RISC-V: replace cbom instructions with an insn-def

Using the cbom instructions directly in ALT_CMO_OP, requires toolchain
support for the instructions. Using an insn-def will allow for removal
of toolchain version checks in the build system & simplification of the
proposed [1] function-based CMO scheme.

Link: https://lore.kernel.org/linux-riscv/fb3b34ae-e35e-4dc2-a8f4-19984a2f58a8@app.fastmail.com/ [1]
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20230108163356.3063839-3-conor@kernel.orgSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/include/asm/errata_list.h

@@ -7,6 +7,7 @@
 
 #include <asm/alternative.h>
 #include <asm/csr.h>
+#include <asm/insn-def.h>
 #include <asm/vendorid_list.h>
 
 #ifdef CONFIG_ERRATA_SIFIVE
@@ -125,7 +126,7 @@ asm volatile(ALTERNATIVE_2(						\
 	"mv a0, %1\n\t"							\
 	"j 2f\n\t"							\
 	"3:\n\t"							\
-	"cbo." __stringify(_op) " (a0)\n\t"				\
+	CBO_##_op(a0)							\
 	"add a0, a0, %0\n\t"						\
 	"2:\n\t"							\
 	"bltu a0, %2, 3b\n\t"						\

arch/riscv/include/asm/insn-def.h

@@ -180,4 +180,16 @@
 	INSN_R(OPCODE_SYSTEM, FUNC3(0), FUNC7(51),		\
 	       __RD(0), RS1(gaddr), RS2(vmid))
 
+#define CBO_inval(base)						\
+	INSN_I(OPCODE_MISC_MEM, FUNC3(2), __RD(0),		\
+	       RS1(base), SIMM12(0))
+
+#define CBO_clean(base)						\
+	INSN_I(OPCODE_MISC_MEM, FUNC3(2), __RD(0),		\
+	       RS1(base), SIMM12(1))
+
+#define CBO_flush(base)						\
+	INSN_I(OPCODE_MISC_MEM, FUNC3(2), __RD(0),		\
+	       RS1(base), SIMM12(2))
+
 #endif /* __ASM_INSN_DEF_H */