| /* |
| * 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); |
| void run_bios(struct device *dev, unsigned long addr); |
| |
| 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](®_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; |
| } |
| |