summary refs log tree commit diff stats
path: root/hw/acpi/piix4.c
diff options
context:
space:
mode:
authorIsaku Yamahata <isaku.yamahata@intel.com>2021-02-17 21:51:12 -0800
committerMichael S. Tsirkin <mst@redhat.com>2021-02-23 10:58:42 -0500
commit6be8cf56bc8bda2ed9a070bdb04446191f31acc9 (patch)
tree653991a53ad2e88f6386fbbe4f9daabe2a6d4d7f /hw/acpi/piix4.c
parent24cd04fce06b0d54e5ca2c12f20f714894a78b95 (diff)
downloadfocaccia-qemu-6be8cf56bc8bda2ed9a070bdb04446191f31acc9.tar.gz
focaccia-qemu-6be8cf56bc8bda2ed9a070bdb04446191f31acc9.zip
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 'hw/acpi/piix4.c')
-rw-r--r--hw/acpi/piix4.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index 30dd9b2309..1efc0ded9f 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -497,7 +497,8 @@ static void piix4_pm_realize(PCIDevice *dev, Error **errp)
 
     acpi_pm_tmr_init(&s->ar, pm_tmr_timer, &s->io);
     acpi_pm1_evt_init(&s->ar, pm_tmr_timer, &s->io);
-    acpi_pm1_cnt_init(&s->ar, &s->io, s->disable_s3, s->disable_s4, s->s4_val);
+    acpi_pm1_cnt_init(&s->ar, &s->io, s->disable_s3, s->disable_s4, s->s4_val,
+                      !s->smm_compat && !s->smm_enabled);
     acpi_gpe_init(&s->ar, GPE_LEN);
 
     s->powerdown_notifier.notify = piix4_pm_powerdown_req;