From: Shaohua Li Handle FADT 2.0 xpmtmr address 0 case. The patch makes the pmtmr ioport detecting align with ACPICA (the comments are copied from ACPICA code). Signed-off-by: Shaohua Li Cc: "Brown, Len" Signed-off-by: Andrew Morton --- arch/i386/kernel/acpi/boot.c | 7 +++++++ 1 files changed, 7 insertions(+) diff -puN arch/i386/kernel/acpi/boot.c~acpi-handle-fadt-20-xpmtmr-address-0-case arch/i386/kernel/acpi/boot.c --- 25/arch/i386/kernel/acpi/boot.c~acpi-handle-fadt-20-xpmtmr-address-0-case Fri Oct 28 14:59:07 2005 +++ 25-akpm/arch/i386/kernel/acpi/boot.c Fri Oct 28 14:59:07 2005 @@ -641,6 +641,13 @@ static int __init acpi_parse_fadt(unsign return 0; pmtmr_ioport = fadt->xpm_tmr_blk.address; + /* + * "X" fields are optional extensions to the original V1.0 + * fields, so we must selectively expand V1.0 fields if the + * corresponding X field is zero. + */ + if (!pmtmr_ioport) + pmtmr_ioport = fadt->V1_pm_tmr_blk; } else { /* FADT rev. 1 */ pmtmr_ioport = fadt->V1_pm_tmr_blk; _