riscv: add parsing for Zaamo and Zalrsc extensions

These 2 new extensions are actually a subset of the A extension which
provides atomic memory operations and load-reserved/store-conditional
instructions.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20240619153913.867263-3-cleger@rivosinc.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

Author: clementleger

arch/riscv/include/asm/hwcap.h

@@ -103,6 +103,8 @@
 #define RISCV_ISA_EXT_ZFBFMIN		94
 #define RISCV_ISA_EXT_ZVFBFMIN		95
 #define RISCV_ISA_EXT_ZVFBFWMA		96
+#define RISCV_ISA_EXT_ZAAMO		97
+#define RISCV_ISA_EXT_ZALRSC		98
 
 #define RISCV_ISA_EXT_XLINUXENVCFG	127
 

arch/riscv/kernel/cpufeature.c

@@ -182,6 +182,11 @@ static int riscv_ext_svadu_validate(const struct riscv_isa_ext_data *data,
 	return 0;
 }
 
+static const unsigned int riscv_a_exts[] = {
+	RISCV_ISA_EXT_ZAAMO,
+	RISCV_ISA_EXT_ZALRSC,
+};
+
 static const unsigned int riscv_zk_bundled_exts[] = {
 	RISCV_ISA_EXT_ZBKB,
 	RISCV_ISA_EXT_ZBKC,
@@ -353,7 +358,7 @@ static const unsigned int riscv_c_exts[] = {
 const struct riscv_isa_ext_data riscv_isa_ext[] = {
 	__RISCV_ISA_EXT_DATA(i, RISCV_ISA_EXT_i),
 	__RISCV_ISA_EXT_DATA(m, RISCV_ISA_EXT_m),
-	__RISCV_ISA_EXT_DATA(a, RISCV_ISA_EXT_a),
+	__RISCV_ISA_EXT_SUPERSET(a, RISCV_ISA_EXT_a, riscv_a_exts),
 	__RISCV_ISA_EXT_DATA(f, RISCV_ISA_EXT_f),
 	__RISCV_ISA_EXT_DATA(d, RISCV_ISA_EXT_d),
 	__RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q),
@@ -373,8 +378,10 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
 	__RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
 	__RISCV_ISA_EXT_DATA(zihpm, RISCV_ISA_EXT_ZIHPM),
 	__RISCV_ISA_EXT_DATA(zimop, RISCV_ISA_EXT_ZIMOP),
+	__RISCV_ISA_EXT_DATA(zaamo, RISCV_ISA_EXT_ZAAMO),
 	__RISCV_ISA_EXT_DATA(zabha, RISCV_ISA_EXT_ZABHA),
 	__RISCV_ISA_EXT_DATA(zacas, RISCV_ISA_EXT_ZACAS),
+	__RISCV_ISA_EXT_DATA(zalrsc, RISCV_ISA_EXT_ZALRSC),
 	__RISCV_ISA_EXT_DATA(zawrs, RISCV_ISA_EXT_ZAWRS),
 	__RISCV_ISA_EXT_DATA(zfa, RISCV_ISA_EXT_ZFA),
 	__RISCV_ISA_EXT_DATA_VALIDATE(zfbfmin, RISCV_ISA_EXT_ZFBFMIN, riscv_ext_f_depends),