riscv: ae350: Fix XIP config boot failure

The booting flow is SPL -> OpenSBI -> U-Boot.
The boot hart may change after OpenSBI and may not always be hart0,
so wrap the related branch instruction with M-MODE.

Current DTB setup for XIP is not valid.
There is no chance for CONFIG_SYS_FDT_BASE, the DTB address used
in XIP mode, to be returned. Fix this.

Fixes: 2e8d2f88439d ("riscv: Remove OF_PRIOR_STAGE from RISC-V boards")
Signed-off-by: Rick Chen <rick@andestech.com>
Signed-off-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S
index ac81783..b7f21ab 100644
--- a/arch/riscv/cpu/start.S
+++ b/arch/riscv/cpu/start.S
@@ -140,9 +140,11 @@
 	 * accesses gd).
 	 */
 	mv	gp, s0
+#if CONFIG_IS_ENABLED(RISCV_MMODE)
 	bnez	tp, secondary_hart_loop
 #endif
-
+#endif
+	
 	mv      a0, s0
 	jal	board_init_f_init_reserve
 
diff --git a/board/AndesTech/ax25-ae350/ax25-ae350.c b/board/AndesTech/ax25-ae350/ax25-ae350.c
index d6a4291..36f0dd4 100644
--- a/board/AndesTech/ax25-ae350/ax25-ae350.c
+++ b/board/AndesTech/ax25-ae350/ax25-ae350.c
@@ -54,17 +54,22 @@
 	return 0;
 }
 
+#define ANDES_HW_DTB_ADDRESS	0xF2000000
 void *board_fdt_blob_setup(int *err)
 {
 	*err = 0;
-#if defined(CONFIG_OF_BOARD)
-	return (void *)(ulong)gd->arch.firmware_fdt_addr;
-#elif defined(CONFIG_OF_SEPARATE)
-	return (void *)CONFIG_SYS_FDT_BASE;
-#else
+
+	if (IS_ENABLED(CONFIG_OF_SEPARATE) || IS_ENABLED(CONFIG_OF_BOARD)) {
+		if (gd->arch.firmware_fdt_addr)
+			return (void *)(ulong)gd->arch.firmware_fdt_addr;
+	}
+
+	if (fdt_magic(CONFIG_SYS_FDT_BASE) == FDT_MAGIC)
+		return (void *)CONFIG_SYS_FDT_BASE;
+	return (void *)ANDES_HW_DTB_ADDRESS;
+
 	*err = -EINVAL;
 	return NULL;
-#endif
 }
 
 int smc_init(void)