util/x86emu/x86.c - coreboot - Gitiles

 /*
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2009 coresystems GmbH
  *
  * 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; version 2 of the License.
  *
  * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  */

 #include <device/pci.h>
 #include <string.h>

 #include <arch/io.h>
 #include <arch/registers.h>
 #include <console/console.h>
 #include <arch/interrupt.h>

 #define REALMODE_BASE ((void *)0x600)

 struct realmode_idt {
 	u16 offset, cs;
 };

 void x86_exception(struct eregs *info);

 extern unsigned char __idt_handler, __idt_handler_size;
 extern unsigned char __realmode_code, __realmode_code_size;
 extern unsigned char __run_optionrom, __run_interrupt;

 void (*run_optionrom)(u32 devfn) __attribute__((regparm(0))) = (void *)&__run_optionrom;
 void (*vga_enable_console)(void) __attribute__((regparm(0))) = (void *)&__run_interrupt;

 int (*intXX_handler[256])(struct eregs *regs) = { NULL };

 static int intXX_exception_handler(struct eregs *regs)
 {
 	printk(BIOS_INFO, "Oops, exception %d while executing option rom\n",
 			regs->vector);
 	x86_exception(regs);	// Call coreboot exception handler

 	return 0;		// Never returns?
 }

 static int intXX_unknown_handler(struct eregs *regs)
 {
 	printk(BIOS_INFO, "Unsupported software interrupt #0x%x\n",
 			regs->vector);

 	return -1;
 }

 /* setup interrupt handlers for mainboard */
 void mainboard_interrupt_handlers(int intXX, void *intXX_func)
 {
 	intXX_handler[intXX] = intXX_func;
 }

 int int12_handler(struct eregs *regs);
 int int15_handler(struct eregs *regs);
 int int1a_handler(struct eregs *regs);

 static void setup_interrupt_handlers(void)
 {
 	int i;

 	/* The first 16 intXX functions are not BIOS services,
 	 * but the CPU-generated exceptions ("hardware interrupts")
 	 */
 	for (i = 0; i < 0x10; i++)
 		intXX_handler[i] = &intXX_exception_handler;

 	/* Mark all other intXX calls as unknown first */
 	for (i = 0x10; i < 0x100; i++)
 	{
 		/* If the mainboard_interrupt_handler isn't called first.
 		 */
 		if(!intXX_handler[i])
 		{
 			/* Now set the default functions that are actually
 			 * needed to initialize the option roms. This is very
 			 * slick, as it allows us to implement mainboard specific
 			 * interrupt handlers, such as the int15
 			 */
 			switch (i) {
 			case 0x12:
 				intXX_handler[0x12] = &int12_handler;
 				break;
 			case 0x15:
 				intXX_handler[0x15] = &int15_handler;
 				break;
 			case 0x1a:
 				intXX_handler[0x1a] = &int1a_handler;
 				break;
 			default:
 				intXX_handler[i] = &intXX_unknown_handler;
 				break;
 			}
 		}
 	}
 }

 static void write_idt_stub(void *target, u8 intnum)
 {
 	unsigned char *codeptr;
 	codeptr = (unsigned char *) target;
 	memcpy(codeptr, &__idt_handler, (size_t)&__idt_handler_size);
 	codeptr[3] = intnum; /* modify int# in the code stub. */
 }

 static void setup_realmode_idt(void)
 {
 	struct realmode_idt *idts = (struct realmode_idt *) 0;
 	int i;

 	/* Copy IDT stub code for each interrupt. This might seem wasteful
 	 * but it is really simple
 	 */
 	 for (i = 0; i < 256; i++) {
 		idts[i].cs = 0;
 		idts[i].offset = 0x1000 + (i * (u32)&__idt_handler_size);
 		write_idt_stub((void *)((u32 )idts[i].offset), i);
 	}

 	/* Many option ROMs use the hard coded interrupt entry points in the
 	 * system bios. So install them at the known locations.
 	 * Only need int10 so far.
 	 */

