2 * This file is part of the coreboot project.
4 * Copyright (C) 2009 coresystems GmbH
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 #include <device/pci.h>
23 #ifdef CONFIG_COREBOOT_V2
25 #include <console/console.h>
26 #define printk(x...) do_printk(x)
31 #define REALMODE_BASE ((void *)0x500)
38 uint32_t eax, ecx, edx, ebx, esp, ebp, esi, edi;
46 void x86_exception(struct eregs *info);
48 extern unsigned char __idt_handler, __idt_handler_size;
49 extern unsigned char __realmode_code, __realmode_code_size;
50 extern unsigned char __run_optionrom, __run_interrupt;
52 void (*run_optionrom)(u32 devfn) = (void *)&__run_optionrom;
53 void (*vga_enable_console)(void) = (void *)&__run_interrupt;
55 int (*intXX_handler[256])(struct eregs *regs) = { NULL };
57 static int intXX_exception_handler(struct eregs *regs)
59 printk(BIOS_INFO, "Oops, exception %d while executing option rom\n",
61 x86_exception(regs); // Call coreboot exception handler
63 return 0; // Never returns?
66 static int intXX_unknown_handler(struct eregs *regs)
68 printk(BIOS_INFO, "Unsupported software interrupt #0x%x\n",
74 int int12_handler(struct eregs *regs);
75 int int15_handler(struct eregs *regs);
76 int int1a_handler(struct eregs *regs);
78 static void setup_interrupt_handlers(void)
82 /* The first 16 intXX functions are not BIOS services,
83 * but the CPU-generated exceptions ("hardware interrupts")
85 for (i = 0; i < 0x10; i++)
86 intXX_handler[i] = &intXX_exception_handler;
88 /* Mark all other intXX calls as unknown first */
89 for (i = 0x10; i < 0x100; i++)
90 intXX_handler[i] = &intXX_unknown_handler;
92 /* Now set the default functions that are actually
93 * needed to initialize the option roms. This is very
94 * slick, as it allows us to implement mainboard specific
95 * interrupt handlers, such as the int15
97 intXX_handler[0x12] = &int12_handler;
98 intXX_handler[0x15] = &int15_handler;
99 intXX_handler[0x1a] = &int1a_handler;
102 static void write_idt_stub(void *target, u8 intnum)
104 unsigned char *codeptr;
105 codeptr = (unsigned char *) target;
106 memcpy(codeptr, &__idt_handler, (size_t)&__idt_handler_size);
107 codeptr[3] = intnum; /* modify int# in the code stub. */
110 static void setup_realmode_idt(void)
112 struct realmode_idt *idts = (struct realmode_idt *) 0;
115 /* Copy IDT stub code for each interrupt. This might seem wasteful
116 * but it is really simple
118 for (i = 0; i < 256; i++) {
120 idts[i].offset = 0x1000 + (i * (u32)&__idt_handler_size);
121 write_idt_stub((void *)((u32 )idts[i].offset), i);
124 /* Many option ROMs use the hard coded interrupt entry points in the
125 * system bios. So install them at the known locations.
126 * Only need int10 so far.
129 /* int42 is the relocated int10 */
130 write_idt_stub((void *)0xff065, 0x42);
133 void run_bios(struct device *dev, unsigned long addr)
137 /* clear vga bios data area */
138 for (i = 0x400; i < 0x500; i++) {
139 *(unsigned char *) i = 0;
142 /* Set up C interrupt handlers */
143 setup_interrupt_handlers();
145 /* Setting up realmode IDT */
146 setup_realmode_idt();
148 memcpy(REALMODE_BASE, &__realmode_code, (size_t)&__realmode_code_size);
149 printk(BIOS_SPEW, "Real mode stub @%p: %d bytes\n", REALMODE_BASE,
150 (u32)&__realmode_code_size);
152 printk(BIOS_DEBUG, "Calling Option ROM...\n");
153 run_optionrom((dev->bus->secondary << 8) | dev->path.pci.devfn);
154 printk(BIOS_DEBUG, "... Option ROM returned.\n");
157 int __attribute__((regparm(0))) interrupt_handler(u32 intnumber,
163 u32 cs_ip, u16 stackflags)
169 struct eregs reg_info;
175 printk(BIOS_DEBUG, "oprom: INT# 0x%x\n", intnumber);
176 printk(BIOS_DEBUG, "oprom: eax: %08x ebx: %08x ecx: %08x edx: %08x\n",
178 printk(BIOS_DEBUG, "oprom: ebp: %08x esp: %08x edi: %08x esi: %08x\n",
180 printk(BIOS_DEBUG, "oprom: ip: %04x cs: %04x flags: %08x\n",
183 // Fetch arguments from the stack and put them into
184 // a structure that we want to pass on to our sub interrupt
186 reg_info = (struct eregs) {
202 // Call the interrupt handler for this int#
203 ret = intXX_handler[intnumber](®_info);
205 // Put registers back on the stack. The assembler code
206 // will later pop them.
207 // What happens here is that we force (volatile!) changing
208 // the values of the parameters of this function. We do this
209 // because we know that they stay alive on the stack after
210 // we leave this function. Don't say this is bollocks.
211 *(volatile u32 *)&eax = reg_info.eax;
212 *(volatile u32 *)&ecx = reg_info.ecx;
213 *(volatile u32 *)&edx = reg_info.edx;
214 *(volatile u32 *)&ebx = reg_info.ebx;
215 *(volatile u32 *)&esi = reg_info.esi;
216 *(volatile u32 *)&edi = reg_info.edi;
217 flags = reg_info.eflags;
219 /* Pass errors back to our caller via the CARRY flag */
221 printk(BIOS_DEBUG,"error!\n");
222 flags |= 1; // error: set carry
224 flags &= ~1; // no error: clear carry
226 *(volatile u16 *)&stackflags = flags;