FlashSimBlockDevice.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2018 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #include "FlashSimBlockDevice.h"
00018 #include "platform/mbed_assert.h"
00019 #include "platform/mbed_critical.h"
00020 #include <algorithm>
00021 #include <stdlib.h>
00022 #include <string.h>
00023 
00024 static const bd_size_t min_blank_buf_size = 32;
00025 
00026 static inline uint32_t align_up(bd_size_t val, bd_size_t size)
00027 {
00028     return (((val - 1) / size) + 1) * size;
00029 }
00030 
00031 FlashSimBlockDevice::FlashSimBlockDevice(BlockDevice *bd, uint8_t erase_value) :
00032     _erase_value(erase_value), _blank_buf_size(0),
00033     _blank_buf(0), _bd(bd), _init_ref_count(0), _is_initialized(false)
00034 {
00035 }
00036 
00037 FlashSimBlockDevice::~FlashSimBlockDevice()
00038 {
00039     deinit();
00040     delete[] _blank_buf;
00041 }
00042 
00043 int FlashSimBlockDevice::init()
00044 {
00045     int err;
00046     uint32_t val = core_util_atomic_incr_u32(&_init_ref_count, 1);
00047 
00048     if (val != 1) {
00049         return BD_ERROR_OK;
00050     }
00051 
00052     err = _bd->init();
00053     if (err) {
00054         goto fail;
00055     }
00056     _blank_buf_size = align_up(min_blank_buf_size, _bd->get_program_size());
00057     if (!_blank_buf) {
00058         _blank_buf = new uint8_t[_blank_buf_size];
00059         MBED_ASSERT(_blank_buf);
00060     }
00061 
00062     _is_initialized = true;
00063     return BD_ERROR_OK;
00064 
00065 fail:
00066     _is_initialized = false;
00067     _init_ref_count = 0;
00068     return err;
00069 }
00070 
00071 int FlashSimBlockDevice::deinit()
00072 {
00073     if (!_is_initialized) {
00074         return BD_ERROR_OK;
00075     }
00076 
00077     uint32_t val = core_util_atomic_decr_u32(&_init_ref_count, 1);
00078 
00079     if (val) {
00080         return BD_ERROR_OK;
00081     }
00082 
00083     _is_initialized = false;
00084     return _bd->deinit();
00085 }
00086 
00087 int FlashSimBlockDevice::sync()
00088 {
00089     if (!_is_initialized) {
00090         return BD_ERROR_DEVICE_ERROR;
00091     }
00092 
00093     return _bd->sync();
00094 }
00095 
00096 bd_size_t FlashSimBlockDevice::get_read_size() const
00097 {
00098     if (!_is_initialized) {
00099         return 0;
00100     }
00101 
00102     return _bd->get_read_size();
00103 }
00104 
00105 bd_size_t FlashSimBlockDevice::get_program_size() const
00106 {
00107     if (!_is_initialized) {
00108         return 0;
00109     }
00110 
00111     return _bd->get_program_size();
00112 }
00113 
00114 bd_size_t FlashSimBlockDevice::get_erase_size() const
00115 {
00116     if (!_is_initialized) {
00117         return 0;
00118     }
00119 
00120     return _bd->get_erase_size();
00121 }
00122 
00123 bd_size_t FlashSimBlockDevice::get_erase_size(bd_addr_t addr) const
00124 {
00125     if (!_is_initialized) {
00126         return 0;
00127     }
00128 
00129     return _bd->get_erase_size(addr);
00130 }
00131 
00132 bd_size_t FlashSimBlockDevice::size() const
00133 {
00134     if (!_is_initialized) {
00135         return 0;
00136     }
00137 
00138     return _bd->size();
00139 }
00140 
00141 int FlashSimBlockDevice::read(void *b, bd_addr_t addr, bd_size_t size)
00142 {
00143     if (!_is_initialized) {
00144         return BD_ERROR_DEVICE_ERROR;
00145     }
00146 
00147     return _bd->read(b, addr, size);
00148 }
00149 
00150 int FlashSimBlockDevice::program(const void *b, bd_addr_t addr, bd_size_t size)
00151 {
00152     MBED_ASSERT(is_valid_program(addr, size));
00153     if (!_is_initialized) {
00154         return BD_ERROR_DEVICE_ERROR;
00155     }
00156 
00157     bd_addr_t curr_addr = addr;
00158     bd_size_t curr_size = size;
00159 
00160     const uint8_t *buf = (const uint8_t *) b;
00161     while (curr_size) {
00162         bd_size_t read_size = std::min(_blank_buf_size, curr_size);
00163         int ret = _bd->read(_blank_buf, curr_addr, read_size);
00164         if (ret) {
00165             return ret;
00166         }
00167         for (bd_size_t i = 0; i < read_size; i++) {
00168             // Allow either programming on blanks or programming the same value
00169             // (as real flash devices do)
00170             if ((_blank_buf[i] != _erase_value) && (_blank_buf[i] != *buf)) {
00171                 return BD_ERROR_NOT_ERASED;
00172             }
00173             buf++;
00174         }
00175         curr_addr += read_size;
00176         curr_size -= read_size;
00177     }
00178 
00179     return _bd->program(b, addr, size);
00180 }
00181 
00182 int FlashSimBlockDevice::erase(bd_addr_t addr, bd_size_t size)
00183 {
00184     MBED_ASSERT(is_valid_erase(addr, size));
00185 
00186     if (!_is_initialized) {
00187         return BD_ERROR_DEVICE_ERROR;
00188     }
00189 
00190     bd_addr_t curr_addr = addr;
00191     bd_size_t curr_size = size;
00192 
00193     memset(_blank_buf, _erase_value, (unsigned int) _blank_buf_size);
00194 
00195     while (curr_size) {
00196         bd_size_t prog_size = std::min(_blank_buf_size, curr_size);
00197         int ret = _bd->program(_blank_buf, curr_addr, prog_size);
00198         if (ret) {
00199             return ret;
00200         }
00201         curr_addr += prog_size;
00202         curr_size -= prog_size;
00203     }
00204 
00205     return BD_ERROR_OK;
00206 }
00207 
00208 int FlashSimBlockDevice::get_erase_value() const
00209 {
00210     return _erase_value;
00211 }