summaryrefslogtreecommitdiff
path: root/src/pc80/vgabios.c
diff options
context:
space:
mode:
authorRonald G. Minnich <rminnich@gmail.com>2003-10-01 16:09:23 +0000
committerRonald G. Minnich <rminnich@gmail.com>2003-10-01 16:09:23 +0000
commit848d336534edb7996047fb69811d3b5d922d40ef (patch)
treed516b44a36903763ea00463f978f2924c66e467f /src/pc80/vgabios.c
parentab1f21716184faa341ab13a57b69e81d611db6c9 (diff)
vga support
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1169 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Diffstat (limited to 'src/pc80/vgabios.c')
-rw-r--r--src/pc80/vgabios.c618
1 files changed, 618 insertions, 0 deletions
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"
+};