arm/arm64: smccc-1.1: Make return values unsigned long

BugLink: https://bugs.launchpad.net/bugs/1836287
[ Upstream commit 1d8f574708a3fb6f18c85486d0c5217df893c0cf ]

An unfortunate consequence of having a strong typing for the input
values to the SMC call is that it also affects the type of the
return values, limiting r0 to 32 bits and r{1,2,3} to whatever
was passed as an input.

Let's turn everything into "unsigned long", which satisfies the
requirements of both architectures, and allows for the full
range of return values.

Reported-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index ca1d2cc2cdfa09a8a760693b6b3c10e9c3f6a704..5a91ff33720b222a79023504b0393b29ab5aeb8b 100644 (file)
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -199,31 +199,31 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
 
 #define __declare_arg_0(a0, res)                                       \
        struct arm_smccc_res   *___res = res;                           \
-       register u32           r0 asm("r0") = a0;                       \
+       register unsigned long r0 asm("r0") = (u32)a0;                  \
        register unsigned long r1 asm("r1");                            \
        register unsigned long r2 asm("r2");                            \
        register unsigned long r3 asm("r3")
 
 #define __declare_arg_1(a0, a1, res)                                   \
        struct arm_smccc_res   *___res = res;                           \
-       register u32           r0 asm("r0") = a0;                       \
-       register typeof(a1)    r1 asm("r1") = a1;                       \
+       register unsigned long r0 asm("r0") = (u32)a0;                  \
+       register unsigned long r1 asm("r1") = a1;                       \
        register unsigned long r2 asm("r2");                            \
        register unsigned long r3 asm("r3")
 
 #define __declare_arg_2(a0, a1, a2, res)                               \
        struct arm_smccc_res   *___res = res;                           \
-       register u32           r0 asm("r0") = a0;                       \
-       register typeof(a1)    r1 asm("r1") = a1;                       \
-       register typeof(a2)    r2 asm("r2") = a2;                       \
+       register unsigned long r0 asm("r0") = (u32)a0;                  \
+       register unsigned long r1 asm("r1") = a1;                       \
+       register unsigned long r2 asm("r2") = a2;                       \
        register unsigned long r3 asm("r3")
 
 #define __declare_arg_3(a0, a1, a2, a3, res)                           \
        struct arm_smccc_res   *___res = res;                           \
-       register u32           r0 asm("r0") = a0;                       \
-       register typeof(a1)    r1 asm("r1") = a1;                       \
-       register typeof(a2)    r2 asm("r2") = a2;                       \
-       register typeof(a3)    r3 asm("r3") = a3
+       register unsigned long r0 asm("r0") = (u32)a0;                  \
+       register unsigned long r1 asm("r1") = a1;                       \
+       register unsigned long r2 asm("r2") = a2;                       \
+       register unsigned long r3 asm("r3") = a3
 
 #define __declare_arg_4(a0, a1, a2, a3, a4, res)                       \
        __declare_arg_3(a0, a1, a2, a3, res);                           \