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lesson 23, step 3

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This commit is contained in:
Carlos
2015-08-18 10:31:28 +02:00
parent 92ff191c3d
commit de3d442569
18 changed files with 124 additions and 127 deletions
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5
23-fixes/cpu/idt.c
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@@ -1,6 +1,7 @@
#include "idt.h"
#include "type.h"
void set_idt_gate(int n, u32 handler) {
void set_idt_gate(int n, uint32_t handler) {
idt[n].low_offset = low_16(handler);
idt[n].sel = KERNEL_CS;
idt[n].always0 = 0;
@@ -9,7 +10,7 @@ void set_idt_gate(int n, u32 handler) {
}
void set_idt() {
idt_reg.base = (u32) &idt;
idt_reg.base = (uint32_t) &idt;
idt_reg.limit = IDT_ENTRIES * sizeof(idt_gate_t) - 1;
/* Don't make the mistake of loading &idt -- always load &idt_reg */
__asm__ __volatile__("lidtl (%0)" : : "r" (&idt_reg));

18
23-fixes/cpu/idt.h
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@@ -1,30 +1,30 @@
#ifndef IDT_H
#define IDT_H
#include "type.h"
#include <stdint.h>
/* Segment selectors */
#define KERNEL_CS 0x08
/* How every interrupt gate (handler) is defined */
typedef struct {
u16 low_offset; /* Lower 16 bits of handler function address */
u16 sel; /* Kernel segment selector */
u8 always0;
uint16_t low_offset; /* Lower 16 bits of handler function address */
uint16_t sel; /* Kernel segment selector */
uint8_t always0;
/* First byte
* Bit 7: "Interrupt is present"
* Bits 6-5: Privilege level of caller (0=kernel..3=user)
* Bit 4: Set to 0 for interrupt gates
* Bits 3-0: bits 1110 = decimal 14 = "32 bit interrupt gate" */
u8 flags;
u16 high_offset; /* Higher 16 bits of handler function address */
uint8_t flags;
uint16_t high_offset; /* Higher 16 bits of handler function address */
} __attribute__((packed)) idt_gate_t ;
/* A pointer to the array of interrupt handlers.
* Assembly instruction 'lidt' will read it */
typedef struct {
u16 limit;
u32 base;
uint16_t limit;
uint32_t base;
} __attribute__((packed)) idt_register_t;
#define IDT_ENTRIES 256
@@ -33,7 +33,7 @@ idt_register_t idt_reg;
/* Functions implemented in idt.c */
void set_idt_gate(int n, u32 handler);
void set_idt_gate(int n, uint32_t handler);
void set_idt();
#endif

