lib_i386/video_bios.c

   1 /*
   2  * (C) Copyright 2002
   3  * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   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.
  12  *
  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.
  17  *
  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,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25 #include <pci.h>
  26 #include <malloc.h>
  27 #include <asm/ptrace.h>
  28 #include <asm/realmode.h>
  29 #include <asm/io.h>
  30 #include <asm/pci.h>
  31
  32 #undef PCI_BIOS_DEBUG
  33 #undef VGA_BIOS_DEBUG
  34
  35 #ifdef  VGA_BIOS_DEBUG
  36 #define PRINTF(fmt,args...)     printf (fmt ,##args)
  37 #else
  38 #define PRINTF(fmt,args...)
  39 #endif
  40
  41 #ifdef CONFIG_PCI
  42
  43 #ifdef PCI_BIOS_DEBUG
  44 #define RELOC_16(seg, off) *(u32*)(seg << 4 | (u32)&off)
  45 extern u32 num_pci_bios_present;
  46 extern u32 num_pci_bios_find_device;
  47 extern u32 num_pci_bios_find_class;
  48 extern u32 num_pci_bios_generate_special_cycle;
  49 extern u32 num_pci_bios_read_cfg_byte;
  50 extern u32 num_pci_bios_read_cfg_word;
  51 extern u32 num_pci_bios_read_cfg_dword;
  52 extern u32 num_pci_bios_write_cfg_byte;
  53 extern u32 num_pci_bios_write_cfg_word;
  54 extern u32 num_pci_bios_write_cfg_dword;
  55 extern u32 num_pci_bios_get_irq_routing;
  56 extern u32 num_pci_bios_set_irq;
  57 extern u32 num_pci_bios_unknown_function;
  58
  59 void print_bios_bios_stat(void)
  60 {
  61         printf("16 bit functions:\n");
  62         printf("pci_bios_present:                %d\n", RELOC_16(0xf000, num_pci_bios_present));
  63         printf("pci_bios_find_device:            %d\n", RELOC_16(0xf000, num_pci_bios_find_device));
  64         printf("pci_bios_find_class:             %d\n", RELOC_16(0xf000, num_pci_bios_find_class));
  65         printf("pci_bios_generate_special_cycle: %d\n", RELOC_16(0xf000, num_pci_bios_generate_special_cycle));
  66         printf("pci_bios_read_cfg_byte:          %d\n", RELOC_16(0xf000, num_pci_bios_read_cfg_byte));
  67         printf("pci_bios_read_cfg_word:          %d\n", RELOC_16(0xf000, num_pci_bios_read_cfg_word));
  68         printf("pci_bios_read_cfg_dword:         %d\n", RELOC_16(0xf000, num_pci_bios_read_cfg_dword));
  69         printf("pci_bios_write_cfg_byte:         %d\n", RELOC_16(0xf000, num_pci_bios_write_cfg_byte));
  70         printf("pci_bios_write_cfg_word:         %d\n", RELOC_16(0xf000, num_pci_bios_write_cfg_word));
  71         printf("pci_bios_write_cfg_dword:        %d\n", RELOC_16(0xf000, num_pci_bios_write_cfg_dword));
  72         printf("pci_bios_get_irq_routing:        %d\n", RELOC_16(0xf000, num_pci_bios_get_irq_routing));
  73         printf("pci_bios_set_irq:                %d\n", RELOC_16(0xf000, num_pci_bios_set_irq));
  74         printf("pci_bios_unknown_function:       %d\n", RELOC_16(0xf000, num_pci_bios_unknown_function));
  75
  76 }
  77 #endif
  78
  79 #define PCI_CLASS_VIDEO             3
  80 #define PCI_CLASS_VIDEO_STD         0
  81 #define PCI_CLASS_VIDEO_PROG_IF_VGA 0
  82
  83
  84 static u32 probe_pci_video(void)
  85 {
  86         pci_dev_t devbusfn;
  87
  88         if ((devbusfn = pci_find_class(PCI_CLASS_VIDEO,
  89                                        PCI_CLASS_VIDEO_STD,
  90                                        PCI_CLASS_VIDEO_PROG_IF_VGA, 0)) != -1) {
  91                 u32 old;
  92                 u32 addr;
  93
  94                 /* PCI video device detected */
  95                 printf("Found PCI VGA device at %02x.%02x.%x\n",
  96                        PCI_BUS(devbusfn), PCI_DEV(devbusfn), PCI_FUNC(devbusfn));
  97
  98                 /* Enable I/O decoding as well, PCI viudeo boards
  99                  * support I/O accesses, but they provide no
 100                  * bar register for this since the ports are fixed.
