xref: /openbmc/qemu/hw/xen/xen_pt_graphics.c (revision 9884abee)
1 /*
2  * graphics passthrough
3  */
4 #include "qemu/osdep.h"
5 #include "xen_pt.h"
6 #include "xen-host-pci-device.h"
7 #include "hw/xen/xen_backend.h"
8 
9 static unsigned long igd_guest_opregion;
10 static unsigned long igd_host_opregion;
11 
12 #define XEN_PCI_INTEL_OPREGION_MASK 0xfff
13 
14 typedef struct VGARegion {
15     int type;           /* Memory or port I/O */
16     uint64_t guest_base_addr;
17     uint64_t machine_base_addr;
18     uint64_t size;    /* size of the region */
19     int rc;
20 } VGARegion;
21 
22 #define IORESOURCE_IO           0x00000100
23 #define IORESOURCE_MEM          0x00000200
24 
25 static struct VGARegion vga_args[] = {
26     {
27         .type = IORESOURCE_IO,
28         .guest_base_addr = 0x3B0,
29         .machine_base_addr = 0x3B0,
30         .size = 0xC,
31         .rc = -1,
32     },
33     {
34         .type = IORESOURCE_IO,
35         .guest_base_addr = 0x3C0,
36         .machine_base_addr = 0x3C0,
37         .size = 0x20,
38         .rc = -1,
39     },
40     {
41         .type = IORESOURCE_MEM,
42         .guest_base_addr = 0xa0000 >> XC_PAGE_SHIFT,
43         .machine_base_addr = 0xa0000 >> XC_PAGE_SHIFT,
44         .size = 0x20,
45         .rc = -1,
46     },
47 };
48 
49 /*
50  * register VGA resources for the domain with assigned gfx
51  */
52 int xen_pt_register_vga_regions(XenHostPCIDevice *dev)
53 {
54     int i = 0;
55 
56     if (!is_igd_vga_passthrough(dev)) {
57         return 0;
58     }
59 
60     for (i = 0 ; i < ARRAY_SIZE(vga_args); i++) {
61         if (vga_args[i].type == IORESOURCE_IO) {
62             vga_args[i].rc = xc_domain_ioport_mapping(xen_xc, xen_domid,
63                             vga_args[i].guest_base_addr,
64                             vga_args[i].machine_base_addr,
65                             vga_args[i].size, DPCI_ADD_MAPPING);
66         } else {
67             vga_args[i].rc = xc_domain_memory_mapping(xen_xc, xen_domid,
68                             vga_args[i].guest_base_addr,
69                             vga_args[i].machine_base_addr,
70                             vga_args[i].size, DPCI_ADD_MAPPING);
71         }
72 
73         if (vga_args[i].rc) {
74             XEN_PT_ERR(NULL, "VGA %s mapping failed! (rc: %i)\n",
75                     vga_args[i].type == IORESOURCE_IO ? "ioport" : "memory",
76                     vga_args[i].rc);
77             return vga_args[i].rc;
78         }
79     }
80 
81     return 0;
82 }
83 
84 /*
85  * unregister VGA resources for the domain with assigned gfx
86  */
87 int xen_pt_unregister_vga_regions(XenHostPCIDevice *dev)
88 {
89     int i = 0;
90     int ret = 0;
91 
92     if (!is_igd_vga_passthrough(dev)) {
93         return 0;
94     }
95 
96     for (i = 0 ; i < ARRAY_SIZE(vga_args); i++) {
97         if (vga_args[i].type == IORESOURCE_IO) {
98             vga_args[i].rc = xc_domain_ioport_mapping(xen_xc, xen_domid,
99                             vga_args[i].guest_base_addr,
100                             vga_args[i].machine_base_addr,
101                             vga_args[i].size, DPCI_REMOVE_MAPPING);
102         } else {
103             vga_args[i].rc = xc_domain_memory_mapping(xen_xc, xen_domid,
104                             vga_args[i].guest_base_addr,
105                             vga_args[i].machine_base_addr,
106                             vga_args[i].size, DPCI_REMOVE_MAPPING);
107         }
108 
109         if (vga_args[i].rc) {
110             XEN_PT_ERR(NULL, "VGA %s unmapping failed! (rc: %i)\n",
111                     vga_args[i].type == IORESOURCE_IO ? "ioport" : "memory",
112                     vga_args[i].rc);
113             return vga_args[i].rc;
114         }
115     }
116 
117     if (igd_guest_opregion) {
118         ret = xc_domain_memory_mapping(xen_xc, xen_domid,
119                 (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT),
120                 (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
121                 3,
122                 DPCI_REMOVE_MAPPING);
123         if (ret) {
124             return ret;
125         }
126     }
127 
128     return 0;
129 }
130 
131 static void *get_vgabios(XenPCIPassthroughState *s, int *size,
132                        XenHostPCIDevice *dev)
133 {
134     return pci_assign_dev_load_option_rom(&s->dev, OBJECT(&s->dev), size,
135                                           dev->domain, dev->bus,
136                                           dev->dev, dev->func);
137 }
138 
139 /* Refer to Seabios. */