98
23-fixes/cpu/isr.c
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@@ -11,38 +11,38 @@ isr_t interrupt_handlers[256];
/* Can't do this with a loop because we need the address
* of the function names */
void isr_install() {
set_idt_gate(0, (u32)isr0);
set_idt_gate(1, (u32)isr1);
set_idt_gate(2, (u32)isr2);
set_idt_gate(3, (u32)isr3);
set_idt_gate(4, (u32)isr4);
set_idt_gate(5, (u32)isr5);
set_idt_gate(6, (u32)isr6);
set_idt_gate(7, (u32)isr7);
set_idt_gate(8, (u32)isr8);
set_idt_gate(9, (u32)isr9);
set_idt_gate(10, (u32)isr10);
set_idt_gate(11, (u32)isr11);
set_idt_gate(12, (u32)isr12);
set_idt_gate(13, (u32)isr13);
set_idt_gate(14, (u32)isr14);
set_idt_gate(15, (u32)isr15);
set_idt_gate(16, (u32)isr16);
set_idt_gate(17, (u32)isr17);
set_idt_gate(18, (u32)isr18);
set_idt_gate(19, (u32)isr19);
set_idt_gate(20, (u32)isr20);
set_idt_gate(21, (u32)isr21);
set_idt_gate(22, (u32)isr22);
set_idt_gate(23, (u32)isr23);
set_idt_gate(24, (u32)isr24);
set_idt_gate(25, (u32)isr25);
set_idt_gate(26, (u32)isr26);
set_idt_gate(27, (u32)isr27);
set_idt_gate(28, (u32)isr28);
set_idt_gate(29, (u32)isr29);
set_idt_gate(30, (u32)isr30);
set_idt_gate(31, (u32)isr31);
set_idt_gate(0, (uint32_t)isr0);
set_idt_gate(1, (uint32_t)isr1);
set_idt_gate(2, (uint32_t)isr2);
set_idt_gate(3, (uint32_t)isr3);
set_idt_gate(4, (uint32_t)isr4);
set_idt_gate(5, (uint32_t)isr5);
set_idt_gate(6, (uint32_t)isr6);
set_idt_gate(7, (uint32_t)isr7);
set_idt_gate(8, (uint32_t)isr8);
set_idt_gate(9, (uint32_t)isr9);
set_idt_gate(10, (uint32_t)isr10);
set_idt_gate(11, (uint32_t)isr11);
set_idt_gate(12, (uint32_t)isr12);
set_idt_gate(13, (uint32_t)isr13);
set_idt_gate(14, (uint32_t)isr14);
set_idt_gate(15, (uint32_t)isr15);
set_idt_gate(16, (uint32_t)isr16);
set_idt_gate(17, (uint32_t)isr17);
set_idt_gate(18, (uint32_t)isr18);
set_idt_gate(19, (uint32_t)isr19);
set_idt_gate(20, (uint32_t)isr20);
set_idt_gate(21, (uint32_t)isr21);
set_idt_gate(22, (uint32_t)isr22);
set_idt_gate(23, (uint32_t)isr23);
set_idt_gate(24, (uint32_t)isr24);
set_idt_gate(25, (uint32_t)isr25);
set_idt_gate(26, (uint32_t)isr26);
set_idt_gate(27, (uint32_t)isr27);
set_idt_gate(28, (uint32_t)isr28);
set_idt_gate(29, (uint32_t)isr29);
set_idt_gate(30, (uint32_t)isr30);
set_idt_gate(31, (uint32_t)isr31);
// Remap the PIC
port_byte_out(0x20, 0x11);
@@ -57,22 +57,22 @@ void isr_install() {
port_byte_out(0xA1, 0x0);
// Install the IRQs
set_idt_gate(32, (u32)irq0);
set_idt_gate(33, (u32)irq1);
set_idt_gate(34, (u32)irq2);
set_idt_gate(35, (u32)irq3);
set_idt_gate(36, (u32)irq4);
set_idt_gate(37, (u32)irq5);
set_idt_gate(38, (u32)irq6);
set_idt_gate(39, (u32)irq7);
set_idt_gate(40, (u32)irq8);
set_idt_gate(41, (u32)irq9);
set_idt_gate(42, (u32)irq10);
set_idt_gate(43, (u32)irq11);
set_idt_gate(44, (u32)irq12);
set_idt_gate(45, (u32)irq13);
set_idt_gate(46, (u32)irq14);
set_idt_gate(47, (u32)irq15);
set_idt_gate(32, (uint32_t)irq0);
set_idt_gate(33, (uint32_t)irq1);
set_idt_gate(34, (uint32_t)irq2);
set_idt_gate(35, (uint32_t)irq3);
set_idt_gate(36, (uint32_t)irq4);
set_idt_gate(37, (uint32_t)irq5);
set_idt_gate(38, (uint32_t)irq6);
set_idt_gate(39, (uint32_t)irq7);
set_idt_gate(40, (uint32_t)irq8);
set_idt_gate(41, (uint32_t)irq9);
set_idt_gate(42, (uint32_t)irq10);
set_idt_gate(43, (uint32_t)irq11);
set_idt_gate(44, (uint32_t)irq12);
set_idt_gate(45, (uint32_t)irq13);
set_idt_gate(46, (uint32_t)irq14);
set_idt_gate(47, (uint32_t)irq15);
set_idt(); // Load with ASM
}
@@ -126,7 +126,7 @@ void isr_handler(registers_t r) {
kprint("\n");
}
void register_interrupt_handler(u8 n, isr_t handler) {
void register_interrupt_handler(uint8_t n, isr_t handler) {
interrupt_handlers[n] = handler;
}

12
23-fixes/cpu/isr.h
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@@ -1,7 +1,7 @@
#ifndef ISR_H
#define ISR_H
#include "type.h"
#include <stdint.h>
/* ISRs reserved for CPU exceptions */
extern void isr0();
@@ -73,10 +73,10 @@ extern void irq15();
/* Struct which aggregates many registers */
typedef struct {
u32 ds; /* Data segment selector */
u32 edi, esi, ebp, esp, ebx, edx, ecx, eax; /* Pushed by pusha. */
u32 int_no, err_code; /* Interrupt number and error code (if applicable) */
u32 eip, cs, eflags, useresp, ss; /* Pushed by the processor automatically */
uint32_t ds; /* Data segment selector */
uint32_t edi, esi, ebp, esp, ebx, edx, ecx, eax; /* Pushed by pusha. */
uint32_t int_no, err_code; /* Interrupt number and error code (if applicable) */
uint32_t eip, cs, eflags, useresp, ss; /* Pushed by the processor automatically */
} registers_t;
void isr_install();
@@ -84,6 +84,6 @@ void isr_handler(registers_t r);
void irq_install();
typedef void (*isr_t)(registers_t);
void register_interrupt_handler(u8 n, isr_t handler);
void register_interrupt_handler(uint8_t n, isr_t handler);
#endif

