diff --git a/thermosphere/src/barrier.c b/thermosphere/src/barrier.c
new file mode 100644
index 000000000..36cead568
--- /dev/null
+++ b/thermosphere/src/barrier.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdatomic.h>
+#include "barrier.h"
+#include "core_ctx.h"
+#include "utils.h"
+
+
+void barrierInit(Barrier *barrier, u32 coreList)
+{
+    atomic_store(&barrier->val, coreList);
+}
+
+void barrierInitAllButSelf(Barrier *barrier)
+{
+    barrierInit(barrier, getActiveCoreMask() & ~(BIT(currentCoreCtx->coreId)));
+}
+
+void barrierInitAll(Barrier *barrier)
+{
+    barrierInit(barrier, getActiveCoreMask());
+}
+
+void barrierWait(Barrier *barrier)
+{
+    while (atomic_fetch_and(&barrier->val, ~(BIT(currentCoreCtx->coreId))) != 0);
+}
diff --git a/thermosphere/src/barrier.h b/thermosphere/src/barrier.h
new file mode 100644
index 000000000..cf818f8a3
--- /dev/null
+++ b/thermosphere/src/barrier.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <stdatomic.h>
+#include "types.h"
+
+typedef struct Barrier {
+    atomic_uint val;
+} Barrier;
+
+void barrierInit(Barrier *barrier, u32 coreList);
+void barrierInitAllButSelf(Barrier *barrier);
+void barrierInitAll(Barrier *barrier);
+
+void barrierWait(Barrier *barrier);
\ No newline at end of file
diff --git a/thermosphere/src/core_ctx.c b/thermosphere/src/core_ctx.c
index 60f2bcb67..c4d417a13 100644
--- a/thermosphere/src/core_ctx.c
+++ b/thermosphere/src/core_ctx.c
@@ -15,12 +15,15 @@
  */
 
 #include "core_ctx.h"
+#include "utils.h"
 
 // start.s
 extern uintptr_t g_initialKernelEntrypoint;
 
 extern u8 __stacks_top__[], __crash_stacks_top__[];
 
+static atomic_uint g_activeCoreMask = 0;
+
 // Prevents it from being put in BSS
 CoreCtx g_coreCtxs[4] = {
     { .coreId = 0 },
@@ -40,3 +43,13 @@ void coreCtxInit(u32 coreId, bool isBootCore, u64 argument)
         currentCoreCtx->kernelEntrypoint = g_initialKernelEntrypoint;
     }
 }
+
+void setCurrentCoreActive(void)
+{
+    atomic_fetch_or(&g_activeCoreMask, BIT(currentCoreCtx->coreId));
+}
+
+u32 getActiveCoreMask(void)
+{
+    return (u32)atomic_load(&g_activeCoreMask);
+}
diff --git a/thermosphere/src/core_ctx.h b/thermosphere/src/core_ctx.h
index d37fd83a1..8da5fac3a 100644
--- a/thermosphere/src/core_ctx.h
+++ b/thermosphere/src/core_ctx.h
@@ -16,6 +16,7 @@
 
 #pragma once
 #include "utils.h"
+#include "barrier.h"
 
 typedef struct CoreCtx {
     u64 kernelArgument;             // @0x00
@@ -26,9 +27,16 @@ typedef struct CoreCtx {
     u8 gicInterfaceId;              // @0x24
     bool isBootCore;                // @0x25
     bool warmboot;                  // @0x26
+
+    // "Execute function"
+    void *asyncFunctionArgs;        // @0x28
+    Barrier asyncFunctionBarrier;   // @0x30
 } CoreCtx;
 
 extern CoreCtx g_coreCtxs[4];
 register CoreCtx *currentCoreCtx asm("x18");
 
 void coreCtxInit(u32 coreId, bool isBootCore, u64 argument);
+
+void setCurrentCoreActive(void);
+u32 getActiveCoreMask(void);
diff --git a/thermosphere/src/irq.c b/thermosphere/src/irq.c
index 8e936f1b1..48a09cd0f 100644
--- a/thermosphere/src/irq.c
+++ b/thermosphere/src/irq.c
@@ -37,9 +37,7 @@ static void initGic(void)
         g_irqManager.gic.gicd->ipriorityr[0] = 0xFF;
         g_irqManager.numPriorityLevels = (u8)BIT(__builtin_popcount(g_irqManager.gic.gicd->ipriorityr[0]));
 
