3 * Daniel Engström, Omicron Ceti AB, daniel@omicron.se.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
28 #include <asm/i8259.h>
29 #include <asm/ibmpc.h>
39 } __attribute__ ((packed));
42 struct idt_entry idt[256];
47 typedef struct irq_handler {
48 struct irq_handler *next;
49 interrupt_handler_t* isr_func;
53 #define IRQ_DISABLED 1
56 irq_handler_t *handler;
60 static irq_desc_t irq_table[MAX_IRQ];
64 asm(".globl syscall_entry\n" \
66 "popl %ebx\n" /* throw away the return address, flags */ \
67 "popl %ebx\n" /* and segment that the INT instruction pushed */ \
68 "popl %ebx\n" /* on to the stack */ \
69 "movl %eax, %ecx\n" /* load the syscall nr argument*/ \
70 "movl syscall_tbl, %eax\n" /* load start of syscall table */ \
71 "cmpl $(11-1), %ecx\n" /* FixMe: find a way to use NR_SYSCALLS macro here */ \
73 "movl (%eax, %ecx, 4), %eax\n" /* load the handler of the syscall*/ \
74 "test %eax, %eax\n" /* test for null */ \
80 "bad_syscall: movl $0xffffffff, %eax\n" \
85 void __attribute__ ((regparm(0))) syscall_entry(void);
99 char exception_stack[4096];
101 #define DECLARE_INTERRUPT(x) \
102 asm(".globl irq_"#x"\n" \
106 "pushl $irq_return\n" \
108 void __attribute__ ((regparm(0))) irq_##x(void)
110 #define DECLARE_EXCEPTION(x, f) \
111 asm(".globl exp_"#x"\n" \
114 "movl %esp, %ebx\n" \
115 "movl $exception_stack, %eax\n" \
116 "movl %eax, %esp \n" \
118 "movl 32(%esp), %ebx\n" \
119 "xorl %edx, %edx\n" \
120 "movw 36(%esp), %dx\n" \
124 "pushl $exp_return\n" \
126 void __attribute__ ((regparm(0))) exp_##x(void)
128 DECLARE_EXCEPTION(0, divide_exception_entry); /* Divide exception */
129 DECLARE_EXCEPTION(1, debug_exception_entry); /* Debug exception */
130 DECLARE_EXCEPTION(2, nmi_entry); /* NMI */
131 DECLARE_EXCEPTION(3, unknown_exception_entry); /* Breakpoint/Coprocessor Error */
132 DECLARE_EXCEPTION(4, unknown_exception_entry); /* Overflow */
133 DECLARE_EXCEPTION(5, unknown_exception_entry); /* Bounds */
134 DECLARE_EXCEPTION(6, invalid_instruction_entry); /* Invalid instruction */
135 DECLARE_EXCEPTION(7, unknown_exception_entry); /* Device not present */
136 DECLARE_EXCEPTION(8, double_fault_entry); /* Double fault */
137 DECLARE_EXCEPTION(9, unknown_exception_entry); /* Co-processor segment overrun */
138 DECLARE_EXCEPTION(10, invalid_tss_exception_entry);/* Invalid TSS */
139 DECLARE_EXCEPTION(11, seg_fault_entry); /* Segment not present */
140 DECLARE_EXCEPTION(12, stack_fault_entry); /* Stack overflow */
141 DECLARE_EXCEPTION(13, gpf_entry); /* GPF */
142 DECLARE_EXCEPTION(14, page_fault_entry); /* PF */
143 DECLARE_EXCEPTION(15, unknown_exception_entry); /* Reserved */
144 DECLARE_EXCEPTION(16, fp_exception_entry); /* Floating point */
145 DECLARE_EXCEPTION(17, alignment_check_entry); /* alignment check */
146 DECLARE_EXCEPTION(18, machine_check_entry); /* machine check */
147 DECLARE_EXCEPTION(19, unknown_exception_entry); /* Reserved */