 	/* int42 is the relocated int10 */
 	write_idt_stub((void *)0xff065, 0x42);
 }

 void run_bios(struct device *dev, unsigned long addr)
 {
 	/* clear vga bios data area */
 	memset((void *)0x400, 0, 0x200);

 	/* Set up C interrupt handlers */
 	setup_interrupt_handlers();

 	/* Setting up realmode IDT */
 	setup_realmode_idt();

 	memcpy(REALMODE_BASE, &__realmode_code, (size_t)&__realmode_code_size);
 	printk(BIOS_SPEW, "Real mode stub @%p: %d bytes\n", REALMODE_BASE,
 			(u32)&__realmode_code_size);

 	printk(BIOS_DEBUG, "Calling Option ROM...\n");
 	run_optionrom((dev->bus->secondary << 8) | dev->path.pci.devfn);
 	printk(BIOS_DEBUG, "... Option ROM returned.\n");
 }

 int __attribute__((regparm(0))) interrupt_handler(u32 intnumber,
 	    u32 gsfs, u32 dses,
 	    u32 edi, u32 esi,
 	    u32 ebp, u32 esp,
 	    u32 ebx, u32 edx,
 	    u32 ecx, u32 eax,
 	    u32 cs_ip, u16 stackflags);

 int __attribute__((regparm(0))) interrupt_handler(u32 intnumber,
 	    u32 gsfs, u32 dses,
 	    u32 edi, u32 esi,
 	    u32 ebp, u32 esp,
 	    u32 ebx, u32 edx,
 	    u32 ecx, u32 eax,
 	    u32 cs_ip, u16 stackflags)
 {
 	u32 ip;
 	u32 cs;
 	u32 flags;
 	int ret = -1;
 	struct eregs reg_info;

 	ip = cs_ip & 0xffff;
 	cs = cs_ip >> 16;
 	flags = stackflags;

 	printk(BIOS_DEBUG, "oprom: INT# 0x%x\n", intnumber);
 	printk(BIOS_DEBUG, "oprom: eax: %08x ebx: %08x ecx: %08x edx: %08x\n",
 		      eax, ebx, ecx, edx);
 	printk(BIOS_DEBUG, "oprom: ebp: %08x esp: %08x edi: %08x esi: %08x\n",
 		     ebp, esp, edi, esi);
 	printk(BIOS_DEBUG, "oprom:  ip: %04x      cs: %04x   flags: %08x\n",
 		     ip, cs, flags);

 	// Fetch arguments from the stack and put them into
 	// a structure that we want to pass on to our sub interrupt
 	// handlers.
 	reg_info = (struct eregs) {
 		.eax=eax,
 		.ecx=ecx,
 		.edx=edx,
 		.ebx=ebx,
 		.esp=esp,
 		.ebp=ebp,
 		.esi=esi,
 		.edi=edi,
 		.vector=intnumber,
 		.error_code=0, // ??
 		.eip=ip,
 		.cs=cs,
 		.eflags=flags // ??
 	};

 	// Call the interrupt handler for this int#
 	ret = intXX_handler[intnumber](&reg_info);

 	// Put registers back on the stack. The assembler code
 	// will later pop them.
 	// What happens here is that we force (volatile!) changing
 	// the values of the parameters of this function. We do this
 	// because we know that they stay alive on the stack after
 	// we leave this function. Don't say this is bollocks.
 	*(volatile u32 *)&eax = reg_info.eax;
 	*(volatile u32 *)&ecx = reg_info.ecx;
 	*(volatile u32 *)&edx = reg_info.edx;
 	*(volatile u32 *)&ebx = reg_info.ebx;
 	*(volatile u32 *)&esi = reg_info.esi;
 	*(volatile u32 *)&edi = reg_info.edi;
 	flags = reg_info.eflags;

