spl: fit: Add support for loading FPGA bitstream

Add support for loading FPGA into the SPL fitImage support. The
mechanism is flexible and allows user to override the actual
function for loading the FPGA itself. This is because on some
systems, the FPGA must be programmed to allow DRAM access, so
loading the full fitImage may not be possible if it contains
the bitstream. Instead, the spl_load_fpga_image() provides all
the tools to load the bitstream in parts while programming it
into the FPGA.

Signed-off-by: Marek Vasut <marex@denx.de>
[trini: Don't always have a branch to print out type]
Signed-off-by: Tom Rini <trini@konsulko.com>

common/spl/spl_fit.c

@@ -140,6 +140,14 @@ static int get_aligned_image_size(struct spl_load_info *info, int data_size,
 	return (data_size + info->bl_len - 1) / info->bl_len;
 }
 
+#ifdef CONFIG_SPL_FPGA_SUPPORT
+__weak int spl_load_fpga_image(struct spl_load_info *info, size_t length,
+			       int nr_sectors, int sector_offset)
+{
+	return 0;
+}
+#endif
+
 /**
  * spl_load_fit_image(): load the image described in a certain FIT node
  * @info:	points to information about the device to load data from
@@ -161,7 +169,7 @@ static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
 			      void *fit, ulong base_offset, int node,
 			      struct spl_image_info *image_info)
 {
-	int offset;
+	int offset, sector_offset;
 	size_t length;
 	int len;
 	ulong size;
@@ -209,9 +217,16 @@ static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
 
 		overhead = get_aligned_image_overhead(info, offset);
 		nr_sectors = get_aligned_image_size(info, length, offset);
+		sector_offset = sector + get_aligned_image_offset(info, offset);
 
-		if (info->read(info,
-			       sector + get_aligned_image_offset(info, offset),
+#ifdef CONFIG_SPL_FPGA_SUPPORT
+		if (type == IH_TYPE_FPGA) {
+			return spl_load_fpga_image(info, length, nr_sectors,
+						   sector_offset);
+		}
+#endif
+
+		if (info->read(info, sector_offset,
 			       nr_sectors, (void *)load_ptr) != nr_sectors)
 			return -EIO;
 
@@ -387,6 +402,20 @@ int spl_load_simple_fit(struct spl_image_info *spl_image,
 		return -1;
 	}
 
+#ifdef CONFIG_SPL_FPGA_SUPPORT
+	node = spl_fit_get_image_node(fit, images, "fpga", 0);
+	if (node >= 0) {
+		/* Load the image and set up the spl_image structure */
+		ret = spl_load_fit_image(info, sector, fit, base_offset, node,
+					 spl_image);
+		if (ret) {
+			printf("%s: Cannot load the FPGA: %i\n", __func__, ret);
+			return ret;
+		}
+		node = -1;
+	}
+#endif
+
 	/*
 	 * Find the U-Boot image using the following search order:
 	 *   - start at 'firmware' (e.g. an ARM Trusted Firmware)