From 2081b1521963e0d521b3c467d467a2a18940baba Mon Sep 17 00:00:00 2001
From: "Chloe M." <chloe@mensia.org>
Date: Mon, 13 Jul 2026 03:54:22 +0000
Subject: [PATCH] ptos/amd64+hal: intr: Add IRQL managmenet

Signed-off-by: Chloe M. <chloe@mensia.org>
---
 service/ptos/arch/amd64/cpu/intr.c | 57 ++++++++++++++++++++++++++++++
 service/ptos/head/hal/intr.h       | 23 ++++++++++++
 service/ptos/head/ke/bugcheck.h    |  6 +++-
 service/ptos/ke/bugcheck.c         |  4 ++-
 4 files changed, 88 insertions(+), 2 deletions(-)

diff --git a/service/ptos/arch/amd64/cpu/intr.c b/service/ptos/arch/amd64/cpu/intr.c
index c76ab45..1589017 100644
--- a/service/ptos/arch/amd64/cpu/intr.c
+++ b/service/ptos/arch/amd64/cpu/intr.c
@@ -7,6 +7,7 @@
  */
 
 #include <hal/intr.h>
+#include <ke/bugcheck.h>
 #include <machine/intr.h>
 #include <machine/idt.h>
 #include <ptdef.h>
@@ -14,6 +15,20 @@
 /* Globals */
 static INTR_HANDLER HandlerTable[256];
 
+/*
+ * Set a new IRQL
+ */
+static inline VOID
+SetIrql(IRQL Irql)
+{
+    ASMV(
+        "mov %0, %%cr8"
+        :
+        : "r" ((UQUAD)Irql)
+        : "memory"
+    );
+}
+
 UCHAR
 HalIntrRegister(INTR_HANDLER *Handler, BOOLEAN IsUser)
 {
@@ -56,3 +71,45 @@ HalIntrRegister(INTR_HANDLER *Handler, BOOLEAN IsUser)
     /* No more vectors */
     return 0;
 }
+
+IRQL
+HalGetIrql(VOID)
+{
+    UQUAD CurrentIrql;
+
+    ASMV(
+        "mov %%cr8, %0"
+        : "=r" (CurrentIrql)
+        :
+        : "memory"
+    );
+
+    return (IRQL)CurrentIrql;
+}
+
+IRQL
+HalRaiseIrql(IRQL Irql)
+{
+    IRQL CurrentIrql;
+
+    CurrentIrql = HalGetIrql();
+    if (Irql < CurrentIrql) {
+        KeBugCheck(BUGCHECK_IRQL_NOT_GTE, "got bad irql\n");
+    }
+
+    SetIrql(Irql);
+    return CurrentIrql;
+}
+
+IRQL
+HalLowerIrql(IRQL Irql)
+{
+    IRQL CurrentIrql;
+
+    CurrentIrql = HalGetIrql();
+    if (Irql > CurrentIrql) {
+        KeBugCheck(BUGCHECK_IRQL_NOT_LTE, "got bad irql\n");
+    }
+
+    return CurrentIrql;
+}
diff --git a/service/ptos/head/hal/intr.h b/service/ptos/head/hal/intr.h
index 6548cba..a5dbd07 100644
--- a/service/ptos/head/hal/intr.h
+++ b/service/ptos/head/hal/intr.h
@@ -52,4 +52,27 @@ typedef struct _INTR_HANDLER {
  */
 UCHAR HalIntrRegister(INTR_HANDLER *Handler, BOOLEAN IsUser);
 
+/*
+ * Returns the current IRQL
+ */
+IRQL HalGetIrql(VOID);
+
+/*
+ * Raise the IRQL level to a higher level
+ *
+ * @Irql: IRQL to raise to
+ *
+ * Returns the previous IRQL
+ */
+IRQL HalRaiseIrql(IRQL Irql);
+
+/*
+ * Lower the IRQL level to a lower level
+ *
+ * @Irql: IRQL to lower to
+ *
+ * Returns the previous IRQL
+ */
+IRQL HalLowerIrql(IRQL Irql);
+
 #endif  /* !_HAL_INTR_H_ */
diff --git a/service/ptos/head/ke/bugcheck.h b/service/ptos/head/ke/bugcheck.h
index 7cad9ff..82dd702 100644
--- a/service/ptos/head/ke/bugcheck.h
+++ b/service/ptos/head/ke/bugcheck.h
@@ -19,13 +19,17 @@
  * @BUGCHECK_IO_ERROR:      Fatal I/O error
  * @BUGCHECK_UNBOUND_RESRC: Fatal unbound resource
  * @BUGCHECK_EXCEPTION:     Fatal exception
+ * @BUGCHECK_IRQL_NOT_GTE:  IRQL not greater than or equal
+ * @BUGCHECK_IRQL_NOT_LTE:  IRQL not less than or equal
  */
 typedef enum {
     BUGCHECK_MISC,
     BUGCHECK_OOM,
     BUGCHECK_IO_ERROR,
     BUGCHECK_UNBOUND_RESRC,
-    BUGCHECK_EXCEPTION
+    BUGCHECK_EXCEPTION,
+    BUGCHECK_IRQL_NOT_GTE,
+    BUGCHECK_IRQL_NOT_LTE
 } BUGCHECK_REASON;
 
 /*
diff --git a/service/ptos/ke/bugcheck.c b/service/ptos/ke/bugcheck.c
index e3db2d2..8d33b42 100644
--- a/service/ptos/ke/bugcheck.c
+++ b/service/ptos/ke/bugcheck.c
@@ -36,7 +36,9 @@ static CHAR *ReasonTable[] = {
     [BUGCHECK_OOM]  = "out of memory",
     [BUGCHECK_IO_ERROR] = "i/o error",
     [BUGCHECK_UNBOUND_RESRC] = "unbounded resource",
-    [BUGCHECK_EXCEPTION] = "fatal exception"
+    [BUGCHECK_EXCEPTION] = "fatal exception",
+    [BUGCHECK_IRQL_NOT_GTE] = "irql not greater than or equal",
+    [BUGCHECK_IRQL_NOT_LTE] = "irql not less than or equal"
 };
 
 VOID