148 DECLARE_EXCEPTION(20, unknown_exception_entry); /* Reserved */
149 DECLARE_EXCEPTION(21, unknown_exception_entry); /* Reserved */
150 DECLARE_EXCEPTION(22, unknown_exception_entry); /* Reserved */
151 DECLARE_EXCEPTION(23, unknown_exception_entry); /* Reserved */
152 DECLARE_EXCEPTION(24, unknown_exception_entry); /* Reserved */
153 DECLARE_EXCEPTION(25, unknown_exception_entry); /* Reserved */
154 DECLARE_EXCEPTION(26, unknown_exception_entry); /* Reserved */
155 DECLARE_EXCEPTION(27, unknown_exception_entry); /* Reserved */
156 DECLARE_EXCEPTION(28, unknown_exception_entry); /* Reserved */
157 DECLARE_EXCEPTION(29, unknown_exception_entry); /* Reserved */
158 DECLARE_EXCEPTION(30, unknown_exception_entry); /* Reserved */
159 DECLARE_EXCEPTION(31, unknown_exception_entry); /* Reserved */
161 DECLARE_INTERRUPT(0);
162 DECLARE_INTERRUPT(1);
163 DECLARE_INTERRUPT(3);
164 DECLARE_INTERRUPT(4);
165 DECLARE_INTERRUPT(5);
166 DECLARE_INTERRUPT(6);
167 DECLARE_INTERRUPT(7);
168 DECLARE_INTERRUPT(8);
169 DECLARE_INTERRUPT(9);
170 DECLARE_INTERRUPT(10);
171 DECLARE_INTERRUPT(11);
172 DECLARE_INTERRUPT(12);
173 DECLARE_INTERRUPT(13);
174 DECLARE_INTERRUPT(14);
175 DECLARE_INTERRUPT(15);
177 void __attribute__ ((regparm(0))) default_isr(void);
178 asm ("default_isr: iret\n");
180 void disable_irq(int irq)
182 if (irq >= MAX_IRQ) {
185 irq_table[irq].status |= IRQ_DISABLED;
189 void enable_irq(int irq)
191 if (irq >= MAX_IRQ) {
194 irq_table[irq].status &= ~IRQ_DISABLED;
197 /* masks one specific IRQ in the PIC */
198 static void unmask_irq(int irq)
202 if (irq >= MAX_IRQ) {
206 imr_port = SLAVE_PIC + IMR;
208 imr_port = MASTER_PIC + IMR;
211 outb(inb(imr_port)&~(1<<(irq&7)), imr_port);
215 /* unmasks one specific IRQ in the PIC */
216 static void mask_irq(int irq)
220 if (irq >= MAX_IRQ) {
224 imr_port = SLAVE_PIC + IMR;
226 imr_port = MASTER_PIC + IMR;
229 outb(inb(imr_port)|(1<<(irq&7)), imr_port);
233 /* issue a Specific End Of Interrupt instruciton */
234 static void specific_eoi(int irq)
236 /* If it is on the slave PIC this have to be performed on
237 * both the master and the slave PICs */
239 outb(OCW2_SEOI|(irq&7), SLAVE_PIC + OCW2);
240 irq = SEOI_IR2; /* also do IR2 on master */
242 outb(OCW2_SEOI|irq, MASTER_PIC + OCW2);
245 void __attribute__ ((regparm(0))) do_irq(int irq)
250 if (irq_table[irq].status & IRQ_DISABLED) {
257 if (NULL != irq_table[irq].handler) {
258 irq_handler_t *handler;
259 for (handler = irq_table[irq].handler;
260 NULL!= handler; handler = handler->next) {
261 handler->isr_func(handler->isr_data);
264 if ((irq & 7) != 7) {
265 printf("Spurious irq %d\n", irq);
273 void __attribute__ ((regparm(0))) unknown_exception_entry(int cause, int ip, int seg)
275 printf("Unknown Exception %d at %04x:%08x\n", cause, seg, ip);
278 void __attribute__ ((regparm(0))) divide_exception_entry(int cause, int ip, int seg)
280 printf("Divide Error (Division by zero) at %04x:%08x\n", seg, ip);
