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
build_pci_host_range(GArray * table_data,int min_bus,int max_bus,uint16_t output_node)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 */
enumerate_pci_host_bridges(Object * obj,void * opaque)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
pci_host_range_compare(gconstpointer a,gconstpointer b)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 */
build_viot(MachineState * ms,GArray * table_data,BIOSLinker * linker,uint16_t virtio_iommu_bdf,const char * oem_id,const char * oem_table_id)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