Create fimrware/asm directory for assembly optimized stuff.

This dir is suitable for stuff that doesn't fit the target tree, e.g. because
it also builds on hosted or otherwise. It also has a generic subfolder for
fallback C implementations so that not all archs need to provide asm files.

SOURCES should only contain "foo.c" where foo.c includes the specific
<arch>/foo.c files from the subdirs using the preprocessor. This way automatic
selection of asm versions or generic C verion is possible.

For the start, the thread support files are moved, since ASM threads can
be used on hosted platforms as well. Since core_sleep() remains platform
specific it's moved to the corresponding system.h headers.

Change-Id: Iebff272f3407a6eaafeb7656ceb0ae9eca3f7cb9

1 files changed, 14 insertions, 0 deletions

diff --git a/firmware/target/sh/system-target.h b/firmware/target/sh/system-target.h
index 5db9cc071f..a62a024823 100644
--- a/firmware/target/sh/system-target.h
+++ b/firmware/target/sh/system-target.h
@@ -137,4 +137,18 @@ static inline void commit_dcache(void) {}
 static inline void commit_discard_dcache(void) {}
 static inline void commit_discard_idcache(void) {}
 
+/*---------------------------------------------------------------------------
+ * Put core in a power-saving state.
+ *---------------------------------------------------------------------------
+ */
+static inline void core_sleep(void)
+{
+    asm volatile (
+        "and.b  #0x7f, @(r0, gbr) \n" /* Clear SBY (bit 7) in SBYCR */
+        "mov    #0, r1            \n" /* Enable interrupts */
+        "ldc    r1, sr            \n" /* Following instruction cannot be interrupted */
+        "sleep                    \n" /* Execute standby */
+        : : "z"(&SBYCR-GBR) : "r1");
+}
+
 #endif /* SYSTEM_TARGET_H */