From: Anders Roxell anders.roxell@linaro.org
commit 8667d0d64dd1f84fd41b5897fd87fa9113ae05e3 upstream.
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_002d...
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/include/asm/io.h | 40 ++++++++++++++++++++++++++++------- arch/powerpc/include/asm/uaccess.h | 3 ++ arch/powerpc/platforms/powernv/rng.c | 6 ++++- 3 files changed, 40 insertions(+), 9 deletions(-)
--- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -372,25 +372,37 @@ static inline void __raw_writeq_be(unsig */ 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"); }
@@ -402,7 +414,10 @@ static inline void __raw_rm_writeq_be(u6 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; } @@ -410,7 +425,10 @@ static inline u8 __raw_rm_readb(volatile 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; } @@ -418,7 +436,10 @@ static inline u16 __raw_rm_readw(volatil 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; } @@ -426,7 +447,10 @@ static inline u32 __raw_rm_readl(volatil 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; } --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -217,8 +217,11 @@ extern long __get_user_bad(void); */ #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" \ --- a/arch/powerpc/platforms/powernv/rng.c +++ b/arch/powerpc/platforms/powernv/rng.c @@ -47,7 +47,11 @@ static unsigned long rng_whiten(struct p 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;