hw/acpi: Implement the SRAT GI affinity structure

ACPI spec provides a scheme to associate "Generic Initiators" [1]
(e.g. heterogeneous processors and accelerators, GPUs, and I/O devices with
integrated compute or DMA engines GPUs) with Proximity Domains. This is
achieved using Generic Initiator Affinity Structure in SRAT. During bootup,
Linux kernel parse the ACPI SRAT to determine the PXM ids and create a NUMA
node for each unique PXM ID encountered. Qemu currently do not implement
these structures while building SRAT.

Add GI structures while building VM ACPI SRAT. The association between
device and node are stored using acpi-generic-initiator object. Lookup
presence of all such objects and use them to build these structures.

The structure needs a PCI device handle [2] that consists of the device BDF.
The vfio-pci device corresponding to the acpi-generic-initiator object is
located to determine the BDF.

[1] ACPI Spec 6.3, Section 5.2.16.6
[2] ACPI Spec 6.3, Table 5.80

Cc: Jonathan Cameron <qemu-devel@nongnu.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cedric Le Goater <clg@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
Message-Id: <20240308145525.10886-3-ankita@nvidia.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/hw/acpi/acpi_generic_initiator.c b/hw/acpi/acpi_generic_initiator.c
index 130d6ae8c1d9e2e2b01f6009db06b84c77ad228a..17b9a052f59b0ecb598368415dc70971108a20bd 100644 (file)
--- a/hw/acpi/acpi_generic_initiator.c
+++ b/hw/acpi/acpi_generic_initiator.c
@@ -5,7 +5,9 @@
 
 #include "qemu/osdep.h"
 #include "hw/acpi/acpi_generic_initiator.h"
+#include "hw/acpi/aml-build.h"
 #include "hw/boards.h"
+#include "hw/pci/pci_device.h"
 #include "qemu/error-report.h"
 
 typedef struct AcpiGenericInitiatorClass {
@@ -47,6 +49,7 @@ static void acpi_generic_initiator_set_node(Object *obj, Visitor *v,
                                             Error **errp)
 {
     AcpiGenericInitiator *gi = ACPI_GENERIC_INITIATOR(obj);
+    MachineState *ms = MACHINE(qdev_get_machine());
     uint32_t value;
 
     if (!visit_type_uint32(v, name, &value, errp)) {
@@ -60,6 +63,7 @@ static void acpi_generic_initiator_set_node(Object *obj, Visitor *v,
     }
 
     gi->node = value;
+    ms->numa_state->nodes[gi->node].has_gi = true;
 }
 
 static void acpi_generic_initiator_class_init(ObjectClass *oc, void *data)
@@ -69,3 +73,76 @@ static void acpi_generic_initiator_class_init(ObjectClass *oc, void *data)
     object_class_property_add(oc, "node", "int", NULL,
         acpi_generic_initiator_set_node, NULL, NULL);
 }
+
+/*
+ * ACPI 6.3:
+ * Table 5-78 Generic Initiator Affinity Structure
+ */
+static void
+build_srat_generic_pci_initiator_affinity(GArray *table_data, int node,
+                                          PCIDeviceHandle *handle)
+{
+    uint8_t index;
+
+    build_append_int_noprefix(table_data, 5, 1);  /* Type */
+    build_append_int_noprefix(table_data, 32, 1); /* Length */
+    build_append_int_noprefix(table_data, 0, 1);  /* Reserved */
+    build_append_int_noprefix(table_data, 1, 1);  /* Device Handle Type: PCI */
+    build_append_int_noprefix(table_data, node, 4);  /* Proximity Domain */
+
+    /* Device Handle - PCI */
+    build_append_int_noprefix(table_data, handle->segment, 2);
+    build_append_int_noprefix(table_data, handle->bdf, 2);
+    for (index = 0; index < 12; index++) {
+        build_append_int_noprefix(table_data, 0, 1);
+    }
+
+    build_append_int_noprefix(table_data, GEN_AFFINITY_ENABLED, 4); /* Flags */
+    build_append_int_noprefix(table_data, 0, 4);     /* Reserved */
+}
+
+static int build_all_acpi_generic_initiators(Object *obj, void *opaque)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    AcpiGenericInitiator *gi;
+    GArray *table_data = opaque;
+    PCIDeviceHandle dev_handle;
+    PCIDevice *pci_dev;
+    Object *o;
+
+    if (!object_dynamic_cast(obj, TYPE_ACPI_GENERIC_INITIATOR)) {
+        return 0;
+    }
+
+    gi = ACPI_GENERIC_INITIATOR(obj);
+    if (gi->node >= ms->numa_state->num_nodes) {
+        error_printf("%s: Specified node %d is invalid.\n",
+                     TYPE_ACPI_GENERIC_INITIATOR, gi->node);
+        exit(1);
+    }
+
+    o = object_resolve_path_type(gi->pci_dev, TYPE_PCI_DEVICE, NULL);
+    if (!o) {
+        error_printf("%s: Specified device must be a PCI device.\n",
+                     TYPE_ACPI_GENERIC_INITIATOR);
+        exit(1);
+    }
+
+    pci_dev = PCI_DEVICE(o);
+
+    dev_handle.segment = 0;
+    dev_handle.bdf = PCI_BUILD_BDF(pci_bus_num(pci_get_bus(pci_dev)),
+                                               pci_dev->devfn);
+
+    build_srat_generic_pci_initiator_affinity(table_data,
+                                              gi->node, &dev_handle);
+
+    return 0;
+}
+
+void build_srat_generic_pci_initiator(GArray *table_data)
+{
+    object_child_foreach_recursive(object_get_root(),
+                                   build_all_acpi_generic_initiators,
+                                   table_data);
+}

