Руслан Бредун
test
Diff: mbed/drivers/MbedCRC.h
- Revision:
- 12:406f75196a12
- Parent:
- 11:32eeb052cda5
- Child:
- 13:0c732e06d675
--- a/mbed/drivers/MbedCRC.h Wed Aug 26 14:26:27 2020 +0530
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,563 +0,0 @@
-/* mbed Microcontroller Library
- * Copyright (c) 2018 ARM Limited
- * SPDX-License-Identifier: Apache-2.0
- *
- * 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.
- */
-#ifndef MBED_CRC_API_H
-#define MBED_CRC_API_H
-
-#include "drivers/TableCRC.h"
-#include "hal/crc_api.h"
-#include "platform/mbed_assert.h"
-#include "platform/SingletonPtr.h"
-#include "platform/PlatformMutex.h"
-
-/* This is invalid warning from the compiler for below section of code
-if ((width < 8) && (NULL == _crc_table)) {
- p_crc = (uint32_t)(p_crc << (8 - width));
-}
-Compiler warns of the shift operation with width as it is width=(std::uint8_t),
-but we check for ( width < 8) before performing shift, so it should not be an issue.
-*/
-#if defined ( __CC_ARM )
-#pragma diag_suppress 62 // Shift count is negative
-#elif defined ( __GNUC__ )
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wshift-count-negative"
-#elif defined (__ICCARM__)
-#pragma diag_suppress=Pe062 // Shift count is negative
-#endif
-
-namespace mbed {
-/** \addtogroup drivers */
-/** @{*/
-
-/** CRC object provides CRC generation through hardware/software
- *
- * ROM polynomial tables for supported polynomials (:: crc_polynomial_t) will be used for
- * software CRC computation, if ROM tables are not available then CRC is computed runtime
- * bit by bit for all data input.
- * @note Synchronization level: Thread safe
- *
- * @tparam polynomial CRC polynomial value in hex
- * @tparam width CRC polynomial width
- *
- * Example: Compute CRC data
- * @code
- *
- * #include "mbed.h"
- *
- * int main() {
- * MbedCRC<POLY_32BIT_ANSI, 32> ct;
- *
- * char test[] = "123456789";
- * uint32_t crc = 0;
- *
- * printf("\nPolynomial = 0x%lx Width = %d \n", ct.get_polynomial(), ct.get_width());
- *
- * ct.compute((void *)test, strlen((const char*)test), &crc);
- *
- * printf("The CRC of data \"123456789\" is : 0x%lx\n", crc);
- * return 0;
- * }
- * @endcode
- * Example: Compute CRC with data available in parts
- * @code
- *
- * #include "mbed.h"
- * int main() {
- * MbedCRC<POLY_32BIT_ANSI, 32> ct;
- *
- * char test[] = "123456789";
- * uint32_t crc = 0;
- *
- * printf("\nPolynomial = 0x%lx Width = %d \n", ct.get_polynomial(), ct.get_width());
- * ct.compute_partial_start(&crc);
- * ct.compute_partial((void *)&test, 4, &crc);
- * ct.compute_partial((void *)&test[4], 5, &crc);
- * ct.compute_partial_stop(&crc);
- * printf("The CRC of data \"123456789\" is : 0x%lx\n", crc);
- * return 0;
- * }
- * @endcode
- * @ingroup drivers
- */
-
-extern SingletonPtr<PlatformMutex> mbed_crc_mutex;
-
-template <uint32_t polynomial = POLY_32BIT_ANSI, uint8_t width = 32>
-class MbedCRC {
-
-public:
- enum CrcMode {
-#if DEVICE_CRC
- HARDWARE = 0,
-#endif
- TABLE = 1,
- BITWISE
- };
-
- typedef uint64_t crc_data_size_t;
-
- /** Lifetime of CRC object
- *
- * @param initial_xor Inital value/seed to Xor
- * @param final_xor Final Xor value
- * @param reflect_data
- * @param reflect_remainder
- * @note Default constructor without any arguments is valid only for supported CRC polynomials. :: crc_polynomial_t
- * MbedCRC <POLY_7BIT_SD, 7> ct; --- Valid POLY_7BIT_SD
- * MbedCRC <0x1021, 16> ct; --- Valid POLY_16BIT_CCITT
- * MbedCRC <POLY_16BIT_CCITT, 32> ct; --- Invalid, compilation error
- * MbedCRC <POLY_16BIT_CCITT, 32> ct (i,f,rd,rr) Constructor can be used for not supported polynomials
- * MbedCRC<POLY_16BIT_CCITT, 16> sd(0, 0, false, false); Constructor can also be used for supported
- * polynomials with different intial/final/reflect values
- *
- */
- MbedCRC(uint32_t initial_xor, uint32_t final_xor, bool reflect_data, bool reflect_remainder) :
- _initial_value(initial_xor), _final_xor(final_xor), _reflect_data(reflect_data),
- _reflect_remainder(reflect_remainder)
- {
- mbed_crc_ctor();
- }
- MbedCRC();
- virtual ~MbedCRC()
- {
- // Do nothing
- }
-
- /** Compute CRC for the data input
- * Compute CRC performs the initialization, computation and collection of
- * final CRC.
