arm/arm64: smccc: Add SMCCC-specific return codes

commit eff0e9e1078ea7dc1d794dc50e31baef984c46d7 upstream.

We've so far used the PSCI return codes for SMCCC because they
were extremely similar. But with the new ARM DEN 0070A specification,
"NOT_REQUIRED" (-2) is clashing with PSCI's "PSCI_RET_INVALID_PARAMS".

Let's bite the bullet and add SMCCC specific return codes. Users
can be repainted as and when required.

Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index a031897..c89da86 100644 (file)
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -291,5 +291,10 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
  */
 #define arm_smccc_1_1_hvc(...) __arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__)
 
+/* Return codes defined in ARM DEN 0070A */
+#define SMCCC_RET_SUCCESS                      0
+#define SMCCC_RET_NOT_SUPPORTED                        -1
+#define SMCCC_RET_NOT_REQUIRED                 -2
+
 #endif /*__ASSEMBLY__*/
 #endif /*__LINUX_ARM_SMCCC_H*/