From 98887ab802e4118e7c813e5e052678772fa1b3a8 Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Sat, 30 Jul 2022 15:52:31 -0600
Subject: [PATCH] event: Add an event for device tree fixups

At present there is a confusing array of functions that handle the
device tree fix-ups needed for booting an OS. We should be able to switch
to using events to clean this up.

As a first step, create a new event type and call it from the standard
place.

Note that this event uses the ofnode interface only, since this can
support live tree which is more efficient when making lots of updates.

Signed-off-by: Simon Glass <sjg@chromium.org>
---
 boot/image-fdt.c                 | 11 +++++++++++
 common/event.c                   |  3 +++
 include/event.h                  | 14 ++++++++++++++
 test/py/tests/test_event_dump.py |  1 +
 4 files changed, 29 insertions(+)

diff --git a/boot/image-fdt.c b/boot/image-fdt.c
index 9db2cee994..5e5b24674d 100644
--- a/boot/image-fdt.c
+++ b/boot/image-fdt.c
@@ -21,6 +21,7 @@
 #include <linux/libfdt.h>
 #include <mapmem.h>
 #include <asm/io.h>
+#include <dm/ofnode.h>
 #include <tee/optee.h>
 
 #ifndef CONFIG_SYS_FDT_PAD
@@ -668,6 +669,16 @@ int image_setup_libfdt(bootm_headers_t *images, void *blob,
 			goto err;
 		}
 	}
+	if (CONFIG_IS_ENABLED(EVENT)) {
+		struct event_ft_fixup fixup;
+
+		fixup.tree = oftree_default();
+		ret = event_notify(EVT_FT_FIXUP, &fixup, sizeof(fixup));
+		if (ret) {
+			printf("ERROR: fdt fixup event failed: %d\n", ret);
+			goto err;
+		}
+	}
 
 	/* Delete the old LMB reservation */
 	if (lmb)
diff --git a/common/event.c b/common/event.c
index af1ed4121d..3e34550978 100644
--- a/common/event.c
+++ b/common/event.c
@@ -35,6 +35,9 @@ const char *const type_name[] = {
 
 	/* init hooks */
 	"misc_init_f",
+
+	/* fdt hooks */
+	"ft_fixup",
 };
 
 _Static_assert(ARRAY_SIZE(type_name) == EVT_COUNT, "event type_name size");
diff --git a/include/event.h b/include/event.h
index fb0734ed4e..e8f2f55c63 100644
--- a/include/event.h
+++ b/include/event.h
@@ -10,6 +10,8 @@
 #ifndef __event_h
 #define __event_h
 
+#include <dm/ofnode_decl.h>
+
 /**
  * enum event_t - Types of events supported by U-Boot
  *
@@ -29,6 +31,9 @@ enum event_t {
 	/* Init hooks */
 	EVT_MISC_INIT_F,
 
+	/* Device tree fixups before booting */
+	EVT_FT_FIXUP,
+
 	EVT_COUNT
 };
 
@@ -50,6 +55,15 @@ union event_data {
 	struct event_dm {
 		struct udevice *dev;
 	} dm;
+
+	/**
+	 * struct event_ft_fixup - FDT fixup before booting
+	 *
+	 * @tree: tree to update
+	 */
+	struct event_ft_fixup {
+		oftree tree;
+	} ft_fixup;
 };
 
 /**
diff --git a/test/py/tests/test_event_dump.py b/test/py/tests/test_event_dump.py
index b753e804ac..1700177724 100644
--- a/test/py/tests/test_event_dump.py
+++ b/test/py/tests/test_event_dump.py
@@ -16,5 +16,6 @@ def test_event_dump(u_boot_console):
     out = util.run_and_log(cons, ['scripts/event_dump.py', sandbox])
     expect = '''.*Event type            Id                              Source location
 --------------------  ------------------------------  ------------------------------
+EVT_FT_FIXUP          bootmeth_vbe_simple_ft_fixup    boot/vbe_simple.c:.*
 EVT_MISC_INIT_F       sandbox_misc_init_f             .*arch/sandbox/cpu/start.c:'''
     assert re.match(expect, out, re.MULTILINE) is not None
-- 
2.39.5