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LibrePilot/flight/PiOS/Common/pios_flashfs_objlist.c
James Cotton 010f0255a4 OP-543: When the magic header on file system is bad at init, read multiple
times.  It's not written as cleanly as I'd like but works for wiping when magic
value changes.  Testing will reveal if this stops the lost settings.
2011-07-04 21:44:41 -05:00

346 lines
9.9 KiB
C

/**
******************************************************************************
*
* @addtogroup PIOS PIOS Core hardware abstraction layer
* @{
* @addtogroup PIOS_FLASHFS_OBJLIST Object list based flash filesystem (low ram)
* @{
*
* @file pios_flashfs_objlist.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
* @brief A file system for storing UAVObject in flash chip
* @see The GNU Public License (GPL) Version 3
*
*****************************************************************************/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "openpilot.h"
#include "uavobjectmanager.h"
// Private functions
static int32_t PIOS_FLASHFS_CleabObjectTableHeader();
static int32_t PIOS_FLASHFS_GetObjAddress(uint32_t objId, uint16_t instId);
static int32_t PIOS_FLASHFS_GetNewAddress(uint32_t objId, uint16_t instId);
// Private variables
static int32_t numObjects = -1;
// Private structures
// Header for objects in the file system table
struct objectHeader {
uint32_t objMagic;
uint32_t objId;
uint32_t instId;
uint32_t address;
} __attribute__((packed));;
struct fileHeader {
uint32_t id;
uint16_t instId;
uint16_t size;
} __attribute__((packed));
#define OBJECT_TABLE_MAGIC 0x85FB3C34
#define OBJ_MAGIC 0x3015AE71
#define OBJECT_TABLE_START 0x00000010
#define OBJECT_TABLE_END 0x00001000
#define SECTOR_SIZE 0x00001000
#define MAX_BADMAGIC 4
/**
* @brief Initialize the flash object setting FS
* @return 0 if success, -1 if failure
*/
int32_t PIOS_FLASHFS_Init()
{
// Check for valid object table or create one
uint32_t object_table_magic;
uint8_t magic_fail_count = 0;
bool magic_good = 0;
while(!magic_good) {
if (PIOS_Flash_W25X_ReadData(0, (uint8_t *)&object_table_magic, sizeof(object_table_magic)) != 0)
return -1;
if(object_table_magic != OBJECT_TABLE_MAGIC) {
if(magic_fail_count++ > MAX_BADMAGIC) {
if(PIOS_FLASHFS_CleabObjectTableHeader() < 0)
return -1;
magic_good = true;
} else {
PIOS_DELAY_WaituS(100);
}
}
else {
magic_good = true;
}
}
int32_t addr = OBJECT_TABLE_START;
struct objectHeader header;
numObjects = 0;
// Loop through header area while objects detect to count how many saved
while(addr < OBJECT_TABLE_END) {
// Read the instance data
if (PIOS_Flash_W25X_ReadData(addr, (uint8_t *)&header, sizeof(header)) != 0)
return -1;
// Counting number of valid headers
if(header.objMagic != OBJ_MAGIC)
break;
numObjects++;
addr += sizeof(header);
}
return 0;
}
/**
* @brief Erase the headers for all objects in the flash chip
* @return 0 if successful, -1 if not
*/
static int32_t PIOS_FLASHFS_CleabObjectTableHeader()
{
if(PIOS_Flash_W25X_EraseSector(0) != 0)
return -1;
uint32_t object_table_magic = OBJECT_TABLE_MAGIC;
if (PIOS_Flash_W25X_WriteData(0, (uint8_t *)&object_table_magic, sizeof(object_table_magic)) != 0)
return -1;
return 0;
}
/**
* @brief Get the address of an object
* @param obj UAVObjHandle for that object
* @parma instId Instance id for that object
* @return address if successful, -1 if not found
*/
static int32_t PIOS_FLASHFS_GetObjAddress(uint32_t objId, uint16_t instId)
{
int32_t addr = OBJECT_TABLE_START;
struct objectHeader header;
// Loop through header area while objects detect to count how many saved
while(addr < OBJECT_TABLE_END) {
// Read the instance data
if (PIOS_Flash_W25X_ReadData(addr, (uint8_t *) &header, sizeof(header)) != 0)
return -1;
if(header.objMagic != OBJ_MAGIC)
break; // stop searching once hit first non-object header
else if (header.objId == objId && header.instId == instId)
break;
addr += sizeof(header);
}
if (header.objId == objId && header.instId == instId)
return header.address;
return -1;
}
/**
* @brief Returns an address for a new object and creates entry into object table
* @param[in] obj Object handle for object to be saved
* @param[in] instId The instance id of object to be saved
* @return 0 if success or error code
* @retval -1 Object not found
* @retval -2 No room in object table
* @retval -3 Unable to write entry into object table
* @retval -4 FS not initialized
*/
int32_t PIOS_FLASHFS_GetNewAddress(uint32_t objId, uint16_t instId)
{
struct objectHeader header;
if(numObjects < 0)
return -4;
// Don't worry about max size of flash chip here, other code will catch that
header.objMagic = OBJ_MAGIC;
header.objId = objId;
header.instId = instId;
header.address = OBJECT_TABLE_END + SECTOR_SIZE * numObjects;
int32_t addr = OBJECT_TABLE_START + sizeof(header) * numObjects;
// No room for this header in object table
if((addr + sizeof(header)) > OBJECT_TABLE_END)
return -2;
if(PIOS_Flash_W25X_WriteData(addr, (uint8_t *) &header, sizeof(header)) != 0)
return -3;
// This numObejcts value must stay consistent or there will be a break in the table
// and later the table will have bad values in it
numObjects++;
return header.address;
}
/**
* @brief Saves one object instance per sector
* @param[in] obj UAVObjHandle the object to save
* @param[in] instId The instance of the object to save
* @return 0 if success or -1 if failure
* @note This uses one sector on the flash chip per object so that no buffering in ram
* must be done when erasing the sector before a save
*/
int32_t PIOS_FLASHFS_ObjSave(UAVObjHandle obj, uint16_t instId, uint8_t * data)
{
uint32_t objId = UAVObjGetID(obj);
uint8_t crc = 0;
int32_t addr = PIOS_FLASHFS_GetObjAddress(objId, instId);
// Object currently not saved
if(addr < 0)
addr = PIOS_FLASHFS_GetNewAddress(objId, instId);
// Could not allocate a sector
if(addr < 0)
return -1;
struct fileHeader header = {
.id = objId,
.instId = instId,
.size = UAVObjGetNumBytes(obj)
};
if(PIOS_Flash_W25X_EraseSector(addr) != 0)
return -2;
// Save header
// This information IS redundant with the object table id. Oh well. Better safe than sorry.
