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author | Daniel Baumann <mail@daniel-baumann.ch> | 2025-06-06 10:05:23 +0000 |
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committer | Daniel Baumann <mail@daniel-baumann.ch> | 2025-06-06 10:05:23 +0000 |
commit | 755cc582a2473d06f3a2131d506d0311cc70e9f9 (patch) | |
tree | 3efb1ddb8d57bbb4539ac0d229b384871c57820f /hw/acpi/pcihp.c | |
parent | Initial commit. (diff) | |
download | qemu-upstream.tar.xz qemu-upstream.zip |
Adding upstream version 1:7.2+dfsg.upstream/1%7.2+dfsgupstream
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to 'hw/acpi/pcihp.c')
-rw-r--r-- | hw/acpi/pcihp.c | 570 |
1 files changed, 570 insertions, 0 deletions
diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c new file mode 100644 index 00000000..84d75e6b --- /dev/null +++ b/hw/acpi/pcihp.c @@ -0,0 +1,570 @@ +/* + * QEMU<->ACPI BIOS PCI hotplug interface + * + * QEMU supports PCI hotplug via ACPI. This module + * implements the interface between QEMU and the ACPI BIOS. + * Interface specification - see docs/specs/acpi_pci_hotplug.txt + * + * Copyright (c) 2013, Red Hat Inc, Michael S. Tsirkin (mst@redhat.com) + * Copyright (c) 2006 Fabrice Bellard + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/> + * + * Contributions after 2012-01-13 are licensed under the terms of the + * GNU GPL, version 2 or (at your option) any later version. + */ + +#include "qemu/osdep.h" +#include "hw/acpi/pcihp.h" + +#include "hw/pci-host/i440fx.h" +#include "hw/pci/pci.h" +#include "hw/pci/pci_bridge.h" +#include "hw/pci/pci_host.h" +#include "hw/pci/pcie_port.h" +#include "hw/pci-bridge/xio3130_downstream.h" +#include "hw/i386/acpi-build.h" +#include "hw/acpi/acpi.h" +#include "hw/pci/pci_bus.h" +#include "migration/vmstate.h" +#include "qapi/error.h" +#include "qom/qom-qobject.h" +#include "trace.h" + +#define ACPI_PCIHP_SIZE 0x0018 +#define PCI_UP_BASE 0x0000 +#define PCI_DOWN_BASE 0x0004 +#define PCI_EJ_BASE 0x0008 +#define PCI_RMV_BASE 0x000c +#define PCI_SEL_BASE 0x0010 +#define PCI_AIDX_BASE 0x0014 + +typedef struct AcpiPciHpFind { + int bsel; + PCIBus *bus; +} AcpiPciHpFind; + +static gint g_cmp_uint32(gconstpointer a, gconstpointer b, gpointer user_data) +{ + return a - b; +} + +static GSequence *pci_acpi_index_list(void) +{ + static GSequence *used_acpi_index_list; + + if (!used_acpi_index_list) { + used_acpi_index_list = g_sequence_new(NULL); + } + return used_acpi_index_list; +} + +static int acpi_pcihp_get_bsel(PCIBus *bus) +{ + Error *local_err = NULL; + uint64_t bsel = object_property_get_uint(OBJECT(bus), ACPI_PCIHP_PROP_BSEL, + &local_err); + + if (local_err || bsel >= ACPI_PCIHP_MAX_HOTPLUG_BUS) { + if (local_err) { + error_free(local_err); + } + return -1; + } else { + return bsel; + } +} + +/* Assign BSEL property to all buses. In the future, this can be changed + * to only assign to buses that support hotplug. + */ +static void *acpi_set_bsel(PCIBus *bus, void *opaque) +{ + unsigned *bsel_alloc = opaque; + unsigned *bus_bsel; + + if (qbus_is_hotpluggable(BUS(bus))) { + bus_bsel = g_malloc(sizeof *bus_bsel); + + *bus_bsel = (*bsel_alloc)++; + object_property_add_uint32_ptr(OBJECT(bus), ACPI_PCIHP_PROP_BSEL, + bus_bsel, OBJ_PROP_FLAG_READ); + } + + return bsel_alloc; +} + +static void acpi_set_pci_info(void) +{ + static bool bsel_is_set; + Object *host = acpi_get_i386_pci_host(); + PCIBus *bus; + unsigned bsel_alloc = ACPI_PCIHP_BSEL_DEFAULT; + + if (bsel_is_set) { + return; + } + bsel_is_set = true; + + if (!host) { + return; + } + + bus = PCI_HOST_BRIDGE(host)->bus; + if (bus) { + /* Scan all PCI buses. Set property to enable acpi based hotplug. */ + pci_for_each_bus_depth_first(bus, acpi_set_bsel, NULL, &bsel_alloc); + } +} + +static void acpi_pcihp_disable_root_bus(void) +{ + Object *host = acpi_get_i386_pci_host(); + PCIBus *bus; + + bus = PCI_HOST_BRIDGE(host)->bus; + if (bus && qbus_is_hotpluggable(BUS(bus))) { + /* setting the hotplug handler to NULL makes the bus non-hotpluggable */ + qbus_set_hotplug_handler(BUS(bus), NULL); + } + + return; +} + +static void acpi_pcihp_test_hotplug_bus(PCIBus *bus, void *opaque) +{ + AcpiPciHpFind *find = opaque; + if (find->bsel == acpi_pcihp_get_bsel(bus)) { + find->bus = bus; + } +} + +static PCIBus *acpi_pcihp_find_hotplug_bus(AcpiPciHpState *s, int bsel) +{ + AcpiPciHpFind find = { .bsel = bsel, .bus = NULL }; + + if (bsel < 0) { + return NULL; + } + + pci_for_each_bus(s->root, acpi_pcihp_test_hotplug_bus, &find); + + /* Make bsel 0 eject root bus if bsel property is not set, + * for compatibility with non acpi setups. + * TODO: really needed? + */ + if (!bsel && !find.bus) { + find.bus = s->root; + } + + /* + * Check if find.bus is actually hotpluggable. If bsel is set to + * NULL for example on the root bus in order to make it + * non-hotpluggable, find.bus will match the root bus when bsel + * is 0. See acpi_pcihp_test_hotplug_bus() above. Since the + * bus is not hotpluggable however, we should not select the bus. + * Instead, we should set find.bus to NULL in that case. In the check + * below, we generalize this case for all buses, not just the root bus. + * The callers of this function check for a null return value and + * handle them appropriately. + */ + if (find.bus && !qbus_is_hotpluggable(BUS(find.bus))) { + find.bus = NULL; + } + return find.bus; +} + +static bool acpi_pcihp_pc_no_hotplug(AcpiPciHpState *s, PCIDevice *dev) +{ + PCIDeviceClass *pc = PCI_DEVICE_GET_CLASS(dev); + DeviceClass *dc = DEVICE_GET_CLASS(dev); + /* + * ACPI doesn't allow hotplug of bridge devices. Don't allow + * hot-unplug of bridge devices unless they were added by hotplug + * (and so, not described by acpi). + * + * Don't allow hot-unplug of SR-IOV Virtual Functions, as they + * will be removed implicitly, when Physical Function is unplugged. + */ + return (pc->is_bridge && !dev->qdev.hotplugged) || !dc->hotpluggable || + pci_is_vf(dev); +} + +static void acpi_pcihp_eject_slot(AcpiPciHpState *s, unsigned bsel, unsigned slots) +{ + HotplugHandler *hotplug_ctrl; + BusChild *kid, *next; + int slot = ctz32(slots); + PCIBus *bus = acpi_pcihp_find_hotplug_bus(s, bsel); + + trace_acpi_pci_eject_slot(bsel, slot); + + if (!bus || slot > 31) { + return; + } + + /* Mark request as complete */ + s->acpi_pcihp_pci_status[bsel].down &= ~(1U << slot); + s->acpi_pcihp_pci_status[bsel].up &= ~(1U << slot); + + QTAILQ_FOREACH_SAFE(kid, &bus->qbus.children, sibling, next) { + DeviceState *qdev = kid->child; + PCIDevice *dev = PCI_DEVICE(qdev); + if (PCI_SLOT(dev->devfn) == slot) { + if (!acpi_pcihp_pc_no_hotplug(s, dev)) { + /* + * partially_hotplugged is used by virtio-net failover: + * failover has asked the guest OS to unplug the device + * but we need to keep some references to the device + * to be able to plug it back in case of failure so + * we don't execute hotplug_handler_unplug(). + */ + if (dev->partially_hotplugged) { + /* + * pending_deleted_event is set to true when + * virtio-net failover asks to unplug the device, + * and set to false here when the operation is done + * This is used by the migration loop to detect the + * end of the operation and really start the migration. + */ + qdev->pending_deleted_event = false; + } else { + hotplug_ctrl = qdev_get_hotplug_handler(qdev); + hotplug_handler_unplug(hotplug_ctrl, qdev, &error_abort); + object_unparent(OBJECT(qdev)); + } + } + } + } +} + +static void acpi_pcihp_update_hotplug_bus(AcpiPciHpState *s, int bsel) +{ + BusChild *kid, *next; + PCIBus *bus = acpi_pcihp_find_hotplug_bus(s, bsel); + + /* Execute any pending removes during reset */ + while (s->acpi_pcihp_pci_status[bsel].down) { + acpi_pcihp_eject_slot(s, bsel, s->acpi_pcihp_pci_status[bsel].down); + } + + s->acpi_pcihp_pci_status[bsel].hotplug_enable = ~0; + + if (!bus) { + return; + } + QTAILQ_FOREACH_SAFE(kid, &bus->qbus.children, sibling, next) { + DeviceState *qdev = kid->child; + PCIDevice *pdev = PCI_DEVICE(qdev); + int slot = PCI_SLOT(pdev->devfn); + + if (acpi_pcihp_pc_no_hotplug(s, pdev)) { + s->acpi_pcihp_pci_status[bsel].hotplug_enable &= ~(1U << slot); + } + } +} + +static void acpi_pcihp_update(AcpiPciHpState *s) +{ + int i; + + for (i = 0; i < ACPI_PCIHP_MAX_HOTPLUG_BUS; ++i) { + acpi_pcihp_update_hotplug_bus(s, i); + } +} + +void acpi_pcihp_reset(AcpiPciHpState *s, bool acpihp_root_off) +{ + if (acpihp_root_off) { + acpi_pcihp_disable_root_bus(); + } + acpi_set_pci_info(); + acpi_pcihp_update(s); +} + +#define ONBOARD_INDEX_MAX (16 * 1024 - 1) + +void acpi_pcihp_device_pre_plug_cb(HotplugHandler *hotplug_dev, + DeviceState *dev, Error **errp) +{ + PCIDevice *pdev = PCI_DEVICE(dev); + + /* Only hotplugged devices need the hotplug capability. */ + if (dev->hotplugged && + acpi_pcihp_get_bsel(pci_get_bus(pdev)) < 0) { + error_setg(errp, "Unsupported bus. Bus doesn't have property '" + ACPI_PCIHP_PROP_BSEL "' set"); + return; + } + + /* + * capped by systemd (see: udev-builtin-net_id.c) + * as it's the only known user honor it to avoid users + * misconfigure QEMU and then wonder why acpi-index doesn't work + */ + if (pdev->acpi_index > ONBOARD_INDEX_MAX) { + error_setg(errp, "acpi-index should be less or equal to %u", + ONBOARD_INDEX_MAX); + return; + } + + /* + * make sure that acpi-index is unique across all present PCI devices + */ + if (pdev->acpi_index) { + GSequence *used_indexes = pci_acpi_index_list(); + + if (g_sequence_lookup(used_indexes, GINT_TO_POINTER(pdev->acpi_index), + g_cmp_uint32, NULL)) { + error_setg(errp, "a