riscv: Separate toolchain support dependency from RISCV_ISA_ZACAS

RV64 bpf is going to support ZACAS instructions. Let's separate
toolchain support dependency from RISCV_ISA_ZACAS.

Signed-off-by: Pu Lehui <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Tested-by: Björn Töpel <[email protected]>
Reviewed-by: Björn Töpel <[email protected]>
Acked-by: Björn Töpel <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]

Author: Pu Lehui

arch/riscv/Kconfig

@@ -714,7 +714,6 @@ config TOOLCHAIN_HAS_ZACAS
 
 config RISCV_ISA_ZACAS
 	bool "Zacas extension support for atomic CAS"
-	depends on TOOLCHAIN_HAS_ZACAS
 	depends on RISCV_ALTERNATIVE
 	default y
 	help

arch/riscv/include/asm/cmpxchg.h

@@ -133,6 +133,7 @@
 ({										\
 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&				\
 	    IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&				\
+	    IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZACAS) &&				\
 	    riscv_has_extension_unlikely(RISCV_ISA_EXT_ZABHA) &&		\
 	    riscv_has_extension_unlikely(RISCV_ISA_EXT_ZACAS)) {		\
 		r = o;								\
@@ -180,6 +181,7 @@
 		       r, p, co, o, n)					\
 ({									\
 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&			\
+	    IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZACAS) &&			\
 	    riscv_has_extension_unlikely(RISCV_ISA_EXT_ZACAS)) {	\
 		r = o;							\
 									\
@@ -315,7 +317,7 @@
 	arch_cmpxchg_release((ptr), (o), (n));				\
 })
 
-#if defined(CONFIG_64BIT) && defined(CONFIG_RISCV_ISA_ZACAS)
+#if defined(CONFIG_64BIT) && defined(CONFIG_RISCV_ISA_ZACAS) && defined(CONFIG_TOOLCHAIN_HAS_ZACAS)
 
 #define system_has_cmpxchg128()        riscv_has_extension_unlikely(RISCV_ISA_EXT_ZACAS)
 
@@ -351,7 +353,7 @@ union __u128_halves {
 #define arch_cmpxchg128_local(ptr, o, n)					\
 	__arch_cmpxchg128((ptr), (o), (n), "")
 
-#endif /* CONFIG_64BIT && CONFIG_RISCV_ISA_ZACAS */
+#endif /* CONFIG_64BIT && CONFIG_RISCV_ISA_ZACAS && CONFIG_TOOLCHAIN_HAS_ZACAS */
 
 #ifdef CONFIG_RISCV_ISA_ZAWRS
 /*

arch/riscv/kernel/setup.c

@@ -290,6 +290,7 @@ static void __init riscv_spinlock_init(void)
 
 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZABHA) &&
 	    IS_ENABLED(CONFIG_RISCV_ISA_ZACAS) &&
+	    IS_ENABLED(CONFIG_TOOLCHAIN_HAS_ZACAS) &&
 	    riscv_isa_extension_available(NULL, ZABHA) &&
 	    riscv_isa_extension_available(NULL, ZACAS)) {
 		using_ext = "using Zabha";