diff options
Diffstat (limited to 'src/pc80')
| -rw-r--r-- | src/pc80/Config.lb | 4 | ||||
| -rw-r--r-- | src/pc80/vgabios.c | 618 | ||||
| -rw-r--r-- | src/pc80/vgachip.h | 10 |
3 files changed, 632 insertions, 0 deletions
diff --git a/src/pc80/Config.lb b/src/pc80/Config.lb index f04ada0e42..3aa425604d 100644 --- a/src/pc80/Config.lb +++ b/src/pc80/Config.lb @@ -18,3 +18,7 @@ end if CONFIG_KEYBOARD object keyboard.o end + +if CONFIG_LEGACY_VGABIOS + object vgabios.o +end diff --git a/src/pc80/vgabios.c b/src/pc80/vgabios.c new file mode 100644 index 0000000000..05e3ce33ed --- /dev/null +++ b/src/pc80/vgabios.c @@ -0,0 +1,618 @@ +#include <pci.h> +#include <pci_ids.h> +#undef __KERNEL__ +#include <arch/io.h> +#include <printk.h> +#include <string.h> +#include "vgachip.h" + +/* vgabios.c. Derived from: */ + +/*------------------------------------------------------------ -*- C -*- + * 2 Kernel Monte a.k.a. Linux loading Linux on x86 + * + * Erik Arjan Hendriks <hendriks@lanl.gov> + * + * This version is a derivative of the original two kernel monte + * which is (C) 2000 Scyld. + * + * Copyright (C) 2000 Scyld Computing Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Portions related to the alpha architecture are: + * + * Copyright(C) 2001 University of California. LA-CC Number 01-67. + * This software has been authored by an employee or employees of the + * University of California, operator of the Los Alamos National + * Laboratory under Contract No. W-7405-ENG-36 with the U.S. + * Department of Energy. The U.S. Government has rights to use, + * reproduce, and distribute this software. If the software is + * modified to produce derivative works, such modified software should + * be clearly marked, so as not to confuse it with the version + * available from LANL. + * + * This software may be used and distributed according to the terms + * of the GNU General Public License, incorporated herein by + * reference to http://www.gnu.org/licenses/gpl.html. + * + * This software is provided by the author(s) "as is" and any express + * or implied warranties, including, but not limited to, the implied + * warranties of merchantability and fitness for a particular purpose + * are disclaimed. In no event shall the author(s) be liable for any + * direct, indirect, incidental, special, exemplary, or consequential + * damages (including, but not limited to, procurement of substitute + * goods or services; loss of use, data, or profits; or business + * interruption) however caused and on any theory of liability, + * whether in contract, strict liability, or tort (including + * negligence or otherwise) arising in any way out of the use of this + * software, even if advised of the possibility of such damage. + * + * $Id$ + *--------------------------------------------------------------------*/ + +/* The address arguments to this function are PHYSICAL ADDRESSES */ +static void real_mode_switch_call_vga(unsigned long devfn) +{ + __asm__ __volatile__ + ( + // paranoia -- does ecx get saved? not sure. This is + // the easiest safe thing to do. + "pushal\n" + /* save the stack */ + "mov %esp, __stack\n" + "jmp 1f\n" + "__stack: .long 0\n" + "1:\n" + /* get devfn into %ecx */ + "movl %esp, %ebp\n" + "movl 8(%ebp), %ecx\n" + /* This configures CS properly for real mode. */ + " ljmp $0x28, $__rms_16bit\n" + "__rms_16bit: \n" + ".code16 \n" /* 16 bit code from here on... */ + + /* Load the segment registers w/ properly configured segment + * descriptors. They will retain these configurations (limits, + * writability, etc.) once protected mode is turned off. */ + " mov $0x30, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + " mov %ax, %ss \n" + + /* Turn off protection (bit 0 in CR0) */ + " movl %cr0, %eax \n" + " andl $0xFFFFFFFE, %eax \n" + " movl %eax, %cr0 \n" + + /* Now really going into real mode */ + " ljmp $0, $__rms_real \n" + "__rms_real: \n" + + // put the stack at the end of page zero. + // that way we can easily share it between real and protected, + // since the 16-bit ESP at segment 0 will work for any case. + /* Setup a stack */ + " mov $0x0, %ax \n" + " mov %ax, %ss \n" + " movl $0x1000, %eax \n" + " movl %eax, %esp \n" + /* debugging for RGM */ + " mov $0x11, %al \n" + " outb %al, $0x80\n" + + /* Dump zeros in the other segregs */ + " xor %ax, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + " mov %cx, %ax \n" + " .byte 0x9a, 0x03, 0, 0, 0xc0 \n" + " movb $0x55, %al\noutb %al, $0x80\n" + /* if we got here, just about done. + * Need to get back to protected mode */ + "movl %cr0, %eax\n" + // "andl $0x7FFAFFD1, %eax\n" /* PG,AM,WP,NE,TS,EM,MP = 0 */ + // "orl $0x60000001, %eax\n" /* CD, NW, PE = 1 */ + "orl $0x0000001, %eax\n" /* PE = 1 */ + "movl %eax, %cr0\n" + /* Now that we are in protected mode jump to a 32 bit code segment. */ + "data32 ljmp $0x10, $vgarestart\n" + "vgarestart:\n" + ".code32\n" + " movw $0x18, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + " mov %ax, %ss \n" + ".globl vga_exit\n" + "vga_exit:\n" + " mov __stack, %esp\n" + " popal\n" + ); +} +__asm__ (".text\n""real_mode_switch_end:\n"); +extern char real_mode_switch_end[]; + +void +do_vgabios(void) +{ + struct pci_dev *dev; + unsigned long busdevfn; + unsigned int rom = 0; + unsigned char *buf; + unsigned int size = 64*1024; + int i; + + for (i=0x400; i<0x500; i++) { + printk_debug("%02x%c", *(unsigned char *)i, i%16==15 ? '\n' : ' '); + *(unsigned char *) i = 0; + } + + for (i=0x400; i<0x500; i++) { + printk_debug("%02x%c", *(unsigned char *)i, i%16==15 ? '\n' : ' '); + } + + dev = pci_find_class(PCI_CLASS_DISPLAY_VGA <<8, NULL); + + if (! dev) { + printk_debug("NO VGA FOUND\n"); + return; + } + printk_debug("found VGA: vid=%x, did=%x\n", dev->vendor, dev->device); + +#ifdef VGABIOS_START + // Use VGA BIOS blob at specified address + rom = VGABIOS_START; +#else + pci_read_config32(dev, PCI_ROM_ADDRESS, &rom); + // paranoia + rom = 0xf0000000; + pci_write_config32(dev, PCI_ROM_ADDRESS, rom|1); + printk_debug("rom base, size: %x\n", rom); +#endif + buf = (unsigned char *) rom; + if ((buf[0] == 0x55) && (buf[1] = 0xaa)) { + memcpy((void *) 0xc0000, buf, size); + + for(i = 0; i < 16; i++) + printk_debug("0x%x ", buf[i]); + // check signature here later! + busdevfn = (dev->bus->secondary << 8) | dev->devfn; + real_mode_switch_call_vga(busdevfn); + } else + printk_debug("BAD SIGNATURE 0x%x 0x%x\n", buf[0], buf[1]); +#ifndef VGABIOS_START + pci_write_config32(dev, PCI_ROM_ADDRESS, 0); +#endif +} + + +// we had hoped to avoid this. +// this is a stub IDT only. It's main purpose is to ignore calls +// to the BIOS. +// no longer. Dammit. We have to respond to these. +struct realidt { + unsigned short offset, cs; +}; + +// from a handy