rcar_gen3: drivers: delay: Rewrite from assembler to C
Rewrite the delay code from assembler to C.
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
diff --git a/drivers/renesas/rcar/delay/micro_delay.c b/drivers/renesas/rcar/delay/micro_delay.c
new file mode 100644
index 0000000..aced589
--- /dev/null
+++ b/drivers/renesas/rcar/delay/micro_delay.c
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2018, Renesas Electronics Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <arch_helpers.h>
+#include "micro_delay.h"
+
+#define RCAR_CONV_MICROSEC 1000000U
+
+void
+#if IMAGE_BL31
+ __attribute__ ((section (".system_ram")))
+#endif
+ rcar_micro_delay(uint64_t micro_sec)
+{
+ uint64_t freq;
+ uint64_t base_count;
+ uint64_t get_count;
+ uint64_t wait_time = 0U;
+
+ freq = read_cntfrq_el0();
+ base_count = read_cntpct_el0();
+ while (micro_sec > wait_time) {
+ get_count = read_cntpct_el0();
+ wait_time = ((get_count - base_count) * RCAR_CONV_MICROSEC) / freq;
+ }
+}