 	/* Pass errors back to our caller via the CARRY flag */
 	if (ret) {
 		printk(BIOS_DEBUG,"error!\n");
 		flags |= 1;  // error: set carry
 	}else{
 		flags &= ~1; // no error: clear carry
 	}
 	*(volatile u16 *)&stackflags = flags;

 	return ret;
 }
	/*
	* This file is part of the coreboot project.
	*
	* Copyright (C) 2009 coresystems GmbH
	*
	* 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; version 2 of the License.
	*
	* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
	*/

	#include <device/pci.h>
	#include <string.h>

	#include <arch/io.h>
	#include <arch/registers.h>
	#include <console/console.h>
	#include <arch/interrupt.h>

	#define REALMODE_BASE ((void *)0x600)

	struct realmode_idt {
	u16 offset, cs;
	};

	void x86_exception(struct eregs *info);

	extern unsigned char __idt_handler, __idt_handler_size;
	extern unsigned char __realmode_code, __realmode_code_size;
	extern unsigned char __run_optionrom, __run_interrupt;

	void (run_optionrom)(u32 devfn) __attribute__((regparm(0))) = (void )&__run_optionrom;
	void (vga_enable_console)(void) __attribute__((regparm(0))) = (void )&__run_interrupt;

	int (intXX_handler[256])(struct eregs regs) = { NULL };

	static int intXX_exception_handler(struct eregs *regs)
	{
	printk(BIOS_INFO, "Oops, exception %d while executing option rom\n",
	regs->vector);
	x86_exception(regs); // Call coreboot exception handler

	return 0; // Never returns?
	}

	static int intXX_unknown_handler(struct eregs *regs)
	{
	printk(BIOS_INFO, "Unsupported software interrupt #0x%x\n",
	regs->vector);

	return -1;
	}

	/* setup interrupt handlers for mainboard */
	void mainboard_interrupt_handlers(int intXX, void *intXX_func)
	{
	intXX_handler[intXX] = intXX_func;
	}

	int int12_handler(struct eregs *regs);
	int int15_handler(struct eregs *regs);
	int int1a_handler(struct eregs *regs);

	static void setup_interrupt_handlers(void)
	{
	int i;

	/* The first 16 intXX functions are not BIOS services,
	* but the CPU-generated exceptions ("hardware interrupts")
	*/
	for (i = 0; i < 0x10; i++)
	intXX_handler[i] = &intXX_exception_handler;

	/* Mark all other intXX calls as unknown first */
	for (i = 0x10; i < 0x100; i++)
	{
	/* If the mainboard_interrupt_handler isn't called first.
	*/
	if(!intXX_handler[i])
	{
	/* Now set the default functions that are actually
	* needed to initialize the option roms. This is very
	* slick, as it allows us to implement mainboard specific
	* interrupt handlers, such as the int15
	*/
	switch (i) {
	case 0x12:
	intXX_handler[0x12] = &int12_handler;
	break;
	case 0x15:
	intXX_handler[0x15] = &int15_handler;
	break;
	case 0x1a:
	intXX_handler[0x1a] = &int1a_handler;
	break;
	default:
	intXX_handler[i] = &intXX_unknown_handler;
	break;
	}
	}
	}
	}

	static void write_idt_stub(void *target, u8 intnum)
	{
	unsigned char *codeptr;
	codeptr = (unsigned char *) target;
	memcpy(codeptr, &__idt_handler, (size_t)&__idt_handler_size);
	codeptr[3] = intnum; /* modify int# in the code stub. */
	}

	static void setup_realmode_idt(void)
	{
	struct realmode_idt idts = (struct realmode_idt ) 0;
	int i;

	/* Copy IDT stub code for each interrupt. This might seem wasteful
	* but it is really simple
	*/
	for (i = 0; i < 256; i++) {
	idts[i].cs = 0;
	idts[i].offset = 0x1000 + (i * (u32)&__idt_handler_size);
	write_idt_stub((void *)((u32 )idts[i].offset), i);
	}

