1 #include <console/console.h>
2 #include <device/pci.h>
3 #include <device/pci_ids.h>
4 #include <device/pci_ops.h>
12 /* vgabios.c. Derived from: */
14 /*------------------------------------------------------------ -*- C -*-
15 * 2 Kernel Monte a.k.a. Linux loading Linux on x86
17 * Erik Arjan Hendriks <hendriks@lanl.gov>
19 * This version is a derivative of the original two kernel monte
20 * which is (C) 2000 Scyld.
22 * Copyright (C) 2000 Scyld Computing Corporation
24 * This program is free software; you can redistribute it and/or modify
25 * it under the terms of the GNU General Public License as published by
26 * the Free Software Foundation; either version 2 of the License, or
27 * (at your option) any later version.
29 * This program is distributed in the hope that it will be useful,
30 * but WITHOUT ANY WARRANTY; without even the implied warranty of
31 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
32 * GNU General Public License for more details.
34 * You should have received a copy of the GNU General Public License
35 * along with this program; if not, write to the Free Software
36 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
38 * Portions related to the alpha architecture are:
40 * Copyright(C) 2001 University of California. LA-CC Number 01-67.
41 * This software has been authored by an employee or employees of the
42 * University of California, operator of the Los Alamos National
43 * Laboratory under Contract No. W-7405-ENG-36 with the U.S.
44 * Department of Energy. The U.S. Government has rights to use,
45 * reproduce, and distribute this software. If the software is
46 * modified to produce derivative works, such modified software should
47 * be clearly marked, so as not to confuse it with the version
48 * available from LANL.
50 * This software may be used and distributed according to the terms
51 * of the GNU General Public License, incorporated herein by
52 * reference to http://www.gnu.org/licenses/gpl.html.
54 * This software is provided by the author(s) "as is" and any express
55 * or implied warranties, including, but not limited to, the implied
56 * warranties of merchantability and fitness for a particular purpose
57 * are disclaimed. In no event shall the author(s) be liable for any
58 * direct, indirect, incidental, special, exemplary, or consequential
59 * damages (including, but not limited to, procurement of substitute
60 * goods or services; loss of use, data, or profits; or business
61 * interruption) however caused and on any theory of liability,
62 * whether in contract, strict liability, or tort (including
63 * negligence or otherwise) arising in any way out of the use of this
64 * software, even if advised of the possibility of such damage.
66 * $Id: vgabios.c,v 1.5 2004/10/06 17:33:52 rminnich Exp $
67 *--------------------------------------------------------------------*/
69 /* Modified to be a self sufficient plug in so that it can be used
70 without reliance on other parts of coreboot's core
71 (C) 2005 Nick.Barker9@btinternet.com
73 Used initially for epia-m where there are problems getting the bios
74 emulator to successfully run this bios.
77 /* Declare a temporary global descriptor table - necessary because the
78 Core part of the bios no longer sets up any 16 bit segments */
80 /* pointer to original gdt */
85 /* compute the table limit */
86 "__mygdt_limit = __mygdt_end - __mygdt - 1 \n"
89 " .word __mygdt_limit \n"
93 /* selgdt 0, unused */
94 " .word 0x0000, 0x0000 \n"
95 " .byte 0x00, 0x00, 0x00, 0x00 \n"
97 /* selgdt 8, unused */
98 " .word 0x0000, 0x0000 \n"
99 " .byte 0x00, 0x00, 0x00, 0x00 \n"
101 /* selgdt 0x10, flat code segment */
102 " .word 0xffff, 0x0000 \n"
103 " .byte 0x00, 0x9b, 0xcf, 0x00 \n"
105 /* selgdt 0x18, flat data segment */
106 " .word 0xffff, 0x0000 \n"
107 " .byte 0x00, 0x93, 0xcf, 0x00 \n"
109 /* selgdt 0x20, unused */
110 " .word 0x0000, 0x0000 \n"
111 " .byte 0x00, 0x00, 0x00, 0x00 \n"
113 /* selgdt 0x28 16-bit 64k code at 0x00000000 */
114 " .word 0xffff, 0x0000 \n"
115 " .byte 0, 0x9a, 0, 0 \n"
117 /* selgdt 0x30 16-bit 64k data at 0x00000000 */
118 " .word 0xffff, 0x0000 \n"
119 " .byte 0, 0x92, 0, 0 \n"
124 /* Declare a pointer to where our idt is going to be i.e. at mem zero */
125 __asm__ ("__myidt: \n"
133 /* The address arguments to this function are PHYSICAL ADDRESSES */
134 static void real_mode_switch_call_vga(unsigned long devfn)
136 __asm__ __volatile__ (
137 // paranoia -- does ecx get saved? not sure. This is
138 // the easiest safe thing to do.
