Add reboot functionality

common/acpi.c

@@ -752,4 +752,8 @@ void acpi_power_off(void) {
     AcpiEnterSleepState(ACPI_STATE_S5);
     panic("Power Off");
 }
+
+void acpi_reboot(void) {
+    AcpiReset();
+}
 #endif /* KTF_ACPICA */

common/cmdline.c

@@ -73,6 +73,9 @@ string_cmd("com4", opt_com4);
 bool opt_fb_scroll = true;
 bool_cmd("fb_scroll", opt_fb_scroll);
 
+unsigned long opt_reboot_timeout = 0; /* Disabled by default */
+ulong_cmd("reboot_timeout", opt_reboot_timeout);
+
 const char *kernel_cmdline;
 
 void __text_init cmdline_parse(const char *cmdline) {

common/kernel.c

@@ -31,14 +31,34 @@
 #include <percpu.h>
 #include <sched.h>
 #include <setup.h>
+#include <time.h>
 #ifdef KTF_PMU
 #include <perfmon/pfmlib.h>
 #endif
 
+void reboot(void) {
+    printk("Rebooting...\n");
+    io_delay();
+
+#ifdef KTF_ACPICA
+    acpi_reboot();
+#endif
+    keyboard_reboot();
+    hard_reboot();
+}
+
 static void __noreturn echo_loop(void) {
+    time_t reboot_timeout = opt_reboot_timeout * 1000; /* ms */
+    time_t start_time = get_timer_ticks();
+
     while (1) {
         io_delay();
         keyboard_process_keys();
+
+        if (reboot_timeout > 0) {
+            if (get_timer_ticks() - start_time >= reboot_timeout)
+                reboot();
+        }
     }
 }
 

drivers/keyboard.c

@@ -61,12 +61,28 @@ struct keyboard_state {
 typedef struct keyboard_state keyboard_state_t;
 
 static keyboard_state_t keyboard_state;
+static bool i8042_present = false;
+
+void keyboard_reboot(void) {
+    if (!i8042_present)
+        return;
+
+    cli();
+
+    while ((inb(KEYBOARD_PORT_CMD) & KEYBOARD_STATUS_IN_FULL) != 0)
+        cpu_relax();
+
+    outb(KEYBOARD_PORT_CMD, KEYBOARD_RESET_CMD);
+    halt();
+}
 
 void init_keyboard(const cpu_t *cpu) {
     if (!boot_flags.i8042) {
         dprintk("No i8042 microcontroller detected\n");
+        i8042_present = false;
         return;
     }
+    i8042_present = true;
 
     printk("Initializing keyboard driver\n");
 
@@ -182,6 +198,9 @@ unsigned int keyboard_process_keys(void) {
     unsigned n = 0;
     unsigned char key, scan;
 
+    if (!i8042_present)
+        return n;
+
     while (keyboard_state.curr != keyboard_state.init) {
         scan = keyboard_state.buf[keyboard_state.init];
 
@@ -192,6 +211,10 @@ unsigned int keyboard_process_keys(void) {
             if (keyboard_state.shift)
                 vga_scroll_up();
             break;
+        case SCAN_DEL:
+            if (keyboard_state.alt && keyboard_state.ctrl)
+                reboot();
+            break;
         case SCAN_PAGEDOWN:
             if (keyboard_state.shift)
                 vga_scroll_down();
@@ -211,6 +234,11 @@ unsigned int keyboard_process_keys(void) {
 void keyboard_interrupt_handler(void) {
     unsigned char status;
 
+    if (!i8042_present) {
+        apic_EOI();
+        return;
+    }
+
     status = inb(KEYBOARD_PORT_CMD);
     if (status & KEYBOARD_STATUS_OUT_FULL) {
         char scan = inb(KEYBOARD_PORT_DATA);

drivers/serial.c

@@ -221,6 +221,19 @@ int serial_write(io_port_t port, const char *buf, size_t len) {
     return rc;
 }
 
