feat(core): implement svc shutdown

core/embed/firmware/main.c

@@ -49,6 +49,9 @@
 #include "supervise.h"
 #include "touch.h"
 
+// from util.s
+extern void shutdown_privileged(void);
+
 int main(void) {
   random_delays_init();
 
@@ -180,6 +183,11 @@ void SVC_C_Handler(uint32_t *stack) {
       cyccnt_cycles = *DWT_CYCCNT_ADDR;
       break;
 #endif
+    case SVC_SHUTDOWN:
+      shutdown_privileged();
+      for (;;)
+        ;
+      break;
     default:
       stack[0] = 0xffffffff;
       break;

core/embed/trezorhal/supervise.h

@@ -3,6 +3,10 @@
 #define SVC_ENABLE_IRQ 0
 #define SVC_DISABLE_IRQ 1
 #define SVC_SET_PRIORITY 2
+#define SVC_SHUTDOWN 4
+
+// from util.s
+extern void shutdown_privileged(void);
 
 static inline uint32_t is_mode_unprivileged(void) {
   uint32_t r0;
@@ -38,3 +42,11 @@ static inline void svc_setpriority(uint32_t IRQn, uint32_t priority) {
     NVIC_SetPriority(IRQn, priority);
   }
 }
+
+static inline void svc_shutdown(void) {
+  if (is_mode_unprivileged()) {
+    __asm__ __volatile__("svc %0" ::"i"(SVC_SHUTDOWN) : "memory");
+  } else {
+    shutdown_privileged();
+  }
+}