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774 lines
16 KiB
C
774 lines
16 KiB
C
/*
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Copyright 2007, Freie Universitaet Berlin. All rights reserved.
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These sources were developed at the Freie Universität Berlin, Computer
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Systems and Telematics group.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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- Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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- Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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- Neither the name of Freie Universitaet Berlin (FUB) nor the names of its
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contributors may be used to endorse or promote products derived from
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this software without specific prior written permission.
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This software is provided by FUB and the contributors on an "as is"
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basis, without any representations or warranties of any kind, express
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or implied including, but not limited to, representations or
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warranties of non-infringement, merchantability or fitness for a
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particular purpose. In no event shall FUB or contributors be liable
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for any direct, indirect, incidental, special, exemplary, or
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consequential damages (including, but not limited to, procurement of
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substitute goods or services; loss of use, data, or profits; or
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business interruption) however caused and on any theory of liability,
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whether in contract, strict liability, or tort (including negligence
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or otherwise) arising in any way out of the use of this software, even
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if advised of the possibility of such damage.
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This implementation was developed by the CST group at the FUB.
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For documentation and questions please use the web site
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http://scatterweb.mi.fu-berlin.de and the mailinglist
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scatterweb@lists.spline.inf.fu-berlin.de (subscription via the Website).
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Berlin, 2007
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*/
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/**
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* @file ScatterWeb.Sd.c
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* @ingroup libsd
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* @brief MMC-/SD-Card library
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*
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* @author Michael Baar <baar@inf.fu-berlin.de>
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* @version $Revision: 1.3 $
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*
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* $Id: sd.c,v 1.3 2008/03/28 23:03:05 nvt-se Exp $
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*
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* Initialisation and basic functions for read and write access
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*/
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#include "sd_internals.h"
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#include "sd.h"
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volatile sd_state_t sd_state;
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/******************************************************************************
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* @name Initialization and configuration
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* @{
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*/
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void
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sd_init(void)
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{
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// depending on the system global variables may not get initialised on startup
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memset((void *)&sd_state, 0, sizeof (sd_state));
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// initialize io ports
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sd_init_platform();
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}
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enum sd_init_ret
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sd_init_card(sd_cache_t * pCache)
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{
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enum sd_init_ret ret = SD_INIT_SUCCESS;
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struct sd_csd csd;
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uint16_t ccc = 0;
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int resetcnt;
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struct sd_response_r3 r3;
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if (!sd_detected()) {
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return SD_INIT_NOCARD;
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}
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if (sd_state.Flags & SD_INITIALIZED) {
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return SD_INIT_SUCCESS;
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}
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// Wait for UART and switch to SPI mode
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if (!uart_lock_wait(UART_MODE_SPI)) {
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return SD_INIT_FAILED;
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}
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// reset card
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resetcnt = _sd_reset(&r3);
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if (resetcnt >= SD_RESET_RETRY_COUNT) {
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ret = SD_INIT_FAILED;
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goto sd_init_card_fail;
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}
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// Test for hardware compatibility
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if ((r3.ocr & SD_V_MASK) != SD_V_MASK) {
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ret = SD_INIT_NOTSUPP;
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goto sd_init_card_fail;
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}
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// Test for software compatibility
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if (!_sd_read_register(&csd, SD_CMD_SEND_CSD, sizeof (struct sd_csd))) {
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ret = SD_INIT_FAILED;
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goto sd_init_card_fail;
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}
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ccc = SD_CSD_CCC(csd);
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if ((ccc & SD_DEFAULT_MINCCC) != SD_DEFAULT_MINCCC) {
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ret = SD_INIT_NOTSUPP;
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goto sd_init_card_fail;
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}
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sd_init_card_fail:
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sdspi_unselect();
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uart_unlock(UART_MODE_SPI);
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#ifdef LOG_VERBOSE
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LOG_VERBOSE("(sd_init) result:%u, resetcnt:%i OCR:%.8lx, CCC:%.4x",
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ret, resetcnt, r3.ocr, ccc);
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#endif
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if (ret != SD_INIT_SUCCESS) {
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return ret;
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}
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// state
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sd_state.MinBlockLen_bit = 9;
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sd_state.MaxBlockLen_bit = SD_CSD_READ_BL_LEN(csd);
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sd_state.Flags = SD_INITIALIZED;
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if (SD_CSD_READ_PARTIAL(csd)) {
