riscv/hwprobe: add zicfilp / zicfiss enumeration in hwprobe

Add enumeration of the zicfilp and zicfiss extensions in the hwprobe syscall.

Reviewed-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Deepak Gupta <debug@rivosinc.com>
Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6
Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com>
Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-20-b55691eacf4f@rivosinc.com
[pjw@kernel.org: updated to apply; extend into RISCV_HWPROBE_KEY_IMA_EXT_1; clean patch description]
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Author: deepak0414

arch/riscv/include/uapi/asm/hwprobe.h

@@ -86,6 +86,7 @@ struct riscv_hwprobe {
 #define		RISCV_HWPROBE_EXT_ZICBOP	(1ULL << 60)
 #define		RISCV_HWPROBE_EXT_ZILSD		(1ULL << 61)
 #define		RISCV_HWPROBE_EXT_ZCLSD		(1ULL << 62)
+#define		RISCV_HWPROBE_EXT_ZICFILP	(1ULL << 63)
 
 #define RISCV_HWPROBE_KEY_CPUPERF_0	5
 #define		RISCV_HWPROBE_MISALIGNED_UNKNOWN	(0 << 0)
@@ -114,6 +115,8 @@ struct riscv_hwprobe {
 #define RISCV_HWPROBE_KEY_VENDOR_EXT_MIPS_0	14
 #define RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE	15
 #define RISCV_HWPROBE_KEY_IMA_EXT_1		16
+#define		RISCV_HWPROBE_EXT_ZICFISS	(1ULL << 0)
+
 /* Increase RISCV_HWPROBE_MAX_KEY when adding items. */
 
 /* Flags */

arch/riscv/kernel/sys_hwprobe.c

@@ -126,6 +126,7 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 		EXT_KEY(isainfo->isa, ZICBOM, pair->value, missing);
 		EXT_KEY(isainfo->isa, ZICBOP, pair->value, missing);
 		EXT_KEY(isainfo->isa, ZICBOZ, pair->value, missing);
+		EXT_KEY(isainfo->isa, ZICFILP, pair->value, missing);
 		EXT_KEY(isainfo->isa, ZICNTR, pair->value, missing);
 		EXT_KEY(isainfo->isa, ZICOND, pair->value, missing);
 		EXT_KEY(isainfo->isa, ZIHINTNTL, pair->value, missing);
@@ -195,15 +196,15 @@ static void hwprobe_isa_ext1(struct riscv_hwprobe *pair,
 	 * doesn't have.
 	 */
 	for_each_cpu(cpu, cpus) {
-		/* struct riscv_isainfo *isainfo = &hart_isa[cpu]; */
+		struct riscv_isainfo *isainfo = &hart_isa[cpu];
 
 		/*
 		 * Only use EXT_KEY() for extensions which can be
 		 * exposed to userspace, regardless of the kernel's
 		 * configuration, as no other checks, besides presence
 		 * in the hart_isa bitmap, are made.
 		 */
-		/* Nothing here yet */
+		EXT_KEY(isainfo->isa, ZICFISS, pair->value, missing);
 	}
 
 	/* Now turn off reporting features if any CPU is missing it. */