riscv: remove CONFIG_RISCV_ISA_A

This option is always enabled, and not supporting the A extensions would
create a complete ABI trainwreck, so there is no point in even slightly
encouraging such an idea by keeping this unselectable code around.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

arch/riscv/Kconfig

@@ -27,7 +27,7 @@ config RISCV
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
 	select GENERIC_SMP_IDLE_THREAD
-	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
+	select GENERIC_ATOMIC64 if !64BIT
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_DMA_CONTIGUOUS
@@ -35,7 +35,6 @@ config RISCV
 	select HAVE_PERF_EVENTS
 	select HAVE_SYSCALL_TRACEPOINTS
 	select IRQ_DOMAIN
-	select RISCV_ISA_A if SMP
 	select SPARSE_IRQ
 	select SYSCTL_EXCEPTION_TRACE
 	select HAVE_ARCH_TRACEHOOK
@@ -197,9 +196,6 @@ config RISCV_ISA_C
 
 	   If you don't know what to do here, say Y.
 
-config RISCV_ISA_A
-	def_bool y
-
 menu "supported PMU type"
 	depends on PERF_EVENTS
 

arch/riscv/Makefile

@@ -39,9 +39,8 @@ endif
 KBUILD_CFLAGS += -Wall
 
 # ISA string setting
-riscv-march-$(CONFIG_ARCH_RV32I)	:= rv32im
-riscv-march-$(CONFIG_ARCH_RV64I)	:= rv64im
-riscv-march-$(CONFIG_RISCV_ISA_A)	:= $(riscv-march-y)a
+riscv-march-$(CONFIG_ARCH_RV32I)	:= rv32ima
+riscv-march-$(CONFIG_ARCH_RV64I)	:= rv64ima
 riscv-march-$(CONFIG_FPU)		:= $(riscv-march-y)fd
 riscv-march-$(CONFIG_RISCV_ISA_C)	:= $(riscv-march-y)c
 KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))

arch/riscv/include/asm/futex.h

@@ -7,18 +7,6 @@
 #ifndef _ASM_FUTEX_H
 #define _ASM_FUTEX_H
 
-#ifndef CONFIG_RISCV_ISA_A
-/*
- * Use the generic interrupt disabling versions if the A extension
- * is not supported.
- */
-#ifdef CONFIG_SMP
-#error "Can't support generic futex calls without A extension on SMP"
-#endif
-#include <asm-generic/futex.h>
-
-#else /* CONFIG_RISCV_ISA_A */
-
 #include <linux/futex.h>
 #include <linux/uaccess.h>
 #include <linux/errno.h>
@@ -124,5 +112,4 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 	return ret;
 }
 
-#endif /* CONFIG_RISCV_ISA_A */
 #endif /* _ASM_FUTEX_H */