diff options
Diffstat (limited to 'cpu/i386/interrupts.c')
-rw-r--r-- | cpu/i386/interrupts.c | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/cpu/i386/interrupts.c b/cpu/i386/interrupts.c new file mode 100644 index 0000000..81d6881 --- /dev/null +++ b/cpu/i386/interrupts.c @@ -0,0 +1,583 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB, daniel@omicron.se. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 + */ + +#include <common.h> +#include <syscall.h> +#include <malloc.h> +#include <asm/io.h> +#include <asm/i8259.h> +#include <asm/ibmpc.h> + + +#if 0 +/* done */ +int interrupt_init (void); +void irq_install_handler(int, interrupt_handler_t *, void *); +void irq_free_handler (int); +void enable_interrupts (void); +int disable_interrupts (void); + +/* todo */ +void timer_interrupt (struct pt_regs *); +void external_interrupt (struct pt_regs *); +void reset_timer (void); +ulong get_timer (ulong base); +void set_timer (ulong t); + +#endif + +struct idt_entry { + u16 base_low; + u16 selector; + u8 res; + u8 access; + u16 base_high; +} __attribute__ ((packed)); + + +struct idt_entry idt[256]; + + +#define MAX_IRQ 16 + +typedef struct irq_handler { + struct irq_handler *next; + interrupt_handler_t* isr_func; + void *isr_data; +} irq_handler_t; + +#define IRQ_DISABLED 1 + +typedef struct { + irq_handler_t *handler; + unsigned long status; +} irq_desc_t; + +static irq_desc_t irq_table[MAX_IRQ]; + + +/* syscall stuff, very untested + * the current approach which includes copying + * part of the stack will work badly for + * varargs functions. + * if we were to store the top three words on the + * stack (eip, ss, eflags) somwhere and add 14 to + * %esp .... + */ +asm(".globl syscall_entry\n" \ + "syscall_entry:\n" \ + "movl 12(%esp), %eax\n" \ + "movl %esp, %ebx\n" \ + "addl $16, %ebx\n" \ + "pushl %ebx\n" \ + "pushl %eax\n" \ + "call do_syscall\n" \ + "addl $8, %esp\n" \ + "iret\n"); + +void __attribute__ ((regparm(0))) syscall_entry(void); + +int __attribute__ ((regparm(0))) do_syscall(u32 nr, u32 *stack) +{ + if (nr<NR_SYSCALLS) { + /* We copy 8 args of the syscall, + * this will be a problem with the + * printf syscall .... */ + int (*fp)(u32, u32, u32, u32, + u32, u32, u32, u32); + fp = syscall_tbl[nr]; + return fp(stack[0], stack[1], stack[2], stack[3], + stack[4], stack[5], stack[6], stack[7]); + } + + return -1; +} + + +asm ("irq_return:\n" + " addl $4, %esp\n" + " popa\n" + " iret\n"); + +asm ("exp_return:\n" + " addl $12, %esp\n" + " pop %esp\n" + " popa\n" + " iret\n"); + +char exception_stack[4096]; + +#define DECLARE_INTERRUPT(x) \ + asm(".globl irq_"#x"\n" \ + "irq_"#x":\n" \ + "pusha \n" \ + "pushl $"#x"\n" \ + "pushl $irq_return\n" \ + "jmp do_irq\n"); \ + void __attribute__ ((regparm(0))) irq_##x(void) + +#define DECLARE_EXCEPTION(x, f) \ + asm(".globl exp_"#x"\n" \ + "exp_"#x":\n" \ + "pusha \n" \ + "movl %esp, %ebx\n" \ + "movl $exception_stack, %eax\n" \ + "movl %eax, %esp \n" \ + "pushl %ebx\n" \ + "movl 32(%esp), %ebx\n" \ + "xorl %edx, %edx\n" \ + "movw 36(%esp), %dx\n" \ + "pushl %edx\n" \ + "pushl %ebx\n" \ + "pushl $"#x"\n" \ + "pushl $exp_return\n" \ + "jmp "#f"\n"); \ + void __attribute__ ((regparm(0))) exp_##x(void) + +DECLARE_EXCEPTION(0, divide_exception_entry); /* Divide exception */ +DECLARE_EXCEPTION(1, debug_exception_entry); /* Debug exception */ +DECLARE_EXCEPTION(2, nmi_entry); /* NMI */ +DECLARE_EXCEPTION(3, unknown_exception_entry); /* Breakpoint/Coprocessor