arm: implement generic PSCI reset call for armv8

Add a psci_system_reset() which calls the SYSTEM_RESET function of
PSCI 0.2 and can be used by boards that support it to implement
reset_cpu().

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/arm/cpu/armv8/fwcall.c b/arch/arm/cpu/armv8/fwcall.c
index 9efcc5ada9..079e250cbe 100644
--- a/arch/arm/cpu/armv8/fwcall.c
+++ b/arch/arm/cpu/armv8/fwcall.c
@@ -8,6 +8,7 @@
 #include <config.h>
 #include <version.h>
 #include <asm/macro.h>
+#include <asm/psci.h>
 #include <asm/system.h>
 
 /*
@@ -73,3 +74,18 @@ void smc_call(struct pt_regs *args)
 		  "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15",
 		  "x16", "x17");
 }
+
+void __noreturn psci_system_reset(bool conduit_smc)
+{
+	struct pt_regs regs;
+
+	regs.regs[0] = ARM_PSCI_0_2_FN_SYSTEM_RESET;
+
+	if (conduit_smc)
+		smc_call(&regs);
+	else
+		hvc_call(&regs);
+
+	while (1)
+		;
+}