From 3987e7bca6447d87d6c89b1d36c40f9101b54802 Mon Sep 17 00:00:00 2001
From: Matheus <matheusuky@gmail.com>
Date: Thu, 4 May 2023 13:52:35 -0300
Subject: [PATCH] interrupt: split setipl into raiseipl and loweripl

---
 kernel-src/include/kernel/interrupt.h | 10 ++++++----
 kernel-src/sys/interrupt.c            | 18 ++++++++++++++----
 kernel-src/sys/timer.c                |  8 ++++----
 3 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/kernel-src/include/kernel/interrupt.h b/kernel-src/include/kernel/interrupt.h
index 7eac1dbb..b524eea7 100644
--- a/kernel-src/include/kernel/interrupt.h
+++ b/kernel-src/include/kernel/interrupt.h
@@ -11,10 +11,11 @@
 	#error Unsupported architecture!
 #endif
 
-#define IPL_MAX  -1
-#define IPL_NONE 0
+#define IPL_EXCEPT  -1
+#define IPL_MAX 0
 #define IPL_TIMER 1
-#define IPL_BASE 1000
+#define IPL_KEYBOARD 2
+#define IPL_NORMAL 1000
 
 struct _isr_t;
 typedef struct _isr_t {
@@ -27,7 +28,8 @@ typedef struct _isr_t {
 
 void interrupt_register(int vector, void (*func)(isr_t *self, context_t *ctx), void (*eoi)(isr_t *self), long priority);
 isr_t *interrupt_allocate(void (*func)(isr_t *self, context_t *ctx), void (*eoi)(isr_t *self), long priority);
-long interrupt_setipl(long newipl);
+long interrupt_loweripl(long newipl);
+long interrupt_raiseipl(long ipl);
 bool interrupt_set(bool status);
 
 #endif
diff --git a/kernel-src/sys/interrupt.c b/kernel-src/sys/interrupt.c
index f6f8dc4c..fe003eb5 100644
--- a/kernel-src/sys/interrupt.c
+++ b/kernel-src/sys/interrupt.c
@@ -12,12 +12,12 @@ void interrupt_isr(int vec, context_t *ctx) {
 		_panic("Unregistered interrupt", ctx);
 
 	if (_cpu()->ipl > isr->priority) {
-		long oldipl = interrupt_setipl(isr->priority);
+		long oldipl = interrupt_raiseipl(isr->priority);
 
 		isr->func(isr, ctx);
 		interrupt_set(false);
 
-		interrupt_setipl(oldipl);
+		interrupt_loweripl(oldipl);
 	} else {
 		isr->pending = true;
 	}
@@ -51,10 +51,11 @@ isr_t *interrupt_allocate(void (*func)(isr_t *self, context_t *ctx), void (*eoi)
 	return isr;
 }
 
-long interrupt_setipl(long ipl) {
+long interrupt_loweripl(long ipl) {
 	bool oldintstatus = interrupt_set(false);
 	long oldipl = _cpu()->ipl;
-	_cpu()->ipl = ipl;
+	if (oldipl > ipl)
+		_cpu()->ipl = ipl;
 	interrupt_set(oldintstatus);
 
 	// TODO do pending interrupts
@@ -62,6 +63,15 @@ long interrupt_setipl(long ipl) {
 	return oldipl;
 }
 
+long interrupt_raiseipl(long ipl) {
+	bool oldintstatus = interrupt_set(false);
+	long oldipl = _cpu()->ipl;
+	if (oldipl < ipl)
+		_cpu()->ipl = ipl;
+	interrupt_set(oldintstatus);
+	return oldipl;
+}
+
 void arch_interrupt_disable();
 void arch_interrupt_enable();
 
diff --git a/kernel-src/sys/timer.c b/kernel-src/sys/timer.c
index 410bc2e1..231dabec 100644
--- a/kernel-src/sys/timer.c
+++ b/kernel-src/sys/timer.c
@@ -69,18 +69,18 @@ void timer_resume(timer_t *timer) {
 }
 
 void timer_stop(timer_t *timer) {
-	long oldipl = interrupt_setipl(IPL_TIMER);
+	long oldipl = interrupt_raiseipl(IPL_TIMER);
 	spinlock_acquire(&timer->lock);
 
 	timer->tickcurrent += timer->stop(timer);
 	timer->running = false;
 
 	spinlock_release(&timer->lock);
-	interrupt_setipl(oldipl);
+	interrupt_loweripl(oldipl);
 }
 
 void timer_insert(timer_t *timer, timerentry_t* entry, time_t us) {
-	long oldipl = interrupt_setipl(IPL_TIMER);
+	long oldipl = interrupt_raiseipl(IPL_TIMER);
 	spinlock_acquire(&timer->lock);
 
 	if (timer->running)
@@ -95,7 +95,7 @@ void timer_insert(timer_t *timer, timerentry_t* entry, time_t us) {
 	}
 
 	spinlock_release(&timer->lock);
-	interrupt_setipl(oldipl);
+	interrupt_loweripl(oldipl);
 }
 
 timer_t *timer_new(time_t ticksperus, void (*arm)(time_t), time_t (*stop)()) {