- *
- * @param buffer Data bytes
- * @param size Size of data
- * @param crc CRC is the output value
- * @return 0 on success, negative error code on failure
- */
- int32_t compute(void *buffer, crc_data_size_t size, uint32_t *crc)
- {
- MBED_ASSERT(crc != NULL);
- int32_t status = 0;
-
- status = compute_partial_start(crc);
- if (0 != status) {
- unlock();
- return status;
- }
-
- status = compute_partial(buffer, size, crc);
- if (0 != status) {
- unlock();
- return status;
- }
-
- status = compute_partial_stop(crc);
- if (0 != status) {
- *crc = 0;
- }
-
- return status;
-
- }
-
- /** Compute partial CRC for the data input.
- *
- * CRC data if not available fully, CRC can be computed in parts with available data.
- *
- * In case of hardware, intermediate values and states are saved by hardware. Mutex
- * locking is used to serialize access to hardware CRC.
- *
- * In case of software CRC, previous CRC output should be passed as argument to the
- * current compute_partial call. Please note the intermediate CRC value is maintained by
- * application and not the driver.
- *
- * @pre: Call `compute_partial_start` to start the partial CRC calculation.
- * @post: Call `compute_partial_stop` to get the final CRC value.
- *
- * @param buffer Data bytes
- * @param size Size of data
- * @param crc CRC value is intermediate CRC value filled by API.
- * @return 0 on success or a negative error code on failure
- * @note: CRC as output in compute_partial is not final CRC value, call `compute_partial_stop`
- * to get final correct CRC value.
- */
- int32_t compute_partial(void *buffer, crc_data_size_t size, uint32_t *crc)
- {
- int32_t status = 0;
-
- switch (_mode) {
-#if DEVICE_CRC
- case HARDWARE:
- hal_crc_compute_partial((uint8_t *)buffer, size);
- *crc = 0;
- break;
-#endif
- case TABLE:
- status = table_compute_partial(buffer, size, crc);
- break;
- case BITWISE:
- status = bitwise_compute_partial(buffer, size, crc);
- break;
- default:
- status = -1;
- break;
- }
-
- return status;
- }
-
- /** Compute partial start, indicate start of partial computation.
- *
- * This API should be called before performing any partial computation
- * with compute_partial API.
- *
- * @param crc Initial CRC value set by the API
- * @return 0 on success or a negative in case of failure
- * @note: CRC is an out parameter and must be reused with compute_partial
- * and `compute_partial_stop` without any modifications in application.
- */
- int32_t compute_partial_start(uint32_t *crc)
- {
- MBED_ASSERT(crc != NULL);
-
-#if DEVICE_CRC
- if (_mode == HARDWARE) {
- lock();
- crc_mbed_config_t config;
- config.polynomial = polynomial;
- config.width = width;
- config.initial_xor = _initial_value;
- config.final_xor = _final_xor;
- config.reflect_in = _reflect_data;
- config.reflect_out = _reflect_remainder;
-
- hal_crc_compute_partial_start(&config);
- }
-#endif
-
- *crc = _initial_value;
- return 0;
- }
-
- /** Get the final CRC value of partial computation.
- *
- * CRC value available in partial computation is not correct CRC, as some
- * algorithms require remainder to be reflected and final value to be XORed
- * This API is used to perform final computation to get correct CRC value.
- *
- * @param crc CRC result
- * @return 0 on success or a negative in case of failure.
