Hi Eric,
On 5/14/25 14:00, Eric Auger wrote:
This series enables ACPI PCI hotplug/hotunplug on ARM
and makes it default for 10.1 machine type. This aligns with
x86 q35 machine. Expected benefits should be similar to
those listed in [1].
It is still possible to disable it using a virt machine
option: virt,acpi-pcihp=off and restore the legacy behavior.
The infrastructure used in x86 is heavily reused and a
huge part of the series consists in moving code from
hw/i386/acpi-build.c to a generic place and slightly
adapting it to make it usable on ARM. The DSDT table is
augmented to support ACPI PCI hotplug elements.
On ARM we use use a GED event to notify the OS about
hotplug events.
I have not noticed any tests/qtest/bios-tables-test failures
neither on x86 nor ARM. x86 DSDT table has not changed.
ARM DSDT table definitively has but there are no tests
impacted. ARM misses hotplug tests that do exist on x86. This
most probably should be considered in the future.
I've just posted a v1 for a acpi-pcihp=on test:
https://mail.gnu.org/archive/html/qemu-devel/2025-05/msg05824.html
The odd thing is that I noticed failures in the existing aarch64
acpi tests in tests/qtest/bios-tables-test. At least the rename
of the variable 'CTRL' to 'Local0' in the _OSC method should cause
a mismatch against the current base DSDT? So I had to handle it
via patches 1/5, 2/5, and 3/5. The diff is in the 3/5 commit body.
Cheers,
Gustavo
Best Regards
Eric
This series can be found at:
https://github.com/eauger/qemu/tree/arm-acpi-pcihp-v1
previous RFC:
https://github.com/eauger/qemu/tree/arm-acpi-pcihp-rfc
History:
RFC -> v1:
- First 3 trivial patches were pulled separately
- Fix of the register region size (0x18), ie. ACPI_PCIHP_SIZE
- addition of aml_pci_edsm which was not called in RFC
- acpi-index feature is now fixed. vms->bus was not set on
acpi_pcihp_init. The init sequence is still hacky though. Suggestions
appreciated.
[1] [PATCH v6 0/6] Use ACPI PCI hot-plug for Q35
https://lore.kernel.org/all/20210713004205.775386-1-jus...@redhat.com/
Eric Auger (22):
hw/i386/acpi-build: Make aml_pci_device_dsm() static
hw/arm/virt: Introduce machine state acpi pcihp flags and props
hw/acpi: Rename and move build_x86_acpi_pci_hotplug to pcihp
hw/pci-host/gpex-acpi: Add native_pci_hotplug arg to
acpi_dsdt_add_pci_osc
hw/pci-host/gpex-acpi: Split host bridge OSC and DSM generation
hw/pci-host/gpex-acpi: Propagate hotplug type info from virt machine
downto gpex
hw/i386/acpi-build: Turn build_q35_osc_method into a generic method
hw/pci-host/gpex-acpi: Use build_pci_host_bridge_osc_method
hw/i386/acpi-build: Introduce build_append_pcihp_resources() helper
hw/acpi/pcihp: Add an AmlRegionSpace arg to build_acpi_pci_hotplug
hw/i386/acpi-build: Move build_append_notification_callback to pcihp
hw/i386/acpi-build: Move build_append_pci_bus_devices/pcihp_slots to
pcihp
hw/i386/acpi-build: Introduce and use acpi_get_pci_host
hw/i386/acpi-build: Move aml_pci_edsm to a generic place
hw/arm/virt-acpi-build: Modify the DSDT ACPI table to enable ACPI PCI
hotplug
hw/acpi/ged: Prepare the device to react to PCI hotplug events
hw/acpi/ged: Call pcihp plug callbacks in hotplug handler
implementation
hw/acpi/ged: Support migration of AcpiPciHpState
hw/core/sysbus: Introduce sysbus_mmio_map_name() helper
hw/arm/virt: Let virt support pci hotplug/unplug GED event
hw/arm/virt: Plug pcihp hotplug/hotunplug callbacks
hw/arm/virt: Use ACPI PCI hotplug by default
hw/i386/acpi-build.h | 4 -
include/hw/acpi/aml-build.h | 2 +
include/hw/acpi/generic_event_device.h | 5 +
include/hw/acpi/pci.h | 4 +-
include/hw/acpi/pcihp.h | 19 +-
include/hw/arm/virt.h | 4 +
include/hw/pci-host/gpex.h | 1 +
include/hw/sysbus.h | 1 +
hw/acpi/aml-build.c | 50 +++
hw/acpi/generic_event_device.c | 55 +++
hw/acpi/pci.c | 20 +
hw/acpi/pcihp.c | 482 ++++++++++++++++++++-
hw/arm/virt-acpi-build.c | 27 ++
hw/arm/virt.c | 107 ++++-
hw/core/sysbus.c | 11 +
hw/i386/acpi-build.c | 552 +------------------------
hw/pci-host/gpex-acpi.c | 75 +---
hw/arm/Kconfig | 2 +
18 files changed, 806 insertions(+), 615 deletions(-)
