ARM: Provide common header for hard_smp_processor_id()

Provide a common header to read the SMP CPU number from the MPIDR.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 12 insertions, 0 deletions

diff --git a/arch/arm/include/asm/smp_mpidr.h b/arch/arm/include/asm/smp_mpidr.h
new file mode 100644
index 000000000000..7da7105e83e5
--- /dev/null
+++ b/arch/arm/include/asm/smp_mpidr.h
@@ -0,0 +1,12 @@
+#ifndef ASMARM_SMP_MIDR_H
+#define ASMARM_SMP_MIDR_H
+
+#define hard_smp_processor_id()                                         \
+        ({                                                              \
+                unsigned int cpunum;                                    \
+                __asm__("mrc p15, 0, %0, c0, c0, 5\n"                   \
+                        : "=r" (cpunum));                               \
+                cpunum &= 0x0F;                                         \
+        })
+
+#endif