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sd_state.MinBlockLen_bit = 0;
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sd_state.Flags |= SD_READ_PARTIAL;
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}
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if (SD_CSD_WRITE_PARTIAL(csd)) {
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sd_state.Flags |= SD_WRITE_PARTIAL;
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}
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sd_state.BlockLen_bit = 9;
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sd_state.BlockLen = 1 << 9;
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#if SD_CACHE
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if (pCache == NULL) {
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return SD_INIT_NOTSUPP;
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}
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sd_state.Cache = pCache;
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_sd_cache_init();
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#endif
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return ret;
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}
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void
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sd_flush(void)
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{
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if (uart_lock(UART_MODE_SPI)) {
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#if SD_WRITE && SD_CACHE
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_sd_cache_flush();
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#endif
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#if SD_WRITE && SPI_DMA_WRITE
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sd_write_flush();
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#endif
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uart_unlock(UART_MODE_SPI);
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}
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}
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void
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sd_close(void)
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{
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sd_flush();
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// reset state
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memset((void *)&sd_state, 0, sizeof (sd_state));
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}
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uint8_t
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sd_set_blocklength(const uint8_t blocklength_bit)
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{
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uint8_t ret;
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uint8_t arg[4];
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// test if already set
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if (blocklength_bit == sd_state.BlockLen_bit) {
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return sd_state.BlockLen_bit;
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}
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// Wait for UART and switch to SPI mode
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if (!uart_lock_wait(UART_MODE_SPI)) {
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return sd_state.BlockLen_bit;
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}
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((uint16_t *) arg)[1] = 0;
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((uint16_t *) arg)[0] = 1 << blocklength_bit;
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// set blocklength command
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if (_sd_send_cmd(SD_CMD_SET_BLOCKLENGTH, SD_RESPONSE_SIZE_R1, arg, NULL)) {
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sd_state.BlockLen_bit = blocklength_bit;
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sd_state.BlockLen = ((uint16_t *) arg)[0];
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ret = blocklength_bit;
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} else {
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ret = SD_BLOCKLENGTH_INVALID;
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}
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// unlock uart
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uart_unlock(UART_MODE_SPI);
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return ret;
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}
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//@}
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///////////////////////////////////////////////////////////////////////////////
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// Public functions, Reading
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///////////////////////////////////////////////////////////////////////////////
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uint16_t
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sd_AlignAddress(uint32_t * pAddress)
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{
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uint16_t blMask = sd_state.BlockLen - 1;
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uint16_t *lw = (uint16_t *) pAddress;
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uint16_t offset = *lw & blMask;
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*lw &= ~blMask;
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return offset;
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}
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uint16_t
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sd_read_block(void (*const pBuffer), const uint32_t address)
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{
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if (!_sd_read_start(SD_CMD_READ_SINGLE_BLOCK, address)) {
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return FALSE;
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}
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sdspi_read(pBuffer, sd_state.BlockLen, TRUE);
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// receive CRC16 and finish
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_sd_read_stop(2);
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return sd_state.BlockLen;
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}
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#if SD_READ_BYTE
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bool
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sd_read_byte(void *pBuffer, const uint32_t address)
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{
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if (sd_set_blocklength(0) == 0) {
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return sd_read_block(pBuffer, address);
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} else {
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uint32_t blAdr = address;
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uint16_t offset; // bytes from aligned address to start of first byte to keep
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// align
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offset = sd_AlignAddress(&blAdr);
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// start
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if (!_sd_read_start(SD_CMD_READ_SINGLE_BLOCK, address)) {
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return FALSE;
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}
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// read
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Spi_read(pBuffer, offset + 1, FALSE);
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// done
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_sd_read_stop(sd_state.BlockLen - offset - 1);
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}
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return TRUE;
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}
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#endif
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#if SD_READ_ANY && !SD_CACHE
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unsigned int
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sd_read(void *pBuffer, unsigned long address, unsigned int size)
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{
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unsigned char *p; // pointer to current pos in receive buffer
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unsigned int offset; // bytes from aligned address to start of first byte to keep
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unsigned int read_count; // num bytes to read in one iteration
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bool dump_flag; // number of bytes to dump in last iteration
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unsigned int num_bytes_read; // number of bytes read into receive buffer
