Files
jsix/src/kernel/interrupts.cpp
Justin C. Miller 25b9625635 paging finally works
2018-04-25 19:53:22 -07:00

358 lines
7.8 KiB
C++

#include <stddef.h>
#include <stdint.h>
#include "kutil/memory.h"
#include "console.h"
#include "interrupts.h"
enum class gdt_flags : uint8_t
{
ac = 0x01,
rw = 0x02,
dc = 0x04,
ex = 0x08,
r1 = 0x20,
r2 = 0x40,
r3 = 0x60,
pr = 0x80,
res_1 = 0x10
};
inline gdt_flags
operator | (gdt_flags lhs, gdt_flags rhs)
{
return static_cast<gdt_flags>(
static_cast<uint8_t>(lhs) | static_cast<uint8_t>(rhs));
}
struct gdt_descriptor
{
uint16_t limit_low;
uint16_t base_low;
uint8_t base_mid;
uint8_t flags;
uint8_t granularity;
uint8_t base_high;
} __attribute__ ((packed));
struct idt_descriptor
{
uint16_t base_low;
uint16_t selector;
uint8_t ist;
uint8_t flags;
uint16_t base_mid;
uint32_t base_high;
uint32_t reserved; // must be zero
} __attribute__ ((packed));
struct table_ptr
{
uint16_t limit;
uint64_t base;
} __attribute__ ((packed));
gdt_descriptor g_gdt_table[10];
idt_descriptor g_idt_table[256];
table_ptr g_gdtr;
table_ptr g_idtr;
struct registers;
extern "C" {
void idt_write();
void idt_load();
void gdt_write();
void gdt_load();
void isr_handler(registers);
void irq_handler(registers);
#define ISR(i, name) extern void name ()
#define EISR(i, name) extern void name ()
#define IRQ(i, q, name) extern void name ()
#include "interrupt_isrs.inc"
#undef IRQ
#undef EISR
#undef ISR
}
void idt_dump(const table_ptr &table);
void gdt_dump(const table_ptr &table);
void
set_gdt_entry(uint8_t i, uint32_t base, uint32_t limit, bool is64, gdt_flags flags)
{
g_gdt_table[i].limit_low = limit & 0xffff;
g_gdt_table[i].base_low = base & 0xffff;
g_gdt_table[i].base_mid = (base >> 16) & 0xff;
g_gdt_table[i].base_high = (base >> 24) & 0xff;
g_gdt_table[i].granularity =
((limit >> 16) & 0xf) | (is64 ? 0xa0 : 0xc0);
g_gdt_table[i].flags = static_cast<uint8_t>(flags | gdt_flags::res_1 | gdt_flags::pr);
}
void
set_idt_entry(uint8_t i, uint64_t addr, uint16_t selector, uint8_t flags)
{
g_idt_table[i].base_low = addr & 0xffff;
g_idt_table[i].base_mid = (addr >> 16) & 0xffff;
g_idt_table[i].base_high = (addr >> 32) & 0xffffffff;
g_idt_table[i].selector = selector;
g_idt_table[i].flags = flags;
g_idt_table[i].ist = 0;
g_idt_table[i].reserved = 0;
}
void
interrupts_init()
{
kutil::memset(&g_gdt_table, 0, sizeof(g_gdt_table));
kutil::memset(&g_idt_table, 0, sizeof(g_idt_table));
g_gdtr.limit = sizeof(g_gdt_table) - 1;
g_gdtr.base = reinterpret_cast<uint64_t>(&g_gdt_table);
set_gdt_entry(1, 0, 0xfffff, false, gdt_flags::rw);
set_gdt_entry(2, 0, 0xfffff, false, gdt_flags::rw | gdt_flags::ex | gdt_flags::dc);
set_gdt_entry(3, 0, 0xfffff, false, gdt_flags::rw);
set_gdt_entry(4, 0, 0xfffff, false, gdt_flags::rw | gdt_flags::ex);
set_gdt_entry(6, 0, 0xfffff, false, gdt_flags::rw);
set_gdt_entry(7, 0, 0xfffff, true, gdt_flags::rw | gdt_flags::ex);
gdt_write();
g_idtr.limit = sizeof(g_idt_table) - 1;
g_idtr.base = reinterpret_cast<uint64_t>(&g_idt_table);
#define ISR(i, name) set_idt_entry(i, reinterpret_cast<uint64_t>(& name), 0x38, 0x8e);
#define EISR(i, name) set_idt_entry(i, reinterpret_cast<uint64_t>(& name), 0x38, 0x8e);
#define IRQ(i, q, name) set_idt_entry(i, reinterpret_cast<uint64_t>(& name), 0x38, 0x8e);
#include "interrupt_isrs.inc"
#undef IRQ
#undef EISR
#undef ISR
idt_write();
}
struct registers
{
uint64_t ds;
uint64_t rdi, rsi, rbp, rsp, rbx, rdx, rcx, rax;
uint64_t interrupt, errorcode;
uint64_t rip, cs, eflags, user_esp, ss;
};
#define print_reg(name, value) \
cons->puts(" " name ": "); \
cons->put_hex((value)); \
cons->puts("\n");
void
isr_handler(registers regs)
{
console *cons = console::get();
cons->puts("received ISR interrupt:\n");
uint64_t cr2 = 0;
__asm__ __volatile__ ("mov %%cr2, %0" : "=r"(cr2));
print_reg("ISR", regs.interrupt);
