riscv: cpufeature: add validation for zfa, zfh and zfhmin

These extensions depends on the F one. Add a validation callback
checking for the F extension to be present. Now that extensions are
correctly reported using the F/D presence, we can remove the
has_fpu() check in hwprobe_isa_ext0().

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20250527100001.33284-1-cleger@rivosinc.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Author: clementleger

arch/riscv/kernel/cpufeature.c

@@ -474,10 +474,10 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
 	__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(zfa, RISCV_ISA_EXT_ZFA, riscv_ext_f_depends),
 	__RISCV_ISA_EXT_DATA_VALIDATE(zfbfmin, RISCV_ISA_EXT_ZFBFMIN, riscv_ext_f_depends),
-	__RISCV_ISA_EXT_DATA(zfh, RISCV_ISA_EXT_ZFH),
-	__RISCV_ISA_EXT_DATA(zfhmin, RISCV_ISA_EXT_ZFHMIN),
+	__RISCV_ISA_EXT_DATA_VALIDATE(zfh, RISCV_ISA_EXT_ZFH, riscv_ext_f_depends),
+	__RISCV_ISA_EXT_DATA_VALIDATE(zfhmin, RISCV_ISA_EXT_ZFHMIN, riscv_ext_f_depends),
 	__RISCV_ISA_EXT_DATA(zca, RISCV_ISA_EXT_ZCA),
 	__RISCV_ISA_EXT_DATA_VALIDATE(zcb, RISCV_ISA_EXT_ZCB, riscv_ext_zca_depends),
 	__RISCV_ISA_EXT_DATA_VALIDATE(zcd, RISCV_ISA_EXT_ZCD, riscv_ext_zcd_validate),

arch/riscv/kernel/sys_hwprobe.c

@@ -153,14 +153,12 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 			EXT_KEY(ZVKT);
 		}
 
-		if (has_fpu()) {
-			EXT_KEY(ZCD);
-			EXT_KEY(ZCF);
-			EXT_KEY(ZFA);
-			EXT_KEY(ZFBFMIN);
-			EXT_KEY(ZFH);
-			EXT_KEY(ZFHMIN);
-		}
+		EXT_KEY(ZCD);
+		EXT_KEY(ZCF);
+		EXT_KEY(ZFA);
+		EXT_KEY(ZFBFMIN);
+		EXT_KEY(ZFH);
+		EXT_KEY(ZFHMIN);
 
 		if (IS_ENABLED(CONFIG_RISCV_ISA_SUPM))
 			EXT_KEY(SUPM);