[PATCH v3 01/20] riscv: hwprobe: factorize hwprobe ISA extension reporting

[Clément Léger]

Factorize ISA extension reporting by using a macro rather than
copy/pasting extension names. This will allow adding new extensions more
easily.

Signed-off-by: Clément Léger <cleger at rivosinc.com>
Reviewed-by: Evan Green <evan at rivosinc.com>
---
 arch/riscv/kernel/sys_riscv.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/riscv/kernel/sys_riscv.c b/arch/riscv/kernel/sys_riscv.c
index b651ec698a91..49aa4e82797c 100644
--- a/arch/riscv/kernel/sys_riscv.c
+++ b/arch/riscv/kernel/sys_riscv.c
@@ -145,20 +145,24 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 	for_each_cpu(cpu, cpus) {
 		struct riscv_isainfo *isainfo = &hart_isa[cpu];
 
-		if (riscv_isa_extension_available(isainfo->isa, ZBA))
-			pair->value |= RISCV_HWPROBE_EXT_ZBA;
-		else
-			missing |= RISCV_HWPROBE_EXT_ZBA;
-
-		if (riscv_isa_extension_available(isainfo->isa, ZBB))
-			pair->value |= RISCV_HWPROBE_EXT_ZBB;
-		else
-			missing |= RISCV_HWPROBE_EXT_ZBB;
-
-		if (riscv_isa_extension_available(isainfo->isa, ZBS))
-			pair->value |= RISCV_HWPROBE_EXT_ZBS;
-		else
-			missing |= RISCV_HWPROBE_EXT_ZBS;
+#define CHECK_ISA_EXT(__ext)							\
+		do {								\
+			if (riscv_isa_extension_available(isainfo->isa, __ext))	\
+				pair->value |= RISCV_HWPROBE_EXT_##__ext;	\
+			else							\
+				missing |= RISCV_HWPROBE_EXT_##__ext;		\
+		} while (false)
+
+		/*
+		 * Only use CHECK_ISA_EXT() for extensions which are usable by
+		 * userspace with respect to the kernel current configuration.
+		 * For instance, ISA extensions that use float operations
+		 * should not be exposed when CONFIG_FPU is not enabled.
+		 */
+		CHECK_ISA_EXT(ZBA);
+		CHECK_ISA_EXT(ZBB);
+		CHECK_ISA_EXT(ZBS);
+#undef CHECK_ISA_EXT
 	}
 
 	/* Now turn off reporting features if any CPU is missing it. */
-- 
2.42.0