1 files changed, 62 insertions, 0 deletions
diff --git a/chip/stm32/dfu_bootmanager_shared.h b/chip/stm32/dfu_bootmanager_shared.h
new file mode 100644
index 0000000000..4003583ee2
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+++ b/chip/stm32/dfu_bootmanager_shared.h
@@ -0,0 +1,62 @@
+/* Copyright 2022 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.
+ *
+ * DFU Boot Manager shared utilities for STM32
+ *
+ * These of utilities required by the Boot Manager Main and RW Application.
+ * These allow the systems to start the sequence to enter DFU, clear the
+ * state, and access the backup registers.
+ */
+
+#ifndef __DFU_BOOTMANAGER_SHARED_H
+#define __DFU_BOOTMANAGER_SHARED_H
+
+#include "common.h"
+
+/* Registers to validate the backup memory region. */
+#define DFU_BOOTMANAGER_VALUE_MASK      0x00FF
+#define DFU_BOOTMANAGER_VALID_MASK      0xFF00
+#define DFU_BOOTMANAGER_VALID_CHECK     0xAA00
+
+#define DFU_BOOTMANAGER_VALUE_CLEAR     0
+#define DFU_BOOTMANAGER_VALUE_DFU       UINT8_MAX
+
+/*
+ * Reset and enter the DFU mode.
+ *
+ * The system will set flags to the backup memory to enter DFU and issue
+ * a reset. The Boot Manager will send the system to DFU mode.
+ *
+ * @return           EC_SUCCESS, or non-zero if error.
+ */
+int dfu_bootmanager_enter_dfu(void);
+
+/*
+ * Clear the DFU Boot Manager backup memory state.
+ *
+ * If the CONFIG_DFU_BOOTMANAGER_MAX_REBOOT_COUNT setting is enabled, this
+ * allows the RW application to clear the counter to indicate the application
+ * is working as expected.
+ */
+void dfu_bootmanager_clear(void);
+
+/*
+ * Write the value to the backup registers and sets the bitmasks
+ * indicating the field is valid.
+ *
+ * @param value  New value to store.
+ */
+void dfu_bootmanager_backup_write(uint8_t value);
+
+/*
+ * Reads the backup registers and performs validation. The value stored
+ * within the VALUE_MASK is returned and the status code indicates
+ * if the valid check passed.
+ *
+ * @param value[out] Value stored within the DFU_BOOTMANAGER_VALUE_MASK
+ * @return           EC_SUCCESS, or non-zero if validation failed.
+ */
+int dfu_bootmanager_backup_read(uint8_t *value);
+
+#endif /* __DFU_BOOTMANAGER_SHARED_H */