- */
- int32_t compute_partial_stop(uint32_t *crc)
- {
- MBED_ASSERT(crc != NULL);
-
-#if DEVICE_CRC
- if (_mode == HARDWARE) {
- *crc = hal_crc_get_result();
- unlock();
- return 0;
- }
-#endif
- uint32_t p_crc = *crc;
- if ((width < 8) && (NULL == _crc_table)) {
- p_crc = (uint32_t)(p_crc << (8 - width));
- }
- // Optimized algorithm for 32BitANSI does not need additional reflect_remainder
- if ((TABLE == _mode) && (POLY_32BIT_REV_ANSI == polynomial)) {
- *crc = (p_crc ^ _final_xor) & get_crc_mask();
- } else {
- *crc = (reflect_remainder(p_crc) ^ _final_xor) & get_crc_mask();
- }
- unlock();
- return 0;
- }
-
- /** Get the current CRC polynomial.
- *
- * @return Polynomial value
- */
- uint32_t get_polynomial(void) const
- {
- return polynomial;
- }
-
- /** Get the current CRC width
- *
- * @return CRC width
- */
- uint8_t get_width(void) const
- {
- return width;
- }
-
-#if !defined(DOXYGEN_ONLY)
-private:
- uint32_t _initial_value;
- uint32_t _final_xor;
- bool _reflect_data;
- bool _reflect_remainder;
- uint32_t *_crc_table;
- CrcMode _mode;
-
- /** Acquire exclusive access to CRC hardware/software.
- */
- void lock()
- {
-#if DEVICE_CRC
- if (_mode == HARDWARE) {
- mbed_crc_mutex->lock();
- }
-#endif
- }
-
- /** Release exclusive access to CRC hardware/software.
- */
- virtual void unlock()
- {
-#if DEVICE_CRC
- if (_mode == HARDWARE) {
- mbed_crc_mutex->unlock();
- }
-#endif
- }
-
- /** Get the current CRC data size.
- *
- * @return CRC data size in bytes
- */
- uint8_t get_data_size(void) const
- {
- return (width <= 8 ? 1 : (width <= 16 ? 2 : 4));
- }
-
- /** Get the top bit of current CRC.
- *
- * @return Top bit is set high for respective data width of current CRC
- * Top bit for CRC width less then 8 bits will be set as 8th bit.
- */
- uint32_t get_top_bit(void) const
- {
- return (width < 8 ? (1u << 7) : (uint32_t)(1ul << (width - 1)));
- }
-
- /** Get the CRC data mask.
- *
- * @return CRC data mask is generated based on current CRC width
- */
- uint32_t get_crc_mask(void) const
- {
- return (width < 8 ? ((1u << 8) - 1) : (uint32_t)((uint64_t)(1ull << width) - 1));
- }
-
- /** Final value of CRC is reflected.
- *
- * @param data final crc value, which should be reflected
- * @return Reflected CRC value
- */
- uint32_t reflect_remainder(uint32_t data) const
- {
- if (_reflect_remainder) {
- uint32_t reflection = 0x0;
- uint8_t const nBits = (width < 8 ? 8 : width);
-
- for (uint8_t bit = 0; bit < nBits; ++bit) {
- if (data & 0x01) {
- reflection |= (1 << ((nBits - 1) - bit));
- }
- data = (data >> 1);
- }
- return (reflection);
- } else {
- return data;
- }
- }
-
- /** Data bytes are reflected.
- *
- * @param data value to be reflected
- * @return Reflected data value
- */
- uint32_t reflect_bytes(uint32_t data) const
- {
- if (_reflect_data) {
- uint32_t reflection = 0x0;
-
- for (uint8_t bit = 0; bit < 8; ++bit) {
- if (data & 0x01) {
- reflection |= (1 << (7 - bit));
- }
- data = (data >> 1);
- }
- return (reflection);
- } else {
- return data;
- }
- }
-
- /** Bitwise CRC computation.
- *
- * @param buffer data buffer
- * @param size size of the data
- * @param crc CRC value is filled in, but the value is not the final
- * @return 0 on success or a negative error code on failure
- */
- int32_t bitwise_compute_partial(const void *buffer, crc_data_size_t size, uint32_t *crc) const
- {
- MBED_ASSERT(crc != NULL);
-
- const uint8_t *data = static_cast<const uint8_t *>(buffer);
- uint32_t p_crc = *crc;
-
- if (width < 8) {
- uint8_t data_byte;
- for (crc_data_size_t byte = 0; byte < size; byte++) {
- data_byte = reflect_bytes(data[byte]);
- for (uint8_t bit = 8; bit > 0; --bit) {
- p_crc <<= 1;
- if ((data_byte ^ p_crc) & get_top_bit()) {
- p_crc ^= polynomial;
- }
- data_byte <<= 1;
- }
- }
- } else {
- for (crc_data_size_t byte = 0; byte < size; byte++) {
- p_crc ^= (reflect_bytes(data[byte]) << (width - 8));
-
- // Perform modulo-2 division, a bit at a time
- for (uint8_t bit = 8; bit > 0; --bit) {
- if (p_crc & get_top_bit()) {
- p_crc = (p_crc << 1) ^ polynomial;
- } else {
- p_crc = (p_crc << 1);
- }
- }
- }
- }
- *crc = p_crc & get_crc_mask();
- return 0;
- }
-
- /** CRC computation using ROM tables.
