x86_64: register local APIC NMI structures

src/platform/x86_64/apic/apic.c

@@ -133,6 +133,26 @@ int apicInit() {
 
             overrideIRQRegister(irqor);
             break;
+        case MADT_TYPE_LOCAL_NMI:
+            ACPIMADTLocalNMI *lnmiEntry = (ACPIMADTLocalNMI *) ptr;
+            KDEBUG("local APIC NMI on ACPI ID 0x%02X LINT#%d with flags 0x%04X (%s, %s)\n",
+                lnmiEntry->procID, lnmiEntry->lint & 1, lnmiEntry->flags,
+                lnmiEntry->flags & MADT_INTERRUPT_LEVEL ? "level" : "edge",
+                lnmiEntry->flags & MADT_INTERRUPT_LOW ? "low" : "high");
+
+            LocalNMI *lnmi = calloc(1, sizeof(LocalNMI));
+            if(!lnmi) {
+                KERROR("could not allocate memory for local APIC NMI\n");
+                while(1);
+            }
+
+            lnmi->procID = lnmiEntry->procID;
+            lnmi->lint = lnmiEntry->lint;
+            if(override->flags & MADT_INTERRUPT_LEVEL) lnmi->level = 1;
+            if(override->flags & MADT_INTERRUPT_LOW) lnmi->low = 0;
+
+            lnmiRegister(lnmi);
+            break;
         default:
             KWARN("unimplemented MADT entry type 0x%02X with length %d, skipping...\n", ptr[0], ptr[1]);
         }

src/platform/x86_64/apic/nmi.c

@@ -0,0 +1,49 @@
+/*
+ * lux - a lightweight unix-like operating system
+ * Omar Elghoul, 2024
+ * 
+ * Platform-Specific Code for x86_64
+ */
+
+/* Non-Maskable Interrupt Implementation */
+
+/* Intel Software Developer's Manual Volume 3A Part 1 Chapter 11.5.1:
+ *
+ * The trigger mode of local APIC NMIs is always set to be edge-sensitive, and
+ * that of local APIC ExtINTs is always set to level-sensitive. LINT1 is always
+ * hardwired to level-sensitive, and only LINT0 can be configured to use either
+ * edge or level according to the information from the ACPI MADT.
+ */
+
+#include <platform/apic.h>
+#include <platform/smp.h>
+#include <kernel/logger.h>
+
+static LocalNMI *lnmis = NULL;
+static BusNMI *bnmis = NULL;
+static int nlnmi = 0, nbnmi = 0;
+
+/* lnmiRegister(): registers a local APIC NMI
+ * params: lnmi - local APIC NMI structure
+ * returns: count of local APIC NMIs
+ */
+
+int lnmiRegister(LocalNMI *lnmi) {
+    if(!lnmis) lnmis = lnmi;
+    else {
+        LocalNMI *list = lnmis;
+        while(list->next) list = list->next;
+        list->next = lnmi;
+    }
+
+    return nlnmi++;
+}
+
+/* lnmiCount(): returns the number of local APIC NMIs
+ * params: none
+ * returns: number of local APIC NMIs
+ */
+
+int lnmiCount() {
+    return nlnmi;
+}

src/platform/x86_64/include/platform/apic.h

@@ -189,14 +189,14 @@ typedef struct IRQOverride {
 
 typedef struct BusNMI {
     uint8_t source;
-    uint16_t flags;
+    int level, low;
     uint32_t gsi;
     struct BusNMI *next;
 } BusNMI;
 
 typedef struct LocalNMI {
     uint8_t procID;
-    uint16_t flags;
+    int level, low;
     uint8_t lint;
     struct LocalNMI *next;
 } LocalNMI;
@@ -217,6 +217,9 @@ void ioapicWrite(IOAPIC *, uint32_t, uint32_t);
 uint32_t ioapicRead(IOAPIC *, uint32_t);
 int ioapicMask(int, int);
 
+int lnmiRegister(LocalNMI *);
+int lnmiCount();
+
 int overrideIRQRegister(IRQOverride *);
 int overrideIRQCount();
 IRQOverride *findOverrideIRQ(uint64_t);