140 struct rom_header {
141     uint16_t signature;
142     uint8_t size;
143     uint8_t initVector[4];
144     uint8_t reserved[17];
145     uint16_t pcioffset;
146     uint16_t pnpoffset;
147 } __attribute__((packed));
148 
149 struct pci_data {
150     uint32_t signature;
151     uint16_t vendor;
152     uint16_t device;
153     uint16_t vitaldata;
154     uint16_t dlen;
155     uint8_t drevision;
156     uint8_t class_lo;
157     uint16_t class_hi;
158     uint16_t ilen;
159     uint16_t irevision;
160     uint8_t type;
161     uint8_t indicator;
162     uint16_t reserved;
163 } __attribute__((packed));
164 
165 void xen_pt_setup_vga(XenPCIPassthroughState *s, XenHostPCIDevice *dev,
166                      Error **errp)
167 {
168     unsigned char *bios = NULL;
169     struct rom_header *rom;
170     int bios_size;
171     char *c = NULL;
172     char checksum = 0;
173     uint32_t len = 0;
174     struct pci_data *pd = NULL;
175 
176     if (!is_igd_vga_passthrough(dev)) {
177         error_setg(errp, "Need to enable igd-passthrough");
178         return;
179     }
180 
181     bios = get_vgabios(s, &bios_size, dev);
182     if (!bios) {
183         error_setg(errp, "VGA: Can't get VBIOS");
184         return;
185     }
186 
187     /* Currently we fixed this address as a primary. */
188     rom = (struct rom_header *)bios;
189     pd = (void *)(bios + (unsigned char)rom->pcioffset);
190 
191     /* We may need to fixup Device Identification. */
192     if (pd->device != s->real_device.device_id) {
193         pd->device = s->real_device.device_id;
194 
195         len = rom->size * 512;
196         /* Then adjust the bios checksum */
197         for (c = (char *)bios; c < ((char *)bios + len); c++) {
198             checksum += *c;
199         }
200         if (checksum) {
201             bios[len - 1] -= checksum;
202             XEN_PT_LOG(&s->dev, "vga bios checksum is adjusted %x!\n",
203                        checksum);
204         }
205     }
206 
207     /* Currently we fixed this address as a primary for legacy BIOS. */
208     cpu_physical_memory_rw(0xc0000, bios, bios_size, 1);
209 }
210 
211 uint32_t igd_read_opregion(XenPCIPassthroughState *s)
212 {
213     uint32_t val = 0;
214 
215     if (!igd_guest_opregion) {
216         return val;
217     }
218 
219     val = igd_guest_opregion;
220 
221     XEN_PT_LOG(&s->dev, "Read opregion val=%x\n", val);
222     return val;
223 }
224 
225 #define XEN_PCI_INTEL_OPREGION_PAGES 0x3
226 #define XEN_PCI_INTEL_OPREGION_ENABLE_ACCESSED 0x1
227 void igd_write_opregion(XenPCIPassthroughState *s, uint32_t val)
228 {
229     int ret;
230 
231     if (igd_guest_opregion) {
232         XEN_PT_LOG(&s->dev, "opregion register already been set, ignoring %x\n",
233                    val);
234         return;
235     }
236 
237     /* We just work with LE. */
238     xen_host_pci_get_block(&s->real_device, XEN_PCI_INTEL_OPREGION,
239             (uint8_t *)&igd_host_opregion, 4);
240     igd_guest_opregion = (unsigned long)(val & ~XEN_PCI_INTEL_OPREGION_MASK)
241                             | (igd_host_opregion & XEN_PCI_INTEL_OPREGION_MASK);
242 
243     ret = xc_domain_iomem_permission(xen_xc, xen_domid,
244             (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
245             XEN_PCI_INTEL_OPREGION_PAGES,
246             XEN_PCI_INTEL_OPREGION_ENABLE_ACCESSED);
247 
248     if (ret) {
249         XEN_PT_ERR(&s->dev, "[%d]:Can't enable to access IGD host opregion:"
250                     " 0x%lx.\n", ret,
251                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT)),
252         igd_guest_opregion = 0;
253         return;
254     }
255 
256     ret = xc_domain_memory_mapping(xen_xc, xen_domid,
257             (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT),
258             (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
259             XEN_PCI_INTEL_OPREGION_PAGES,
260             DPCI_ADD_MAPPING);
261 
262     if (ret) {
263         XEN_PT_ERR(&s->dev, "[%d]:Can't map IGD host opregion:0x%lx to"
264                     " guest opregion:0x%lx.\n", ret,
265                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
266                     (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT));
267         igd_guest_opregion = 0;
268         return;
269     }
270 
271     XEN_PT_LOG(&s->dev, "Map OpRegion: 0x%lx -> 0x%lx\n",
272                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
273                     (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT));
274 }
275