+#define NUM_PLUS 3
+static inline void uart_reboot(char c) {
+    static uint8_t break_cmd = NUM_PLUS;
+
+    if (c != '+') {
+        break_cmd = NUM_PLUS;
+        return;
+    }
+
+    if (--break_cmd == 0)
+        reboot();
+}
+
 void uart_interrupt_handler(void) {
     for (unsigned int i = 0; i < ARRAY_SIZE(com_ports); ++i) {
         com_port_t com_port = com_ports[i];
@@ -238,6 +251,7 @@ void uart_interrupt_handler(void) {
             input_state.curr = (input_state.curr + 1) % sizeof(input_state.buf);
 
             printk("%c", input);
+            uart_reboot(input);
         }
     }
 

include/acpi_ktf.h

@@ -295,6 +295,7 @@ extern void acpi_walk_subtables(ACPI_SUBTABLE_HEADER *entry, uint32_t length,
 
 extern ACPI_STATUS init_acpi(void);
 extern void acpi_power_off(void);
+extern void acpi_reboot(void);
 
 #endif /* KTF_ACPICA */
 #endif /* KTF_ACPI_H */

include/cmdline.h

@@ -68,6 +68,7 @@ extern bool opt_fpu;
 extern bool opt_qemu_console;
 extern bool opt_poweroff;
 extern bool opt_fb_scroll;
+extern unsigned long opt_reboot_timeout;
 
 extern const char *kernel_cmdline;
 

include/drivers/keyboard.h

@@ -33,13 +33,18 @@
 
 #define KEYBOARD_PORT1_IRQ 0x01
 #define KEYBOARD_PORT2_IRQ 0x04 /* Second port */
-#define KEYBOARD_PORT1_IRQ_OFFSET                                                        \
-    (PIC_IRQ0_OFFSET + KEYBOARD_PORT1_IRQ) /* keyboard first channel irq offset */
+/* keyboard first channel irq offset */
+#define KEYBOARD_PORT1_IRQ_OFFSET (PIC_IRQ0_OFFSET + KEYBOARD_PORT1_IRQ)
 #define KEYBOARD_PORT1_IRQ_VECTOR KEYBOARD_PORT1_IRQ_OFFSET
 #define KEYBOARD_PORT2_IRQ_OFFSET (PIC_IRQ0_OFFSET + KEYBOARD_PORT2_IRQ)
 #define KEYBOARD_PORT2_IRQ_VECTOR KEYBOARD_PORT2_IRQ_OFFSET
 
-#define KEYBOARD_STATUS_OUT_FULL 0x01 /* bit set when the keyboard buffer is full */
+/* bit set when the keyboard output buffer is full */
+#define KEYBOARD_STATUS_OUT_FULL 0x01
+/* bit set when the keyboard input buffer is full */
+#define KEYBOARD_STATUS_IN_FULL 0x02
+
+#define KEYBOARD_RESET_CMD 0xFE
 
 typedef enum {
     KEYBOARD_CMD_WRITE_CONFIGURATION = 0x60, /* Write configuration byte */
@@ -117,6 +122,7 @@ typedef enum scan_code scan_code_t;
 
 /* External Declarations */
 
+extern void keyboard_reboot(void);
 extern void init_keyboard(const cpu_t *cpu);
 extern void keyboard_interrupt_handler(void);
 extern unsigned int keyboard_process_keys(void);

include/ktf.h

@@ -40,6 +40,7 @@ typedef uint16_t io_port_t;
 
 extern bool opt_debug;
 
+extern void reboot(void);
 extern void kernel_main(void) __noreturn;
 extern unsigned long test_main(void *unused);
 

include/lib.h

@@ -167,6 +167,10 @@ static inline void hlt(void) {
     asm volatile("hlt");
 }
 
+static inline void int3(void) {
+    asm volatile("int3");
+}
+
 static inline unsigned long read_flags(void) {
     unsigned long flags;
 
@@ -469,6 +473,7 @@ static inline void enable_fpu(void) {
 /* External declarations */
 
 extern void halt(void);
+extern void hard_reboot(void);
 
 extern void srand(unsigned s);
 

lib/lib.c

@@ -36,6 +36,17 @@ void __noreturn halt(void) {
     }
 }
 
+/* Trigger Triple Fault */
+void __noreturn hard_reboot(void) {
+    idt_ptr_t idt_ptr = {0};
+
+    cli();
+    lidt(&idt_ptr);
+    int3();
+
+    halt();
+}
+
 static uint64_t seed;
 
 void srand(unsigned s) {