3 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 #include <asm/ptrace.h>
28 #include <asm/realmode.h>
37 #define PRINTF(fmt, args...) printf(fmt, ##args)
39 #define PRINTF(fmt, args...)
42 #define PCI_CLASS_VIDEO 3
43 #define PCI_CLASS_VIDEO_STD 0
44 #define PCI_CLASS_VIDEO_PROG_IF_VGA 0
46 DEFINE_PCI_DEVICE_TABLE(supported) = {
47 {PCI_VIDEO_VENDOR_ID, PCI_VIDEO_DEVICE_ID},
51 static u32 probe_pci_video(void)
53 struct pci_controller *hose;
54 pci_dev_t devbusfn = pci_find_devices(supported, 0);
56 if ((devbusfn != -1)) {
60 /* PCI video device detected */
61 printf("Found PCI VGA device at %02x.%02x.%x\n",
66 /* Enable I/O decoding as well, PCI viudeo boards
67 * support I/O accesses, but they provide no
68 * bar register for this since the ports are fixed.
70 pci_write_config_word(devbusfn,
76 /* Test the ROM decoder, do the device support a rom? */
77 pci_read_config_dword(devbusfn, PCI_ROM_ADDRESS, &old);
78 pci_write_config_dword(devbusfn, PCI_ROM_ADDRESS,
79 (u32)PCI_ROM_ADDRESS_MASK);
80 pci_read_config_dword(devbusfn, PCI_ROM_ADDRESS, &addr);
81 pci_write_config_dword(devbusfn, PCI_ROM_ADDRESS, old);
84 printf("PCI VGA have no ROM?\n");
88 /* device have a rom */
89 if (pci_shadow_rom(devbusfn, (void *)0xc0000)) {
90 printf("Shadowing of PCI VGA BIOS failed\n");
94 /* Now enable lagacy VGA port access */
95 hose = pci_bus_to_hose(PCI_BUS(devbusfn));
96 if (pci_enable_legacy_video_ports(hose)) {
97 printf("PCI VGA enable failed\n");
102 /* return the pci device info, that we'll need later */
103 return PCI_BUS(devbusfn) << 8 |
104 PCI_DEV(devbusfn) << 3 | (PCI_FUNC(devbusfn) & 7);
110 static int probe_isa_video(void)
115 ptr = isa_map_rom(0xc0000, 0x8000);
120 buf = malloc(0x8000);
126 if (readw(ptr) != 0xaa55) {
133 memcpy(buf, (void *)ptr, 0x8000);
135 memcpy((void *)0xc0000, buf, 0x8000);
142 int video_bios_init(void)
149 /* clear the video bios area in case we warmbooted */
150 memset((void *)0xc0000, 0, 0x8000);
151 memset(®s, 0, sizeof(struct pt_regs));
153 if (probe_isa_video())
154 /* No ISA board found, try the PCI bus */
155 regs.eax = probe_pci_video();
157 /* Did we succeed in mapping any video bios */
158 if (readw(0xc0000) == 0xaa55) {
159 PRINTF("Found video bios signature\n");
160 size = readb(0xc0002) * 512;
161 PRINTF("size %d\n", size);
164 for (i = 0; i < size; i++)
165 sum += readb(0xc0000 + i);
167 PRINTF("Checksum is %sOK\n", sum ? "NOT " : "");
173 * Some video bioses (ATI Mach64) seem to think that
174 * the original int 10 handler is always at
175 * 0xf000:0xf065 , place an iret instruction there
177 writeb(0xcf, 0xff065);
181 enter_realmode(0xc000, 3, ®s, ®s);
183 PRINTF("INT 0x10 vector after: %04x:%04x\n",
184 readw(0x42), readw(0x40));
185 PRINTF("BIOS returned %scarry\n",
186 regs.eflags & 0x00000001 ? "" : "NOT ");
187 #ifdef PCI_BIOS_DEBUG
188 print_bios_bios_stat();
190 return regs.eflags & 0x00000001;