--- zzzz-none-000/linux-3.10.107/arch/arm/kernel/fiq.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/arm/kernel/fiq.c	2021-02-04 17:41:59.000000000 +0000
@@ -52,7 +52,8 @@
 		(unsigned)&vector_fiq_offset;		\
 	})
 
-static unsigned long no_fiq_insn;
+static unsigned long dfl_fiq_insn;
+static struct pt_regs dfl_fiq_regs;
 
 /* Default reacquire function
  * - we always relinquish FIQ control
@@ -60,8 +61,15 @@
  */
 static int fiq_def_op(void *ref, int relinquish)
 {
-	if (!relinquish)
-		set_fiq_handler(&no_fiq_insn, sizeof(no_fiq_insn));
+	if (!relinquish) {
+		/* Restore default handler and registers */
+		local_fiq_disable();
+		set_fiq_regs(&dfl_fiq_regs);
+		set_fiq_handler(&dfl_fiq_insn, sizeof(dfl_fiq_insn));
+		local_fiq_enable();
+
+		/* FIXME: notify irq controller to standard enable FIQs */
+	}
 
 	return 0;
 }
@@ -116,7 +124,7 @@
 void release_fiq(struct fiq_handler *f)
 {
 	if (current_fiq != f) {
-		printk(KERN_ERR "%s FIQ trying to release %s FIQ\n",
+		pr_err("%s FIQ trying to release %s FIQ\n",
 		       f->name, current_fiq->name);
 		dump_stack();
 		return;
@@ -150,6 +158,7 @@
 void __init init_FIQ(int start)
 {
 	unsigned offset = FIQ_OFFSET;
-	no_fiq_insn = *(unsigned long *)(0xffff0000 + offset);
+	dfl_fiq_insn = *(unsigned long *)(0xffff0000 + offset);
+	get_fiq_regs(&dfl_fiq_regs);
 	fiq_start = start;
 }