cmd: pxe: support INITRD and FDT selection with FIT

Since the commit d5ba6188dfbf ("cmd: pxe_utils: Check fdtcontroladdr
in label_boot") the FDT or the FDTDIR label is required in extlinux.conf
and the fallback done by bootm command when only the device tree present
in this command parameters is no more performed when FIT is used for
kernel.

When the label FDT or FDTDIR are absent or if the device tree file is
absent, the PXE command in U-Boot uses the default U-Boot device tree
selected by fdtcontroladdr = gd->fdt_blob, it is the "Scenario 3".

With this scenario the bootm FIP fallback is no more possible with
the extlinux.conf when only "kernel" label is present and is a FIP:

  kernel <path>#<conf>[#<extra-conf[#...]]

As the U-Boot FDT is always provided in the third bootm argument,
the device tree found in FIP is not used as fallback, it was done
previously in boot_get_fdt().

This patch adds a new field kernel_label to save the full kernel label.
The FDT bootm parameters use the kernel address (to avoid to load a
second time the same FIP) and the config when this full label is reused
for "fdt" or "initrd" label.

This FIP support in extlinux.conf is restored when the "FDT" label
can be found and select the same FIP (identical file and configuration):

  kernel <path>#<conf>[#<extra-conf[#...]]
  fdt <path>#<conf>[#<extra-conf[#...]]

The patch add also this possibility for initrd.

  initrd <path>#<conf>[#<extra-conf[#...]]

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

1 files changed, 14 insertions, 3 deletions

diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c
index fc453bd539..b59e959f71 100644
--- a/boot/pxe_utils.c
+++ b/boot/pxe_utils.c
@@ -258,6 +258,7 @@ static struct pxe_label *label_create(void)
 static void label_destroy(struct pxe_label *label)
 {
 	free(label->name);
+	free(label->kernel_label);
 	free(label->kernel);
 	free(label->config);
 	free(label->append);
@@ -542,9 +543,11 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 		kernel_addr = fit_addr;
 	}
 
-	if (label->initrd) {
+	/* For FIT, the label can be identical to kernel one */
+	if (label->initrd && !strcmp(label->kernel_label, label->initrd)) {
+		initrd_addr_str =  kernel_addr;
+	} else if (label->initrd) {
 		ulong size;
-
 		if (get_relfile_envaddr(ctx, label->initrd, "ramdisk_addr_r",
 					&size) < 0) {
 			printf("Skipping %s for failure retrieving initrd\n",
@@ -622,8 +625,11 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 	 */
 	bootm_argv[3] = env_get("fdt_addr_r");
 
+	/* For FIT, the label can be identical to kernel one */
+	if (label->fdt && !strcmp(label->kernel_label, label->fdt)) {
+		bootm_argv[3] = kernel_addr;
 	/* if fdt label is defined then get fdt from server */
-	if (bootm_argv[3]) {
+	} else if (bootm_argv[3]) {
 		char *fdtfile = NULL;
 		char *fdtfilefree = NULL;
 
@@ -1164,6 +1170,11 @@ static int parse_label_kernel(char **c, struct pxe_label *label)
 	if (err < 0)
 		return err;
 
+	/* copy the kernel label to compare with FDT / INITRD when FIT is used */
+	label->kernel_label = strdup(label->kernel);
+	if (!label->kernel_label)
+		return -ENOMEM;
+
 	s = strstr(label->kernel, "#");
 	if (!s)
 		return 1;