141 " mov %esp, __stack \n"
143 "__stack: .long 0 \n"
145 /* get devfn into %ecx */
146 " movl %esp, %ebp \n"
147 " movl 8(%ebp), %ecx \n"
149 " lgdt %cs:__mygdtaddr \n"
151 /* This configures CS properly for real mode. */
152 " ljmp $0x28, $__rms_16bit\n"
155 /* 16 bit code from here on... */
157 /* Load the segment registers w/ properly configured segment
158 * descriptors. They will retain these configurations (limits,
159 * writability, etc.) once protected mode is turned off. */
167 /* Turn off protection (bit 0 in CR0) */
168 " movl %cr0, %eax \n"
169 " andl $0xFFFFFFFE, %eax \n"
170 " movl %eax, %cr0 \n"
172 /* Now really going into real mode */
173 " ljmp $0, $__rms_real\n"
176 /* put the stack at the end of page zero.
177 * that way we can easily share it between real and protected,
178 * since the 16-bit ESP at segment 0 will work for any case.
183 " movl $0x1000, %eax \n"
184 " movl %eax, %esp \n"
186 /* Load our 16 it idt */
191 /* Dump zeros in the other segregs */
199 /* run VGA BIOS at 0xc000:0003 */
200 " lcall $0xc000, $0x0003\n"
202 /* if we got here, just about done.
203 * Need to get back to protected mode */
204 " movl %cr0, %eax \n"
205 " orl $0x0000001, %eax\n" /* PE = 1 */
206 " movl %eax, %cr0 \n"
208 /* Now that we are in protected mode jump to a 32 bit code segment. */
209 " data32 ljmp $0x10, $vgarestart\n"
212 " movw $0x18, %ax \n"
219 /* restore proper gdt and idt */
220 " lgdt %cs:gdtarg \n"
225 " mov __stack, %esp \n"
230 __asm__ (".text\n""real_mode_switch_end:\n");
231 extern char real_mode_switch_end[];
233 /* call vga bios int 10 function 0x4f14 to enable main console
234 epia-m does not always autosence the main console so forcing it on is good !! */
235 void vga_enable_console()
237 __asm__ __volatile__ (
238 /* paranoia -- does ecx get saved? not sure. This is
239 * the easiest safe thing to do. */
242 " mov %esp, __stack \n"
245 " lgdt %cs:__mygdtaddr \n"
247 /* This configures CS properly for real mode. */
248 " ljmp $0x28, $__vga_ec_16bit\n"
251 /* 16 bit code from here on... */
253 /* Load the segment registers w/ properly configured segment
254 * descriptors. They will retain these configurations (limits,
255 * writability, etc.) once protected mode is turned off. */
263 /* Turn off protection (bit 0 in CR0) */
264 " movl %cr0, %eax \n"
265 " andl $0xFFFFFFFE, %eax\n"
266 " movl %eax, %cr0 \n"
268 /* Now really going into real mode */
269 " ljmp $0, $__vga_ec_real \n"
272 /* put the stack at the end of page zero.
273 * that way we can easily share it between real and protected,
274 * since the 16-bit ESP at segment 0 will work for any case.