 101                  */
 102                 pci_write_config_word(devbusfn, PCI_COMMAND, PCI_COMMAND_MEMORY | PCI_COMMAND_IO | PCI_COMMAND_MASTER);
 103
 104                 /* Test the ROM decoder, do the device support a rom? */
 105                 pci_read_config_dword(devbusfn, PCI_ROM_ADDRESS, &old);
 106                 pci_write_config_dword(devbusfn, PCI_ROM_ADDRESS, PCI_ROM_ADDRESS_MASK);
 107                 pci_read_config_dword(devbusfn, PCI_ROM_ADDRESS, &addr);
 108                 pci_write_config_dword(devbusfn, PCI_ROM_ADDRESS, old);
 109
 110                 if (!addr) {
 111                         printf("PCI VGA have no ROM?\n");
 112                         return 0;
 113                 }
 114
 115                 /* device have a rom */
 116                 if (pci_shadow_rom(devbusfn, (void*)0xc0000)) {
 117                         printf("Shadowing of PCI VGA BIOS failed\n");
 118                         return 0;
 119                 }
 120
 121                 /* Now enable lagacy VGA port access */
 122                 if (pci_enable_legacy_video_ports(pci_bus_to_hose(PCI_BUS(devbusfn)))) {
 123                         printf("PCI VGA enable failed\n");
 124                         return 0;
 125                 }
 126
 127
 128                 /* return the pci device info, that we'll need later */
 129                 return PCI_BUS(devbusfn) << 8 |
 130                         PCI_DEV(devbusfn) << 3 | (PCI_FUNC(devbusfn)&7);
 131         }
 132
 133         return 0;
 134 }
 135
 136
 137 #endif
 138
 139 static int probe_isa_video(void)
 140 {
 141         u32 ptr;
 142         char *buf;
 143
 144         if (0 == (ptr = isa_map_rom(0xc0000, 0x8000))) {
 145                 return -1;
 146         }
 147         if (NULL == (buf=malloc(0x8000))) {
 148                 isa_unmap_rom(ptr);
 149                 return -1;
 150         }
 151         if (readw(ptr) != 0xaa55) {
 152                 free(buf);
 153                 isa_unmap_rom(ptr);
 154                 return -1;
 155         }
 156
 157         /* shadow the rom */
 158         memcpy(buf, (void*)ptr, 0x8000);
 159         isa_unmap_rom(ptr);
 160         memcpy((void*)0xc0000, buf, 0x8000);
 161
 162         free(buf);
 163
 164         return 0;
 165 }
 166
 167 int video_bios_init(void)
 168 {
 169         struct pt_regs regs;
 170
 171         /* clear the video bios area in case we warmbooted */
 172         memset((void*)0xc0000, 0, 0x8000);
 173         memset(&regs, 0, sizeof(struct pt_regs));
 174
 175         if (probe_isa_video()) {
 176                 /* No ISA board found, try the PCI bus */
 177                 regs.eax = probe_pci_video();
 178         }
 179
 180         /* Did we succeed in mapping any video bios */
 181         if (readw(0xc0000) == 0xaa55) {
 182                 int size;
 183                 int i;
 184                 u8 sum;
 185
 186                 PRINTF("Found video bios signature\n");
 187                 size = 512*readb(0xc0002);
 188                 PRINTF("size %d\n", size);
 189                 sum=0;
 190                 for (i=0;i<size;i++) {
 191                         sum += readb(0xc0000 + i);
 192                 }
 193                 PRINTF("Checksum is %sOK\n",sum?"NOT ":"");
 194                 if (sum) {
 195                         return 1;
 196                 }
 197
 198                 /* some video bioses (ATI Mach64) seem to think that
 199                  * the original int 10 handler is always at
 200                  * 0xf000:0xf065 , place an iret instruction there
 201                  */
 202                 writeb(0xcf, 0xff065);
 203
 204                 regs.esp = 0x8000;
 205                 regs.xss = 0x2000;
 206                 enter_realmode(0xc000, 3, &regs, &regs);
 207                 PRINTF("INT 0x10 vector after:  %04x:%04x\n",
 208                        readw(0x42), readw(0x40));
 209                 PRINTF("BIOS returned %scarry\n", regs.eflags & 1?"":"NOT ");
 210 #ifdef PCI_BIOS_DEBUG
 211                 print_bios_bios_stat();
 212 #endif
 213                 return (regs.eflags & 1);
 214
 215         }
 216
 217         return 1;
 218
 219 }