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/imx_bl31_common.c b/plat/imx/common/imx_bl31_common.c
new file mode 100644
index 0000000..f6d7e24
--- /dev/null
+++ b/plat/imx/common/imx_bl31_common.c
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2023-2024 NXP
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <imx_plat_common.h>
+
+uint32_t plat_get_spsr_for_bl33_entry(void)
+{
+	unsigned long el_status;
+	unsigned long mode;
+	uint32_t spsr;
+
+	/* figure out what mode we enter the non-secure world */
+	el_status = read_id_aa64pfr0_el1() >> ID_AA64PFR0_EL2_SHIFT;
+	el_status &= ID_AA64PFR0_ELX_MASK;
+
+	mode = (el_status) ? MODE_EL2 : MODE_EL1;
+
+	spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
+	return spsr;
+}