kernel: IRQs; PS/2 keyboard support

9 files changed, 198 insertions, 6 deletions

diff --git a/src/kernel/arch/i386/boot.c b/src/kernel/arch/i386/boot.c
index 94e9e2f..c25a848 100644
--- a/src/kernel/arch/i386/boot.c
+++ b/src/kernel/arch/i386/boot.c
@@ -3,6 +3,7 @@
 #include <kernel/arch/i386/boot.h>
 #include <kernel/arch/i386/gdt.h>
 #include <kernel/arch/i386/interrupts/idt.h>
+#include <kernel/arch/i386/interrupts/irq.h>
 #include <kernel/arch/i386/multiboot.h>
 #include <kernel/main.h>
 #include <kernel/panic.h>
@@ -16,6 +17,8 @@ void kmain_early(struct multiboot_info *multiboot) {
 	gdt_init();
 	tty_const("idt...");
 	idt_init();
+	tty_const("irq...");
+	irq_init();
 	tty_const("ata...");
 	ata_init();
 
diff --git a/src/kernel/arch/i386/interrupts/irq.c b/src/kernel/arch/i386/interrupts/irq.c
new file mode 100644
index 0000000..cb33bc8
--- /dev/null
+++ b/src/kernel/arch/i386/interrupts/irq.c
@@ -0,0 +1,41 @@
+#include <kernel/arch/i386/interrupts/irq.h>
+#include <kernel/arch/i386/port_io.h>
+#include <stdint.h>
+
+static const int PIC1 = 0x20;
+static const int PIC2 = 0xA0;
+
+static void irq_unmask(uint8_t line) {
+	uint16_t pic = line < 8 ? PIC1 : PIC2;
+	line &= 7;
+
+	port_out8(pic+1, port_in8(pic+1) & ~(1 << line));
+}
+
+void irq_init(void) {
+	port_out8(PIC1, 0x11);  /* start init sequence */
+	port_out8(PIC2, 0x11);
+
+	port_out8(PIC1+1, 0x20);   /* interrupt offsets */
+	port_out8(PIC2+1, 0x30);
+
+	port_out8(PIC1+1, 0x4);   /* just look at the osdev wiki lol */
+	port_out8(PIC2+1, 0x2);
+
+	port_out8(PIC1+1, 0x1);   /* 8086 mode */
+	port_out8(PIC2+1, 0x1);
+
+	port_out8(PIC1+1, 0xfd); /* mask */
+	port_out8(PIC2+1, 0xff);
+}
+
+void irq_eoi(uint8_t line) {
+	port_out8(PIC1, 0x20);
+	if (line >= 8)
+		port_out8(PIC2, 0x20);
+}
+
+void irq_interrupt_flag(bool flag) {
+	if (flag)	asm("sti" : : : "memory");
+	else		asm("cli" : : : "memory");
+}
diff --git a/src/kernel/arch/i386/interrupts/irq.h b/src/kernel/arch/i386/interrupts/irq.h
new file mode 100644
index 0000000..73d4af2
--- /dev/null
+++ b/src/kernel/arch/i386/interrupts/irq.h
@@ -0,0 +1,8 @@
+#pragma once
+#include <stdbool.h>
+#include <stdint.h>
+
+void irq_init(void);
+void irq_eoi(uint8_t line);
+
+void irq_interrupt_flag(bool flag);
diff --git a/src/kernel/arch/i386/interrupts/isr.c b/src/kernel/arch/i386/interrupts/isr.c
index 9d8bb6c..1448f44 100644
--- a/src/kernel/arch/i386/interrupts/isr.c
+++ b/src/kernel/arch/i386/interrupts/isr.c
@@ -1,4 +1,7 @@
+#include <kernel/arch/i386/interrupts/irq.h>
 #include <kernel/arch/i386/interrupts/isr.h>
+#include <kernel/arch/i386/port_io.h>
+#include <kernel/arch/i386/tty/keyboard.h>
 #include <kernel/arch/io.h>
 #include <kernel/panic.h>
 #include <kernel/proc.h>
@@ -16,6 +19,11 @@ void isr_stage3(int interrupt) {
 			isr_test_interrupt_called = true;
 			return;
 