12
23-fixes/cpu/ports.c
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@@ -3,8 +3,8 @@
/**
* Read a byte from the specified port
*/
u8 port_byte_in (u16 port) {
u8 result;
uint8_t port_byte_in (uint16_t port) {
uint8_t result;
/* Inline assembler syntax
* !! Notice how the source and destination registers are switched from NASM !!
*
@@ -17,7 +17,7 @@ u8 port_byte_in (u16 port) {
return result;
}
void port_byte_out (u16 port, u8 data) {
void port_byte_out (uint16_t port, uint8_t data) {
/* Notice how here both registers are mapped to C variables and
* nothing is returned, thus, no equals '=' in the asm syntax
* However we see a comma since there are two variables in the input area
@@ -26,12 +26,12 @@ void port_byte_out (u16 port, u8 data) {
__asm__ __volatile__("out %%al, %%dx" : : "a" (data), "d" (port));
}
u16 port_word_in (u16 port) {
u16 result;
uint16_t port_word_in (uint16_t port) {
uint16_t result;
__asm__("in %%dx, %%ax" : "=a" (result) : "d" (port));
return result;
}
void port_word_out (u16 port, u16 data) {
void port_word_out (uint16_t port, uint16_t data) {
__asm__ __volatile__("out %%ax, %%dx" : : "a" (data), "d" (port));
}

10
23-fixes/cpu/ports.h
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@@ -1,11 +1,11 @@
#ifndef PORTS_H
#define PORTS_H
#include "../cpu/type.h"
#include <stdint.h>
unsigned char port_byte_in (u16 port);
void port_byte_out (u16 port, u8 data);
unsigned short port_word_in (u16 port);
void port_word_out (u16 port, u16 data);
unsigned char port_byte_in (uint16_t port);
void port_byte_out (uint16_t port, uint8_t data);
unsigned short port_word_in (uint16_t port);
void port_word_out (uint16_t port, uint16_t data);
#endif

10
23-fixes/cpu/timer.c
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@@ -3,21 +3,21 @@
#include "ports.h"
#include "../libc/function.h"
u32 tick = 0;
uint32_t tick = 0;
static void timer_callback(registers_t regs) {
tick++;
UNUSED(regs);
}
void init_timer(u32 freq) {
void init_timer(uint32_t freq) {
/* Install the function we just wrote */
register_interrupt_handler(IRQ0, timer_callback);
/* Get the PIT value: hardware clock at 1193180 Hz */
u32 divisor = 1193180 / freq;
u8 low = (u8)(divisor & 0xFF);
u8 high = (u8)( (divisor >> 8) & 0xFF);
uint32_t divisor = 1193180 / freq;
uint8_t low = (uint8_t)(divisor & 0xFF);
uint8_t high = (uint8_t)( (divisor >> 8) & 0xFF);
/* Send the command */
port_byte_out(0x43, 0x36); /* Command port */
port_byte_out(0x40, low);

4
23-fixes/cpu/timer.h
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@@ -1,8 +1,8 @@
#ifndef TIMER_H
#define TIMER_H
#include "type.h"
#include <stdint.h>
void init_timer(u32 freq);
void init_timer(uint32_t freq);
#endif

13
23-fixes/cpu/type.h
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@@ -1,16 +1,9 @@
#ifndef TYPE_H
#define TYPE_H
/* Instead of using 'chars' to allocate non-character bytes,
* we will use these new type with no semantic meaning */
typedef unsigned int u32;
typedef int s32;
typedef unsigned short u16;
typedef short s16;
typedef unsigned char u8;
typedef char s8;
#include <stdint.h>
#define low_16(address) (u16)((address) & 0xFFFF)
#define high_16(address) (u16)(((address) >> 16) & 0xFFFF)
#define low_16(address) (uint16_t)((address) & 0xFFFF)
#define high_16(address) (uint16_t)(((address) >> 16) & 0xFFFF)
#endif