[U-Boot] [PATCH v2] arm64: zynqmp: Create fdtfile from compatible string

[Michal Simek]

distro boot expects that fdtfile name is setup for alternative DTB.
Create this file based on the first platform compatible string.
This should ensure that one rootfs can store multiple DTBs for different
boards.
Reflect structure which is used in Linux kernel. It means dtbs are
strored in xilinx folder.

Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

Changes in v2:
- Use xilinx folder.
- Update commit message

 board/xilinx/zynqmp/zynqmp.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/board/xilinx/zynqmp/zynqmp.c b/board/xilinx/zynqmp/zynqmp.c
index a49f2f3e9ebe..0ac9b46b5f4b 100644
--- a/board/xilinx/zynqmp/zynqmp.c
+++ b/board/xilinx/zynqmp/zynqmp.c
@@ -514,6 +514,36 @@ static u32 reset_reason(void)
 	return ret;
 }
 
+static int set_fdtfile(void)
+{
+	char *compatible, *fdtfile;
+	const char *suffix = ".dtb";
+	const char *vendor = "xilinx/";
+
+	if (env_get("fdtfile"))
+		return 0;
+
+	compatible = (char *)fdt_getprop(gd->fdt_blob, 0, "compatible", NULL);
+	if (compatible) {
+		debug("Compatible: %s\n", compatible);
+
+		/* Discard vendor prefix */
+		strsep(&compatible, ",");
+
+		fdtfile = calloc(1, strlen(vendor) + strlen(compatible) +
+				 strlen(suffix) + 1);
+		if (!fdtfile)
+			return -ENOMEM;
+
+		sprintf(fdtfile, "%s%s%s", vendor, compatible, suffix);
+
+		env_set("fdtfile", fdtfile);
+		free(fdtfile);
+	}
+
+	return 0;
+}
+
 int board_late_init(void)
 {
 	u32 reg = 0;
@@ -536,6 +566,10 @@ int board_late_init(void)
 		return 0;
 	}
 
+	ret = set_fdtfile();
+	if (ret)
+		return ret;
+
 	ret = zynqmp_mmio_read((ulong)&crlapb_base->boot_mode, &reg);
 	if (ret)
 		return -EINVAL;
-- 
1.9.1