riscv: Use wfi instruction for idle task

Update #3433.
2018-07-20 09:07:40 +02:00
parent f5fd8eb9e3
commit c2670deb49
2 changed files with 3 additions and 12 deletions
--- a/cpukit/score/cpu/riscv/cpu.c
+++ b/cpukit/score/cpu/riscv/cpu.c
@@ -204,8 +204,9 @@ uint32_t _CPU_ISR_Get_level( void )

 void *_CPU_Thread_Idle_body( uintptr_t ignored )
 {
-  do {
-  } while (1);
+  while ( true ) {
+    __asm__ volatile ( "wfi" );
+  }

  return NULL;
 }
--- a/cpukit/score/cpu/riscv/include/rtems/score/cpu.h
+++ b/cpukit/score/cpu/riscv/include/rtems/score/cpu.h
@@ -360,16 +360,6 @@ void _CPU_Initialize(
  void
 );

-/*
- *  _CPU_Thread_Idle_body
- *
- *  This routine is the CPU dependent IDLE thread body.
- *
- *  NOTE:  It need only be provided if CPU_PROVIDES_IDLE_THREAD_BODY
- *         is TRUE.
- *
- */
-
 void *_CPU_Thread_Idle_body( uintptr_t ignored );

 /*