PCI device with acpi-index = %" PRIu32 + " already exist", pdev->acpi_index); + return; + } + g_sequence_insert_sorted(used_indexes, + GINT_TO_POINTER(pdev->acpi_index), + g_cmp_uint32, NULL); + } +} + +void acpi_pcihp_device_plug_cb(HotplugHandler *hotplug_dev, AcpiPciHpState *s, + DeviceState *dev, Error **errp) +{ + PCIDevice *pdev = PCI_DEVICE(dev); + int slot = PCI_SLOT(pdev->devfn); + PCIDevice *bridge; + PCIBus *bus; + int bsel; + + /* Don't send event when device is enabled during qemu machine creation: + * it is present on boot, no hotplug event is necessary. We do send an + * event when the device is disabled later. */ + if (!dev->hotplugged) { + /* + * Overwrite the default hotplug handler with the ACPI PCI one + * for cold plugged bridges only. + */ + if (!s->legacy_piix && + object_dynamic_cast(OBJECT(dev), TYPE_PCI_BRIDGE)) { + PCIBus *sec = pci_bridge_get_sec_bus(PCI_BRIDGE(pdev)); + + /* Remove all hot-plug handlers if hot-plug is disabled on slot */ + if (object_dynamic_cast(OBJECT(dev), TYPE_PCIE_SLOT) && + !PCIE_SLOT(pdev)->hotplug) { + qbus_set_hotplug_handler(BUS(sec), NULL); + return; + } + + qbus_set_hotplug_handler(BUS(sec), OBJECT(hotplug_dev)); + /* We don't have to overwrite any other hotplug handler yet */ + assert(QLIST_EMPTY(&sec->child)); + } + + return; + } + + bus = pci_get_bus(pdev); + bridge = pci_bridge_get_device(bus); + if (object_dynamic_cast(OBJECT(bridge), TYPE_PCIE_ROOT_PORT) || + object_dynamic_cast(OBJECT(bridge), TYPE_XIO3130_DOWNSTREAM)) { + pcie_cap_slot_enable_power(bridge); + } + + bsel = acpi_pcihp_get_bsel(bus); + g_assert(bsel >= 0); + s->acpi_pcihp_pci_status[bsel].up |= (1U << slot); + acpi_send_event(DEVICE(hotplug_dev), ACPI_PCI_HOTPLUG_STATUS); +} + +void acpi_pcihp_device_unplug_cb(HotplugHandler *hotplug_dev, AcpiPciHpState *s, + DeviceState *dev, Error **errp) +{ + PCIDevice *pdev = PCI_DEVICE(dev); + + trace_acpi_pci_unplug(PCI_SLOT(pdev->devfn), + acpi_pcihp_get_bsel(pci_get_bus(pdev))); + + /* + * clean up acpi-index so it could reused by another device + */ + if (pdev->acpi_index) { + GSequence *used_indexes = pci_acpi_index_list(); + + g_sequence_remove(g_sequence_lookup(used_indexes, + GINT_TO_POINTER(pdev->acpi_index), + g_cmp_uint32, NULL)); + } + + qdev_unrealize(dev); +} + +void acpi_pcihp_device_unplug_request_cb(HotplugHandler *hotplug_dev, + AcpiPciHpState *s, DeviceState *dev, + Error **errp) +{ + PCIDevice *pdev = PCI_DEVICE(dev); + int slot = PCI_SLOT(pdev->devfn); + int bsel = acpi_pcihp_get_bsel(pci_get_bus(pdev)); + + trace_acpi_pci_unplug_request(bsel, slot); + + if (bsel < 0) { + error_setg(errp, "Unsupported bus. Bus doesn't have property '" + ACPI_PCIHP_PROP_BSEL "' set"); + return; + } + + /* + * pending_deleted_event is used by virtio-net failover to detect the + * end of the unplug operation, the flag is set to false in + * acpi_pcihp_eject_slot() when the operation is completed. + */ + pdev->qdev.pending_deleted_event = true; + s->acpi_pcihp_pci_status[bsel].down |= (1U << slot); + acpi_send_event(DEVICE(hotplug_dev), ACPI_PCI_HOTPLUG_STATUS); +} + +static uint64_t pci_read(void *opaque, hwaddr addr, unsigned int