if(PIOS_Flash_W25X_WriteData(addr, (uint8_t *) &header, sizeof(header)) != 0)
return -3;
// Update CRC
crc = PIOS_CRC_updateCRC(0, (uint8_t *) &header, sizeof(header));
// Save data
if(PIOS_Flash_W25X_WriteData(addr + sizeof(header), data, UAVObjGetNumBytes(obj)) != 0)
return -4;
// Update CRC
crc = PIOS_CRC_updateCRC(crc, (uint8_t *) data, UAVObjGetNumBytes(obj));
// Save CRC (written so will work when CRC changes to uint16)
if(PIOS_Flash_W25X_WriteData(addr + sizeof(header) + UAVObjGetNumBytes(obj), (uint8_t *) &crc, sizeof(crc)) != 0)
return -4;
return 0;
}
/**
* @brief Load one object instance per sector
* @param[in] obj UAVObjHandle the object to save
* @param[in] instId The instance of the object to save
* @return 0 if success or error code
* @retval -1 if object not in file table
* @retval -2 if unable to retrieve object header
* @retval -3 if loaded data instId or objId don't match
* @retval -4 if unable to retrieve instance data
* @retval -5 if unable to read CRC
* @retval -6 if CRC doesn't match
* @note This uses one sector on the flash chip per object so that no buffering in ram
* must be done when erasing the sector before a save
*/
int32_t PIOS_FLASHFS_ObjLoad(UAVObjHandle obj, uint16_t instId, uint8_t * data)
{
uint32_t objId = UAVObjGetID(obj);
uint16_t objSize = UAVObjGetNumBytes(obj);
uint8_t crc = 0;
uint8_t crcFlash = 0;
const uint8_t crc_read_step = 8;
uint8_t crc_read_buffer[crc_read_step];
int32_t addr = PIOS_FLASHFS_GetObjAddress(objId, instId);
// Object currently not saved
if(addr < 0)
return -1;
struct fileHeader header;
// Load header
// This information IS redundant with the object table id. Oh well. Better safe than sorry.
if(PIOS_Flash_W25X_ReadData(addr, (uint8_t *) &header, sizeof(header)) != 0)
return -2;
// Update CRC
crc = PIOS_CRC_updateCRC(0, (uint8_t *) &header, sizeof(header));
if((header.id != objId) || (header.instId != instId))
return -3;
// To avoid having to allocate the RAM for a copy of the object, we read by chunks
// and compute the CRC
for(uint32_t i = 0; i < objSize; i += crc_read_step) {
PIOS_Flash_W25X_ReadData(addr + sizeof(header) + i, crc_read_buffer, crc_read_step);
uint8_t valid_bytes = ((i + crc_read_step) >= objSize) ? objSize - i : crc_read_step;
crc = PIOS_CRC_updateCRC(crc, crc_read_buffer, valid_bytes);
}
// Read CRC (written so will work when CRC changes to uint16)
if(PIOS_Flash_W25X_ReadData(addr + sizeof(header) + objSize, (uint8_t *) &crcFlash, sizeof(crcFlash)) != 0)
return -5;
if(crc != crcFlash)
return -6;
// Read the instance data
if (PIOS_Flash_W25X_ReadData(addr + sizeof(header), data, objSize) != 0)
return -4;
return 0;
}
/**
* @brief Delete object from flash
* @param[in] obj UAVObjHandle the object to save
* @param[in] instId The instance of the object to save
* @return 0 if success or error code
* @retval -1 if object not in file table
* @retval -2 Erase failed
* @note To avoid buffering the file table (1k ram!) the entry in the file table
* remains but destination sector is erased. This will make the load fail as the
* file header won't match the object. At next save it goes back there.
*/
int32_t PIOS_FLASHFS_ObjDelete(UAVObjHandle obj, uint16_t instId)
{
uint32_t objId = UAVObjGetID(obj);
int32_t addr = PIOS_FLASHFS_GetObjAddress(objId, instId);
// Object currently not saved
if(addr < 0)
return -1;
if(PIOS_Flash_W25X_EraseSector(addr) != 0)
return -2;
return 0;
}