[feat] 100Hz task switch

kernel/main.cpp

@@ -8,11 +8,14 @@
 #include <memory/heap.h>
 #include <scheduler.h>
 #include <fs.h>
+#include <gdt.h>
+#include <idt.h>
+#include <pic.h>
+#include <pit.h>
 
 extern EFI_SYSTEM_TABLE *ST;
 
 inline void init_gop() {
-    // 初始化 GOP
     EFI_GUID gop_guid = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
     EFI_GRAPHICS_OUTPUT_PROTOCOL *GOP;
     uefi_call_wrapper(ST->BootServices->SetWatchdogTimer, 4, 0, 0, 0, NULL);
@@ -21,7 +24,6 @@ inline void init_gop() {
 }
 
 inline void init_serial() {
-    // 初始化串行驱动
     EFI_SERIAL_IO_PROTOCOL *SerialIo = NULL;
     EFI_GUID gEfiSerialIoProtocolGuid = EFI_SERIAL_IO_PROTOCOL_GUID;
     EFI_HANDLE *SerialHandles = NULL;
@@ -45,6 +47,26 @@ inline void init_serial() {
     }
 }
 
+// External: PIT IRQ handler defined in pit.cpp
+extern "C" void pit_irq_handler(void);
+
+// PIC IRQ handler — dispatches IRQ 0 (timer)
+static void irq_handler(trap_frame* frame) {
+    UINT8 vector = (UINT8)frame->vector;
+    UINT8 irq = vector - PIC_IRQ_BASE;
+
+    switch (irq) {
+        case 0:  // PIT timer
+            pit_irq_handler();
+            break;
+        default:
+            break;
+    }
+
+    // Send EOI to PIC
+    pic_send_eoi(irq);
+}
+
 extern "C" void kernel_main() {
     init_gop();
     init_serial();
@@ -53,7 +75,7 @@ extern "C" void kernel_main() {
     uefi_call_wrapper(ST->ConOut->OutputString, 2, ST->ConOut, (CHAR16*)L"Kernel is running!\n");
 
     uefi_call_wrapper(ST->ConOut->ClearScreen, 1, ST->ConOut);
-    serial_write("\n\n"); // 防止和前面串了serial.log看不清
+    serial_write("\n\n");
 
     // init memory managers
     serial_write("Sylva: init PMM...\n");
@@ -108,27 +130,46 @@ extern "C" void kernel_main() {
     pf_print("Welcome to Sylva OS!\n");
     serial_write(" Kernel prepared well.\n");
 
+    // --- Interrupt infrastructure ---
+    serial_write("Sylva: init GDT...\n");
+    gdt_init();
+
+    serial_write("Sylva: init IDT...\n");
+    idt_init();
+
+    serial_write("Sylva: init PIC...\n");
+    pic_init();
+
+    // Register IRQ handler (vector 0x20 = PIC_IRQ_BASE + 0)
+    idt_set_handler(PIC_IRQ_BASE + 0, irq_handler);
+
+    serial_write("Sylva: init PIT...\n");
+    pit_init();
+    pit_set_tick_handler(scheduler_tick);
+
+    // Enable interrupts
+    ASM("sti");
+    serial_write("Sylva: interrupts enabled\n");
+
     // --- Multitasking demo ---
     serial_write("Sylva: creating tasks...\n");
 
-    // Task A: prints a message 3 times, yielding between each
+    // Task A: prints messages — preemption handles time slicing
     task_create("taskA", []() {
         for (int i = 0; i < 3; i++) {
             serial_write("[taskA] running iteration ");
             serial_write_hex(i);
             serial_write("\n");
-            yield();
         }
         serial_write("[taskA] done\n");
     });
 
-    // Task B: prints a message 5 times
+    // Task B: prints messages
     task_create("taskB", []() {
         for (int i = 0; i < 5; i++) {
             serial_write("[taskB] hello from taskB #");
             serial_write_hex(i);
             serial_write("\n");
-            yield();
         }
         serial_write("[taskB] done\n");
     });
@@ -136,10 +177,9 @@ extern "C" void kernel_main() {
     // Task C: short task
     task_create("taskC", []() {
         serial_write("[taskC] quick task\n");
-        yield();
         serial_write("[taskC] finished\n");
     });
 
-    serial_write("Sylva: starting scheduler\n");
+    serial_write("Sylva: starting preemptive scheduler\n");
     scheduler_run();  // never returns
-}
+}