xref: /openbmc/qemu/hw/xen/xen_pt_load_rom.c (revision 8d8cb956)
1 /*
2  * This is splited from hw/i386/kvm/pci-assign.c
3  */
4 #include "qemu/osdep.h"
5 #include "qapi/error.h"
6 #include "hw/hw.h"
7 #include "hw/i386/pc.h"
8 #include "qemu/error-report.h"
9 #include "ui/console.h"
10 #include "hw/loader.h"
11 #include "monitor/monitor.h"
12 #include "qemu/range.h"
13 #include "sysemu/sysemu.h"
14 #include "hw/pci/pci.h"
15 #include "xen_pt.h"
16 
17 /*
18  * Scan the assigned devices for the devices that have an option ROM, and then
19  * load the corresponding ROM data to RAM. If an error occurs while loading an
20  * option ROM, we just ignore that option ROM and continue with the next one.
21  */
22 void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner,
23                                      int *size, unsigned int domain,
24                                      unsigned int bus, unsigned int slot,
25                                      unsigned int function)
26 {
27     char name[32], rom_file[64];
28     FILE *fp;
29     uint8_t val;
30     struct stat st;
31     void *ptr = NULL;
32 
33     /* If loading ROM from file, pci handles it */
34     if (dev->romfile || !dev->rom_bar) {
35         return NULL;
36     }
37 
38     snprintf(rom_file, sizeof(rom_file),
39              "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/rom",
40              domain, bus, slot, function);
41 
42     /* Write "1" to the ROM file to enable it */
43     fp = fopen(rom_file, "r+");
44     if (fp == NULL) {
45         if (errno != ENOENT) {
46             error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno));
47         }
48         return NULL;
49     }
50     if (fstat(fileno(fp), &st) == -1) {
51         error_report("pci-assign: Cannot stat %s: %s", rom_file, strerror(errno));
52         goto close_rom;
53     }
54 
55     val = 1;
56     if (fwrite(&val, 1, 1, fp) != 1) {
57         goto close_rom;
58     }
59     fseek(fp, 0, SEEK_SET);
60 
61     snprintf(name, sizeof(name), "%s.rom", object_get_typename(owner));
62     memory_region_init_ram_nomigrate(&dev->rom, owner, name, st.st_size, &error_abort);
63     vmstate_register_ram(&dev->rom, &dev->qdev);
64     ptr = memory_region_get_ram_ptr(&dev->rom);
65     memset(ptr, 0xff, st.st_size);
66 
67     if (!fread(ptr, 1, st.st_size, fp)) {
68         error_report("pci-assign: Cannot read from host %s", rom_file);
69         error_printf("Device option ROM contents are probably invalid "
70                      "(check dmesg).\nSkip option ROM probe with rombar=0, "
71                      "or load from file with romfile=\n");
72         goto close_rom;
73     }
74 
75     pci_register_bar(dev, PCI_ROM_SLOT, 0, &dev->rom);
76     dev->has_rom = true;
77     *size = st.st_size;
78 close_rom:
79     /* Write "0" to disable ROM */
80     fseek(fp, 0, SEEK_SET);
81     val = 0;
82     if (!fwrite(&val, 1, 1, fp)) {
83         XEN_PT_WARN(dev, "%s\n", "Failed to disable pci-sysfs rom file");
84     }
85     fclose(fp);
86 
87     return ptr;
88 }
89