-        // same thing for CPU interfaces targets (save for ITARGETSR registers corresponding to SGIs)
-        g_irqManager.gic.gicd->itargetsr[32] = 0xFF;
-        g_irqManager.numCpuInterfaces = (u8)__builtin_popcount(g_irqManager.gic.gicd->itargetsr[32]);
+        g_irqManager.numCpuInterfaces = (u8)(1 + ((g_irqManager.gic.gicd->typer >> 5) & 7));
     }
 
     volatile ArmGicV2Controller *gicc = g_irqManager.gic.gicc;
@@ -60,12 +58,11 @@ static void initGic(void)
 
     // Note: the GICD I...n regs are banked for private interrupts
 
-    // Disable all interrupts, clear active status, clear pending status, also clear secure regs igroupr to be sure
+    // Disable all interrupts, clear active status, clear pending status
     for (u32 i = 0; i < numInterrupts / 32; i++) {
         gicd->icenabler[i] = 0xFFFFFFFF;
         gicd->icactiver[i] = 0xFFFFFFFF;
         gicd->icpendr[i] = 0xFFFFFFFF;
-        gicd->igroupr[i] = 0x00000000;
     }
 
     // Set priorities to lowest
diff --git a/thermosphere/src/irq.h b/thermosphere/src/irq.h
index 0f21ebb7b..2578c677d 100644
--- a/thermosphere/src/irq.h
+++ b/thermosphere/src/irq.h
@@ -30,27 +30,33 @@ typedef struct IrqManager {
     // Note: we don't store interrupt handlers since we will handle some SGI + uart interrupt(s)...
 } IrqManager;
 
+typedef enum ThermosphereSgi {
+    ThermosphereSgi_ExecuteFunction = 0,
+
+    ThermosphereSgi_Max = 1,
+} ThermosphereSgi;
+
 extern IrqManager g_irqManager;
 
 void initIrq(void);
 void handleIrqException(ExceptionStackFrame *frame, bool isLowerEl, bool isA32);
 
-static inline void generateSgiForAllOthers(u32 id)
+static inline void generateSgiForAllOthers(ThermosphereSgi id)
 {
-    g_irqManager.gic.gicd->sgir = (1 << 24) | (id & 0xF);
+    g_irqManager.gic.gicd->sgir = (1 << 24) | ((u32)id & 0xF);
 }
 
-static inline void generateSgiForSelf(u32 id)
+static inline void generateSgiForSelf(ThermosphereSgi id)
 {
-    g_irqManager.gic.gicd->sgir = (2 << 24) | (id & 0xF);
+    g_irqManager.gic.gicd->sgir = (2 << 24) | ((u32)id & 0xF);
 }
 
-static inline void generateSgiForList(u32 id, u32 list)
+static inline void generateSgiForList(ThermosphereSgi id, u32 list)
 {
-    g_irqManager.gic.gicd->sgir = (0 << 24) | (list << 16) | (id & 0xF);
+    g_irqManager.gic.gicd->sgir = (0 << 24) | (list << 16) | ((u32)id & 0xF);
 }
 
-static inline void generateSgiForAll(u32 id)
+static inline void generateSgiForAll(ThermosphereSgi id)
 {
     generateSgiForList(id, MASK(g_irqManager.numCpuInterfaces));
 }
diff --git a/thermosphere/src/main.c b/thermosphere/src/main.c
index c1b9b3895..1db76a20a 100644
--- a/thermosphere/src/main.c
+++ b/thermosphere/src/main.c
@@ -75,10 +75,12 @@ void main(ExceptionStackFrame *frame)
     frame->elr_el2  = currentCoreCtx->kernelEntrypoint;
     frame->x[0]     = currentCoreCtx->kernelArgument;
 
+    setCurrentCoreActive();
+
     // Test
     singleStepSetNextState(frame, SingleStepState_ActivePending);
 
-    // Test
+    /*// Test
     unmaskIrq();
-    generateSgiForAll(0);
+    generateSgiForAll(0);*/
 }