inmates/lib/x86/int.c

   1 /*
   2  * Jailhouse, a Linux-based partitioning hypervisor
   3  *
   4  * Copyright (c) Siemens AG, 2014
   5  *
   6  * Authors:
   7  *  Jan Kiszka <jan.kiszka@siemens.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  */
  12
  13 #include <inmate.h>
  14
  15 #define NUM_IDT_DESC            64
  16
  17 #define X2APIC_EOI              0x80b
  18 #define X2APIC_SPIV             0x80f
  19
  20 #define APIC_EOI_ACK            0
  21
  22 struct desc_table_reg {
  23         u16 limit;
  24         u64 base;
  25 } __attribute__((packed));
  26
  27 static u32 idt[NUM_IDT_DESC * 4];
  28 static int_handler_t int_handler[NUM_IDT_DESC];
  29
  30 extern u8 irq_entry[];
  31
  32 static inline void write_idtr(struct desc_table_reg *val)
  33 {
  34         asm volatile("lidt %0" : : "m" (*val));
  35 }
  36
  37 void int_init(void)
  38 {
  39         struct desc_table_reg dtr;
  40
  41         write_msr(X2APIC_SPIV, 0x1ff);
  42
  43         dtr.limit = NUM_IDT_DESC * 16 - 1;
  44         dtr.base = (u64)&idt;
  45         write_idtr(&dtr);
  46 }
  47
  48 static void __attribute__((used)) handle_interrupt(unsigned int vector)
  49 {
  50         int_handler[vector]();
  51         write_msr(X2APIC_EOI, APIC_EOI_ACK);
  52 }
  53
  54 void int_set_handler(unsigned int vector, int_handler_t handler)
  55 {
  56         unsigned long entry = (unsigned long)irq_entry + vector * 16;
  57
  58         int_handler[vector] = handler;
  59
  60         idt[vector * 4] = (entry & 0xffff) | (INMATE_CS64 << 16);
  61         idt[vector * 4 + 1] = 0x8e00 | (entry & 0xffff0000);
  62         idt[vector * 4 + 2] = entry >> 32;
  63 }
  64
  65 #ifdef __x86_64__
  66 asm(
  67 ".macro irq_prologue vector\n\t"
  68         "push %rdi\n\t"
  69         "mov $vector,%rdi\n\t"
  70         "jmp irq_common\n"
  71 ".endm\n\t"
  72
  73         ".global irq_entry\n\t"
  74         ".balign 16\n"
  75 "irq_entry:\n"
  76 "vector=0\n"
  77 ".rept 64\n"
  78         "irq_prologue vector\n\t"
  79         "vector=vector+1\n\t"
  80         ".balign 16\n\t"
  81 ".endr\n"
  82
  83 "irq_common:\n\t"
  84         "push %rax\n\t"
  85         "push %rcx\n\t"
  86         "push %rdx\n\t"
  87         "push %rsi\n\t"
  88         "push %r8\n\t"
  89         "push %r9\n\t"
  90         "push %r10\n\t"
  91         "push %r11\n\t"
  92
  93         "call handle_interrupt\n\t"
  94
  95         "pop %r11\n\t"
  96         "pop %r10\n\t"
  97         "pop %r9\n\t"
  98         "pop %r8\n\t"
  99         "pop %rsi\n\t"
 100         "pop %rdx\n\t"
 101         "pop %rcx\n\t"
 102         "pop %rax\n\t"
 103         "pop %rdi\n\t"
 104
 105         "iretq"
 106 );
 107 #else
 108 #error implement me!
 109 #endif