spl: fit: Add support for applying DT overlay

doc/uImage.FIT/overlay-fdt-boot.txt is describing how to create FIT
image with DT overlays in it.
Add support for this feature to SPL.

Here is the ZynqMP fragment where dtb points to full DT and dtbo is
overlay which should be applied on the top of dtb.
config {
        description = "ATF with full u-boot overlay";
        firmware = "atf";
        loadables = "uboot";
        fdt = "dtb", "dtbo";
};

The whole feature depends on OF_LIBFDT_OVERLAY which is adding +4kB code
and 0 for platforms which are not enabling this feature.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/Kconfig b/Kconfig
index 46a31f45b9a5f2a5fe3dab7248553f13b7880c91..0edd4ec2b0bd067313c5e3bd2baf7299eef6bbcf 100644 (file)
--- a/Kconfig
+++ b/Kconfig
@@ -444,6 +444,15 @@ config SPL_LOAD_FIT
          particular it can handle selecting from multiple device tree
          and passing the correct one to U-Boot.
 
+config SPL_LOAD_FIT_APPLY_OVERLAY
+       bool "Enable SPL applying DT overlays from FIT"
+       depends on SPL_LOAD_FIT
+       select OF_LIBFDT_OVERLAY
+       help
+         The device tree is loaded from the FIT image. Allow the SPL is to
+         also load device-tree overlays from the FIT image an apply them
+         over the device tree.
+
 config SPL_LOAD_FIT_FULL
        bool "Enable SPL loading U-Boot as a FIT (full fitImage features)"
        select SPL_FIT

diff --git a/common/spl/spl_fit.c b/common/spl/spl_fit.c
index 346f9edaa52d9fac7063dd201ad84b21104ffae9..39e406b237109531ac8348a5b3ad652a11674284 100644 (file)
--- a/common/spl/spl_fit.c
+++ b/common/spl/spl_fit.c
@@ -281,7 +281,7 @@ static int spl_fit_append_fdt(struct spl_image_info *spl_image,
                              void *fit, int images, ulong base_offset)
 {
        struct spl_image_info image_info;
-       int node, ret = 0;
+       int node, ret = 0, index = 0;
 
        /*
         * Use the address following the image as target address for the
@@ -290,7 +290,7 @@ static int spl_fit_append_fdt(struct spl_image_info *spl_image,
        image_info.load_addr = spl_image->load_addr + spl_image->size;
 
        /* Figure out which device tree the board wants to use */
-       node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, 0);
+       node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, index++);
        if (node < 0) {
                debug("%s: cannot find FDT node\n", __func__);
 
@@ -315,8 +315,32 @@ static int spl_fit_append_fdt(struct spl_image_info *spl_image,
 #if !CONFIG_IS_ENABLED(FIT_IMAGE_TINY)
        /* Try to make space, so we can inject details on the loadables */
        ret = fdt_shrink_to_minimum(spl_image->fdt_addr, 8192);
+       if (ret < 0)
+               return ret;
 #endif
-
+       if (CONFIG_IS_ENABLED(LOAD_FIT_APPLY_OVERLAY)) {
+               for (; ; index++) {
+                       node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP,
+                                                     index);
+                       if (node < 0) {
+                               debug("%s: No additional FDT node\n", __func__);
+                               return 0;
+                       }
+
+                       ret = spl_load_fit_image(info, sector, fit, base_offset,
+                                                node, &image_info);
+                       if (ret < 0)
+                               return ret;
+
+                       ret = fdt_overlay_apply_verbose(spl_image->fdt_addr,
+                                                       (void *)image_info.load_addr);
+                       if (ret)
+                               return ret;
+
+                       debug("%s: DT overlay %s applied\n", __func__,
+                             fit_get_name(fit, node, NULL));
+               }
+       }
        return ret;
 }