1 files changed, 59 insertions, 0 deletions
diff --git a/chip/ish/ish_persistent_data.c b/chip/ish/ish_persistent_data.c
new file mode 100644
index 0000000000..c5168475d5
--- /dev/null
+++ b/chip/ish/ish_persistent_data.c
@@ -0,0 +1,59 @@
+/* Copyright 2019 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "common.h"
+#include "config.h"
+#include "hooks.h"
+#include "system.h"
+#include "ish_persistent_data.h"
+
+#define PERSISTENT_DATA_MAGIC 0x49534864 /* "ISHd" */
+
+struct ish_persistent_data ish_persistent_data = {
+	.magic = PERSISTENT_DATA_MAGIC,
+	.reset_flags = RESET_FLAG_POWER_ON,
+	.watchdog_counter = 0,
+	.panic_data = {0},
+};
+
+/*
+ * When AON task firmware is not available (perhaps in the early
+ * stages of bringing up a new board), we have no way to persist data
+ * across reset. Allocate a memory region for "persistent data" which
+ * will never persist, this way we can use ish_persistent_data in a
+ * consistent manner without having to worry if the AON task firmware
+ * is available.
+ *
+ * Otherwise (AON task firmware is available), the
+ * ish_persistent_data_aon symbol is exported by the linker script.
+ */
+#ifdef CONFIG_ISH_PM_AONTASK
+extern struct ish_persistent_data ish_persistent_data_aon;
+#else
+static struct ish_persistent_data ish_persistent_data_aon;
+#endif
+
+void ish_persistent_data_init(void)
+{
+	if (ish_persistent_data_aon.magic == PERSISTENT_DATA_MAGIC) {
+		/* Stored data is valid, load a copy */
+		memcpy(&ish_persistent_data,
+		       &ish_persistent_data_aon,
+		       sizeof(struct ish_persistent_data));
+
+		/* Invalidate stored data, in case commit fails to happen */
+		ish_persistent_data_aon.magic = 0;
+	}
+
+	/* Update the system module's copy of the reset flags */
+	system_set_reset_flags(chip_read_reset_flags());
+}
+
+void ish_persistent_data_commit(void)
+{
+	memcpy(&ish_persistent_data_aon,
+	       &ish_persistent_data,
+	       sizeof(struct ish_persistent_data));
+}