print_reg("ERR", regs.errorcode);
print_reg("CR2", cr2);
console::get()->puts("\n");
print_reg(" ds", regs.ds);
print_reg("rdi", regs.rdi);
print_reg("rsi", regs.rsi);
print_reg("rbp", regs.rbp);
print_reg("rsp", regs.rsp);
print_reg("rbx", regs.rbx);
print_reg("rdx", regs.rdx);
print_reg("rcx", regs.rcx);
print_reg("rax", regs.rax);
console::get()->puts("\n");
print_reg("rip", regs.rip);
print_reg(" cs", regs.cs);
print_reg(" ef", regs.eflags);
print_reg("esp", regs.user_esp);
print_reg(" ss", regs.ss);
while(1) asm("hlt");
}
void
irq_handler(registers regs)
{
console *cons = console::get();
cons->puts("received IRQ interrupt:\n");
print_reg("ISR", regs.interrupt);
print_reg("ERR", regs.errorcode);
console::get()->puts("\n");
print_reg(" ds", regs.ds);
print_reg("rdi", regs.rdi);
print_reg("rsi", regs.rsi);
print_reg("rbp", regs.rbp);
print_reg("rsp", regs.rsp);
print_reg("rbx", regs.rbx);
print_reg("rdx", regs.rdx);
print_reg("rcx", regs.rcx);
print_reg("rax", regs.rax);
console::get()->puts("\n");
print_reg("rip", regs.rip);
print_reg(" cs", regs.cs);
print_reg(" ef", regs.eflags);
print_reg("esp", regs.user_esp);
print_reg(" ss", regs.ss);
while(1) asm("hlt");
}
void
gdt_dump(const table_ptr &table)
{
console *cons = console::get();
cons->puts("Loaded GDT at: ");
cons->put_hex(table.base);
cons->puts(" size: ");
cons->put_dec(table.limit + 1);
cons->puts(" bytes\n");
int count = (table.limit + 1) / sizeof(gdt_descriptor);
const gdt_descriptor *gdt =
reinterpret_cast<const gdt_descriptor *>(table.base);
for (int i = 0; i < count; ++i) {
uint32_t base =
(gdt[i].base_high << 24) |
(gdt[i].base_mid << 16) |
gdt[i].base_low;
uint32_t limit =
static_cast<uint32_t>(gdt[i].granularity & 0x0f) << 16 |
gdt[i].limit_low;
cons->puts(" Entry ");
cons->put_dec(i);
cons->puts(": Base ");
cons->put_hex(base);
cons->puts(" Limit ");
cons->put_hex(limit);
cons->puts(" Privs ");
cons->put_dec((gdt[i].flags >> 5) & 0x03);
cons->puts(" Flags ");
if (gdt[i].flags & 0x80) {
cons->puts("P ");
if (gdt[i].flags & 0x08)
cons->puts("EX ");
else
cons->puts(" ");
if (gdt[i].flags & 0x04)
cons->puts("DC ");
else
cons->puts(" ");
if (gdt[i].flags & 0x02)
cons->puts("RW ");
else
cons->puts(" ");
if (gdt[i].granularity & 0x80)
cons->puts("KB ");
else
cons->puts(" B ");
if ((gdt[i].granularity & 0x60) == 0x20)
cons->puts("64");
else if ((gdt[i].granularity & 0x60) == 0x40)
cons->puts("32");
else
cons->puts("16");
}
cons->puts("\n");
}
}
void
idt_dump(const table_ptr &table)
{
console *cons = console::get();
cons->puts("Loaded IDT at: ");
cons->put_hex(table.base);
cons->puts(" size: ");
cons->put_dec(table.limit + 1);
cons->puts(" bytes\n");
int count = (table.limit + 1) / sizeof(idt_descriptor);
const idt_descriptor *idt =
reinterpret_cast<const idt_descriptor *>(table.base);
if (count > 32) count = 32;
for (int i = 0; i < count; ++i) {
uint64_t base =
(static_cast<uint64_t>(idt[i].base_high) << 32) |
(static_cast<uint64_t>(idt[i].base_mid) << 16) |
idt[i].base_low;
cons->puts(" Entry ");
cons->put_dec(i);
cons->puts(": Base ");
cons->put_hex(base);
cons->puts(" Sel(");
cons->put_dec(idt[i].selector & 0x3);
cons->puts(",");
cons->put_dec((idt[i].selector & 0x4) >> 2);
cons->puts(",");
cons->put_dec(idt[i].selector >> 3);
cons->puts(") ");
cons->puts("IST ");
cons->put_dec(idt[i].ist);
switch (idt[i].flags & 0xf) {
case 0x5: cons->puts(" 32tsk "); break;
case 0x6: cons->puts(" 16int "); break;
case 0x7: cons->puts(" 16trp "); break;
case 0xe: cons->puts(" 32int "); break;
case 0xf: cons->puts(" 32trp "); break;
default:
cons->puts(" ?");
cons->put_hex(idt[i].flags & 0xf);
cons->puts(" ");
break;
}
cons->puts("DPL ");
cons->put_dec((idt[i].flags >> 5) & 0x3);
if (idt[i].flags & 0x80)
cons->puts(" P");
cons->puts("\n");
}
}