diff options
| author | Isaku Yamahata <isaku.yamahata@intel.com> | 2021-02-17 21:51:12 -0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2021-02-23 10:58:42 -0500 |
| commit | 6be8cf56bc8bda2ed9a070bdb04446191f31acc9 (patch) | |
| tree | 653991a53ad2e88f6386fbbe4f9daabe2a6d4d7f /linux-headers | |
| parent | 24cd04fce06b0d54e5ca2c12f20f714894a78b95 (diff) | |
acpi/core: always set SCI_EN when SMM isn't supported
If SMM is not supported, ACPI fixed hardware doesn't support
legacy-mode. ACPI-only platform. Where SCI_EN in PM1_CNT register is
always set.
The bit tells OS legacy mode(SCI_EN cleared) or ACPI mode(SCI_EN set).
With the next patch (setting fadt.smi_cmd = 0 when smm isn't enabled),
guest Linux tries to switch to ACPI mode, finds smi_cmd = 0, and then
fails to initialize acpi subsystem. This patch proactively fixes it.
This patch changes guest ABI. To keep compatibility, use
"smm-compat" introduced by earlier patch. If the property is true,
disable new behavior.
ACPI spec 4.8.10.1 PM1 Event Grouping
PM1 Eanble Registers
> For ACPI-only platforms (where SCI_EN is always set)
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-Id: <500f62081626997e46f96377393d3662211763a8.1613615732.git.isaku.yamahata@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'linux-headers')
0 files changed, 0 insertions, 0 deletions