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.
182 " movl $0x1000, %eax \n"
183 " movl %eax, %esp \n"
185 /* Load our 16 it idt */
190 /* Dump zeros in the other segregs */
198 /* run VGA BIOS at 0xc000:0003 */
199 " lcall $0xc000, $0x0003\n"
201 /* if we got here, just about done.
202 * Need to get back to protected mode */
203 " movl %cr0, %eax \n"
204 " orl $0x0000001, %eax\n" /* PE = 1 */
205 " movl %eax, %cr0 \n"
207 /* Now that we are in protected mode jump to a 32 bit code segment. */
208 " data32 ljmp $0x10, $vgarestart\n"
211 " movw $0x18, %ax \n"
218 /* restore proper gdt and idt */
219 " lgdt %cs:gdtarg \n"
224 " mov __stack, %esp \n"
229 __asm__ (".text\n""real_mode_switch_end:\n");
230 extern char real_mode_switch_end[];
232 /* call vga bios int 10 function 0x4f14 to enable main console
233 epia-m does not always autosence the main console so forcing it on is good !! */
234 void vga_enable_console()
236 __asm__ __volatile__ (
237 /* paranoia -- does ecx get saved? not sure. This is
238 * the easiest safe thing to do. */
241 " mov %esp, __stack \n"
244 " lgdt %cs:__mygdtaddr \n"
246 /* This configures CS properly for real mode. */
247 " ljmp $0x28, $__vga_ec_16bit\n"
250 /* 16 bit code from here on... */
252 /* Load the segment registers w/ properly configured segment
253 * descriptors. They will retain these configurations (limits,
254 * writability, etc.) once protected mode is turned off. */
262 /* Turn off protection (bit 0 in CR0) */
263 " movl %cr0, %eax \n"
264 " andl $0xFFFFFFFE, %eax\n"
265 " movl %eax, %cr0 \n"
267 /* Now really going into real mode */
268 " ljmp $0, $__vga_ec_real \n"
271 /* put the stack at the end of page zero.
272 * that way we can easily share it between real and protected,
273 * since the 16-bit ESP at segment 0 will work for any case.
277 " movl $0x1000, %eax \n"
278 " movl %eax, %esp \n"
280 /* debugging for RGM */
282 " outb %al, $0x80 \n"
284 /* Load our 16 it idt */
289 /* Dump zeros in the other segregs */
295 /* ask bios to enable main console */
296 /* set up for int 10 call - values found from X server
297 * bios call routines */
298 " movw $0x4f14,%ax \n"
299 " movw $0x8003,%bx \n"
305 " movb $0x55, %al \n"
306 " outb %al, $0x80 \n"
308 /* if we got here, just about done.
309 * Need to get back to protected mode */
310 " movl %cr0, %eax \n"
311 " orl $0x0000001, %eax\n" /* PE = 1 */
312 " movl %eax, %cr0 \n"
314 /* Now that we are in protected mode jump to a 32 bit code segment. */
315 " data32 ljmp $0x10, $vga_ec_restart\n"
318 " movw $0x18, %ax \n"
325 /* restore proper gdt and idt */
326 " lgdt %cs:gdtarg \n"
328 " .globl vga__ec_exit \n"
330 " mov __stack, %esp \n"
335 void do_vgabios(void)
338 unsigned long busdevfn;
341 unsigned int size = 64*1024;
344 /* clear vga bios data area */
345 for (i = 0x400; i < 0x500; i++) {
346 *(unsigned char *) i = 0;
349 dev = dev_find_class(PCI_CLASS_DISPLAY_VGA<<8 , 0);
352 printk(BIOS_DEBUG, "NO VGA FOUND\n");
355 printk(BIOS_DEBUG, "found VGA: vid=%x, did=%x\n", dev->vendor, dev->device);
357 /* declare rom address here - keep any config data out of the way
358 * of core LXB stuff */
360 rom = (u32)cbfs_load_optionrom(dev->vendor, dev->device, 0);
361 pci_write_config32(dev, PCI_ROM_ADDRESS, rom|1);
362 printk(BIOS_DEBUG, "VGA BIOS ROM base address: %x\n", rom);
364 buf = (unsigned char *) rom;
365 if ((buf[0] == 0x55) && (buf[1] == 0xaa)) {
366 memcpy((void *) 0xc0000, buf, size);
368 write_protect_vgabios(); // in northbridge
370 // check signature again
371 buf = (unsigned char *) 0xc0000;
372 if (buf[0]==0x55 && buf[1]==0xAA) {
373 busdevfn = (dev->bus->secondary << 8) | dev->path.pci.devfn;
374 printk(BIOS_DEBUG, "bus/devfn = %#lx\n", busdevfn);
376 real_mode_switch_call_vga(busdevfn);
378 printk(BIOS_DEBUG, "Failed to copy VGA BIOS to 0xc0000\n");
380 printk(BIOS_DEBUG, "BAD SIGNATURE 0x%x 0x%x\n", buf[0], buf[1]);
382 pci_write_config32(dev, PCI_ROM_ADDRESS, 0);
386 // we had hoped to avoid this.
