via the "FIRMWARE_CTRL" field in the
       FADT while the commit doesn't set the firmware waking vector address of
       the FACS reported by "FIRMWARE_CTRL", it only sets the firware waking
       vector address of the FACS reported by "X_FIRMWARE_CTRL".
    
    This patch excludes the cases that can trigger the bugs caused by the root
    cause 2.
    
    There is no handshaking mechanism can be used by OSPM to tell BIOS which
    FACS is currently used. Thus the FACS reported by "FIRMWARE_CTRL" may still
    be used by BIOS and the 0 value of the 32-bit firmware waking vector might
    trigger such failure.
    
    This patch enables the firmware waking vectors for both 32bit/64bit FACS
    tables in order to ensure we can exclude the cases that trigger the bugs
    caused by the root cause 2. The exclusion is split into 2 commits so that
    if it turns out not to be necessary, this single commit can be reverted
    without affecting the useful one. Lv Zheng, Bob Moore.
    
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=74021
    Link: https://github.com/acpica/acpica/commit/368eb607
    Link: https://github.com/acpica/acpica/commit/70f62a80
    Link: https://github.com/acpica/acpica/commit/a04dbfa3
    Link: https://github.com/acpica/acpica/commit/ebd544edReported-and-tested-by: default avatarOswald Buddenhagen <ossi@kde.org>
    Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
    Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    f06147f9
acglobal.h 14 KB