feat(imx8ulp): add i.MX8ULP basic support

Add the basic support for i.MX8ULP.

The i.MX 8ULP family of processors features NXP’s advanced
implementation of the dual Arm Cortex-A35 cores alongside
an Arm Cortex-M33. This combined architecture enables the
device to run a rich operating system (such as Linux) on
the Cortex-A35 core and an RTOS (such as FreeRTOS) on the
Cortex-M33 core. It also includes a Cadence Tensilica Fusion
DSP for low-power audio and a HiFi4 DSP for advanced audio
and machine learning applications.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Change-Id: I12df622b95960bcdf7da52e4c66470a700690e36
diff --git a/plat/imx/common/imx8_helpers.S b/plat/imx/common/imx8_helpers.S
index 19293bf..dce556c 100644
--- a/plat/imx/common/imx8_helpers.S
+++ b/plat/imx/common/imx8_helpers.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2024, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -86,6 +86,31 @@
 	ret
 endfunc plat_calc_core_pos
 
+	/* ----------------------------------------------
+	 * function to handle platform specific reset.
+	 * ----------------------------------------------
+	 */
+func plat_reset_handler
+#if defined(PLAT_imx8ulp)
+	mrs	x0, CORTEX_A35_CPUECTLR_EL1
+	orr     x0, x0, #(0x1 << 0)
+	orr     x0, x0, #(0x1 << 3)
+	msr	CORTEX_A35_CPUECTLR_EL1, x0
+
+	mrs	x0, CORTEX_A35_L2ECTLR_EL1
+	orr     x0, x0, #(0x1 << 0)
+	msr	CORTEX_A35_L2ECTLR_EL1, x0
+	isb
+#endif
+	/* enable EL2 cpuectlr RW access */
+	mov	x0, #0x73
+	msr	actlr_el3, x0
+	msr	actlr_el2, x0
+	isb
+
+	ret
+endfunc plat_reset_handler
+
 	/* ---------------------------------------------
 	 * function to get the entrypoint.
 	 * ---------------------------------------------