From a1c44dca93a58b8e7fe6457b3f3f5c02b27c816a Mon Sep 17 00:00:00 2001
From: Ali Mashtizadeh <mashti@cs.stanford.edu>
Date: Thu, 10 Jul 2014 14:01:15 -0700
Subject: [PATCH] IRQ registration helper functions

---
 sys/SConscript      |  1 +
 sys/amd64/ioapic.c  |  2 +-
 sys/amd64/irq.c     | 52 +++++++++++++++++++++++++++++++++++++++++++++
 sys/amd64/lapic.c   |  2 +-
 sys/amd64/machine.c |  1 +
 sys/amd64/trap.c    | 36 +++++++++++++++++++++++--------
 sys/amd64/trap.h    |  1 +
 sys/include/irq.h   | 20 +++++++++++++++++
 8 files changed, 104 insertions(+), 11 deletions(-)
 create mode 100644 sys/amd64/irq.c
 create mode 100644 sys/include/irq.h

diff --git a/sys/SConscript b/sys/SConscript
index 9caaea5..49c5ae4 100644
--- a/sys/SConscript
+++ b/sys/SConscript
@@ -18,6 +18,7 @@ src_amd64 = [
     "amd64/pmap.c",
     "amd64/lapic.c",
     "amd64/ioapic.c",
+    "amd64/irq.c",
     "dev/x86/debugcons.c",
     "dev/x86/vgacons.c",
     "dev/x86/ide.c",
diff --git a/sys/amd64/ioapic.c b/sys/amd64/ioapic.c
index 3e6960c..fc0a264 100644
--- a/sys/amd64/ioapic.c
+++ b/sys/amd64/ioapic.c
@@ -51,7 +51,7 @@ IOAPIC_Init()
     uint32_t id = (IOAPIC_Read(IOAPICID) >> 24) & 0x0F;
     uint32_t maxInts = (IOAPIC_Read(IOAPICVER) >> 16) & 0xFF;
 
-    kprintf("IOAPIC ID:%d Max Interrupts: %d\n", id, maxInts);
+    kprintf("IOAPIC: ID:%d Max Interrupts: %d\n", id, maxInts);
 
     for (i = 0; i <= IOREDTBL_LEN; i++)
     {
diff --git a/sys/amd64/irq.c b/sys/amd64/irq.c
new file mode 100644
index 0000000..7d0f89e
--- /dev/null
+++ b/sys/amd64/irq.c
@@ -0,0 +1,52 @@
+
+#include <stdint.h>
+
+#include <kassert.h>
+
+#include "trap.h"
+#include "ioapic.h"
+#include <irq.h>
+
+LIST_HEAD(IRQHandlerList, IRQHandler);
+struct IRQHandlerList handlers[T_IRQ_LEN];
+
+void
+IRQ_Init()
+{
+    int i;
+
+    for (i = 0; i < T_IRQ_LEN; i++)
+    {
+	LIST_INIT(&handlers[i]);
+    }
+}
+
+void
+IRQ_Handler(int irq)
+{
+    struct IRQHandler *h;
+    LIST_FOREACH(h, &handlers[irq], link)
+    {
+	h->cb(h->arg);
+    }
+}
+
+void
+IRQ_Register(int irq, struct IRQHandler *h)
+{
+    ASSERT(irq < T_IRQ_LEN);
+
+    LIST_INSERT_HEAD(&handlers[irq], h, link);
+
+    IOAPIC_Enable(irq);
+}
+
+void
+IRQ_Unregister(int irq, struct IRQHandler *h)
+{
+    LIST_REMOVE(h, link);
+
+    if (LIST_EMPTY(&handlers[irq]))
+	IOAPIC_Disable(irq);
+}
+
diff --git a/sys/amd64/lapic.c b/sys/amd64/lapic.c
index 4e83d69..9872391 100644
--- a/sys/amd64/lapic.c
+++ b/sys/amd64/lapic.c
@@ -99,7 +99,7 @@ LAPIC_Init()
     base = rdmsr(IA32_APIC_BASE_MSR);
     wrmsr(IA32_APIC_BASE_MSR, base | IA32_APIC_BASE_MSR_ENABLE);
 
-    kprintf("CPU %d LAPIC found at 0x%016llx\n", LAPIC_CPU(), base);
+    kprintf("LAPIC: CPU %d found at 0x%016llx\n", LAPIC_CPU(), base);
 