- *
- * @param buffer data buffer
- * @param size size of the data
- * @param crc CRC value is filled in, but the value is not the final
- * @return 0 on success or a negative error code on failure
- */
- int32_t table_compute_partial(const void *buffer, crc_data_size_t size, uint32_t *crc) const
- {
- MBED_ASSERT(crc != NULL);
-
- const uint8_t *data = static_cast<const uint8_t *>(buffer);
- uint32_t p_crc = *crc;
- uint8_t data_byte = 0;
-
- if (width <= 8) {
- uint8_t *crc_table = (uint8_t *)_crc_table;
- for (crc_data_size_t byte = 0; byte < size; byte++) {
- data_byte = reflect_bytes(data[byte]) ^ p_crc;
- p_crc = crc_table[data_byte];
- }
- } else if (width <= 16) {
- uint16_t *crc_table = (uint16_t *)_crc_table;
- for (crc_data_size_t byte = 0; byte < size; byte++) {
- data_byte = reflect_bytes(data[byte]) ^ (p_crc >> (width - 8));
- p_crc = crc_table[data_byte] ^ (p_crc << 8);
- }
- } else {
- uint32_t *crc_table = (uint32_t *)_crc_table;
- if (POLY_32BIT_REV_ANSI == polynomial) {
- for (crc_data_size_t i = 0; i < size; i++) {
- p_crc = (p_crc >> 4) ^ crc_table[(p_crc ^ (data[i] >> 0)) & 0xf];
- p_crc = (p_crc >> 4) ^ crc_table[(p_crc ^ (data[i] >> 4)) & 0xf];
- }
- } else {
- for (crc_data_size_t byte = 0; byte < size; byte++) {
- data_byte = reflect_bytes(data[byte]) ^ (p_crc >> (width - 8));
- p_crc = crc_table[data_byte] ^ (p_crc << 8);
- }
- }
- }
- *crc = p_crc & get_crc_mask();
- return 0;
- }
-
- /** Constructor init called from all specialized cases of constructor.
- * Note: All constructor common code should be in this function.
- */
- void mbed_crc_ctor(void)
- {
- MBED_STATIC_ASSERT(width <= 32, "Max 32-bit CRC supported");
-
-#if DEVICE_CRC
- if (POLY_32BIT_REV_ANSI == polynomial) {
- _crc_table = (uint32_t *)Table_CRC_32bit_Rev_ANSI;
- _mode = TABLE;
- return;
- }
- crc_mbed_config_t config;
- config.polynomial = polynomial;
- config.width = width;
- config.initial_xor = _initial_value;
- config.final_xor = _final_xor;
- config.reflect_in = _reflect_data;
- config.reflect_out = _reflect_remainder;
-
- if (hal_crc_is_supported(&config)) {
- _mode = HARDWARE;
- return;
- }
-#endif
-
- switch (polynomial) {
- case POLY_32BIT_ANSI:
- _crc_table = (uint32_t *)Table_CRC_32bit_ANSI;
- break;
- case POLY_32BIT_REV_ANSI:
- _crc_table = (uint32_t *)Table_CRC_32bit_Rev_ANSI;
- break;
- case POLY_8BIT_CCITT:
- _crc_table = (uint32_t *)Table_CRC_8bit_CCITT;
- break;
- case POLY_7BIT_SD:
- _crc_table = (uint32_t *)Table_CRC_7Bit_SD;
- break;
- case POLY_16BIT_CCITT:
- _crc_table = (uint32_t *)Table_CRC_16bit_CCITT;
- break;
- case POLY_16BIT_IBM:
- _crc_table = (uint32_t *)Table_CRC_16bit_IBM;
- break;
- default:
- _crc_table = NULL;
- break;
- }
- _mode = (_crc_table != NULL) ? TABLE : BITWISE;
- }
-#endif
-};
-
-#if defined ( __CC_ARM )
-#elif defined ( __GNUC__ )
-#pragma GCC diagnostic pop
-#elif defined (__ICCARM__)
-#endif
-
-/** @}*/
-} // namespace mbed
-
-#endif