Commit 6be8cf56bc made sure that SCI is enabled in PM1.CNT
on reset in acpi_only mode by modifying acpi_pm1_cnt_reset() and
that worked for q35 as expected.
The function was introduced by commit
eaba51c573 (acpi, acpi_piix, vt82c686: factor out PM1_CNT logic)
that forgot to actually call it at piix4 reset time and as result
SCI_EN wasn't set as was expected by 6be8cf56bc in acpi_only mode.
So Windows crashes when it notices that SCI_EN is not set and FADT is
not providing information about how to enable it anymore.
Reproducer:
qemu-system-x86_64 -enable-kvm -M pc-i440fx-6.0,smm=off -cdrom any_windows_10x64.iso
Fix it by calling acpi_pm1_cnt_reset() at piix4 reset time.
Occasionally this patch adds reset acpi PM related registers on
piix4 reset time and de-assert sci.
piix4_pm_realize() initializes acpi pm tmr, evt, cnt and gpe.
Reset them on device reset. pm_reset() in ich9.c correctly calls
corresponding reset functions.
Fixes: 6be8cf56bc (acpi/core: always set SCI_EN when SMM isn't supported)
Reported-by: Reinoud Zandijk <reinoud@NetBSD.org>
Co-developed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-Id: <8a5bbd19727045ec863523830078dd4ca63f6a9a.1616532563.git.isaku.yamahata@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>