284 void __attribute__ ((regparm(0))) debug_exception_entry(int cause, int ip, int seg)
286 printf("Debug Interrupt (Single step) at %04x:%08x\n", seg, ip);
289 void __attribute__ ((regparm(0))) nmi_entry(int cause, int ip, int seg)
291 printf("NMI Interrupt at %04x:%08x\n", seg, ip);
294 void __attribute__ ((regparm(0))) invalid_instruction_entry(int cause, int ip, int seg)
296 printf("Invalid Instruction at %04x:%08x\n", seg, ip);
300 void __attribute__ ((regparm(0))) double_fault_entry(int cause, int ip, int seg)
302 printf("Double fault at %04x:%08x\n", seg, ip);
306 void __attribute__ ((regparm(0))) invalid_tss_exception_entry(int cause, int ip, int seg)
308 printf("Invalid TSS at %04x:%08x\n", seg, ip);
311 void __attribute__ ((regparm(0))) seg_fault_entry(int cause, int ip, int seg)
313 printf("Segmentation fault at %04x:%08x\n", seg, ip);
317 void __attribute__ ((regparm(0))) stack_fault_entry(int cause, int ip, int seg)
319 printf("Stack fault at %04x:%08x\n", seg, ip);
323 void __attribute__ ((regparm(0))) gpf_entry(int cause, int ip, int seg)
325 printf("General protection fault at %04x:%08x\n", seg, ip);
328 void __attribute__ ((regparm(0))) page_fault_entry(int cause, int ip, int seg)
330 printf("Page fault at %04x:%08x\n", seg, ip);
334 void __attribute__ ((regparm(0))) fp_exception_entry(int cause, int ip, int seg)
336 printf("Floating point exception at %04x:%08x\n", seg, ip);
339 void __attribute__ ((regparm(0))) alignment_check_entry(int cause, int ip, int seg)
341 printf("Alignment check at %04x:%08x\n", seg, ip);
344 void __attribute__ ((regparm(0))) machine_check_entry(int cause, int ip, int seg)
346 printf("Machine check exception at %04x:%08x\n", seg, ip);
350 void irq_install_handler(int ino, interrupt_handler_t *func, void *pdata)
358 if (NULL != irq_table[ino].handler) {
362 status = disable_interrupts();
363 irq_table[ino].handler = malloc(sizeof(irq_handler_t));
364 if (NULL == irq_table[ino].handler) {
368 memset(irq_table[ino].handler, 0, sizeof(irq_handler_t));
370 irq_table[ino].handler->isr_func = func;
371 irq_table[ino].handler->isr_data = pdata;
381 void irq_free_handler(int ino)
388 status = disable_interrupts();
390 if (NULL == irq_table[ino].handler) {
393 free(irq_table[ino].handler);
394 irq_table[ino].handler=NULL;
403 ".word 0x800\n" /* size of the table 8*256 bytes */
404 ".long idt\n" /* offset */
405 ".word 0x18\n");/* data segment */
407 static void set_vector(int intnum, void *routine)
409 idt[intnum].base_high = (u16)((u32)(routine)>>16);
410 idt[intnum].base_low = (u16)((u32)(routine)&0xffff);
414 int interrupt_init(void)
418 /* Just in case... */
419 disable_interrupts();
421 /* Initialize the IDT and stuff */
424 memset(irq_table, 0, sizeof(irq_table));
427 for (i=0;i<256;i++) {
428 idt[i].access = 0x8e;
430 idt[i].selector = 0x10;
431 set_vector(i, default_isr);
434 asm ("cs lidt idt_ptr\n");
