powerpc: Fix build errors with newer binutils

Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian
2.37.90.20220207) the following build error shows up:

  {standard input}: Assembler messages:
  {standard input}:1190: Error: unrecognized opcode: `stbcix'
  {standard input}:1433: Error: unrecognized opcode: `lwzcix'
  {standard input}:1453: Error: unrecognized opcode: `stbcix'
  {standard input}:1460: Error: unrecognized opcode: `stwcix'
  {standard input}:1596: Error: unrecognized opcode: `stbcix'
  ...

Rework to add assembler directives [1] around the instruction. Going
through them one by one shows that the changes should be safe.  Like
__get_user_atomic_128_aligned() is only called in p9_hmi_special_emu(),
which according to the name is specific to power9.  And __raw_rm_read*()
are only called in things that are powernv or book3s_hv specific.

[1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo

Cc: stable@vger.kernel.org
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
[mpe: Make commit subject more descriptive]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220224162215.3406642-2-anders.roxell@linaro.org

diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index beba497..fee979d 100644 (file)
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -359,25 +359,37 @@ static inline void __raw_writeq_be(unsigned long v, volatile void __iomem *addr)
  */
 static inline void __raw_rm_writeb(u8 val, volatile void __iomem *paddr)
 {
-       __asm__ __volatile__("stbcix %0,0,%1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             stbcix %0,0,%1;  \
+                             .machine pop;"
                : : "r" (val), "r" (paddr) : "memory");
 }
 
 static inline void __raw_rm_writew(u16 val, volatile void __iomem *paddr)
 {
-       __asm__ __volatile__("sthcix %0,0,%1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             sthcix %0,0,%1;  \
+                             .machine pop;"
                : : "r" (val), "r" (paddr) : "memory");
 }
 
 static inline void __raw_rm_writel(u32 val, volatile void __iomem *paddr)
 {
-       __asm__ __volatile__("stwcix %0,0,%1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             stwcix %0,0,%1;  \
+                             .machine pop;"
                : : "r" (val), "r" (paddr) : "memory");
 }
 
 static inline void __raw_rm_writeq(u64 val, volatile void __iomem *paddr)
 {
-       __asm__ __volatile__("stdcix %0,0,%1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             stdcix %0,0,%1;  \
+                             .machine pop;"
                : : "r" (val), "r" (paddr) : "memory");
 }
 
@@ -389,7 +401,10 @@ static inline void __raw_rm_writeq_be(u64 val, volatile void __iomem *paddr)
 static inline u8 __raw_rm_readb(volatile void __iomem *paddr)
 {
        u8 ret;
-       __asm__ __volatile__("lbzcix %0,0, %1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             lbzcix %0,0, %1; \
+                             .machine pop;"
                             : "=r" (ret) : "r" (paddr) : "memory");
        return ret;
 }
@@ -397,7 +412,10 @@ static inline u8 __raw_rm_readb(volatile void __iomem *paddr)
 static inline u16 __raw_rm_readw(volatile void __iomem *paddr)
 {
        u16 ret;
-       __asm__ __volatile__("lhzcix %0,0, %1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             lhzcix %0,0, %1; \
+                             .machine pop;"
                             : "=r" (ret) : "r" (paddr) : "memory");
        return ret;
 }
@@ -405,7 +423,10 @@ static inline u16 __raw_rm_readw(volatile void __iomem *paddr)
 static inline u32 __raw_rm_readl(volatile void __iomem *paddr)
 {
        u32 ret;
-       __asm__ __volatile__("lwzcix %0,0, %1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             lwzcix %0,0, %1; \
+                             .machine pop;"
                             : "=r" (ret) : "r" (paddr) : "memory");
        return ret;
 }
@@ -413,7 +434,10 @@ static inline u32 __raw_rm_readl(volatile void __iomem *paddr)
 static inline u64 __raw_rm_readq(volatile void __iomem *paddr)
 {
        u64 ret;
-       __asm__ __volatile__("ldcix %0,0, %1"
+       __asm__ __volatile__(".machine push;   \
+                             .machine power6; \
+                             ldcix %0,0, %1;  \
+                             .machine pop;"
                             : "=r" (ret) : "r" (paddr) : "memory");
        return ret;
 }

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 6331610..4a35423 100644 (file)
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -125,8 +125,11 @@ do {                                                               \
  */
 #define __get_user_atomic_128_aligned(kaddr, uaddr, err)               \
        __asm__ __volatile__(                           \
+               ".machine push\n"                       \
+               ".machine altivec\n"                    \
                "1:     lvx  0,0,%1     # get user\n"   \
                "       stvx 0,0,%2     # put kernel\n" \
+               ".machine pop\n"                        \
                "2:\n"                                  \
                ".section .fixup,\"ax\"\n"              \
                "3:     li %0,%3\n"                     \

diff --git a/arch/powerpc/platforms/powernv/rng.c b/arch/powerpc/platforms/powernv/rng.c
index b438671..e3d44b3 100644 (file)
--- a/arch/powerpc/platforms/powernv/rng.c
+++ b/arch/powerpc/platforms/powernv/rng.c
@@ -43,7 +43,11 @@ static unsigned long rng_whiten(struct powernv_rng *rng, unsigned long val)
        unsigned long parity;
 
        /* Calculate the parity of the value */
-       asm ("popcntd %0,%1" : "=r" (parity) : "r" (val));
+       asm (".machine push;   \
+             .machine power7; \
+             popcntd %0,%1;   \
+             .machine pop;"
+            : "=r" (parity) : "r" (val));
 
        /* xor our value with the previous mask */
        val ^= rng->mask;