size) +{ + AcpiPciHpState *s = opaque; + uint32_t val = 0; + int bsel = s->hotplug_select; + + if (bsel < 0 || bsel >= ACPI_PCIHP_MAX_HOTPLUG_BUS) { + return 0; + } + + switch (addr) { + case PCI_UP_BASE: + val = s->acpi_pcihp_pci_status[bsel].up; + if (!s->legacy_piix) { + s->acpi_pcihp_pci_status[bsel].up = 0; + } + trace_acpi_pci_up_read(val); + break; + case PCI_DOWN_BASE: + val = s->acpi_pcihp_pci_status[bsel].down; + trace_acpi_pci_down_read(val); + break; + case PCI_EJ_BASE: + trace_acpi_pci_features_read(val); + break; + case PCI_RMV_BASE: + val = s->acpi_pcihp_pci_status[bsel].hotplug_enable; + trace_acpi_pci_rmv_read(val); + break; + case PCI_SEL_BASE: + val = s->hotplug_select; + trace_acpi_pci_sel_read(val); + break; + case PCI_AIDX_BASE: + val = s->acpi_index; + s->acpi_index = 0; + trace_acpi_pci_acpi_index_read(val); + break; + default: + break; + } + + return val; +} + +static void pci_write(void *opaque, hwaddr addr, uint64_t data, + unsigned int size) +{ + int slot; + PCIBus *bus; + BusChild *kid, *next; + AcpiPciHpState *s = opaque; + + s->acpi_index = 0; + switch (addr) { + case PCI_AIDX_BASE: + /* + * fetch acpi-index for specified slot so that follow up read from + * PCI_AIDX_BASE can return it to guest + */ + slot = ctz32(data); + + if (s->hotplug_select >= ACPI_PCIHP_MAX_HOTPLUG_BUS) { + break; + } + + bus = acpi_pcihp_find_hotplug_bus(s, s->hotplug_select); + if (!bus) { + break; + } + QTAILQ_FOREACH_SAFE(kid, &bus->qbus.children, sibling, next) { + Object *o = OBJECT(kid->child); + PCIDevice *dev = PCI_DEVICE(o); + if (PCI_SLOT(dev->devfn) == slot) { + s->acpi_index = object_property_get_uint(o, "acpi-index", NULL); + break; + } + } + trace_acpi_pci_acpi_index_write(s->hotplug_select, slot, s->acpi_index); + break; + case PCI_EJ_BASE: + if (s->hotplug_select >= ACPI_PCIHP_MAX_HOTPLUG_BUS) { + break; + } + acpi_pcihp_eject_slot(s, s->hotplug_select, data); + trace_acpi_pci_ej_write(addr, data); + break; + case PCI_SEL_BASE: + s->hotplug_select = s->legacy_piix ? ACPI_PCIHP_BSEL_DEFAULT : data; + trace_acpi_pci_sel_write(addr, data); + default: + break; + } +} + +static const MemoryRegionOps acpi_pcihp_io_ops = { + .read = pci_read, + .write = pci_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, +}; + +void acpi_pcihp_init(Object *owner, AcpiPciHpState *s, PCIBus *root_bus, + MemoryRegion *address_space_io, bool bridges_enabled, + uint16_t io_base) +{ + s->io_len = ACPI_PCIHP_SIZE; + s->io_base = io_base; + + s->root = root_bus; + s->legacy_piix = !bridges_enabled; + + memory_region_init_io(&s->io, owner, &acpi_pcihp_io_ops, s, + "acpi-pci-hotplug", s->io_len); + memory_region_add_subregion(address_space_io, s->io_base, &s->io); + + object_property_add_uint16_ptr(owner, ACPI_PCIHP_IO_BASE_PROP, &s->io_base, + OBJ_PROP_FLAG_READ); + object_property_add_uint16_ptr(owner, ACPI_PCIHP_IO_LEN_PROP, &s->io_len, + OBJ_PROP_FLAG_READ); +} + +const VMStateDescription vmstate_acpi_pcihp_pci_status = { + .name = "acpi_pcihp_pci_status", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32(up, AcpiPciHpPciStatus), + VMSTATE_UINT32(down, AcpiPciHpPciStatus), + VMSTATE_END_OF_LIST() + } +}; |