vga support

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1169 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

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 */