1 /* 2 * ACPI Virtual I/O Translation table implementation 3 * 4 * SPDX-License-Identifier: GPL-2.0-or-later 5 */ 6 #include "qemu/osdep.h" 7 #include "hw/acpi/acpi.h" 8 #include "hw/acpi/aml-build.h" 9 #include "hw/acpi/viot.h" 10 #include "hw/pci/pci.h" 11 #include "hw/pci/pci_host.h" 12 13 struct viot_pci_host_range { 14 int min_bus; 15 int max_bus; 16 }; 17 18 static void build_pci_host_range(GArray *table_data, int min_bus, int max_bus, 19 uint16_t output_node) 20 { 21 /* Type */ 22 build_append_int_noprefix(table_data, 1 /* PCI range */, 1); 23 /* Reserved */ 24 build_append_int_noprefix(table_data, 0, 1); 25 /* Length */ 26 build_append_int_noprefix(table_data, 24, 2); 27 /* Endpoint start */ 28 build_append_int_noprefix(table_data, PCI_BUILD_BDF(min_bus, 0), 4); 29 /* PCI Segment start */ 30 build_append_int_noprefix(table_data, 0, 2); 31 /* PCI Segment end */ 32 build_append_int_noprefix(table_data, 0, 2); 33 /* PCI BDF start */ 34 build_append_int_noprefix(table_data, PCI_BUILD_BDF(min_bus, 0), 2); 35 /* PCI BDF end */ 36 build_append_int_noprefix(table_data, PCI_BUILD_BDF(max_bus, 0xff), 2); 37 /* Output node */ 38 build_append_int_noprefix(table_data, output_node, 2); 39 /* Reserved */ 40 build_append_int_noprefix(table_data, 0, 6); 41 } 42 43 /* Build PCI range for a given PCI host bridge */ 44 static int enumerate_pci_host_bridges(Object *obj, void *opaque) 45 { 46 GArray *pci_host_ranges = opaque; 47 48 if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) { 49 PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus; 50 51 if (bus && !pci_bus_bypass_iommu(bus)) { 52 int min_bus, max_bus; 53 54 pci_bus_range(bus, &min_bus, &max_bus); 55 56 const struct viot_pci_host_range pci_host_range = { 57 .min_bus = min_bus, 58 .max_bus = max_bus, 59 }; 60 g_array_append_val(pci_host_ranges, pci_host_range); 61 } 62 } 63 64 return 0; 65 } 66 67 static gint pci_host_range_compare(gconstpointer a, gconstpointer b) 68 { 69 struct viot_pci_host_range *range_a = (struct viot_pci_host_range *)a; 70 struct viot_pci_host_range *range_b = (struct viot_pci_host_range *)b; 71 72 if (range_a->min_bus < range_b->min_bus) { 73 return -1; 74 } else if (range_a->min_bus > range_b->min_bus) { 75 return 1; 76 } else { 77 return 0; 78 } 79 } 80 81 /* 82 * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI 83 * endpoints. 84 * 85 * Defined in the ACPI Specification (Version TBD) 86 */ 87 void build_viot(MachineState *ms, GArray *table_data, BIOSLinker *linker, 88 uint16_t virtio_iommu_bdf, const char *oem_id, 89 const char *oem_table_id) 90 { 91 /* The virtio-iommu node follows the 48-bytes header */ 92 int viommu_off = 48; 93 AcpiTable table = { .sig = "VIOT", .rev = 0, 94 .oem_id = oem_id, .oem_table_id = oem_table_id }; 95 GArray *pci_host_ranges = g_array_new(false, true, 96 sizeof(struct viot_pci_host_range)); 97 struct viot_pci_host_range *pci_host_range; 98 int i; 99 100 /* Build the list of PCI ranges that this viommu manages */ 101 object_child_foreach_recursive(OBJECT(ms), enumerate_pci_host_bridges, 102 pci_host_ranges); 103 104 /* Sort the pci host ranges by min_bus */ 105 g_array_sort(pci_host_ranges, pci_host_range_compare); 106 107 /* ACPI table header */ 108 acpi_table_begin(&table, table_data); 109 /* Node count */ 110 build_append_int_noprefix(table_data, pci_host_ranges->len + 1, 2); 111 /* Node offset */ 112 build_append_int_noprefix(table_data, viommu_off, 2); 113 /* Reserved */ 114 build_append_int_noprefix(table_data, 0, 8); 115 116 /* Virtio-iommu node */ 117 /* Type */ 118 build_append_int_noprefix(table_data, 3 /* virtio-pci IOMMU */, 1); 119 /* Reserved */ 120 build_append_int_noprefix(table_data, 0, 1); 121 /* Length */ 122 build_append_int_noprefix(table_data, 16, 2); 123 /* PCI Segment */ 124 build_append_int_noprefix(table_data, 0, 2); 125 /* PCI BDF number */ 126 build_append_int_noprefix(table_data, virtio_iommu_bdf, 2); 127 /* Reserved */ 128 build_append_int_noprefix(table_data, 0, 8); 129 130 /* PCI ranges found above */ 131 for (i = 0; i < pci_host_ranges->len; i++) { 132 pci_host_range = &g_array_index(pci_host_ranges, 133 struct viot_pci_host_range, i); 134 135 build_pci_host_range(table_data, pci_host_range->min_bus, 136 pci_host_range->max_bus, viommu_off); 137 } 138 139 g_array_free(pci_host_ranges, true); 140 141 acpi_table_end(linker, &table); 142 } 143 144