--- zzzz-none-000/linux-4.1.52/arch/arm/include/asm/system_misc.h	2018-05-28 02:26:45.000000000 +0000
+++ bcm63-7530ax-731/linux-4.1.52/arch/arm/include/asm/system_misc.h	2022-03-02 11:37:12.000000000 +0000
@@ -7,6 +7,9 @@
 #include <linux/linkage.h>
 #include <linux/irqflags.h>
 #include <linux/reboot.h>
+#if defined(CONFIG_BCM_KF_SPECTRE_PATCH) && defined(CONFIG_BCM_SPECTRE_PATCH_ENABLE)
+#include <linux/percpu.h>
+#endif
 
 extern void cpu_init(void);
 
@@ -14,6 +17,22 @@
 extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
 extern void (*arm_pm_idle)(void);
 
+#if defined(CONFIG_BCM_KF_SPECTRE_PATCH) && defined(CONFIG_BCM_SPECTRE_PATCH_ENABLE)
+#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
+typedef void (*harden_branch_predictor_fn_t)(void);
+DECLARE_PER_CPU(harden_branch_predictor_fn_t, harden_branch_predictor_fn);
+static inline void harden_branch_predictor(void)
+{
+	harden_branch_predictor_fn_t fn = per_cpu(harden_branch_predictor_fn,
+						  smp_processor_id());
+	if (fn)
+		fn();
+}
+#else
+#define harden_branch_predictor() do { } while (0)
+#endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */
+#endif /* CONFIG_BCM_KF_SPECTRE_PATCH && CONFIG_BCM_SPECTRE_PATCH_ENABLE */
+
 #define UDBG_UNDEFINED	(1 << 0)
 #define UDBG_SYSCALL	(1 << 1)
 #define UDBG_BADABORT	(1 << 2)