fpga: zynq: Correct fpga load when buf is not aligned

When ARCH_DMA_MINALIGN is greater than header size of the bit file, and buf is
not aligned, new_buf address became greater then buf_start address and the
load_word loop corrupts bit file data.

A work around is to decrease new_buf of ARCH_DMA_MINALIGN, it might corrupt data
before buf but permits to load correctly.

Signed-off-by: Stany MARCEL <smarcel@novasys-ingenierie.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/fpga/zynqpl.c b/drivers/fpga/zynqpl.c
index 1effbad..15900c9 100644
--- a/drivers/fpga/zynqpl.c
+++ b/drivers/fpga/zynqpl.c
@@ -187,6 +187,16 @@
 	if ((u32)buf != ALIGN((u32)buf, ARCH_DMA_MINALIGN)) {
 		u32 *new_buf = (u32 *)ALIGN((u32)buf, ARCH_DMA_MINALIGN);
 
+		/*
+		 * This might be dangerous but permits to flash if
+		 * ARCH_DMA_MINALIGN is greater than header size
+		 */
+		if (new_buf > buf_start) {
+			debug("%s: Aligned buffer is after buffer start\n",
+			      __func__);
+			new_buf -= ARCH_DMA_MINALIGN;
+		}
+
 		printf("%s: Align buffer at %x to %x(swap %d)\n", __func__,
 		       (u32)buf_start, (u32)new_buf, swap);