incubator-nuttx/boards/arm/rp2040/common/include/rp2040_uniqueid.h

69 lines
2.6 KiB
C

/****************************************************************************
* boards/arm/rp2040/common/include/rp2040_uniqueid.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#ifndef __BOARDS_ARM_RP2040_COMMON_INCLUDE_RP2040_UNIQUEID_H
#define __BOARDS_ARM_RP2040_COMMON_INCLUDE_RP2040_UNIQUEID_H
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define RP2040_FLASH_ID_SIZE 8
#define RP2040_FLASH_ID_BUFFER_SIZE 13
#define RP2040_FLASH_ID_BUFFER_OFFSET 5
#define RP2040_FLASH_RUID_CMD 0x4b
#ifdef __cplusplus
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: rp2040_uniqueid_initialize
*
* Description:
* The RP2040 doesn't have a unique ID, so we load the ID from the
* connected flash chip. We use the flash ID to seed a simple xorshift
* PRNG. The PRNG then generates CONFIG_BOARDCTL_UNIQUEID_SIZE bytes,
* which we will use as the board's unique ID.
*
* Retrieving the flash id is somewhat slow and complex, so we only do
* this during initialization and store the result for later use.
*
* Assumptions/Limitations:
* This uniqueid implementation requires a flash chip. It should not be
* used on boards without flash.
*
****************************************************************************/
void rp2040_uniqueid_initialize(void);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __BOARDS_ARM_RP2040_COMMON_INCLUDE_RP2040_UNIQUEID_H */