hw/acpi: Generic Port Affinity Structure support

These are very similar to the recently added Generic Initiators
but instead of representing an initiator of memory traffic they
represent an edge point beyond which may lie either targets or
initiators.  Here we add these ports such that they may
be targets of hmat_lb records to describe the latency and
bandwidth from host side initiators to the port.  A discoverable
mechanism such as UEFI CDAT read from CXL devices and switches
is used to discover the remainder of the path, and the OS can build
up full latency and bandwidth numbers as need for work and data
placement decisions.

Acked-by: Markus Armbruster <armbru@redhat.com>
Tested-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20240916174122.1843197-1-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 115 insertions, 1 deletions

diff --git a/hw/acpi/pci.c b/hw/acpi/pci.c
index 3e1db161cc..d7a0e91f01 100644
--- a/hw/acpi/pci.c
+++ b/hw/acpi/pci.c
@@ -30,6 +30,7 @@
 #include "hw/boards.h"
 #include "hw/acpi/aml-build.h"
 #include "hw/acpi/pci.h"
+#include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_device.h"
 #include "hw/pci/pcie_host.h"
 
@@ -177,9 +178,122 @@ static int build_acpi_generic_initiator(Object *obj, void *opaque)
     return 0;
 }
 
-void build_srat_generic_pci_initiator(GArray *table_data)
+typedef struct AcpiGenericPort {
+    /* private */
+    Object parent;
+
+    /* public */
+    char *pci_bus;
+    uint32_t node;
+} AcpiGenericPort;
+
+typedef struct AcpiGenericPortClass {
+    ObjectClass parent_class;
+} AcpiGenericPortClass;
+
+#define TYPE_ACPI_GENERIC_PORT "acpi-generic-port"
+
+OBJECT_DEFINE_TYPE_WITH_INTERFACES(AcpiGenericPort, acpi_generic_port,
+                   ACPI_GENERIC_PORT, OBJECT,
+                   { TYPE_USER_CREATABLE },
+                   { NULL })
+
+OBJECT_DECLARE_SIMPLE_TYPE(AcpiGenericPort, ACPI_GENERIC_PORT)
+
+static void acpi_generic_port_init(Object *obj)
+{
+    AcpiGenericPort *gp = ACPI_GENERIC_PORT(obj);
+
+    gp->node = MAX_NODES;
+    gp->pci_bus = NULL;
+}
+
+static void acpi_generic_port_finalize(Object *obj)
+{
+    AcpiGenericPort *gp = ACPI_GENERIC_PORT(obj);
+
+    g_free(gp->pci_bus);
+}
+
+static void acpi_generic_port_set_pci_bus(Object *obj, const char *val,
+                                          Error **errp)
+{
+    AcpiGenericPort *gp = ACPI_GENERIC_PORT(obj);
+
+    gp->pci_bus = g_strdup(val);
+}
+
+static void acpi_generic_port_set_node(Object *obj, Visitor *v,
+                                       const char *name, void *opaque,
+                                       Error **errp)
+{
+    AcpiGenericPort *gp = ACPI_GENERIC_PORT(obj);
+    uint32_t value;
+
+    if (!visit_type_uint32(v, name, &value, errp)) {
+        return;
+    }
+
+    if (value >= MAX_NODES) {
+        error_printf("%s: Invalid NUMA node specified\n",
+                     TYPE_ACPI_GENERIC_INITIATOR);
+        exit(1);
+    }
+
+    gp->node = value;
+}
+
+static void acpi_generic_port_class_init(ObjectClass *oc, void *data)
+{
+    object_class_property_add_str(oc, "pci-bus", NULL,
+        acpi_generic_port_set_pci_bus);
+    object_class_property_set_description(oc, "pci-bus",
+       "PCI Bus of the host bridge associated with this GP affinity structure");
+    object_class_property_add(oc, "node", "int", NULL,
+        acpi_generic_port_set_node, NULL, NULL);
+    object_class_property_set_description(oc, "node",
+       "The NUMA node like ID to index HMAT/SLIT NUMA properties involving GP");
+}
+
+static int build_acpi_generic_port(Object *obj, void *opaque)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    const char *hid = "ACPI0016";
+    GArray *table_data = opaque;
+    AcpiGenericPort *gp;
+    uint32_t uid;
+    Object *o;
+
+    if (!object_dynamic_cast(obj, TYPE_ACPI_GENERIC_PORT)) {
+        return 0;
+    }
+
+    gp = ACPI_GENERIC_PORT(obj);
+
+    if (gp->node >= ms->numa_state->num_nodes) {
+        error_printf("%s: node %d is invalid.\n",
+                     TYPE_ACPI_GENERIC_PORT, gp->node);
+        exit(1);
+    }
+
+    o = object_resolve_path_type(gp->pci_bus, TYPE_PXB_CXL_BUS, NULL);
+    if (!o) {
+        error_printf("%s: device must be a CXL host bridge.\n",
+                     TYPE_ACPI_GENERIC_PORT);
+       exit(1);
+    }
+
+    uid = object_property_get_uint(o, "acpi_uid", &error_fatal);
+    build_srat_acpi_generic_port(table_data, gp->node, hid, uid);
+
+    return 0;
+}
+
+void build_srat_generic_affinity_structures(GArray *table_data)
 {
     object_child_foreach_recursive(object_get_root(),
                                    build_acpi_generic_initiator,
                                    table_data);
+    object_child_foreach_recursive(object_get_root(), build_acpi_generic_port,
+                                   table_data);
 }