Error */ +DECLARE_EXCEPTION(4, unknown_exception_entry); /* Overflow */ +DECLARE_EXCEPTION(5, unknown_exception_entry); /* Bounds */ +DECLARE_EXCEPTION(6, invalid_instruction_entry); /* Invalid instruction */ +DECLARE_EXCEPTION(7, unknown_exception_entry); /* Device not present */ +DECLARE_EXCEPTION(8, double_fault_entry); /* Double fault */ +DECLARE_EXCEPTION(9, unknown_exception_entry); /* Co-processor segment overrun */ +DECLARE_EXCEPTION(10, invalid_tss_exception_entry);/* Invalid TSS */ +DECLARE_EXCEPTION(11, seg_fault_entry); /* Segment not present */ +DECLARE_EXCEPTION(12, stack_fault_entry); /* Stack overflow */ +DECLARE_EXCEPTION(13, gpf_entry); /* GPF */ +DECLARE_EXCEPTION(14, page_fault_entry); /* PF */ +DECLARE_EXCEPTION(15, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(16, fp_exception_entry); /* Floating point */ +DECLARE_EXCEPTION(17, alignment_check_entry); /* alignment check */ +DECLARE_EXCEPTION(18, machine_check_entry); /* machine check */ +DECLARE_EXCEPTION(19, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(20, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(21, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(22, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(23, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(24, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(25, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(26, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(27, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(28, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(29, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(30, unknown_exception_entry); /* Reserved */ +DECLARE_EXCEPTION(31, unknown_exception_entry); /* Reserved */ + +DECLARE_INTERRUPT(0); +DECLARE_INTERRUPT(1); +DECLARE_INTERRUPT(3); +DECLARE_INTERRUPT(4); +DECLARE_INTERRUPT(5); +DECLARE_INTERRUPT(6); +DECLARE_INTERRUPT(7); +DECLARE_INTERRUPT(8); +DECLARE_INTERRUPT(9); +DECLARE_INTERRUPT(10); +DECLARE_INTERRUPT(11); +DECLARE_INTERRUPT(12); +DECLARE_INTERRUPT(13); +DECLARE_INTERRUPT(14); +DECLARE_INTERRUPT(15); + +void __attribute__ ((regparm(0))) default_isr(void); +asm ("default_isr: iret\n"); + +void disable_irq(int irq) +{ + if (irq >= MAX_IRQ) { + return; + } + irq_table[irq].status |= IRQ_DISABLED; + +} + +void enable_irq(int irq) +{ + if (irq >= MAX_IRQ) { + return; + } + irq_table[irq].status &= ~IRQ_DISABLED; +} + +/* masks one specific IRQ in the PIC */ +static void unmask_irq(int irq) +{ + int imr_port; + + if (irq >= MAX_IRQ) { + return; + } + if (irq > 7) { + imr_port = SLAVE_PIC + IMR; + } else { + imr_port = MASTER_PIC + IMR; + } + + outb(inb(imr_port)&~(1<<(irq&7)), imr_port); +} + + +/* unmasks one specific IRQ in the PIC */ +static void mask_irq(int irq) +{ + int imr_port; + + if (irq >= MAX_IRQ) { + return; + } + if (irq > 7) { + imr_port = SLAVE_PIC + IMR; + } else { + imr_port = MASTER_PIC + IMR; + } + + outb(inb(imr_port)|(1<<(irq&7)), imr_port); +} + + +/* issue a Specific End Of Interrupt instruciton */ +static void specific_eoi(int irq) +{ + /* If it is on the slave PIC this have to be performed on + * both the master and the slave PICs */ + if (irq > 7) { + outb(OCW2_SEOI|(irq&7), SLAVE_PIC + OCW2); + irq = SEOI_IR2; /* also do IR2 on master */ + } + outb(OCW2_SEOI|irq, MASTER_PIC + OCW2); +} + +void __attribute__ ((regparm(0))) do_irq(int irq) +{ + + mask_irq(irq); + + if (irq_table[irq].status & IRQ_DISABLED) { + unmask_irq(irq); + specific_eoi(irq); + return; + } + + + if (NULL != irq_table[irq].handler) { + irq_handler_t *handler; + for (handler = irq_table[irq].handler; + NULL!