upl: Plumb in universal payload to the init process

Read the UPL early in boot so that it is available. For now none of the
information is used.

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

boot/Kconfig

@@ -763,7 +763,9 @@ config UPL_READ
 	help
 	  Provides support for decoding a UPL-format payload into a C structure
 	  which can be used elsewhere in U-Boot. This is just the reading
-	  implementation, useful for trying it out.
+	  implementation, useful for trying it out. See UPL_IN for how
+	  to tell U-Boot to actually read it on startup and use it for memory
+	  and device information, etc.
 
 config UPL_WRITE
 	bool "upl - Support writing a Universal Payload handoff"
@@ -774,6 +776,14 @@ config UPL_WRITE
 	  for how to tell U-Boot SPL to actually write it before jumping to
 	  the next phase.
 
+config UPL_IN
+	bool "upl - Read the UPL handoff on startup"
+	select UPL_READ
+	help
+	  Read an SPL handoff when U-Boot starts and use it to provide
+	  devices, memory layout, etc. required by U-Boot. This allows U-Boot
+	  to function as a payload in the meaning of the specification.
+
 if SPL
 
 config SPL_UPL

common/board_f.c

@@ -40,6 +40,7 @@
 #include <sysreset.h>
 #include <timer.h>
 #include <trace.h>
+#include <upl.h>
 #include <video.h>
 #include <watchdog.h>
 #include <asm/cache.h>
@@ -859,6 +860,26 @@ __weak int clear_bss(void)
 	return 0;
 }
 
+static int initf_upl(void)
+{
+	struct upl *upl;
+	int ret;
+
+	if (!IS_ENABLED(CONFIG_UPL_IN) || !(gd->flags & GD_FLG_UPL))
+		return 0;
+
+	upl = malloc(sizeof(struct upl));
+	if (upl)
+		ret = upl_read_handoff(upl, oftree_default());
+	if (ret) {
+		printf("UPL handoff: read failure (err=%dE)\n", ret);
+		return ret;
+	}
+	gd_set_upl(upl);
+
+	return 0;
+}
+
 static const init_fnc_t init_sequence_f[] = {
 	setup_mon_len,
 #ifdef CONFIG_OF_CONTROL
@@ -868,6 +889,7 @@ static const init_fnc_t init_sequence_f[] = {
 	trace_early_init,
 #endif
 	initf_malloc,
+	initf_upl,
 	log_init,
 	initf_bootstage,	/* uses its own timer, so does not need DM */
 	event_init,

common/board_r.c

@@ -521,6 +521,8 @@ static int dm_announce(void)
 		       uclass_count);
 		if (CONFIG_IS_ENABLED(OF_REAL))
 			printf(", devicetree: %s", fdtdec_get_srcname());
+		if (CONFIG_IS_ENABLED(UPL))
+			printf(", universal payload active");
 		printf("\n");
 		if (IS_ENABLED(CONFIG_OF_HAS_PRIOR_STAGE) &&
 		    (gd->fdt_src == FDTSRC_SEPARATE ||