imx: Support i.MX91 11x11 EVK board

Add i.MX91 11x11 EVK Board support.
 - Four ddr scripts included w/o inline ecc feature.
 - SDHC/NETWORK/I2C/UART supported
 - PCA9451 supported, default nominal drive mode
 - Documentation added.

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/board/freescale/imx91_evk/imx91_evk.env b/board/freescale/imx91_evk/imx91_evk.env
new file mode 100644
index 0000000..92486c6
--- /dev/null
+++ b/board/freescale/imx91_evk/imx91_evk.env
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+
+boot_targets=mmc0 mmc1
+boot_fit=no
+bootm_size=0x10000000
+cntr_addr=0x98000000
+cntr_file=os_cntr_signed.bin
+console=ttyLP0,115200 earlycon
+fdt_addr_r=0x83000000
+fdt_addr=0x83000000
+fdtfile=CONFIG_DEFAULT_FDT_FILE
+image=Image
+mmcpart=1
+mmcroot=/dev/mmcblk1p2 rootwait rw
+mmcautodetect=yes
+mmcargs=setenv bootargs ${jh_clk} ${mcore_clk} console=${console} root=${mmcroot}
+prepare_mcore=setenv mcore_clk clk-imx93.mcore_booted
+loadimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${image}
+loadfdt=fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr_r} ${fdtfile}
+loadcntr=fatload mmc ${mmcdev}:${mmcpart} ${cntr_addr} ${cntr_file}
+auth_os=auth_cntr ${cntr_addr}
+boot_os=booti ${loadaddr} - ${fdt_addr_r}
+mmcboot=
+	echo Booting from mmc ...;
+	run mmcargs;
+	if test ${sec_boot} = yes; then
+		if run auth_os; then
+			run boot_os;
+		else
+			echo ERR: failed to authenticate;
+		fi;
+	else
+		if run loadfdt; then
+			run boot_os;
+		else
+			echo WARN: Cannot load the DT;
+		fi;
+	fi;
+netargs=setenv bootargs ${jh_clk} ${mcore_clk} console=${console} root=/dev/nfs
+	ip=dhcp nfsroot=${serverip}:${nfsroot},v3,tcp
+netboot=
+	echo Booting from net ...;
+	run netargs;
+	if test ${ip_dyn} = yes; then
+		setenv get_cmd dhcp;
+	else
+		setenv get_cmd tftp;
+	fi;
+	if test ${sec_boot} = yes; then
+		${get_cmd} ${cntr_addr} ${cntr_file};
+		if run auth_os; then
+			run boot_os;
+		else
+			echo ERR: failed to authenticate;
+		fi;
+	else
+		${get_cmd} ${loadaddr} ${image};
+		if ${get_cmd} ${fdt_addr_r} ${fdtfile}; then
+			run boot_os;
+		else
+			echo WARN: Cannot load the DT;
+		fi;
+	fi;