armv7: Add CPU & MP primitive instructions

To configure multi-processors, we need the intrinsic functions to get core ID,
put core into idle state, and to wake up cores.

Change-Id: I87a62dab6efd6c8bb0c8e46373da7c7eb7b16b35
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/65112
Reviewed-on: http://review.coreboot.org/4444
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

1 files changed, 36 insertions, 0 deletions

diff --git a/src/arch/armv7/include/arch/cpu.h b/src/arch/armv7/include/arch/cpu.h
index f8b3005e95..efd2dc9af9 100644
--- a/src/arch/armv7/include/arch/cpu.h
+++ b/src/arch/armv7/include/arch/cpu.h
@@ -48,4 +48,40 @@ struct cpuinfo_arm {
 
 #endif
 
+/* Primitives for CPU and MP cores. */
+
+/* read Main Id register (MIDR) */
+inline static uint32_t read_midr(void)
+{
+	uint32_t value;
+	asm volatile ("mrc p15, 0, %0, c0, c0, 0" : "=r"(value));
+	return value;
+}
+
+/* read Multiprocessor Affinity Register (MPIDR) */
+inline static uint32_t read_mpidr(void)
+{
+	uint32_t value;
+	asm volatile ("mrc p15, 0, %0, c0, c0, 5" : "=r"(value));
+	return value;
+}
+
+/* wait for interrupt. */
+inline static void wfi(void)
+{
+	asm volatile ("wfi" : : : "memory");
+}
+
+/* wait for event. */
+inline static void wfe(void)
+{
+	asm volatile ("wfe");
+}
+
+/* set event (to bring up cores in WFE state). */
+inline static void sev(void)
+{
+	asm volatile ("sev");
+}
+
 #endif /* __ARCH_CPU_H__ */