Wrap IRQ with ASM

Makefile

@@ -17,7 +17,7 @@ CPPFLAGS += $(foreach dir, $(SUBDIRS), -I$(dir))
 asmsrc=$(wildcard arch/$(ARCH)/boot/*.asm)
 asmobj=$(asmsrc:%.asm=%.o)
 csrc=$(shell find $(SUBDIRS) -type f -name "*.c")#   $(wildcard *.c)
-cobj=$(csrc:%.c=%.o) arch/$(ARCH)/cpu_context_switch.o arch/$(ARCH)/irq_pit.o
+cobj=$(csrc:%.c=%.o) arch/$(ARCH)/cpu_context_switch.o arch/$(ARCH)/irq_pit.o arch/$(ARCH)/irq_wrappers.o
 deps = $(csrc:%.c=%.d)
 
 kernel kernel.sym &: $(asmobj) $(cobj) linker.ld
@@ -37,8 +37,6 @@ disk.img:
 #https://gcc.gnu.org/onlinedocs/gcc/x86-Function-Attributes.html#x86-Function-Attributes
 arch/$(ARCH)/exception_handler.o:arch/$(ARCH)/exception_handler.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) -mgeneral-regs-only  -c $< -o $@
-arch/$(ARCH)/irq_handler.o:arch/$(ARCH)/irq_handler.c
-	$(CC) $(CFLAGS) $(CPPFLAGS) -mgeneral-regs-only  -c $< -o $@
 
 %.o:%.asm
 	$(AS) $(ASFLAGS) -o $@ $<

README.md

@@ -21,7 +21,7 @@ To generate iso image
 
  you can also test it
 
- `make self_test`
+ `make test`
 
 # Debug
 

arch/x86/interrupt.h

@@ -52,6 +52,3 @@ DECLARE_INTERRUPT(EXCEPTION_RESERVED_11)
 
 // IRQ
 void pit_handler(struct interrupt_frame *frame);
-void keyboard_handler(struct interrupt_frame *frame);
-void timer_handler(struct interrupt_frame *frame);
-void serial_handler(struct interrupt_frame *frame);

arch/x86/irq.c

@@ -1,7 +1,10 @@
 #include "irq.h"
 #include "idt.h"
+#include "io.h"
+#include "klibc.h"
 #include "pic.h"
 #include "stdarg.h"
+#include "types.h"
 
 int irqSetup()
 {
@@ -9,10 +12,28 @@ int irqSetup()
     return 0;
 }
 
+// Assembly defined array. This is used to wrap C function than cannot:
+// * get some cpu state
+// * return using "iret" instead of "ret" without some compiler __attribute__
+extern vaddr_t irq_handler_wrapper_array[IRQ_NUM];
+
 irq_handler irq_handler_array[IRQ_NUM] = {
     NULL,
 };
 
+void interrupt_handler_pic(int interrupt, struct interrupt_frame *frame)
+{
+    if (0 > interrupt || IRQ_NUM <= interrupt) {
+        pr_err("Trying to handle unknow interrupt %d\n", interrupt);
+        return;
+    }
+
+    EOIIrq(interrupt);
+
+    if (irq_handler_array[interrupt] != NULL)
+        irq_handler_array[interrupt](frame);
+}
+
 int irqSetRoutine(int irq, irq_handler handler)
 {
     uint32_t flags;
@@ -32,3 +53,23 @@ int irqSetRoutine(int irq, irq_handler handler)
     restore_IRQs(flags);
     return 0;
 }
+
+int irqSetRoutineWrapped(int irq, irq_handler handler)
+{
+    uint32_t flags;
+    if ((irq < 0) || irq >= IRQ_NUM)
+        return -1;
+
+    disable_IRQs(flags);
+
+    irq_handler_array[irq] = handler;
+
+    if (handler != NULL) {
+        int ret = idt_set_handler(IRQ_INTERRUPT_BASE_ADDRESS + irq,
+                                  (unsigned int)irq_handler_wrapper_array[irq], 0);
+        if (!ret)
+            enableIrq(irq);
+    }
+    restore_IRQs(flags);
+    return 0;
+}

arch/x86/irq.h

@@ -37,4 +37,7 @@
 // __attribute__((interrupt)) void (*irq_handler)(int irq);
 typedef void (*irq_handler)(struct interrupt_frame *frame);
 int irqSetup();
+// For C coded handler (The interrupt specific part is managed by a wrapper)
+int irqSetRoutineWrapped(int irq, irq_handler handler);
+// For ASM handler taking care of the special instruction needed by an IRQ handler
 int irqSetRoutine(int irq, irq_handler handler);

arch/x86/irq_handler.c

@@ -1,29 +0,0 @@
-#include "interrupt.h"
-#include "io.h"
-#include "irq.h"
-#include "keyboard.h"
-#include "pic.h"
-#include "serial.h"
-#include "vga.h"
-
-// Need GCC > 6
-__attribute__((interrupt)) void keyboard_handler(struct interrupt_frame *frame)
-{
-    EOIIrq(IRQ_KEYBOARD);
-    keyboard_do_irq();
-    (void)frame;
-}
-
-__attribute__((interrupt)) void timer_handler(struct interrupt_frame *frame)
-{
-    static int timeCnt = 0;
-    EOIIrq(IRQ_TIMER);
-    VGAPrintf(RED, BLACK, 20, VGA_HEIGHT - 1, "IRQ %d", timeCnt++);
-    (void)frame;
-}
-
-__attribute__((interrupt)) void serial_handler(struct interrupt_frame *frame)
-{
-    EOIIrq(IRQ_COM1);
-    serialDoIrq(frame);
-}

core/klibc.h

@@ -1,4 +1,5 @@
 #pragma once
+#include "assert.h"
 #include "stdarg.h"
 #include "minmax.h"
 

core/main.c

@@ -7,6 +7,7 @@
 #include "interrupt.h"
 #include "io.h"
 #include "irq.h"
+#include "keyboard.h"
 #include "klibc.h"
 #include "kthread.h"
 #include "mem.h"
@@ -134,7 +135,7 @@ void kmain(unsigned long magic, unsigned long addr)
     }
 
     printf("Setting up IRQ handlers\n");
-    irqSetRoutine(IRQ_KEYBOARD, keyboard_handler);
+    irqSetRoutineWrapped(IRQ_KEYBOARD, keyboard_do_irq);
 
     printf("Enabling HW interrupts\n");
     // Enabling the HW interrupts

drivers/serial.c

@@ -32,7 +32,7 @@ void serialSetup(int speed)
              UART_1_STOP_BIT); // 8 bits, no parity, one stop bit
     outb(PORT + 2, 0xC7);      // Enable FIFO, clear them, with 14-byte threshold
     outb(PORT + 4, 0x0B);      // IRQs enabled, RTS/DSR set
-    irqSetRoutine(IRQ_COM1, serial_handler);
+    irqSetRoutineWrapped(IRQ_COM1, serialDoIrq);
 }
 
 int isTransmitEmpty()