387 // this is a stub IDT only. It's main purpose is to ignore calls
389 // no longer. Dammit. We have to respond to these.
391 unsigned short offset, cs;
394 // from a handy writeup that andrey found.
397 // There are some assumptions we can make here.
398 // First, the Top Of Stack (TOS) is located on the top of page zero.
399 // we can share this stack between real and protected mode.
400 // that simplifies a lot of things ...
401 // we'll just push all the registers on the stack as longwords,
402 // and pop to protected mode.
403 // second, since this only ever runs as part of coreboot,
404 // we know all the segment register values -- so we don't save any.
405 // keep the handler that calls things small. It can do a call to
406 // more complex code in coreboot itself. This helps a lot as we don't
407 // have to do address fixup in this little stub, and calls are absolute
408 // so the handler is relocatable.
411 __asm__ __volatile__ (
416 " ljmp $0, $callbiosint16\n"
422 void debughandler(void)
424 __asm__ __volatile__ (
433 "end_debughandle: \n"
438 // Calling conventions. The first C function is called with this stuff
439 // on the stack. They look like value parameters, but note that if you
440 // modify them they will go back to the INTx function modified.
441 // the C function will call the biosint function with these as
442 // REFERENCE parameters. In this way, we can easily get
443 // returns back to the INTx caller (i.e. vgabios)
444 void callbiosint(void)
446 __asm__ __volatile__ (
453 // clean up the int #. To save space we put it in the lower
454 // byte. But the top 24 bits are junk.
455 " andl $0xff, %eax\n"
456 // this push does two things:
457 // - put the INT # on the stack as a parameter
458 // - provides us with a temp for the %cr0 mods.
461 " orl $0x00000001, %eax\n" /* PE = 1 */
463 /* Now that we are in protected mode jump to a 32 bit code segment. */
464 " data32 ljmp $0x10, $biosprotect\n"
467 " movw $0x18, %ax \n"
475 // back to real mode ...
476 " ljmp $0x28, $__rms_16bit2\n"
479 /* 16 bit code from here on... */
480 /* Load the segment registers w/ properly configured segment
481 * descriptors. They will retain these configurations (limits,
482 * writability, etc.) once protected mode is turned off. */
490 /* Turn off protection (bit 0 in CR0) */
491 " movl %cr0, %eax \n"
492 " andl $0xFFFFFFFE, %eax \n"
493 " movl %eax, %cr0 \n"
495 /* Now really going into real mode */
496 " ljmp $0, $__rms_real2 \n"
500 * FixME: where is esp? */
504 /* ebugging for RGM */
506 " outb %al, $0x80 \n"
508 /* Load our 16 it idt */
513 /* Dump zeros in the other segregs */
520 /* pop the INT # that you pushed earlier */
537 int pcibios(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
538 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
539 unsigned long *pecx, unsigned long *peax, unsigned long *pflags);
541 int handleint21(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
542 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
543 unsigned long *pecx, unsigned long *peax, unsigned long *pflags
546 extern void vga_exit(void);
548 int biosint(unsigned long intnumber,
549 unsigned long gsfs, unsigned long dses,
550 unsigned long edi, unsigned long esi,
551 unsigned long ebp, unsigned long esp,
552 unsigned long ebx, unsigned long edx,
553 unsigned long ecx, unsigned long eax,
554 unsigned long cs_ip, unsigned short stackflags)
565 printk(BIOS_DEBUG, "biosint: INT# 0x%lx\n", intnumber);
566 printk(BIOS_DEBUG, "biosint: eax 0x%lx ebx 0x%lx ecx 0x%lx edx 0x%lx\n",
568 printk(BIOS_DEBUG, "biosint: ebp 0x%lx esp 0x%lx edi 0x%lx esi 0x%lx\n",
570 printk(BIOS_DEBUG, "biosint: ip 0x%lx cs 0x%lx flags 0x%lx\n",
573 // cases in a good compiler are just as good as your own tables.
576 // These are not BIOS service, but the CPU-generated exceptions
577 printk(BIOS_INFO, "biosint: Oops, exception %lu\n", intnumber);
579 printk(BIOS_DEBUG, "Stack contents: ");
580 while (esp < 0x1000) {
581 printk(BIOS_DEBUG, "0x%04x ", *(unsigned short *) esp);
584 printk(BIOS_DEBUG, "\n");
586 printk(BIOS_DEBUG, "biosint: Bailing out\n");
592 ret = pcibios( &edi, &esi, &ebp, &esp,
593 &ebx, &edx, &ecx, &eax, &flags);
601 ret=handleint21( &edi, &esi, &ebp, &esp,
602 &ebx, &edx, &ecx, &eax, &flags);
605 printk(BIOS_INFO, "BIOSINT: Unsupport int #0x%lx\n", intnumber);
609 flags |= 1; // carry flags
617 void setup_realmode_idt(void)
619 extern unsigned char idthandle, end_idthandle;
620 extern unsigned char debughandle, end_debughandle;
623 struct realidt *idts = (struct realidt *) 0;
624 int codesize = &end_idthandle - &idthandle;
625 unsigned char *intbyte, *codeptr;
627 // for each int, we create a customized little handler
628 // that just pushes %ax, puts the int # in %al,
629 // then calls the common interrupt handler.