= handler; handler = handler->next) { + handler->isr_func(handler->isr_data); + } + } else { + if ((irq & 7) != 7) { + printf("Spurious irq %d\n", irq); + } + } + unmask_irq(irq); + specific_eoi(irq); +} + + +void __attribute__ ((regparm(0))) unknown_exception_entry(int cause, int ip, int seg) +{ + printf("Unknown Exception %d at %04x:%08x\n", cause, seg, ip); +} + +void __attribute__ ((regparm(0))) divide_exception_entry(int cause, int ip, int seg) +{ + printf("Divide Error (Division by zero) at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) debug_exception_entry(int cause, int ip, int seg) +{ + printf("Debug Interrupt (Single step) at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) nmi_entry(int cause, int ip, int seg) +{ + printf("NMI Interrupt at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) invalid_instruction_entry(int cause, int ip, int seg) +{ + printf("Invalid Instruction at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) double_fault_entry(int cause, int ip, int seg) +{ + printf("Double fault at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) invalid_tss_exception_entry(int cause, int ip, int seg) +{ + printf("Invalid TSS at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) seg_fault_entry(int cause, int ip, int seg) +{ + printf("Segmentation fault at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) stack_fault_entry(int cause, int ip, int seg) +{ + printf("Stack fault at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) gpf_entry(int cause, int ip, int seg) +{ + printf("General protection fault at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) page_fault_entry(int cause, int ip, int seg) +{ + printf("Page fault at %04x:%08x\n", seg, ip); + while(1); +} + +void __attribute__ ((regparm(0))) fp_exception_entry(int cause, int ip, int seg) +{ + printf("Floating point exception at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) alignment_check_entry(int cause, int ip, int seg) +{ + printf("Alignment check at %04x:%08x\n", seg, ip); +} + +void __attribute__ ((regparm(0))) machine_check_entry(int cause, int ip, int seg) +{ + printf("Machine check exception at %04x:%08x\n", seg, ip); +} + + +void irq_install_handler(int ino, interrupt_handler_t *func, void *pdata) +{ + int status; + + if (ino>MAX_IRQ) { + return; + } + + if (NULL != irq_table[ino].handler) { + return; + } + + status = disable_interrupts(); + irq_table[ino].handler = malloc(sizeof(irq_handler_t)); + if (NULL == irq_table[ino].handler) { + return; + } + + memset(irq_table[ino].handler, 0, sizeof(irq_handler_t)); + + irq_table[ino].handler->isr_func = func; + irq_table[ino].handler->isr_data = pdata; + if (status) { + enable_interrupts(); + } + + unmask_irq(ino); + + return; +} + +void irq_free_handler(int ino) +{ + int status; + if (ino>MAX_IRQ) { + return; + } + + status = disable_interrupts(); + mask_irq(ino); + if (NULL == irq_table[ino].handler) { + return; + } + free(irq_table[ino].handler); + irq_table[ino].handler=NULL; + if (status) { + enable_interrupts(); + } + return; +} + + +asm ("idt_ptr:\n" + ".word 0x800\n" /* size of the table 8*256 bytes */ + ".long idt\n" /* offset */ + ".word 0x18\n");/* data segment */ + +static void set_vector(int intnum, void *routine) +{ + idt[intnum].base_high = (u16)((u32)(routine)>>16); + idt[intnum].base_low = (u16)((u32)(routine)&0xffff); +} + + +int interrupt_init(void) +{ + int i; + + /* Just in case... */ + disable_interrupts(); + + /* Initialize the IDT and stuff */ + + + memset(irq_table, 0, sizeof(irq_table)); + + /* Setup the IDT */ + for (i=0;i<256;i++) { + idt[i].access = 0x8e; + idt[i].res = 0; + idt[i].selector = 0x10; + set_vector(i, default_isr); + } + + asm ("cs lidt idt_ptr\n"); + + /* Setup exceptions */ + set_vector(0x00, exp_0); + set_vector(0x01, exp_1); + set_vector(0x02, exp_2); + set_vector(0x03, exp_3); + set_vector(0x04, exp_4); + set_vector(0x05, exp_5); + set_vector(0x06, exp_6); + set_vector(0x07, exp_7); + set_vector(0x08, exp_8); + set_vector(0x09, exp_9); + set_vector(0x0a, exp_10); + set_vector(0x0b, exp_11); + set_vector(0x0c, exp_12); + set_vector(0x0d, exp_13); + set_vector(0x0e, exp_14); + set_vector(0x0f, exp_15); + set_vector(0x10, exp_16); + set_vector(0x11, exp_17); + set_vector(0x12, exp_18); + set_vector(0x13, exp_19); + set_vector(0x14, exp_20); + set_vector(0x15, exp_21); + set_vector(0x16, exp_22); + set_vector(0x17, exp_23); + set_vector(0x18, exp_24); + set_vector(0x19, exp_25); + set_vector(0x1a, exp_26); + set_vector(0x1b, exp_27); + set_vector(0x1c, exp_28); + set_vector(0x1d, exp_29); + set_vector(0x1e, exp_30); + set_vector(0x1f, exp_31); + + + /* Setup interrupts */ + set_vector(0x20, irq_0); + set_vector(0x21, irq_1); + set_vector(0x23, irq_3); + set_vector(0x24, irq_4); + set_vector(0x25, irq_5); + set_vector(0x26, irq_6); + set_vector(0x27, irq_7); + set_vector(0x28, irq_8); + set_vector(0x29, irq_9); + set_vector(0x2a, irq_10); + set_vector(0x2b, irq_11); + set_vector(0x2c, irq_12); + set_vector(0x2d, irq_13); + set_vector(0x2e, irq_14); + set_vector(0x2f, irq_15); + /* vectors 0x30-0x3f are reserved for irq 16-31 */ + set_vector(0x40, syscall_entry); + + + /* Mask all interrupts */ + outb(0xff, MASTER_PIC + IMR); + outb(0xff, SLAVE_PIC + IMR); + + /* Master PIC */ + outb(ICW1_SEL|ICW1_EICW4, MASTER_PIC + ICW1); + outb(0x20, MASTER_PIC + ICW2); /* Place master PIC interrupts at INT20 */ + outb(IR2, MASTER_PIC + ICW3); /* ICW3, One slevc PIC is present */ + outb(ICW4_PM, MASTER_PIC + ICW4); + + for (i=0;i<8;i++) { + outb(OCW2_SEOI|i, MASTER_PIC + OCW2); + } + + /* Slave PIC */ + outb(ICW1_SEL|ICW1_EICW4, SLAVE_PIC + ICW1); + outb(0x28, SLAVE_PIC + ICW2); /* Place slave PIC interrupts at INT28 */ + outb(0x02, SLAVE_PIC + ICW3); /* Slave ID */ + outb(ICW4_PM, SLAVE_PIC + ICW4); + + for (i=0;i<8;i++) { + outb(OCW2_SEOI|i, SLAVE_PIC + OCW2); + } + + + /* enable cascade interrerupt */ + outb(0xfb, MASTER_PIC + IMR); + outb(0xff, SLAVE_PIC + IMR); + + /* It is now safe to enable interrupts */ + enable_interrupts(); + + return 0; +} + +void enable_interrupts(void) +{ + asm("sti\n"); +} + +int disable_interrupts(void) +{ + long flags; + + asm volatile ("pushfl ; popl %0 ; cli\n" : "=g" (flags) : ); + + return (flags&0x200); /* IE flags is bit 9 */ +} + + +#ifdef CFG_RESET_GENERIC + +void __attribute__ ((regparm(0))) generate_gpf(void); +asm(".globl generate_gpf\n" + "generate_gpf:\n" + "ljmp $0x70, $0x47114711\n"); /* segment 0x70 is an arbitrary segment which does not + * exist */ +void reset_cpu(ulong addr) +{ + set_vector(13, generate_gpf); /* general protection fault handler */ + set_vector(8, generate_gpf); /* double fault handler */ + generate_gpf(); /* start the show */ +} +#endif |