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unsigned char ret;
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//
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// parameter processing
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//
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if (size == 0) {
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return FALSE;
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}
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// align to block
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offset = sd_AlignAddress(&address);
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if ((offset == 0) && (sd_state.BlockLen == size)) {
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// best case: perfectly block aligned, no chunking
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// -> do shortcut
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return sd_read_block(pBuffer, address);
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}
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// calculate first block
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if (size > sd_state.BlockLen) {
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read_count = sd_state.BlockLen;
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} else {
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read_count = size;
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}
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//
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// Data transfer
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//
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// request data transfer
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ret = _sd_read_start(SD_CMD_READ_SINGLE_BLOCK, address);
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RETF(ret);
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// run to offset
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if (offset) {
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sdspi_read(pBuffer, offset, FALSE); // dump till offset
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dump_flag = ((read_count + offset) < sd_state.BlockLen);
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if (!dump_flag) {
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read_count = sd_state.BlockLen - offset; // max bytes to read from first block
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}
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} else {
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dump_flag = (read_count < sd_state.BlockLen);
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}
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//
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// block read loop
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//
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num_bytes_read = 0;
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p = pBuffer;
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do {
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// whole block will be processed
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size -= read_count; // global counter
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// read to receive buffer
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sdspi_read(p, read_count, TRUE);
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p += read_count; // increment buffer pointer
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num_bytes_read += read_count;
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// finish block
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if (dump_flag) {
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// cancel remaining bytes (last iteration)
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_sd_read_stop(sd_state.BlockLen - read_count - offset);
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break;
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// unselect is included in send_cmd
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} else {
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sdspi_idle(2); // receive CRC16
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if (size != 0) {
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// address calculation for next block
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offset = 0;
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address += sd_state.BlockLen;
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if (size > sd_state.BlockLen) {
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read_count = sd_state.BlockLen;
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dump_flag = FALSE;
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} else {
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read_count = size;
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dump_flag = TRUE;
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}
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sdspi_unselect();
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ret = _sd_read_start(SD_CMD_READ_SINGLE_BLOCK, address);
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RETF(ret);
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} else {
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// finished
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_sd_read_stop(0);
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break;
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}
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}
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} while (1);
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return num_bytes_read;
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}
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#endif // SD_READ_ANY
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///////////////////////////////////////////////////////////////////////////////
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// Public functions, Writing
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///////////////////////////////////////////////////////////////////////////////
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#if SD_WRITE
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enum sd_write_ret
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_sd_write_finish(void)
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{
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uint16_t r2;
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uint8_t ret;
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enum sd_write_ret result = SD_WRITE_STORE_ERR;
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uint16_t i;
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#if SPI_DMA_WRITE
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sdspi_dma_wait();
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sdspi_dma_lock = FALSE;
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#endif
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// dummy crc
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sdspi_idle(2);
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// receive data response (ZZS___ 3 bits crc response)
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for (i = 0; i < SD_TIMEOUT_NCR; i++) {
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ret = sdspi_rx();
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if ((ret > 0) && (ret < 0xFF)) {
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while (ret & 0x80) {
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ret <<= 1;
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}
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ret = ((ret & 0x70) == 0x20);
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break;
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}
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}
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// wait for data to be written
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_sd_wait_standby(NULL);
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sdspi_unselect();
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if (ret) {
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// data transfer to sd card buffer was successful
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// query for result of actual write operation
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ret = _sd_send_cmd(SD_CMD_SEND_STATUS, SD_RESPONSE_SIZE_R2, NULL, &r2);
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if (ret && (r2 == 0)) {
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result = SD_WRITE_SUCCESS;
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}
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} else {
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// data transfer to sd card buffer failed
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}
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// unlock uart (locked from every write operation)
