bootstd: Tweak bootflow logic for device tree

We should only store the FDT filename if we were able to determine one.
Adjust the logic for this.

This corrects the case where no FDT is needed to boot, such as with EFI
using ACPI.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/boot/bootmeth_efi.c b/boot/bootmeth_efi.c
index 6a97ac0..d7e042c 100644 (file)
--- a/boot/bootmeth_efi.c
+++ b/boot/bootmeth_efi.c
@@ -235,21 +235,21 @@ static int distro_efi_read_bootflow_file(struct udevice *dev,
 
        /* try the various available names */
        ret = -ENOENT;
-       for (seq = 0; ret; seq++) {
+       *fname = '\0';
+       for (seq = 0; ret == -ENOENT; seq++) {
                ret = distro_efi_get_fdt_name(fname, sizeof(fname), seq);
-               if (ret == -EALREADY) {
+               if (ret == -EALREADY)
                        bflow->flags = BOOTFLOWF_USE_PRIOR_FDT;
-                       break;
-               }
-               if (ret)
-                       return log_msg_ret("nam", ret);
-               ret = bootmeth_common_read_file(dev, bflow, fname, fdt_addr,
-                                               &size);
+               if (!ret)
+                       ret = bootmeth_common_read_file(dev, bflow, fname,
+                                                       fdt_addr, &size);
        }
 
-       bflow->fdt_fname = strdup(fname);
-       if (!bflow->fdt_fname)
-               return log_msg_ret("fil", -ENOMEM);
+       if (*fname) {
+               bflow->fdt_fname = strdup(fname);
+               if (!bflow->fdt_fname)
+                       return log_msg_ret("fil", -ENOMEM);
+       }
 
        if (!ret) {
                bflow->fdt_size = size;