ARM: imx: Enable instruction cache early on on i.MX8M

Enable instruction cache early on to speed up the boot process on i.MX8M.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c
index 75559e3..ef5add0 100644
--- a/arch/arm/mach-imx/imx8m/soc.c
+++ b/arch/arm/mach-imx/imx8m/soc.c
@@ -551,6 +551,11 @@
 int arch_cpu_init(void)
 {
 	struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR;
+
+#if !CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
+	icache_enable();
+#endif
+
 	/*
 	 * ROM might disable clock for SCTR,
 	 * enable the clock before timer_init.