--- zzzz-none-000/linux-3.10.107/arch/arm/lib/delay.c	2017-06-27 09:49:32.000000000 +0000
+++ vr9-7490-729/linux-3.10.107/arch/arm/lib/delay.c	2021-11-10 11:53:52.000000000 +0000
@@ -37,6 +37,19 @@
 static const struct delay_timer *delay_timer;
 static bool delay_calibrated;
 
+/*                         
+ * Oh, if only we had a cycle counter...
+ */
+void delay_loop(unsigned long loops)
+{
+        asm volatile(
+        "1:     subs %0, %0, #1 \n"
+        "       bhi 1b          \n"
+        : /* No output */
+        : "r" (loops)
+        );
+}
+
 int read_current_timer(unsigned long *timer_val)
 {
 	if (!delay_timer)
@@ -49,10 +62,19 @@
 
 static void __timer_delay(unsigned long cycles)
 {
-	cycles_t start = get_cycles();
+#if defined(CONFIG_AVM_ENHANCED)
+    unsigned long start;
+    start = delay_timer->read_current_timer();
 
-	while ((get_cycles() - start) < cycles)
+    while ((delay_timer->read_current_timer() - start) < cycles)
 		cpu_relax();
+
+#else/*--- #if defined(CONFIG_AVM_ENHANCED) ---*/
+    /*--- avm: get_cycles() do not use read_current_timer()  ---*/
+    cycles_t start = get_cycles();
+    while ((get_cycles() - start) < cycles)
+	    cpu_relax();
+#endif/*--- #else ---*//*--- #if defined(CONFIG_AVM_ENHANCED) ---*/
 }
 
 static void __timer_const_udelay(unsigned long xloops)
@@ -70,7 +92,7 @@
 void __init register_current_timer_delay(const struct delay_timer *timer)
 {
 	if (!delay_calibrated) {
-		pr_info("Switching to timer-based delay loop\n");
+	    pr_info("Switching to timer-based delay loop\n");
 		delay_timer			= timer;
 		lpj_fine			= timer->freq / HZ;
 
@@ -82,7 +104,7 @@
 
 		delay_calibrated		= true;
 	} else {
-		pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
+	    pr_info("Ignoring duplicate/late registration of read_current_timer delay\n");
 	}
 }
 
@@ -91,3 +113,25 @@
 	delay_calibrated = true;
 	return lpj_fine;
 }
+
+#ifdef ARCH_HAS_READ_CURRENT_TIMER
+/*
+ * Assuming read_current_timer() is monotonically increasing
+ * across calls.
+ */
+void read_current_timer_delay_loop(unsigned long loops)
+{
+        unsigned long bclock = bclock,
+		      now = now;
+
+        read_current_timer(&bclock);
+        do {
+                read_current_timer(&now);
+        } while ((now - bclock) < loops);
+}
+#endif
+
+void set_delay_fn(void (*fn)(unsigned long))
+{
+        arm_delay_ops.delay = fn;
+}