xref: /openbmc/qemu/hw/xen/xen_pt_load_rom.c (revision ba632924)
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,
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     Object *owner = OBJECT(dev);
33 
34     /* If loading ROM from file, pci handles it */
35     if (dev->romfile || !dev->rom_bar) {
36         return NULL;
37     }
38 
39     snprintf(rom_file, sizeof(rom_file),
40              "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/rom",
41              domain, bus, slot, function);
42 
43     /* Write "1" to the ROM file to enable it */
44     fp = fopen(rom_file, "r+");
45     if (fp == NULL) {
46         if (errno != ENOENT) {
47             error_report("pci-assign: Cannot open %s: %s", rom_file, strerror(errno));
48         }
49         return NULL;
50     }
51     if (fstat(fileno(fp), &st) == -1) {
52         error_report("pci-assign: Cannot stat %s: %s", rom_file, strerror(errno));
53         goto close_rom;
54     }
55 
56     val = 1;
57     if (fwrite(&val, 1, 1, fp) != 1) {
58         goto close_rom;
59     }
60     fseek(fp, 0, SEEK_SET);
61 
62     snprintf(name, sizeof(name), "%s.rom", object_get_typename(owner));
63     memory_region_init_ram(&dev->rom, owner, name, st.st_size, &error_abort);
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