esp-idf/components/driver/sdspi_crc.c

// Copyright 2015-2017 Espressif Systems (Shanghai) PTE LTD
//
// 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 <stdint.h>
#include "sdspi_crc.h"
#include "sdkconfig.h"
#if CONFIG_IDF_TARGET_ESP32
#include "esp32/rom/crc.h"
#elif CONFIG_IDF_TARGET_ESP32S2
// CRC16 not implemented in the ROM, will implement it below
#else
#error CRC16 not implemented yet! Choose from ROM or the impl below
#endif

static const uint8_t crc7_table[256] =
{
	0x00,  0x09,  0x12,  0x1b,  0x24,  0x2d,  0x36,  0x3f,  0x48,  0x41,  0x5a,  0x53,  0x6c,  0x65,  0x7e,  0x77,
	0x19,  0x10,  0x0b,  0x02,  0x3d,  0x34,  0x2f,  0x26,  0x51,  0x58,  0x43,  0x4a,  0x75,  0x7c,  0x67,  0x6e,
	0x32,  0x3b,  0x20,  0x29,  0x16,  0x1f,  0x04,  0x0d,  0x7a,  0x73,  0x68,  0x61,  0x5e,  0x57,  0x4c,  0x45,
	0x2b,  0x22,  0x39,  0x30,  0x0f,  0x06,  0x1d,  0x14,  0x63,  0x6a,  0x71,  0x78,  0x47,  0x4e,  0x55,  0x5c,
	0x64,  0x6d,  0x76,  0x7f,  0x40,  0x49,  0x52,  0x5b,  0x2c,  0x25,  0x3e,  0x37,  0x08,  0x01,  0x1a,  0x13,
	0x7d,  0x74,  0x6f,  0x66,  0x59,  0x50,  0x4b,  0x42,  0x35,  0x3c,  0x27,  0x2e,  0x11,  0x18,  0x03,  0x0a,
	0x56,  0x5f,  0x44,  0x4d,  0x72,  0x7b,  0x60,  0x69,  0x1e,  0x17,  0x0c,  0x05,  0x3a,  0x33,  0x28,  0x21,
	0x4f,  0x46,  0x5d,  0x54,  0x6b,  0x62,  0x79,  0x70,  0x07,  0x0e,  0x15,  0x1c,  0x23,  0x2a,  0x31,  0x38,
	0x41,  0x48,  0x53,  0x5a,  0x65,  0x6c,  0x77,  0x7e,  0x09,  0x00,  0x1b,  0x12,  0x2d,  0x24,  0x3f,  0x36,
	0x58,  0x51,  0x4a,  0x43,  0x7c,  0x75,  0x6e,  0x67,  0x10,  0x19,  0x02,  0x0b,  0x34,  0x3d,  0x26,  0x2f,
	0x73,  0x7a,  0x61,  0x68,  0x57,  0x5e,  0x45,  0x4c,  0x3b,  0x32,  0x29,  0x20,  0x1f,  0x16,  0x0d,  0x04,
	0x6a,  0x63,  0x78,  0x71,  0x4e,  0x47,  0x5c,  0x55,  0x22,  0x2b,  0x30,  0x39,  0x06,  0x0f,  0x14,  0x1d,
	0x25,  0x2c,  0x37,  0x3e,  0x01,  0x08,  0x13,  0x1a,  0x6d,  0x64,  0x7f,  0x76,  0x49,  0x40,  0x5b,  0x52,
	0x3c,  0x35,  0x2e,  0x27,  0x18,  0x11,  0x0a,  0x03,  0x74,  0x7d,  0x66,  0x6f,  0x50,  0x59,  0x42,  0x4b,
	0x17,  0x1e,  0x05,  0x0c,  0x33,  0x3a,  0x21,  0x28,  0x5f,  0x56,  0x4d,  0x44,  0x7b,  0x72,  0x69,  0x60,
	0x0e,  0x07,  0x1c,  0x15,  0x2a,  0x23,  0x38,  0x31,  0x46,  0x4f,  0x54,  0x5d,  0x62,  0x6b,  0x70,  0x79,
};

// returns the CRC-7 for a message of "length" bytes
uint8_t sdspi_crc7(const uint8_t *data, size_t size)
{
    uint8_t result = 0;
    for (size_t i = 0; i < size; ++i) {
        result = crc7_table[(result << 1) ^ data[i]];
    }
    return result;
}

#if !ESP_ROM_HAS_CRC16BE
static uint16_t crc16_be_table[256] = {
	0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, 0x8108, 0x9129,0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
	0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, 0x9339, 0x8318,0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
	0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485, 0xa56a, 0xb54b,0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
	0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4, 0xb75b, 0xa77a,0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
	0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823, 0xc9cc, 0xd9ed,0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
	0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, 0xdbfd, 0xcbdc,0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
	0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, 0xedae, 0xfd8f,0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
	0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70, 0xff9f, 0xefbe,0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
	0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f, 0x1080, 0x00a1,0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
	0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, 0x02b1, 0x1290,0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
	0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, 0x34e2, 0x24c3,0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
	0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c, 0x26d3, 0x36f2,0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
	0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab, 0x5844, 0x4865,0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
	0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a, 0x4a75, 0x5a54,0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
	0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, 0x7c26, 0x6c07,0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
	0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, 0x6e17, 0x7e36,0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
};

uint16_t crc16_be(uint16_t crc, uint8_t const * buf,uint32_t len)
{
	uint32_t i;
	crc = ~crc;
	for(i=0;i<len;i++){
		crc = crc16_be_table[(crc>>8)^buf[i]]^(crc<<8);
	}
	return ~crc;
}
#endif //!ESP_ROM_HAS_CRC16BE

/// Return CRC16 of data, in the on-the-wire format used by SD protocol
uint16_t sdspi_crc16(const uint8_t* data, size_t size)
{
    return __builtin_bswap16(crc16_be(UINT16_MAX, data, size) ^ UINT16_MAX);
}