writeup that andrey found. + +// handler. +// There are some assumptions we can make here. +// First, the Top Of Stack (TOS) is located on the top of page zero. +// we can share this stack between real and protected mode. +// that simplifies a lot of things ... +// we'll just push all the registers on the stack as longwords, +// and pop to protected mode. +// second, since this only ever runs as part of linuxbios, +// we know all the segment register values -- so we don't save any. +// keep the handler that calls things small. It can do a call to +// more complex code in linuxbios itself. This helps a lot as we don't +// have to do address fixup in this little stub, and calls are absolute +// so the handler is relocatable. +void handler(void) { + __asm__ __volatile__ ( + ".code16\n" + "idthandle:\n" + " pushal\n" + " movb $0, %al\n" + " ljmp $0, $callbiosint16\n" + "end_idthandle:\n" + ".code32\n" + ); + +} + +// Calling conventions. The first C function is called with this stuff +// on the stack. They look like value parameters, but note that if you +// modify them they will go back to the INTx function modified. +// the C function will call the biosint function with these as +// REFERENCE parameters. In this way, we can easily get +// returns back to the INTx caller (i.e. vgabios) +void callbiosint(void) { + __asm__ __volatile__ ( + ".code16\n" + "callbiosint16:\n" + // clean up the int #. To save space we put it in the lower + // byte. But the top 24 bits are junk. + "andl $0xff, %eax\n" + // this push does two things: + // - put the INT # on the stack as a parameter + // - provides us with a temp for the %cr0 mods. + "pushl %eax\n" + "movl %cr0, %eax\n" + //"andl $0x7FFAFFD1, %eax\n" /* PG,AM,WP,NE,TS,EM,MP = 0 */ + //"orl $0x60000001, %eax\n" /* CD, NW, PE = 1 */ + "orl $0x00000001, %eax\n" /* PE = 1 */ + "movl %eax, %cr0\n" + /* Now that we are in protected mode jump to a 32 bit code segment. */ + "data32 ljmp $0x10, $biosprotect\n" + "biosprotect:\n" + ".code32\n" + " movw $0x18, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + " mov %ax, %ss \n" + " call biosint \n" + // back to real mode ... + " ljmp $0x28, $__rms_16bit\n" + "__rms_16bit: \n" + ".code16 \n" /* 16 bit code from here on... */ + + /* Load the segment registers w/ properly configured segment + * descriptors. They will retain these configurations (limits, + * writability, etc.) once protected mode is turned off. */ + " mov $0x30, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + " mov %ax, %ss \n" + + /* Turn off protection (bit 0 in CR0) */ + " movl %cr0, %eax \n" + " andl $0xFFFFFFFE, %eax \n" + " movl %eax, %cr0 \n" + + /* Now really going into real mode */ + " ljmp $0, $__rms_real \n" + "__rms_real: \n" + + /* Setup a stack */ + " mov $0x0, %ax \n" + " mov %ax, %ss \n" + /* ebugging for RGM */ + " mov $0x11, %al \n" + " outb %al, $0x80\n" + " xor %ax, %ax \n" + " mov %ax, %ds \n" + " mov %ax, %es \n" + " mov %ax, %fs \n" + " mov %ax, %gs \n" + // pop the INT # that you pushed earlier + " popl %eax\n" + " popal\n" + " iret\n" + ".code32\n" + ); +} + + +enum { + PCIBIOS = 0x1a, + MEMSIZE = 0x12 +}; +int +pcibios( + unsigned long *pedi, + unsigned long *pesi, + unsigned long *pebp, + unsigned long *pesp, + unsigned long *pebx, + unsigned long *pedx, + unsigned long *pecx, + unsigned long *peax, + unsigned long *pflags + ); + +extern