2 * GeekOS interrupt handling data structures and functions
3 * Copyright (c) 2001,2003 David H. Hovemeyer <daveho@cs.umd.edu>
6 * This is free software. You are permitted to use,
7 * redistribute, and modify it as specified in the file "COPYING".
10 #include <geekos/idt.h> /* x86-specific int handling stuff */
11 #include <geekos/screen.h>
12 #include <geekos/kassert.h>
13 #include <geekos/int.h>
14 #include <geekos/serial.h>
15 #include <geekos/debug.h>
17 #include <geekos/cpu.h>
20 * Defined in lowlevel.asm.
22 ulong_t Get_Current_EFLAGS(void);
24 /* ----------------------------------------------------------------------
25 * Private functions and data
26 * ---------------------------------------------------------------------- */
39 char *exception_names[] = {
45 "#BR (BOUND Range Exceeded)",
46 "#UD (Invalid Opcode)",
47 "#NM (No Math Coprocessor)",
49 "Coprocessor Segment Overrun",
51 "#NP (Segment Not Present)",
52 "#SS (Stack Segment Fault)",
53 "#GP (General Protection Fault)",
56 "#MF (Math Fault x87)",
57 "#AC (Alignment Check)",
58 "#MC (Machine Check)",
59 "#XF (SIMD FP Exception)",
298 char *exception_type_names[] = {
299 "External Interrupt",
302 "Hardware Exception",
305 "Software Exception",
313 * A dummy interrupt handler function.
314 * Ensures that the low-level interrupt code always
315 * has a handler to call.
317 static void Dummy_Interrupt_Handler(struct Interrupt_State* state)
321 Print("Unexpected Interrupt! Ignoring!\n");
322 SerialPrint("*** Unexpected interrupt! *** Ignoring!\n");
323 Dump_Interrupt_State(state);
324 // SerialPrint_VMCS_ALL();
332 static void Print_Selector(const char* regName, uint_t value)
334 Print("%s: index=%d, ti=%d, rpl=%d\n",
335 regName, value >> 3, (value >> 2) & 1, value & 3);
339 static void SerialPrint_Selector(const char* regName, uint_t value)
341 SerialPrint("%s: index=%d, ti=%d, rpl=%d\n",
342 regName, value >> 3, (value >> 2) & 1, value & 3);
345 /* ----------------------------------------------------------------------
347 * ---------------------------------------------------------------------- */
350 * Initialize the interrupt system.
352 void Init_Interrupts(void)
356 PrintBoth("Initializing Interrupts\n");
358 /* Low-level initialization. Build and initialize the IDT. */
362 * Initialize all entries of the handler table with a dummy handler.
363 * This will ensure that we always have a handler function to call.
365 for (i = 0; i < NUM_IDT_ENTRIES; ++i) {
366 Install_Interrupt_Handler(i, Dummy_Interrupt_Handler);
373 /* Re-enable interrupts */
378 * Query whether or not interrupts are currently enabled.
380 bool Interrupts_Enabled(void)
382 ulong_t eflags = Get_Current_EFLAGS();
383 return (eflags & EFLAGS_IF) != 0;
387 * Dump interrupt state struct to screen
389 void Dump_Interrupt_State(struct Interrupt_State* state)
391 uint_t errorCode = state->errorCode;
393 Print("eax=%08x ebx=%08x ecx=%08x edx=%08x\n"
394 "esi=%08x edi=%08x ebp=%08x\n"
395 "eip=%08x cs=%08x eflags=%08x\n"
396 "Interrupt number=%d (%s), error code=%d\n"
397 "index=%d, TI=%d, IDT=%d, EXT=%d\n",
398 state->eax, state->ebx, state->ecx, state->edx,
399 state->esi, state->edi, state->ebp,
400 state->eip, state->cs, state->eflags,
401 state->intNum, exception_names[state->intNum], errorCode,
402 errorCode >> 3, (errorCode >> 2) & 1, (errorCode >> 1) & 1, errorCode & 1
406 if (Is_User_Interrupt(state)) {
407 struct User_Interrupt_State *ustate = (struct User_Interrupt_State*) state;
408 SerialPrint("user esp=%08x, user ss=%08x\n", ustate->espUser, ustate->ssUser);
410 SerialPrint_Selector("cs", state->cs);
411 SerialPrint_Selector("ds", state->ds);
412 SerialPrint_Selector("es", state->es);
413 SerialPrint_Selector("fs", state->fs);
414 SerialPrint_Selector("gs", state->gs);