| Message ID | 20210513062642.3027987-7-jusual@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Use ACPI PCI hot-plug for Q35 | expand |
On Thu, 13 May 2021 08:26:41 +0200 Julia Suvorova <jusual@redhat.com> wrote: > Q35 has three different types of PCI devices hot-plug: PCIe Native, > SHPC Native and ACPI hot-plug. This patch changes the default choice > for cold-plugged bridges from PCIe Native to ACPI Hot-plug with > ability to use SHPC and PCIe Native for hot-plugged bridges. > > This is a list of the PCIe Native hot-plug issues that led to this > change: > * no racy behavior during boot (see 110c477c2ed) > * no delay during deleting - after the actual power off software > must wait at least 1 second before indicating about it. This case > is quite important for users, it even has its own bug: > https://bugzilla.redhat.com/show_bug.cgi?id=1594168 > * no timer-based behavior - in addition to the previous example, > the attention button has a 5-second waiting period, during which > the operation can be canceled with a second press. While this > looks fine for manual button control, automation will result in > the need to queue or drop events, and the software receiving > events in all sort of unspecified combinations of attention/power > indicator states, which is racy and uppredictable. > * fixes or reduces the likelihood of the bug: > * https://bugzilla.redhat.com/show_bug.cgi?id=1833187 > * https://bugzilla.redhat.com/show_bug.cgi?id=1657077 > * https://bugzilla.redhat.com/show_bug.cgi?id=1669931 > * https://bugzilla.redhat.com/show_bug.cgi?id=1678290 > > To return to PCIe Native hot-plug: > -global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=off > > Signed-off-by: Julia Suvorova <jusual@redhat.com> Reviewed-by: Igor Mammedov <imammedo@redhat.com> > --- > hw/acpi/ich9.c | 2 +- > hw/i386/pc.c | 4 +++- > 2 files changed, 4 insertions(+), 2 deletions(-) > > diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c > index f6819c4f2a..e7b2cd9719 100644 > --- a/hw/acpi/ich9.c > +++ b/hw/acpi/ich9.c > @@ -425,7 +425,7 @@ void ich9_pm_add_properties(Object *obj, ICH9LPCPMRegs *pm) > pm->disable_s3 = 0; > pm->disable_s4 = 0; > pm->s4_val = 2; > - pm->use_acpi_hotplug_bridge = false; > + pm->use_acpi_hotplug_bridge = true; > > object_property_add_uint32_ptr(obj, ACPI_PM_PROP_PM_IO_BASE, > &pm->pm_io_base, OBJ_PROP_FLAG_READ); > diff --git a/hw/i386/pc.c b/hw/i386/pc.c > index 8cfaf216e7..5c2d3d11a2 100644 > --- a/hw/i386/pc.c > +++ b/hw/i386/pc.c > @@ -94,7 +94,9 @@ > #include "trace.h" > #include CONFIG_DEVICES > > -GlobalProperty pc_compat_6_0[] = {}; > +GlobalProperty pc_compat_6_0[] = { > + { "ICH9-LPC", "acpi-pci-hotplug-with-bridge-support", "off" }, > +}; > const size_t pc_compat_6_0_len = G_N_ELEMENTS(pc_compat_6_0); > > GlobalProperty pc_compat_5_2[] = {
diff --git a/hw/acpi/ich9.c b/hw/acpi/ich9.c index f6819c4f2a..e7b2cd9719 100644 --- a/hw/acpi/ich9.c +++ b/hw/acpi/ich9.c @@ -425,7 +425,7 @@ void ich9_pm_add_properties(Object *obj, ICH9LPCPMRegs *pm) pm->disable_s3 = 0; pm->disable_s4 = 0; pm->s4_val = 2; - pm->use_acpi_hotplug_bridge = false; + pm->use_acpi_hotplug_bridge = true; object_property_add_uint32_ptr(obj, ACPI_PM_PROP_PM_IO_BASE, &pm->pm_io_base, OBJ_PROP_FLAG_READ); diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 8cfaf216e7..5c2d3d11a2 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -94,7 +94,9 @@ #include "trace.h" #include CONFIG_DEVICES -GlobalProperty pc_compat_6_0[] = {}; +GlobalProperty pc_compat_6_0[] = { + { "ICH9-LPC", "acpi-pci-hotplug-with-bridge-support", "off" }, +}; const size_t pc_compat_6_0_len = G_N_ELEMENTS(pc_compat_6_0); GlobalProperty pc_compat_5_2[] = {
Q35 has three different types of PCI devices hot-plug: PCIe Native, SHPC Native and ACPI hot-plug. This patch changes the default choice for cold-plugged bridges from PCIe Native to ACPI Hot-plug with ability to use SHPC and PCIe Native for hot-plugged bridges. This is a list of the PCIe Native hot-plug issues that led to this change: * no racy behavior during boot (see 110c477c2ed) * no delay during deleting - after the actual power off software must wait at least 1 second before indicating about it. This case is quite important for users, it even has its own bug: https://bugzilla.redhat.com/show_bug.cgi?id=1594168 * no timer-based behavior - in addition to the previous example, the attention button has a 5-second waiting period, during which the operation can be canceled with a second press. While this looks fine for manual button control, automation will result in the need to queue or drop events, and the software receiving events in all sort of unspecified combinations of attention/power indicator states, which is racy and uppredictable. * fixes or reduces the likelihood of the bug: * https://bugzilla.redhat.com/show_bug.cgi?id=1833187 * https://bugzilla.redhat.com/show_bug.cgi?id=1657077 * https://bugzilla.redhat.com/show_bug.cgi?id=1669931 * https://bugzilla.redhat.com/show_bug.cgi?id=1678290 To return to PCIe Native hot-plug: -global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=off Signed-off-by: Julia Suvorova <jusual@redhat.com> --- hw/acpi/ich9.c | 2 +- hw/i386/pc.c | 4 +++- 2 files changed, 4 insertions(+), 2 deletions(-)