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uart_unlock(UART_MODE_SPI);
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return result;
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}
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enum sd_write_ret
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sd_write_flush(void)
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{
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#if SPI_DMA_WRITE
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if (!sdspi_dma_lock) {
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return SD_WRITE_DMA_ERR;
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} else {
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return _sd_write_finish();
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}
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#else
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return SD_WRITE_SUCCESS;
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#endif
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}
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enum sd_write_ret
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_sd_write_block(const uint32_t * pAddress, const void *pBuffer, int increment)
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{
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uint8_t r1, ret;
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// block write-access on write protection
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if (sd_protected()) {
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return SD_WRITE_PROTECTED_ERR;
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}
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// acquire uart
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if (!uart_lock_wait(UART_MODE_SPI)) {
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return SD_WRITE_INTERFACE_ERR;
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}
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// start write
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SD_LED_WRITE_ON;
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r1 = 0;
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ret = _sd_send_cmd(SD_CMD_WRITE_SINGLE_BLOCK, SD_RESPONSE_SIZE_R1,
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pAddress, &r1);
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if (!ret | r1) {
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uart_unlock(UART_MODE_SPI);
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printf("r1 = %u\n", r1);
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SD_LED_WRITE_OFF;
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return SD_WRITE_COMMAND_ERR;
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}
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// write data
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sdspi_select();
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sdspi_tx(0xFF);
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sdspi_tx(SD_TOKEN_WRITE);
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sdspi_write(pBuffer, sd_state.BlockLen, increment);
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SD_LED_WRITE_OFF;
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// finish write
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#if SPI_DMA_WRITE
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sdspi_dma_lock = TRUE;
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return SD_WRITE_SUCCESS;
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#else
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return _sd_write_finish();
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#endif
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}
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enum sd_write_ret
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sd_set_block(const uint32_t address, const char (*const pChar))
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{
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return _sd_write_block(&address, pChar, FALSE);
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}
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enum sd_write_ret
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sd_write_block(const uint32_t address, void const (*const pBuffer))
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{
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return _sd_write_block(&address, pBuffer, TRUE);
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}
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#endif
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///////////////////////////////////////////////////////////////////////////////
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// Supporting functions
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///////////////////////////////////////////////////////////////////////////////
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/**
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* @brief Reads operating condition from SD or MMC card.
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* \internal
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* \Note Should allow to find out the card type on first run if needed.
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*/
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inline bool _sd_get_op_cond(struct sd_response_r1 * pResponse)
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{
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bool ret;
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// SD style
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ret = _sd_send_cmd(SD_CMD_APP_SECIFIC_CMD, SD_RESPONSE_SIZE_R1, NULL,
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pResponse);
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if (ret) {
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uint32_t arg = SD_V_MASK;
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ret = _sd_send_cmd(SD_ACMD_SEND_OP_COND, SD_RESPONSE_SIZE_R1, &arg,
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pResponse);
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} else {
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// MMC style init
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ret = _sd_send_cmd(SD_CMD_SEND_OP_COND, SD_RESPONSE_SIZE_R1, NULL,
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pResponse);
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if (*((uint8_t *) pResponse) & SD_R1_ERROR_MASK) {
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ret = FALSE;
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}
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}
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return ret;
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}
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/**
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* @brief Wait for the card to enter standby state
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* \internal
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*/
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bool
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_sd_wait_standby(struct sd_response_r3 * pOpCond)
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{
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bool ret;
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int i = SD_TIMEOUT_IDLE;
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struct sd_response_r3 opCond;
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struct sd_response_r3 *pR3 = pOpCond;
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if (pR3 == NULL) {
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pR3 = &opCond;
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}
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sdspi_wait_token(0xFF, 0xFF, 0xFF, SD_TIMEOUT_NCR);
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do {
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ret = _sd_get_op_cond((struct sd_response_r1 *)pR3);
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if (ret && (pR3->r1.in_idle_state == 0)) {
|
|
ret = _sd_send_cmd(SD_CMD_READ_OCR, SD_RESPONSE_SIZE_R3, NULL, pR3);
|
|
if (ret && !SD_OCR_BUSY(pR3->ocr)) {
|
|
return TRUE;
|
|
}
|
|
}
|
|
i--;
|
|
} while (i);
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
/**
|
|
* @brief Resets the card and (hopefully) returns with the card in standby state
|
|
* \internal
|
|
*/
|
|
int
|
|
_sd_reset(struct sd_response_r3 *pOpCond)
|
|
{
|
|
int i;
|
|
bool ret;
|
|
struct sd_response_r1 r1;
|
|
|
|
for (i = 0; i < SD_RESET_RETRY_COUNT; i++) {
|
|
ret = _sd_send_cmd(SD_CMD_GO_IDLE_STATE, SD_RESPONSE_SIZE_R1, NULL, &r1);
|
|
if (ret == 0 || r1.illegal_cmd) {
|
|
_sd_send_cmd(SD_CMD_STOP_TRANSMISSION, SD_RESPONSE_SIZE_R1, NULL, &r1);
|
|
} else {
|
|
ret = _sd_wait_standby(pOpCond);
|
|
if (ret) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
/**
|
|
* @brief Used to send all kinds of commands to the card and return the response.
