ARC: add helpers to sanitize config options

We'll use this macro in coming patches extensively.
Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/include/asm/asserts.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+ */
+#ifndef __ASM_ARC_ASSERTS_H
+#define __ASM_ARC_ASSERTS_H
+
+/* Helpers to sanitize config options. */
+
+void chk_opt_strict(char *opt_name, bool hw_exists, bool opt_ena);
+
+/*
+ * Check required config option:
+ *  - panic in case of OPT enabled but corresponding HW absent.
+ *  - warn in case of OPT disabled but corresponding HW exists.
+*/
+#define CHK_OPT_STRICT(opt_name, hw_exists)				\
+({									\
+	chk_opt_strict(#opt_name, hw_exists, IS_ENABLED(opt_name));	\
+})
+
+#endif /* __ASM_ARC_ASSERTS_H */

arch/arc/kernel/setup.c

@@ -19,6 +19,7 @@
 #include <uapi/linux/mount.h>
 #include <asm/sections.h>
 #include <asm/arcregs.h>
+#include <asm/asserts.h>
 #include <asm/tlb.h>
 #include <asm/setup.h>
 #include <asm/page.h>
@@ -389,11 +390,18 @@ static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len)
 	return buf;
 }
 
+void chk_opt_strict(char *opt_name, bool hw_exists, bool opt_ena)
+{
+	if (hw_exists && !opt_ena)
+		pr_warn(" ! Enable %s for working apps\n", opt_name);
+	else if (!hw_exists && opt_ena)
+		panic("Disable %s, hardware NOT present\n", opt_name);
+}
+
 static void arc_chk_core_config(void)
 {
 	struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()];
-	int saved = 0, present = 0;
-	char *opt_nm = NULL;
+	int present = 0;
 
 	if (!cpu->extn.timer0)
 		panic("Timer0 is not present!\n");
@@ -425,23 +433,14 @@ static void arc_chk_core_config(void)
 	 */
 
 	if (is_isa_arcompact()) {
-		opt_nm = "CONFIG_ARC_FPU_SAVE_RESTORE";
-		saved = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE);
-
 		/* only DPDP checked since SP has no arch visible regs */
 		present = cpu->extn.fpu_dp;
+		CHK_OPT_STRICT(CONFIG_ARC_FPU_SAVE_RESTORE, present);
 	} else {
-		opt_nm = "CONFIG_ARC_HAS_ACCL_REGS";
-		saved = IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS);
-
 		/* Accumulator Low:High pair (r58:59) present if DSP MPY or FPU */
 		present = cpu->extn_mpy.dsp | cpu->extn.fpu_sp | cpu->extn.fpu_dp;
+		CHK_OPT_STRICT(CONFIG_ARC_HAS_ACCL_REGS, present);
 	}
-
-	if (present && !saved)
-		pr_warn("Enable %s for working apps\n", opt_nm);
-	else if (!present && saved)
-		panic("Disable %s, hardware NOT present\n", opt_nm);
 }
 
 /*