	/* Many option ROMs use the hard coded interrupt entry points in the
	* system bios. So install them at the known locations.
	* Only need int10 so far.
	*/

	/* int42 is the relocated int10 */
	write_idt_stub((void *)0xff065, 0x42);
	}

	void run_bios(struct device *dev, unsigned long addr)
	{
	/* clear vga bios data area */
	memset((void *)0x400, 0, 0x200);

	/* Set up C interrupt handlers */
	setup_interrupt_handlers();

	/* Setting up realmode IDT */
	setup_realmode_idt();

	memcpy(REALMODE_BASE, &__realmode_code, (size_t)&__realmode_code_size);
	printk(BIOS_SPEW, "Real mode stub @%p: %d bytes\n", REALMODE_BASE,
	(u32)&__realmode_code_size);

	printk(BIOS_DEBUG, "Calling Option ROM...\n");
	run_optionrom((dev->bus->secondary << 8) \| dev->path.pci.devfn);
	printk(BIOS_DEBUG, "... Option ROM returned.\n");
	}

	int __attribute__((regparm(0))) interrupt_handler(u32 intnumber,
	u32 gsfs, u32 dses,
	u32 edi, u32 esi,
	u32 ebp, u32 esp,
	u32 ebx, u32 edx,
	u32 ecx, u32 eax,
	u32 cs_ip, u16 stackflags);

	int __attribute__((regparm(0))) interrupt_handler(u32 intnumber,
	u32 gsfs, u32 dses,
	u32 edi, u32 esi,
	u32 ebp, u32 esp,
	u32 ebx, u32 edx,
	u32 ecx, u32 eax,
	u32 cs_ip, u16 stackflags)
	{
	u32 ip;
	u32 cs;
	u32 flags;
	int ret = -1;
	struct eregs reg_info;

	ip = cs_ip & 0xffff;
	cs = cs_ip >> 16;
	flags = stackflags;

	printk(BIOS_DEBUG, "oprom: INT# 0x%x\n", intnumber);
	printk(BIOS_DEBUG, "oprom: eax: %08x ebx: %08x ecx: %08x edx: %08x\n",
	eax, ebx, ecx, edx);
	printk(BIOS_DEBUG, "oprom: ebp: %08x esp: %08x edi: %08x esi: %08x\n",
	ebp, esp, edi, esi);
	printk(BIOS_DEBUG, "oprom: ip: %04x cs: %04x flags: %08x\n",
	ip, cs, flags);

	// Fetch arguments from the stack and put them into
	// a structure that we want to pass on to our sub interrupt
	// handlers.
	reg_info = (struct eregs) {
	.eax=eax,
	.ecx=ecx,
	.edx=edx,
	.ebx=ebx,
	.esp=esp,
	.ebp=ebp,
	.esi=esi,
	.edi=edi,
	.vector=intnumber,
	.error_code=0, // ??
	.eip=ip,
	.cs=cs,
	.eflags=flags // ??
	};

	// Call the interrupt handler for this int#
	ret = intXX_handler[intnumber](&reg_info);

	// Put registers back on the stack. The assembler code
	// will later pop them.
	// What happens here is that we force (volatile!) changing
	// the values of the parameters of this function. We do this
	// because we know that they stay alive on the stack after
	// we leave this function. Don't say this is bollocks.
	(volatile u32 )&eax = reg_info.eax;
	(volatile u32 )&ecx = reg_info.ecx;
	(volatile u32 )&edx = reg_info.edx;
	(volatile u32 )&ebx = reg_info.ebx;
	(volatile u32 )&esi = reg_info.esi;
	(volatile u32 )&edi = reg_info.edi;
	flags = reg_info.eflags;

	/* Pass errors back to our caller via the CARRY flag */
	if (ret) {
	printk(BIOS_DEBUG,"error!\n");
	flags \|= 1; // error: set carry
	}else{
	flags &= ~1; // no error: clear carry
	}
	(volatile u16 )&stackflags = flags;

	return ret;
	}