+		case 0x21:; // keyboard irq
+			keyboard_recv(port_in8(0x60));
+			irq_eoi(1);
+			return;
+
 		default:
 			// TODO check if the exception was in the kernel
 			process_kill(process_current, interrupt);
diff --git a/src/kernel/arch/i386/tty/keyboard.c b/src/kernel/arch/i386/tty/keyboard.c
new file mode 100644
index 0000000..628c3a0
--- /dev/null
+++ b/src/kernel/arch/i386/tty/keyboard.c
@@ -0,0 +1,117 @@
+#include <kernel/arch/i386/tty/keyboard.h>
+
+static volatile bool keyboard_pressed = false;
+static volatile char keyboard_char;
+
+static bool keys[0x80] = {0};
+
+void keyboard_recv(char s) {
+	char c = 0, d = 0;
+	bool down = !(s & 0x80);
+	keys[s & 0x7f] = down;
+
+	switch (s & 0x7f) {
+		case 0x01:	/* esc */				break;
+		case 0x02:	c = '1';	d = '!';	break;
+		case 0x03:	c = '2';	d = '@';	break;
+		case 0x04:	c = '3';	d = '#';	break;
+		case 0x05:	c = '4';	d = '$';	break;
+		case 0x06:	c = '5';	d = '%';	break;
+		case 0x07:	c = '6';	d = '^';	break;
+		case 0x08:	c = '7';	d = '&';	break;
+		case 0x09:	c = '8';	d = '*';	break;
+		case 0x0A:	c = '9';	d = '(';	break;
+		case 0x0B:	c = '0';	d = ')';	break;
+		case 0x0C:	c = '-';	d = '_';	break;
+		case 0x0D:	c = '=';	d = '+';	break;
+		case 0x0E:	c = '\b';	d = '\b';	break;
+		case 0x0F:	c = '\t';	d = '\t';	break;
+		case 0x10:	c = 'q';	d = 'Q';	break;
+		case 0x11:	c = 'w';	d = 'W';	break;
+		case 0x12:	c = 'e';	d = 'E';	break;
+		case 0x13:	c = 'r';	d = 'R';	break;
+		case 0x14:	c = 't';	d = 'T';	break;
+		case 0x15:	c = 'y';	d = 'Y';	break;
+		case 0x16:	c = 'u';	d = 'U';	break;
+		case 0x17:	c = 'i';	d = 'I';	break;
+		case 0x18:	c = 'o';	d = 'O';	break;
+		case 0x19:	c = 'p';	d = 'P';	break;
+		case 0x1A:	c = '[';	d = '{';	break;
+		case 0x1B:	c = ']';	d = '}';	break;
+		case 0x1C:	c = '\r';	d = '\r';	break;
+		case 0x1D:	/*lctrl*/				break;
+		case 0x1E:	c = 'a';	d = 'A';	break;
+		case 0x1F:	c = 's';	d = 'S';	break;
+		case 0x20:	c = 'd';	d = 'D';	break;
+		case 0x21:	c = 'f';	d = 'F';	break;
+		case 0x22:	c = 'g';	d = 'G';	break;
+		case 0x23:	c = 'h';	d = 'H';	break;
+		case 0x24:	c = 'j';	d = 'J';	break;
+		case 0x25:	c = 'k';	d = 'K';	break;
+		case 0x26:	c = 'l';	d = 'L';	break;
+		case 0x27:	c = ';';	d = ':';	break;
+		case 0x28:	c = '\'';	d = '"';	break;
+		case 0x29:	c = '`';	d = '~';	break;
+		case 0x2A:	/*lshift */				break;
+		case 0x2B:	c = '\\';	d = '|';	break;
+		case 0x2C:	c = 'z';	d = 'Z';	break;
+		case 0x2D:	c = 'x';	d = 'X';	break;
+		case 0x2E:	c = 'c';	d = 'C';	break;
+		case 0x2F:	c = 'v';	d = 'V';	break;
+		case 0x30:	c = 'b';	d = 'B';	break;
+		case 0x31:	c = 'n';	d = 'N';	break;
+		case 0x32:	c = 'm';	d = 'M';	break;
+		case 0x33:	c = ',';	d = '<';	break;
+		case 0x34:	c = '.';	d = '>';	break;
+		case 0x35:	c = '/';	d = '?';	break;
+		case 0x36:	/*rshift*/				break;
+		case 0x38:	/*lalt*/				break;
+		case 0x39:	c = ' ';	d = ' ';	break;
+		case 0x3A:	/*caps*/	break;
+		case 0x3B:	/* F1 */	break;
+		case 0x3C:	/* F2 */	break;
+		case 0x3D:	/* F3 */	break;
+		case 0x3E:	/* F4 */	break;
+		case 0x3F:	/* F5 */	break;
+		case 0x40:	/* F6 */	break;
+		case 0x41:	/* F7 */	break;
+		case 0x42:	/* F8 */	break;
+		case 0x43:	/* F9 */	break;
+		case 0x44:	/* F10 */	break;
+		case 0x45:	/*numlock*/	break;
+		case 0x46:	/*scroll^*/	break;
+		case 0x57:	/* F11 */	break;
+		case 0x58:	/* F12 */	break;
+
+		/* keypad */
+		case 0x37:	c = '*';	d = '*';	break;
+		case 0x47:	c = '7';	d = '7';	break;
+		case 0x48:	c = '8';	d = '8';	break;
+		case 0x49:	c = '9';	d = '9';	break;
+		case 0x4A:	c = '-';	d = '-';	break;
+		case 0x4B:	c = '4';	d = '4';	break;
+		case 0x4C:	c = '5';	d = '5';	break;
+		case 0x4D:	c = '6';	d = '6';	break;
+		case 0x4E:	c = '+';	d = '+';	break;
+		case 0x4F:	c = '1';	d = '1';	break;
+		case 0x50:	c = '2';	d = '2';	break;
+		case 0x51:	c = '3';	d = '3';	break;
+		case 0x52:	c = '0';	d = '0';	break;
+		case 0x53:	c = '.';	d = '.';	break;
+	}
+
+	if (c && down) {
+		bool shift = keys[0x2A] || keys[0x36];
+		keyboard_pressed = true;
+		keyboard_char = shift ? d : c;
+	}
+}
+
+bool keyboard_poll_read(char *c) {
+	if (!keyboard_pressed) return false;
+	keyboard_pressed = false;
+	*c = keyboard_char;
+	return true;
+}
+
+
diff --git a/src/kernel/arch/i386/tty/keyboard.h b/src/kernel/arch/i386/tty/keyboard.h
new file mode 100644
index 0000000..8f2ebf2
--- /dev/null
+++ b/src/kernel/arch/i386/tty/keyboard.h
@@ -0,0 +1,5 @@
+#pragma once
+#include <stdbool.h>
+
+bool keyboard_poll_read(char *c);
+void keyboard_recv(char scancode);
diff --git a/src/kernel/arch/i386/tty/serial.c b/src/kernel/arch/i386/tty/serial.c
index f9bb252..e77ff5c 100644
--- a/src/kernel/arch/i386/tty/serial.c
+++ b/src/kernel/arch/i386/tty/serial.c
@@ -35,9 +35,11 @@ static void serial_putchar(char c) {
 	port_out8(COM1, c);
 }
 