279 " movl $0x1000, %eax \n"
280 " movl %eax, %esp \n"
282 /* debugging for RGM */
284 " outb %al, $0x80 \n"
286 /* Load our 16 it idt */
291 /* Dump zeros in the other segregs */
297 /* ask bios to enable main console */
298 /* set up for int 10 call - values found from X server
299 * bios call routines */
300 " movw $0x4f14,%ax \n"
301 " movw $0x8003,%bx \n"
307 " movb $0x55, %al \n"
308 " outb %al, $0x80 \n"
310 /* if we got here, just about done.
311 * Need to get back to protected mode */
312 " movl %cr0, %eax \n"
313 " orl $0x0000001, %eax\n" /* PE = 1 */
314 " movl %eax, %cr0 \n"
316 /* Now that we are in protected mode jump to a 32 bit code segment. */
317 " data32 ljmp $0x10, $vga_ec_restart\n"
320 " movw $0x18, %ax \n"
327 /* restore proper gdt and idt */
328 " lgdt %cs:gdtarg \n"
330 " .globl vga__ec_exit \n"
332 " mov __stack, %esp \n"
337 void do_vgabios(void)
340 unsigned long busdevfn;
343 unsigned int size = 64*1024;
346 /* clear vga bios data area */
347 for (i = 0x400; i < 0x500; i++) {
348 *(unsigned char *) i = 0;
351 dev = dev_find_class(PCI_CLASS_DISPLAY_VGA<<8 , 0);
354 printk(BIOS_DEBUG, "NO VGA FOUND\n");
357 printk(BIOS_DEBUG, "found VGA: vid=%x, did=%x\n", dev->vendor, dev->device);
359 /* declare rom address here - keep any config data out of the way
360 * of core LXB stuff */
362 rom = cbfs_load_optionrom(dev->vendor, dev->device, NULL);
363 pci_write_config32(dev, PCI_ROM_ADDRESS, (u32)rom | 1);
364 printk(BIOS_DEBUG, "rom base: %p\n", rom);
366 buf = (unsigned char *) rom;
367 if ((buf[0] == 0x55) && (buf[1] == 0xaa)) {
368 memcpy((void *) 0xc0000, buf, size);
370 write_protect_vgabios(); // in northbridge
372 // check signature again
373 buf = (unsigned char *) 0xc0000;
374 if (buf[0]==0x55 && buf[1]==0xAA) {
375 busdevfn = (dev->bus->secondary << 8) | dev->path.pci.devfn;
376 printk(BIOS_DEBUG, "bus/devfn = %#lx\n", busdevfn);
378 real_mode_switch_call_vga(busdevfn);
380 printk(BIOS_DEBUG, "Failed to copy VGA BIOS to 0xc0000\n");
382 printk(BIOS_DEBUG, "BAD SIGNATURE 0x%x 0x%x\n", buf[0], buf[1]);
384 pci_write_config32(dev, PCI_ROM_ADDRESS, 0);
388 // we had hoped to avoid this.
389 // this is a stub IDT only. It's main purpose is to ignore calls
391 // no longer. Dammit. We have to respond to these.
393 unsigned short offset, cs;
396 // from a handy writeup that andrey found.
399 // There are some assumptions we can make here.
400 // First, the Top Of Stack (TOS) is located on the top of page zero.
401 // we can share this stack between real and protected mode.
402 // that simplifies a lot of things ...
403 // we'll just push all the registers on the stack as longwords,
404 // and pop to protected mode.
405 // second, since this only ever runs as part of coreboot,
406 // we know all the segment register values -- so we don't save any.
407 // keep the handler that calls things small. It can do a call to
408 // more complex code in coreboot itself. This helps a lot as we don't
409 // have to do address fixup in this little stub, and calls are absolute
410 // so the handler is relocatable.
413 __asm__ __volatile__ (
418 " ljmp $0, $callbiosint16\n"
424 void debughandler(void)
426 __asm__ __volatile__ (
435 "end_debughandle: \n"
440 // Calling conventions. The first C function is called with this stuff
441 // on the stack. They look like value parameters, but note that if you
442 // modify them they will go back to the INTx function modified.