void vga_exit(void); + +int +biosint( + unsigned long intnumber, + unsigned long edi, + unsigned long esi, + unsigned long ebp, + unsigned long esp, + unsigned long ebx, + unsigned long edx, + unsigned long ecx, + unsigned long eax, + unsigned long cs_ip, + unsigned short stackflags + ) { + unsigned long ip; + unsigned long cs; + unsigned long flags; + int ret = -1; + + ip = cs_ip & 0xffff; + cs = cs_ip >> 16; + flags = stackflags; + + printk_debug("biosint: # 0x%lx, eax 0x%lx ebx 0x%lx ecx 0x%lx edx 0x%lx\n", + intnumber, eax, ebx, ecx, edx); + printk_debug("biosint: ebp 0x%lx esp 0x%lx edi 0x%lx esi 0x%lx\n", ebp, esp, edi, esi); + printk_debug("biosint: ip 0x%x cs 0x%x flags 0x%x\n", ip, cs, flags); + // cases in a good compiler are just as good as your own tables. + switch (intnumber) { + case 0 ... 15: + // These are not BIOS service, but the CPU-generated exceptions + printk_info("biosint: Oops, exception %u\n", intnumber); + if (esp < 0x1000) { + printk_debug("Stack contents: "); + while (esp < 0x1000) { + printk_debug("0x%04x ", *(unsigned short *) esp); + esp += 2; + } + printk_debug("\n"); + } + printk_debug("biosint: Bailing out\n"); + // "longjmp" + vga_exit(); + break; + + case PCIBIOS: + ret = pcibios( &edi, &esi, &ebp, &esp, + &ebx, &edx, &ecx, &eax, &flags); + break; + case MEMSIZE: + // who cares. + eax = 64 * 1024; + ret = 0; + break; + default: + printk_info(__FUNCTION__ ": Unsupport int #0x%x\n", + intnumber); + break; + } + if (ret) + flags |= 1; // carry flags + else + flags &= ~1; + stackflags = flags; + return ret; +} + + +void +setup_realmode_idt(void) { + extern unsigned char idthandle, end_idthandle; + int i; + struct realidt *idts = (struct realidt *) 0; + int codesize = &end_idthandle - &idthandle; + unsigned char *intbyte, *codeptr; + + // for each int, we create a customized little handler + // that just pushes %ax, puts the int # in %al, + // then calls the common interrupt handler. + // this necessitated because intel didn't know much about + // architecture when they did the 8086 (it shows) + // (hmm do they know anymore even now :-) + // obviously you can see I don't really care about memory + // efficiency. If I did I would probe back through the stack + // and get it that way. But that's really disgusting. + for (i = 0; i < 256; i++) { + idts[i].cs = 0; + codeptr = (char*) 4096 + i * codesize; + idts[i].offset = (unsigned) codeptr; + memcpy(codeptr, &idthandle, codesize); + intbyte = codeptr + 3; + *intbyte = i; + } + + // fixed entry points + + // VGA BIOSes tend to hardcode f000:f065 as the previous handler of + // int10. + // calling convention here is the same as INTs, we can reuse + // the int entry code. + codeptr = (char*) 0xff065; + memcpy(codeptr, &idthandle, codesize); + intbyte = codeptr + 3; + *intbyte = 0x42; /* int42 is the relocated int10 */ +} + + + +enum { + CHECK = 0xb001, + FINDDEV = 0xb102, + READCONFBYTE = 0xb108, + READCONFWORD = 0xb109, + READCONFDWORD = 0xb10a, + WRITECONFBYTE = 0xb10b, + WRITECONFWORD = 0xb10c, + WRITECONFDWORD = 0xb10d +}; + +// errors go in AH. Just set these up so that word assigns +// will work. KISS. +enum { + PCIBIOS_NODEV = 0x8600, + PCIBIOS_BADREG = 0x8700 +}; + +int +pcibios( + unsigned long *pedi, + unsigned long *pesi, + unsigned long *pebp, + unsigned long *pesp, + unsigned long *pebx, + unsigned long *pedx, + unsigned long *pecx, + unsigned long *peax, + unsigned long *pflags + ) { + unsigned long edi = *pedi; + unsigned long esi = *pesi; + unsigned long ebp = *pebp; + unsigned long esp = *pesp; + unsigned long ebx = *pebx; + unsigned long edx = *pedx; + unsigned long ecx = *pecx; + unsigned long eax = *peax; + unsigned long flags = *pflags; + unsigned short func = (unsigned short) eax; + int retval = 0; + unsigned short devid, vendorid, devfn; + short devindex; /* Use short to get rid of gabage in upper half of 32-bit register */ + unsigned char bus; + struct pci_dev *dev; + + switch(func) { + case CHECK: + *pedx = 0x4350; + *pecx = 0x2049; + retval = 0; + break; + case FINDDEV: + { + devid = *pecx; + vendorid = *pedx; + devindex = *pesi; + dev = 0; + while ((dev = pci_find_device(vendorid, devid, dev))) { + if (devindex <= 0) + break; + devindex--; + } + if (dev) { + unsigned short busdevfn; + *peax = 0; + // busnum is an unsigned char; + // devfn is an int, so we mask it off. + busdevfn = (dev->bus->secondary << 8) + | (dev->devfn & 0xff); + printk_debug("0x%x: return 0x%x\n", func, busdevfn); + *pebx = busdevfn; + retval = 0; + } else { + *peax = PCIBIOS_NODEV; + retval = -1; + } + } + break; + case READCONFDWORD: + case READCONFWORD: + case READCONFBYTE: + case WRITECONFDWORD: + case WRITECONFWORD: + case WRITECONFBYTE: + { + unsigned long dword; + unsigned short word; + unsigned char byte; + unsigned char reg; + + devfn = *pebx & 0xff; + bus = *pebx >> 8; + reg = *pedi; + dev = pci_find_slot(bus, devfn); + if (! dev) { + printk_debug("0x%x: BAD DEVICE bus %d devfn 0x%x\n", func, bus, devfn); + // idiots. the pcibios guys assumed you'd never pass a bad bus/devfn! + *peax = PCIBIOS_BADREG; + retval = -1; + } + switch(func) { + case READCONFBYTE: + byte = pci_read_config8(dev, reg); + *pecx = byte; + break; + case READCONFWORD: + word = pci_read_config16(dev, reg); + *pecx = word; + break; + case READCONFDWORD: + dword = pci_read_config32(dev, reg); + *pecx = dword; + break; + case WRITECONFBYTE: + byte = *pecx; + write_config8(dev, reg, byte); + break; + case WRITECONFWORD: + word = *pecx; + write_config16(dev, reg, word); + break; + case WRITECONFDWORD: + word = *pecx; + write_config32(dev, reg, dword); + break; + } + + if (retval) + retval = PCIBIOS_BADREG; + printk_debug("0x%x: bus %d devfn 0x%x reg 0x%x val 0x%lx\n", func, bus, devfn, reg, *pecx); + *peax = 0; + retval = 0; + } + break; + default: + printk_err("UNSUPPORTED PCIBIOS FUNCTION 0x%x\n", func); + break; + } + + return retval; +} + +static void +vga_init(struct chip *chip, enum chip_pass pass) +{ + + struct pc80_vgabios_config *conf = + (struct pc80_vgabios_config *)chip->chip_info; + + switch (pass) { + case CONF_PASS_PRE_BOOT: + + break; + + default: + /* nothing yet */ + break; + } +} + +static void enumerate(struct chip *chip) +{ + /* don't really need to do anything */ + +} + +struct chip_control southbridge_via_vt8231_control = { + .enumerate = enumerate, + enable: vga_init, + name: "Legacy VGA bios" +}; diff --git a/src/pc80/vgachip.h b/src/pc80/vgachip.h new file mode 100644 index 0000000000..02124b3df3 --- /dev/null +++ b/src/pc80/vgachip.h @@ -0,0 +1,10 @@ +#ifndef _PC80_VGABIOS +#define _PC80_VGABIOS + +extern struct chip_control pc80_vgabios_control; + +struct pc80_vgabios_config { + int nothing; +}; + +#endif /* _PC80_VGABIOS */ |