-char serial_read(void) {
-	while ((port_in8(COM1 + 5) & 0x01) == 0); // wait for DR
-	return port_in8(COM1);
+bool serial_poll_read(char *c) {
+	if ((port_in8(COM1 + 5) & 0x01) == 0) // needs DR
+		return false;
+	*c = port_in8(COM1);
+	return true;
 }
 
 void serial_write(const char *buf, size_t len) {
diff --git a/src/kernel/arch/i386/tty/serial.h b/src/kernel/arch/i386/tty/serial.h
index 751e528..808f1aa 100644
--- a/src/kernel/arch/i386/tty/serial.h
+++ b/src/kernel/arch/i386/tty/serial.h
@@ -1,6 +1,7 @@
 #pragma once
+#include <stdbool.h>
 #include <stddef.h>
 
-char serial_read(void);
+bool serial_poll_read(char *c);
 void serial_write(const char *buf, size_t len);
 void serial_init(void);
diff --git a/src/kernel/arch/i386/tty/tty.c b/src/kernel/arch/i386/tty/tty.c
index 5a65221..f3fecf3 100644
--- a/src/kernel/arch/i386/tty/tty.c
+++ b/src/kernel/arch/i386/tty/tty.c
@@ -1,3 +1,5 @@
+#include <kernel/arch/i386/interrupts/irq.h>
+#include <kernel/arch/i386/tty/keyboard.h>
 #include <kernel/arch/i386/tty/serial.h>
 #include <kernel/arch/i386/tty/vga.h>
 #include <kernel/arch/io.h>
@@ -12,8 +14,13 @@ void tty_init(void) {
 }
 
 void tty_read(char *buf, size_t len) {
-	for (size_t i = 0; i < len; i++)
-		buf[i] = serial_read();
+	irq_interrupt_flag(true);
+	for (size_t i = 0; i < len; i++) {
+		for (;;) {
+			if (serial_poll_read(&buf[i]))		break;
+			if (keyboard_poll_read(&buf[i]))	break;
+		}
+	}
 }
 
 void tty_write(const char *buf, size_t len) {