443 // the C function will call the biosint function with these as
444 // REFERENCE parameters. In this way, we can easily get
445 // returns back to the INTx caller (i.e. vgabios)
446 void callbiosint(void)
448 __asm__ __volatile__ (
455 // clean up the int #. To save space we put it in the lower
456 // byte. But the top 24 bits are junk.
457 " andl $0xff, %eax\n"
458 // this push does two things:
459 // - put the INT # on the stack as a parameter
460 // - provides us with a temp for the %cr0 mods.
463 " orl $0x00000001, %eax\n" /* PE = 1 */
465 /* Now that we are in protected mode jump to a 32 bit code segment. */
466 " data32 ljmp $0x10, $biosprotect\n"
469 " movw $0x18, %ax \n"
477 // back to real mode ...
478 " ljmp $0x28, $__rms_16bit2\n"
481 /* 16 bit code from here on... */
482 /* Load the segment registers w/ properly configured segment
483 * descriptors. They will retain these configurations (limits,
484 * writability, etc.) once protected mode is turned off. */
492 /* Turn off protection (bit 0 in CR0) */
493 " movl %cr0, %eax \n"
494 " andl $0xFFFFFFFE, %eax \n"
495 " movl %eax, %cr0 \n"
497 /* Now really going into real mode */
498 " ljmp $0, $__rms_real2 \n"
502 * FixME: where is esp? */
506 /* ebugging for RGM */
508 " outb %al, $0x80 \n"
510 /* Load our 16 it idt */
515 /* Dump zeros in the other segregs */
522 /* pop the INT # that you pushed earlier */
539 int pcibios(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
540 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
541 unsigned long *pecx, unsigned long *peax, unsigned long *pflags);
543 int handleint21(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
544 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
545 unsigned long *pecx, unsigned long *peax, unsigned long *pflags
548 extern void vga_exit(void);
550 int biosint(unsigned long intnumber,
551 unsigned long gsfs, unsigned long dses,
552 unsigned long edi, unsigned long esi,
553 unsigned long ebp, unsigned long esp,
554 unsigned long ebx, unsigned long edx,
555 unsigned long ecx, unsigned long eax,
556 unsigned long cs_ip, unsigned short stackflags)
567 printk(BIOS_DEBUG, "biosint: INT# 0x%lx\n", intnumber);
568 printk(BIOS_DEBUG, "biosint: eax 0x%lx ebx 0x%lx ecx 0x%lx edx 0x%lx\n",
570 printk(BIOS_DEBUG, "biosint: ebp 0x%lx esp 0x%lx edi 0x%lx esi 0x%lx\n",
572 printk(BIOS_DEBUG, "biosint: ip 0x%lx cs 0x%lx flags 0x%lx\n",
575 // cases in a good compiler are just as good as your own tables.
578 // These are not BIOS service, but the CPU-generated exceptions
579 printk(BIOS_INFO, "biosint: Oops, exception %lu\n", intnumber);
581 printk(BIOS_DEBUG, "Stack contents: ");
582 while (esp < 0x1000) {
583 printk(BIOS_DEBUG, "0x%04x ", *(unsigned short *) esp);
586 printk(BIOS_DEBUG, "\n");
588 printk(BIOS_DEBUG, "biosint: Bailing out\n");
594 ret = pcibios( &edi, &esi, &ebp, &esp,
595 &ebx, &edx, &ecx, &eax, &flags);
603 ret=handleint21( &edi, &esi, &ebp, &esp,
604 &ebx, &edx, &ecx, &eax, &flags);
607 printk(BIOS_INFO, "BIOSINT: Unsupport int #0x%lx\n", intnumber);
611 flags |= 1; // carry flags
619 void setup_realmode_idt(void)
621 extern unsigned char idthandle, end_idthandle;
622 extern unsigned char debughandle, end_debughandle;
625 struct realidt *idts = (struct realidt *) 0;
626 int codesize = &end_idthandle - &idthandle;
627 unsigned char *intbyte, *codeptr;
629 // for each int, we create a customized little handler
630 // that just pushes %ax, puts the int # in %al,
631 // then calls the common interrupt handler.