630 // this necessitated because intel didn't know much about
631 // architecture when they did the 8086 (it shows)
632 // (hmm do they know anymore even now :-)
633 // obviously you can see I don't really care about memory
634 // efficiency. If I did I would probe back through the stack
635 // and get it that way. But that's really disgusting.
636 for (i = 0; i < 256; i++) {
638 codeptr = (char*) 4096 + i * codesize;
639 idts[i].offset = (unsigned) codeptr;
640 memcpy(codeptr, &idthandle, codesize);
641 intbyte = codeptr + 3;
645 // fixed entry points
647 // VGA BIOSes tend to hardcode f000:f065 as the previous handler of
649 // calling convention here is the same as INTs, we can reuse
650 // the int entry code.
651 codeptr = (char*) 0xff065;
652 memcpy(codeptr, &idthandle, codesize);
653 intbyte = codeptr + 3;
654 *intbyte = 0x42; /* int42 is the relocated int10 */
656 /* debug handler - useful to set a programmable delay between instructions if the
657 TF bit is set upon call to real mode */
659 idts[1].offset = 16384;
660 memcpy(16384, &debughandle, &end_debughandle - &debughandle);
670 READCONFBYTE = 0xb108,
671 READCONFWORD = 0xb109,
672 READCONFDWORD = 0xb10a,
673 WRITECONFBYTE = 0xb10b,
674 WRITECONFWORD = 0xb10c,
675 WRITECONFDWORD = 0xb10d
678 // errors go in AH. Just set these up so that word assigns
681 PCIBIOS_NODEV = 0x8600,
682 PCIBIOS_BADREG = 0x8700
686 pcibios(unsigned long *pedi, unsigned long *pesi, unsigned long *pebp,
687 unsigned long *pesp, unsigned long *pebx, unsigned long *pedx,
688 unsigned long *pecx, unsigned long *peax, unsigned long *pflags)
690 unsigned long edi = *pedi;
691 unsigned long esi = *pesi;
692 unsigned long ebp = *pebp;
693 unsigned long esp = *pesp;
694 unsigned long ebx = *pebx;
695 unsigned long edx = *pedx;
696 unsigned long ecx = *pecx;
697 unsigned long eax = *peax;
698 unsigned long flags = *pflags;
699 unsigned short func = (unsigned short) eax;
701 unsigned short devid, vendorid, devfn;
702 short devindex; /* Use short to get rid of garbage in upper half of 32-bit register */
718 while ((dev = dev_find_device(vendorid, devid, dev))) {
724 unsigned short busdevfn;
726 // busnum is an unsigned char;
727 // devfn is an int, so we mask it off.
728 busdevfn = (dev->bus->secondary << 8)
729 | (dev->path.pci.devfn & 0xff);
730 printk(BIOS_DEBUG, "0x%x: return 0x%x\n", func, busdevfn);
734 *peax = PCIBIOS_NODEV;
751 devfn = *pebx & 0xff;
754 dev = dev_find_slot(bus, devfn);
756 printk(BIOS_DEBUG, "0x%x: BAD DEVICE bus %d devfn 0x%x\n", func, bus, devfn);
757 // idiots. the pcibios guys assumed you'd never pass a bad bus/devfn!
758 *peax = PCIBIOS_BADREG;
763 byte = pci_read_config8(dev, reg);
767 word = pci_read_config16(dev, reg);
771 dword = pci_read_config32(dev, reg);
776 pci_write_config8(dev, reg, byte);
780 pci_write_config16(dev, reg, word);
784 pci_write_config32(dev, reg, dword);
789 retval = PCIBIOS_BADREG;
790 printk(BIOS_DEBUG, "0x%x: bus %d devfn 0x%x reg 0x%x val 0x%lx\n",
791 func, bus, devfn, reg, *pecx);
797 printk(BIOS_ERR, "UNSUPPORTED PCIBIOS FUNCTION 0x%x\n", func);
804 int handleint21(unsigned long *edi, unsigned long *esi, unsigned long *ebp,
805 unsigned long *esp, unsigned long *ebx, unsigned long *edx,
806 unsigned long *ecx, unsigned long *eax, unsigned long *flags)
815 *ebx=0x545; // MCLK = 133, 32M frame buffer, 256 M main memory
824 *ecx = (*ecx & 0xffffff00 ) | 2; // panel type = 2 = 1024 * 768
829 *ebx= (*ebx & 0xffff0000) | 2;
830 *ecx= (*ecx & 0xffff0000) | 0x401; // PAL + crt only
831 *edx= (*edx & 0xffff0000) | 0; // TV Layout - default