imx: mx7dsabresd: add command and macros for boot m4 core

Introduce macros and command to support booting M4 core for
i.MX7D SabreSD board.

Signed-off-by: Ye.Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>

include/configs/mx7dsabresd.h

@@ -57,6 +57,29 @@
 #define CONFIG_SUPPORT_EMMC_BOOT	/* eMMC specific */
 #define CONFIG_SYS_MMC_IMG_LOAD_PART	1
 
+#ifdef CONFIG_IMX_BOOTAUX
+/* Set to QSPI1 A flash at default */
+#define CONFIG_SYS_AUXCORE_BOOTDATA 0x60000000
+#define CONFIG_CMD_SETEXPR
+
+#define UPDATE_M4_ENV \
+	"m4image=m4_qspi.bin\0" \
+	"loadm4image=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${m4image}\0" \
+	"update_m4_from_sd=" \
+		"if sf probe 0:0; then " \
+			"if run loadm4image; then " \
+				"setexpr fw_sz ${filesize} + 0xffff; " \
+				"setexpr fw_sz ${fw_sz} / 0x10000; "	\
+				"setexpr fw_sz ${fw_sz} * 0x10000; "	\
+				"sf erase 0x0 ${fw_sz}; " \
+				"sf write ${loadaddr} 0x0 ${filesize}; " \
+			"fi; " \
+		"fi\0" \
+	"m4boot=sf probe 0:0; bootaux "__stringify(CONFIG_SYS_AUXCORE_BOOTDATA)"\0"
+#else
+#define UPDATE_M4_ENV ""
+#endif
+
 #define CONFIG_MFG_ENV_SETTINGS \
 	"mfgtool_args=setenv bootargs console=${console},${baudrate} " \
 		"rdinit=/linuxrc " \
@@ -76,6 +99,7 @@
 		"rootfs part 0 2\0" \
 
 #define CONFIG_EXTRA_ENV_SETTINGS \
+	UPDATE_M4_ENV \
 	CONFIG_MFG_ENV_SETTINGS \
 	CONFIG_DFU_ENV_SETTINGS \
 	"script=boot.scr\0" \