On Mon, 16 Jun 2025 11:46:49 +0200
Eric Auger <eric.au...@redhat.com> wrote:
> QEMU will notify the OS about PCI hotplug/hotunplug events through
> GED interrupts. Let the GED device handle a new PCI hotplug event.
> On its occurrence it calls the \\_SB.PCI0.PCNT method with the BLCK
> mutex held.
>
> The GED device uses a dedicated MMIO region that will be mapped
> by the machine code.
> At this point the GED still does not support PCI device hotplug in
> its TYPE_HOTPLUG_HANDLER implementation. This will come in a
> subsequent patch.
looks out of order, perhaps it should be before this patch
>
> Signed-off-by: Eric Auger <eric.au...@redhat.com>
>
> ---
> v2 -> v3:
> - pcihp_init and reset are put in ged code instead of machine code
> (Igor)
>
> v1 -> v2:
> - Introduce ACPI_PCIHP_REGION_NAME
> ---
> include/hw/acpi/generic_event_device.h | 4 ++++
> hw/acpi/generic_event_device.c | 26 ++++++++++++++++++++++++++
> hw/acpi/pcihp.c | 1 -
> 3 files changed, 30 insertions(+), 1 deletion(-)
>
> diff --git a/include/hw/acpi/generic_event_device.h
> b/include/hw/acpi/generic_event_device.h
> index f5ffa67a39..ec8e1abe0a 100644
> --- a/include/hw/acpi/generic_event_device.h
> +++ b/include/hw/acpi/generic_event_device.h
> @@ -102,6 +102,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(AcpiGedState, ACPI_GED)
> #define ACPI_GED_PWR_DOWN_EVT 0x2
> #define ACPI_GED_NVDIMM_HOTPLUG_EVT 0x4
> #define ACPI_GED_CPU_HOTPLUG_EVT 0x8
> +#define ACPI_GED_PCI_HOTPLUG_EVT 0x10
>
> typedef struct GEDState {
> MemoryRegion evt;
> @@ -109,6 +110,8 @@ typedef struct GEDState {
> uint32_t sel;
> } GEDState;
>
> +#define ACPI_PCIHP_REGION_NAME "pcihp container"
> +
> struct AcpiGedState {
> SysBusDevice parent_obj;
> MemHotplugState memhp_state;
> @@ -116,6 +119,7 @@ struct AcpiGedState {
> CPUHotplugState cpuhp_state;
> MemoryRegion container_cpuhp;
> AcpiPciHpState pcihp_state;
> + MemoryRegion container_pcihp;
> GEDState ged_state;
> uint32_t ged_event_bitmap;
> qemu_irq irq;
> diff --git a/hw/acpi/generic_event_device.c b/hw/acpi/generic_event_device.c
> index ef1c1ec51f..b4eefb0106 100644
> --- a/hw/acpi/generic_event_device.c
> +++ b/hw/acpi/generic_event_device.c
> @@ -12,6 +12,7 @@
> #include "qemu/osdep.h"
> #include "qapi/error.h"
> #include "hw/acpi/acpi.h"
> +#include "hw/acpi/pcihp.h"
> #include "hw/acpi/generic_event_device.h"
> #include "hw/pci/pci.h"
> #include "hw/irq.h"
> @@ -27,6 +28,7 @@ static const uint32_t ged_supported_events[] = {
> ACPI_GED_PWR_DOWN_EVT,
> ACPI_GED_NVDIMM_HOTPLUG_EVT,
> ACPI_GED_CPU_HOTPLUG_EVT,
> + ACPI_GED_PCI_HOTPLUG_EVT,
> };
>
> /*
> @@ -122,6 +124,12 @@ void build_ged_aml(Aml *table, const char *name,
> HotplugHandler *hotplug_dev,
> aml_notify(aml_name("\\_SB.NVDR"),
> aml_int(0x80)));
> break;
> + case ACPI_GED_PCI_HOTPLUG_EVT:
> + aml_append(if_ctx,
> + aml_acquire(aml_name("\\_SB.PCI0.BLCK"), 0xFFFF));
> + aml_append(if_ctx, aml_call0("\\_SB.PCI0.PCNT"));
> + aml_append(if_ctx, aml_release(aml_name("\\_SB.PCI0.BLCK")));
> + break;
> default:
> /*
> * Please make sure all the events in ged_supported_events[]
> @@ -300,6 +308,8 @@ static void acpi_ged_send_event(AcpiDeviceIf *adev,
> AcpiEventStatusBits ev)
> sel = ACPI_GED_NVDIMM_HOTPLUG_EVT;
> } else if (ev & ACPI_CPU_HOTPLUG_STATUS) {
> sel = ACPI_GED_CPU_HOTPLUG_EVT;
> + } else if (ev & ACPI_PCI_HOTPLUG_STATUS) {
> + sel = ACPI_GED_PCI_HOTPLUG_EVT;
> } else {
> /* Unknown event. Return without generating interrupt. */
> warn_report("GED: Unsupported event %d. No irq injected", ev);
> @@ -433,6 +443,12 @@ static void acpi_ged_realize(DeviceState *dev, Error
> **errp)
> cpu_hotplug_hw_init(&s->container_cpuhp, OBJECT(dev),
> &s->cpuhp_state, 0);
> break;
> + case ACPI_GED_PCI_HOTPLUG_EVT:
> + memory_region_init(&s->container_pcihp, OBJECT(dev),
> + ACPI_PCIHP_REGION_NAME, ACPI_PCIHP_SIZE);
> + sysbus_init_mmio(sbd, &s->container_pcihp);
> + acpi_pcihp_init(OBJECT(s), &s->pcihp_state,
> + s->pcihp_state.root, &s->container_pcihp, 0);
> }
> ged_events--;
> }
> @@ -474,6 +490,15 @@ static void acpi_ged_initfn(Object *obj)
> sysbus_init_mmio(sbd, &ged_st->regs);
> }
>
> +static void ged_reset(DeviceState *dev)
> +{
> + AcpiGedState *s = ACPI_GED(dev);
> +
> + if (s->pcihp_state.use_acpi_hotplug_bridge) {
> + acpi_pcihp_reset(&s->pcihp_state);
> + }
> +}
> +
> static void acpi_ged_class_init(ObjectClass *class, const void *data)
> {
> DeviceClass *dc = DEVICE_CLASS(class);
> @@ -488,6 +513,7 @@ static void acpi_ged_class_init(ObjectClass *class, const
> void *data)
> hc->plug = acpi_ged_device_plug_cb;
> hc->unplug_request = acpi_ged_unplug_request_cb;
> hc->unplug = acpi_ged_unplug_cb;
> + device_class_set_legacy_reset(dc, ged_reset);
>
> adevc->ospm_status = acpi_ged_ospm_status;
> adevc->send_event = acpi_ged_send_event;
> diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c
> index e79a24b821..36492aa0d9 100644
> --- a/hw/acpi/pcihp.c
> +++ b/hw/acpi/pcihp.c
> @@ -43,7 +43,6 @@
> #include "qobject/qnum.h"
> #include "trace.h"
>
> -#define ACPI_PCIHP_SIZE 0x0018
> #define PCI_UP_BASE 0x0000
> #define PCI_DOWN_BASE 0x0004
> #define PCI_EJ_BASE 0x0008