     // Enable interrupts
     LAPIC_Write(LAPIC_SIV, LAPIC_SIV_ENABLE | T_IRQ_SPURIOUS);
diff --git a/sys/amd64/machine.c b/sys/amd64/machine.c
index 24f0286..4948c2c 100644
--- a/sys/amd64/machine.c
+++ b/sys/amd64/machine.c
@@ -89,6 +89,7 @@ void Machine_Init()
     PAlloc_AddRegion(16*1024*1024, 16*1024*1024);
     PMap_Init();
 
+    IRQ_Init();
     LAPIC_Init();
     IOAPIC_Init();
 
diff --git a/sys/amd64/trap.c b/sys/amd64/trap.c
index 5d0d5dd..daa54bc 100644
--- a/sys/amd64/trap.c
+++ b/sys/amd64/trap.c
@@ -3,6 +3,7 @@
 
 #include <kconfig.h>
 #include <kassert.h>
+#include <irq.h>
 
 #include "amd64.h"
 #include "lapic.h"
@@ -89,10 +90,10 @@ trap_entry(TrapFrame *tf)
     // Halt on kernel errors
     if (tf->vector <= T_CPU_LAST && tf->cs == SEL_KCS)
     {
-        Trap_Dump(tf);
-
-        while (1)
-            hlt();
+	kprintf("Kernel Fault!\n");
+	Trap_Dump(tf);
+	while (1)
+	    hlt();
     }
 
     switch (tf->vector)
@@ -111,15 +112,32 @@ trap_entry(TrapFrame *tf)
 
     if (tf->vector >= T_IRQ_BASE && tf->vector <= T_IRQ_MAX)
     {
-        kprintf("IRQ: %d\n", tf->vector);
-
-        LAPIC_SendEOI();
+	kprintf("IRQ: %d\n", tf->vector);
+	IRQ_Handler(tf->vector - T_IRQ_BASE);
+	LAPIC_SendEOI();
 
         return;
     }
 
-    Trap_Dump(tf);
+    // LAPIC Special Vectors
+    if (tf->vector == T_IRQ_SPURIOUS)
+	return;
+    if (tf->vector == T_IRQ_ERROR)
+    {
+	kprintf("LAPIC Error!\n");
+	while (1)
+	    hlt();
+    }
+    if (tf->vector == T_IRQ_THERMAL)
+    {
+	kprintf("Thermal Error!\n");
+	while (1)
+	    hlt();
+    }
 
-    while (1) { }
+    kprintf("Unhandled Interrupt!\n");
+    Trap_Dump(tf);
+    while (1)
+	hlt();
 }
 
diff --git a/sys/amd64/trap.h b/sys/amd64/trap.h
index 0ccfe28..282f3e9 100644
--- a/sys/amd64/trap.h
+++ b/sys/amd64/trap.h
@@ -31,6 +31,7 @@
 #define T_IRQ_TIMER     (T_IRQ_BASE + 0)
 #define T_IRQ_KBD       (T_IRQ_BASE + 1)
 #define T_IRQ_COM1      (T_IRQ_BASE + 4)
+#define T_IRQ_MOUSE     (T_IRQ_BASE + 12)
 #define T_IRQ_SPURIOUS  (T_IRQ_BASE + 24)
 #define T_IRQ_ERROR     (T_IRQ_BASE + 25)
 #define T_IRQ_THERMAL   (T_IRQ_BASE + 26)
diff --git a/sys/include/irq.h b/sys/include/irq.h
new file mode 100644
index 0000000..d94cfcf
--- /dev/null
+++ b/sys/include/irq.h
@@ -0,0 +1,20 @@
+
+#ifndef __IRQ_H__
+#define __IRQ_H__
+
+#include <queue.h>
+
+typedef struct IRQHandler {
+    int irq;
+    void (*cb)(void*);
+    void *arg;
+    LIST_ENTRY(IRQHandler) link;
+} IRQHandler;
+
+void IRQ_Init();
+void IRQ_Handler(int irq);
+void IRQ_Register(int irq, struct IRQHandler *h);
+void IRQ_Unregister(int irq, struct IRQHandler *h);
+
+#endif /* __IRQ_H__ */
+