436 /* Setup exceptions */
437 set_vector(0x00, exp_0);
438 set_vector(0x01, exp_1);
439 set_vector(0x02, exp_2);
440 set_vector(0x03, exp_3);
441 set_vector(0x04, exp_4);
442 set_vector(0x05, exp_5);
443 set_vector(0x06, exp_6);
444 set_vector(0x07, exp_7);
445 set_vector(0x08, exp_8);
446 set_vector(0x09, exp_9);
447 set_vector(0x0a, exp_10);
448 set_vector(0x0b, exp_11);
449 set_vector(0x0c, exp_12);
450 set_vector(0x0d, exp_13);
451 set_vector(0x0e, exp_14);
452 set_vector(0x0f, exp_15);
453 set_vector(0x10, exp_16);
454 set_vector(0x11, exp_17);
455 set_vector(0x12, exp_18);
456 set_vector(0x13, exp_19);
457 set_vector(0x14, exp_20);
458 set_vector(0x15, exp_21);
459 set_vector(0x16, exp_22);
460 set_vector(0x17, exp_23);
461 set_vector(0x18, exp_24);
462 set_vector(0x19, exp_25);
463 set_vector(0x1a, exp_26);
464 set_vector(0x1b, exp_27);
465 set_vector(0x1c, exp_28);
466 set_vector(0x1d, exp_29);
467 set_vector(0x1e, exp_30);
468 set_vector(0x1f, exp_31);
471 /* Setup interrupts */
472 set_vector(0x20, irq_0);
473 set_vector(0x21, irq_1);
474 set_vector(0x23, irq_3);
475 set_vector(0x24, irq_4);
476 set_vector(0x25, irq_5);
477 set_vector(0x26, irq_6);
478 set_vector(0x27, irq_7);
479 set_vector(0x28, irq_8);
480 set_vector(0x29, irq_9);
481 set_vector(0x2a, irq_10);
482 set_vector(0x2b, irq_11);
483 set_vector(0x2c, irq_12);
484 set_vector(0x2d, irq_13);
485 set_vector(0x2e, irq_14);
486 set_vector(0x2f, irq_15);
487 /* vectors 0x30-0x3f are reserved for irq 16-31 */
488 set_vector(0x40, syscall_entry);
491 /* Mask all interrupts */
492 outb(0xff, MASTER_PIC + IMR);
493 outb(0xff, SLAVE_PIC + IMR);
496 outb(ICW1_SEL|ICW1_EICW4, MASTER_PIC + ICW1);
497 outb(0x20, MASTER_PIC + ICW2); /* Place master PIC interrupts at INT20 */
498 outb(IR2, MASTER_PIC + ICW3); /* ICW3, One slevc PIC is present */
499 outb(ICW4_PM, MASTER_PIC + ICW4);
502 outb(OCW2_SEOI|i, MASTER_PIC + OCW2);
506 outb(ICW1_SEL|ICW1_EICW4, SLAVE_PIC + ICW1);
507 outb(0x28, SLAVE_PIC + ICW2); /* Place slave PIC interrupts at INT28 */
508 outb(0x02, SLAVE_PIC + ICW3); /* Slave ID */
509 outb(ICW4_PM, SLAVE_PIC + ICW4);
512 outb(OCW2_SEOI|i, SLAVE_PIC + OCW2);
516 /* enable cascade interrerupt */
517 outb(0xfb, MASTER_PIC + IMR);
518 outb(0xff, SLAVE_PIC + IMR);
520 /* It is now safe to enable interrupts */
526 void enable_interrupts(void)
531 int disable_interrupts(void)
535 asm volatile ("pushfl ; popl %0 ; cli\n" : "=g" (flags) : );
537 return (flags&0x200); /* IE flags is bit 9 */
541 #ifdef CFG_RESET_GENERIC
543 void __attribute__ ((regparm(0))) generate_gpf(void);
544 asm(".globl generate_gpf\n"
546 "ljmp $0x70, $0x47114711\n"); /* segment 0x70 is an arbitrary segment which does not
548 void reset_cpu(ulong addr)
550 set_vector(13, generate_gpf); /* general protection fault handler */
551 set_vector(8, generate_gpf); /* double fault handler */
552 generate_gpf(); /* start the show */