Diff: features/storage/blockdevice/ExhaustibleBlockDevice.cpp

Revision:

0:38ceb79fef03

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/features/storage/blockdevice/ExhaustibleBlockDevice.cpp	Wed Nov 28 15:10:15 2018 +0000
@@ -0,0 +1,193 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2017 ARM Limited
+ *
+ * Licensed 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.
+ */
+
+#include "ExhaustibleBlockDevice.h"
+#include "platform/mbed_critical.h"
+#include "platform/mbed_assert.h"
+
+ExhaustibleBlockDevice::ExhaustibleBlockDevice(BlockDevice *bd, uint32_t erase_cycles)
+    : _bd(bd), _erase_array(NULL), _erase_cycles(erase_cycles), _init_ref_count(0), _is_initialized(false)
+{
+}
+
+ExhaustibleBlockDevice::~ExhaustibleBlockDevice()
+{
+    delete[] _erase_array;
+}
+
+int ExhaustibleBlockDevice::init()
+{
+    int err;
+    uint32_t val = core_util_atomic_incr_u32(&_init_ref_count, 1);
+
+    if (val != 1) {
+        return BD_ERROR_OK;
+    }
+
+    err = _bd->init();
+    if (err) {
+        goto fail;
+    }
+
+    if (!_erase_array) {
+        // can only be allocated after initialization
+        _erase_array = new uint32_t[_bd->size() / _bd->get_erase_size()];
+        for (size_t i = 0; i < _bd->size() / _bd->get_erase_size(); i++) {
+            _erase_array[i] = _erase_cycles;
+        }
+    }
+
+    _is_initialized = true;
+    return BD_ERROR_OK;
+
+fail:
+    _is_initialized = false;
+    _init_ref_count = 0;
+    return err;
+}
+
+int ExhaustibleBlockDevice::deinit()
+{
+    if (!_is_initialized) {
+        return BD_ERROR_OK;
+    }
+
+    core_util_atomic_decr_u32(&_init_ref_count, 1);
+
+    if (_init_ref_count) {
+        return BD_ERROR_OK;
+    }
+
+    // _erase_array is lazily cleaned up in destructor to allow
+    // data to live across de/reinitialization
+    _is_initialized = false;
+    return _bd->deinit();
+}
+
+int ExhaustibleBlockDevice::sync()
+{
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
+    return _bd->sync();
+}
+
+int ExhaustibleBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
+{
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
+    return _bd->read(buffer, addr, size);
+}
+
+int ExhaustibleBlockDevice::program(const void *buffer, bd_addr_t addr, bd_size_t size)
+{
+    MBED_ASSERT(is_valid_program(addr, size));
+
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
+    if (_erase_array[addr / get_erase_size()] == 0) {
+        return 0;
+    }
+
+    return _bd->program(buffer, addr, size);
+}
+
+int ExhaustibleBlockDevice::erase(bd_addr_t addr, bd_size_t size)
+{
+    MBED_ASSERT(is_valid_erase(addr, size));
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
+    bd_size_t eu_size = get_erase_size();
+    while (size) {
+        // use an erase cycle
+        if (_erase_array[addr / eu_size] > 0) {
+            _erase_array[addr / eu_size] -= 1;
+        }
+
+        if (_erase_array[addr / eu_size] > 0) {
+            int  err = _bd->erase(addr, eu_size);
+            if (err) {
+                return err;
+            }
+        }
+
+        addr += eu_size;
+        size -= eu_size;
+    }
+
+    return 0;
+}
+
+bd_size_t ExhaustibleBlockDevice::get_read_size() const
+{
+    if (!_is_initialized) {
+        return 0;
+    }
+
+    return _bd->get_read_size();
+}
+
+bd_size_t ExhaustibleBlockDevice::get_program_size() const
+{
+    if (!_is_initialized) {
+        return 0;
+    }
+
+    return _bd->get_program_size();
+}
+
+bd_size_t ExhaustibleBlockDevice::get_erase_size() const
+{
+    if (!_is_initialized) {
+        return 0;
+    }
+
+    return _bd->get_erase_size();
+}
+
+bd_size_t ExhaustibleBlockDevice::get_erase_size(bd_addr_t addr) const
+{
+    if (!_is_initialized) {
+        return 0;
+    }
+
+    return _bd->get_erase_size(addr);
+}
+
+int ExhaustibleBlockDevice::get_erase_value() const
+{
+    if (!_is_initialized) {
+        return BD_ERROR_DEVICE_ERROR;
+    }
+
+    return _bd->get_erase_value();
+}
+
+bd_size_t ExhaustibleBlockDevice::size() const
+{
+    if (!_is_initialized) {
+        return 0;
+    }
+
+    return _bd->size();
+}