score: Add _CPU_Use_thread_local_storage()

At some point during system initialization, the idle threads are created.
Afterwards, the boot processor basically executes within the context of an idle
thread with thread dispatching disabled.  On some architectures, the
thread-local storage area of the associated thread must be set in dedicated
processor registers.  Add the new CPU port function to do this:

void _CPU_Use_thread_local_storage( const Context_Control *context )

Close #4672.

1 files changed, 17 insertions, 0 deletions

diff --git a/cpukit/score/cpu/no_cpu/include/rtems/score/cpuimpl.h b/cpukit/score/cpu/no_cpu/include/rtems/score/cpuimpl.h
index 6f4abfcfc3..1eec4e6b7a 100644
--- a/cpukit/score/cpu/no_cpu/include/rtems/score/cpuimpl.h
+++ b/cpukit/score/cpu/no_cpu/include/rtems/score/cpuimpl.h
@@ -166,6 +166,23 @@ RTEMS_INLINE_ROUTINE void _CPU_Instruction_no_operation( void )
   __asm__ volatile ( "nop" );
 }
 
+/**
+ * @brief Uses the thread-local storage area of the context.
+ *
+ * Some architectures may use dedicated registers to reference the thread-local
+ * storage area of the associated thread.  This function should set these
+ * registers to the values defined by the specified processor context.
+ *
+ * @param context is the processor context defining the thread-local storage
+ *   area to use.
+ */
+RTEMS_INLINE_ROUTINE void _CPU_Use_thread_local_storage(
+  const Context_Control *context
+)
+{
+  (void) context;
+}
+
 #ifdef __cplusplus
 }
 #endif