diff --git a/hw/acpi/hmat.c b/hw/acpi/hmat.c
index 3042d223c825c361791b715d380acfe2582db9d2..2242981e1809e3e3e3307611b4ed8b20ca654f88 100644 (file)
--- a/hw/acpi/hmat.c
+++ b/hw/acpi/hmat.c
@@ -214,7 +214,7 @@ static void hmat_build_table_structs(GArray *table_data, NumaState *numa_state)
     }
 
     for (i = 0; i < numa_state->num_nodes; i++) {
-        if (numa_state->nodes[i].has_cpu) {
+        if (numa_state->nodes[i].has_cpu || numa_state->nodes[i].has_gi) {
             initiator_list[num_initiator++] = i;
         }
     }

diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 6a1bde61ce8c3580ce7c5f0244143b49d67d8ae8..c3ccfef026f4d60ad9bdfb73a2cde7b9feb8ebda 100644 (file)
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -57,6 +57,7 @@
 #include "migration/vmstate.h"
 #include "hw/acpi/ghes.h"
 #include "hw/acpi/viot.h"
+#include "hw/acpi/acpi_generic_initiator.h"
 #include "hw/virtio/virtio-acpi.h"
 #include "target/arm/multiprocessing.h"
 
@@ -504,6 +505,8 @@ build_srat(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
         }
     }
 
+    build_srat_generic_pci_initiator(table_data);
+
     if (ms->nvdimms_state->is_enabled) {
         nvdimm_build_srat(table_data);
     }

diff --git a/hw/core/numa.c b/hw/core/numa.c
index f08956ddb0ff794833213b1bbe98c7702871743d..58a32f1564914d7e5819ddc050b91c586a1e1d8b 100644 (file)
--- a/hw/core/numa.c
+++ b/hw/core/numa.c
@@ -229,7 +229,8 @@ void parse_numa_hmat_lb(NumaState *numa_state, NumaHmatLBOptions *node,
                    node->target, numa_state->num_nodes);
         return;
     }
-    if (!numa_info[node->initiator].has_cpu) {
+    if (!numa_info[node->initiator].has_cpu &&
+        !numa_info[node->initiator].has_gi) {
         error_setg(errp, "Invalid initiator=%d, it isn't an "
                    "initiator proximity domain", node->initiator);
         return;

diff --git a/include/hw/acpi/acpi_generic_initiator.h b/include/hw/acpi/acpi_generic_initiator.h
index 16de1d3d80a2f66783cf84f4dbe6000e1a99471d..a304bad73e0f703e701a473da243ac76f8ff6353 100644 (file)
--- a/include/hw/acpi/acpi_generic_initiator.h
+++ b/include/hw/acpi/acpi_generic_initiator.h
@@ -19,4 +19,29 @@ typedef struct AcpiGenericInitiator {
     uint16_t node;
 } AcpiGenericInitiator;
 
+/*
+ * ACPI 6.3:
+ * Table 5-81 Flags – Generic Initiator Affinity Structure
+ */
+typedef enum {
+    /*
+     * If clear, the OSPM ignores the contents of the Generic
+     * Initiator/Port Affinity Structure. This allows system firmware
+     * to populate the SRAT with a static number of structures, but only
+     * enable them as necessary.
+     */
+    GEN_AFFINITY_ENABLED = (1 << 0),
+} GenericAffinityFlags;
+
+/*
+ * ACPI 6.3:
+ * Table 5-80 Device Handle - PCI
+ */
+typedef struct PCIDeviceHandle {
+    uint16_t segment;
+    uint16_t bdf;
+} PCIDeviceHandle;
+
+void build_srat_generic_pci_initiator(GArray *table_data);
+
 #endif

diff --git a/include/sysemu/numa.h b/include/sysemu/numa.h
index 4173ef2afa75baba7cb2f03f861a1edc6f78bc87..825cfe86bc1a2d6c336441d6d62260079d7fbc63 100644 (file)
--- a/include/sysemu/numa.h
+++ b/include/sysemu/numa.h
@@ -41,6 +41,7 @@ struct NodeInfo {
     struct HostMemoryBackend *node_memdev;
     bool present;
     bool has_cpu;
+    bool has_gi;
     uint8_t lb_info_provided;
     uint16_t initiator;
     uint8_t distance[MAX_NODES];