Changeset 7dc8bf1 in mainline

Timestamp:

2013-01-10T22:33:02Z (11 years ago)

Author:

Jan Vesely <jano.vesely@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

97718a5

Parents:

1f271d9

Message:

arm32: Implement barriers for armv7-a

File:

• kernel/arch/arm32/include/barrier.h (modified) (2 diffs)

kernel/arch/arm32/include/barrier.h

@@ -49 +49 @@
 #define CS_LEAVE_BARRIER()  asm volatile ("" ::: "memory")
 
+#if defined PROCESSOR_ARCH_armv7_a
+/* ARMv7 uses instructions for memory barriers see ARM Architecture reference
+ * manual for details:
+ * DMB: ch. A8.8.43 page A8-376
+ * DSB: ch. A8.8.44 page A8-378
+ * See ch. A3.8.3 page A3-148 for details about memory barrier implementation
+ * and functionality on armv7 architecture.
+ */
+#define memory_barrier()  asm volatile ("dmb" ::: "memory")
+#define read_barrier()    asm volatile ("dsb" ::: "memory")
+#define write_barrier()   asm volatile ("dsb st" ::: "memory")
+#else
 #define memory_barrier()  asm volatile ("" ::: "memory")
 #define read_barrier()    asm volatile ("" ::: "memory")
 #define write_barrier()   asm volatile ("" ::: "memory")
-
+#endif
 /*
  * There are multiple ways ICache can be implemented on ARM machines. Namely
@@ -68 +80 @@
  */
 
-/* Available on both all supported arms,
+#ifdef PROCESSOR_ARCH_armv7_a
+#define smc_coherence(a) asm volatile ( "isb" ::: "memory")
+#define smc_coherence_block(a, l) smc_coherence(a)
+#else
+/* Available on all supported arms,
  * invalidates entire ICache so the written value does not matter. */
+//TODO might be PL1 only on armv5 -
 #define smc_coherence(a) asm volatile ( "mcr p15, 0, r0, c7, c5, 0")
 #define smc_coherence_block(a, l) smc_coherence(a)
+#endif