632 // this necessitated because intel didn't know much about
633 // architecture when they did the 8086 (it shows)
634 // (hmm do they know anymore even now :-)
635 // obviously you can see I don't really care about memory
636 // efficiency. If I did I would probe back through the stack
637 // and get it that way. But that's really disgusting.
638 for (i = 0; i < 256; i++) {
640 codeptr = (unsigned char*) 4096 + i * codesize;
641 idts[i].offset = (unsigned) codeptr;
642 memcpy(codeptr, &idthandle, codesize);
643 intbyte = codeptr + 3;
647 // fixed entry points
649 // VGA BIOSes tend to hardcode f000:f065 as the previous handler of
651 // calling convention here is the same as INTs, we can reuse
652 // the int entry code.
653 codeptr = (unsigned char*) 0xff065;
654 memcpy(codeptr, &idthandle, codesize);
655 intbyte = codeptr + 3;
656 *intbyte = 0x42; /* int42 is the relocated int10 */
658 /* debug handler - useful to set a programmable delay between instructions if the
659 TF bit is set upon call to real mode */
661 idts[1].offset = 16384;
662 memcpy((void *)16384, &debughandle, &end_debughandle - &debughandle);
672 READCONFBYTE = 0xb108,
673 READCONFWORD = 0xb109,
674 READCONFDWORD = 0xb10a,
675 WRITECONFBYTE = 0xb10b,
676 WRITECONFWORD = 0xb10c,
677 WRITECONFDWORD = 0xb10d
680 // errors go in AH. Just set these up so that word assigns
683 PCIBIOS_NODEV = 0x8600,
684 PCIBIOS_BADREG = 0x8700
688 pcibios(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
689 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
690 unsigned long *pecx, unsigned long *peax, unsigned long *pflags)
692 unsigned short func = (unsigned short) (*peax);
694 unsigned short devid, vendorid, devfn;
695 short devindex; /* Use short to get rid of garbage in upper half of 32-bit register */
711 while ((dev = dev_find_device(vendorid, devid, dev))) {
717 unsigned short busdevfn;
719 // busnum is an unsigned char;
720 // devfn is an int, so we mask it off.
721 busdevfn = (dev->bus->secondary << 8)
722 | (dev->path.pci.devfn & 0xff);
723 printk(BIOS_DEBUG, "0x%x: return 0x%x\n", func, busdevfn);
727 *peax = PCIBIOS_NODEV;
744 devfn = *pebx & 0xff;
747 dev = dev_find_slot(bus, devfn);
749 printk(BIOS_DEBUG, "0x%x: BAD DEVICE bus %d devfn 0x%x\n", func, bus, devfn);
750 // idiots. the pcibios guys assumed you'd never pass a bad bus/devfn!
751 *peax = PCIBIOS_BADREG;
756 byte = pci_read_config8(dev, reg);
760 word = pci_read_config16(dev, reg);
764 dword = pci_read_config32(dev, reg);
769 pci_write_config8(dev, reg, byte);
773 pci_write_config16(dev, reg, word);
777 pci_write_config32(dev, reg, dword);
782 retval = PCIBIOS_BADREG;
783 printk(BIOS_DEBUG, "0x%x: bus %d devfn 0x%x reg 0x%x val 0x%lx\n",
784 func, bus, devfn, reg, *pecx);
790 printk(BIOS_ERR, "UNSUPPORTED PCIBIOS FUNCTION 0x%x\n", func);
797 int handleint21(unsigned long *edi, unsigned long *esi, unsigned long *ebp,
798 unsigned long *esp, unsigned long *ebx, unsigned long *edx,
799 unsigned long *ecx, unsigned long *eax, unsigned long *flags)
808 *ebx=0x545; // MCLK = 133, 32M frame buffer, 256 M main memory
817 *ecx = (*ecx & 0xffffff00 ) | 2; // panel type = 2 = 1024 * 768
822 *ebx= (*ebx & 0xffff0000) | 2;
823 *ecx= (*ecx & 0xffff0000) | 0x401; // PAL + crt only
824 *edx= (*edx & 0xffff0000) | 0; // TV Layout - default