|
|
* \internal
|
|
*/
|
|
bool
|
|
_sd_send_cmd(const uint8_t command,
|
|
const int response_size,
|
|
const void *pArg, void (*const pResponse))
|
|
{
|
|
uint8_t cmd[6] = {
|
|
0x40, 0, 0, 0, 0, 0x95
|
|
};
|
|
uint8_t data; // rx buffer
|
|
int i; // loop counter
|
|
|
|
#if SD_WRITE && SPI_DMA_WRITE
|
|
sd_write_flush();
|
|
#endif
|
|
|
|
sdspi_select();
|
|
cmd[0] |= command;
|
|
if (pArg != NULL) {
|
|
cmd[1] = ((uint8_t *) pArg)[3];
|
|
cmd[2] = ((uint8_t *) pArg)[2];
|
|
cmd[3] = ((uint8_t *) pArg)[1];
|
|
cmd[4] = ((uint8_t *) pArg)[0];
|
|
}
|
|
|
|
sdspi_write(cmd, 6, 1);
|
|
|
|
// wait for start bit
|
|
i = SD_TIMEOUT_NCR;
|
|
do {
|
|
data = sdspi_rx();
|
|
if ((data & 0x80) == 0) {
|
|
goto _sd_send_cmd_response;
|
|
}
|
|
} while (i);
|
|
|
|
goto sd_send_cmd_fail;
|
|
|
|
_sd_send_cmd_response:
|
|
// start bit received, read response with size i
|
|
i = response_size - 1;
|
|
if (pResponse != NULL) {
|
|
// copy response to response buffer
|
|
do {
|
|
((uint8_t *) pResponse)[i] = data;
|
|
if (i == 0) {
|
|
break;
|
|
}
|
|
|
|
data = sdspi_rx();
|
|
i--;
|
|
} while (1);
|
|
} else {
|
|
// receive and ignore response
|
|
sdspi_read(&data, i, 0);
|
|
}
|
|
|
|
// done successfully
|
|
sdspi_unselect();
|
|
|
|
return TRUE;
|
|
|
|
sd_send_cmd_fail:
|
|
// failed
|
|
//sdspi_unselect();
|
|
return FALSE;
|
|
|
|
}
|
|
|
|
/**
|
|
* @brief Read Card Register
|
|
* \internal
|
|
*/
|
|
uint16_t
|
|
_sd_read_register(void *pBuffer, uint8_t cmd, uint16_t size)
|
|
{
|
|
if (!_sd_read_start(cmd, 0)) {
|
|
return FALSE;
|
|
}
|
|
|
|
sdspi_read(pBuffer, size, TRUE);
|
|
_sd_read_stop(2);
|
|
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* @brief Begin block read operation
|
|
* \internal
|
|
*/
|
|
bool
|
|
_sd_read_start(uint8_t cmd, uint32_t address)
|
|
{
|
|
uint8_t r1;
|
|
uint8_t ret;
|
|
uint16_t i;
|
|
|
|
// aquire uart
|
|
if (!uart_lock_wait(UART_MODE_SPI)) {
|
|
return FALSE;
|
|
}
|
|
|
|
ret = _sd_send_cmd(cmd, SD_RESPONSE_SIZE_R1, &address, &r1);
|
|
if (!ret || r1) {
|
|
goto _sd_read_start_fail;
|
|
}
|
|
|
|
// Wait for start bit (0)
|
|
sdspi_select();
|
|
|
|
i = sdspi_wait_token(0xFF, 0xFF, SD_TOKEN_READ, SD_TIMEOUT_READ);
|
|
|
|
if (i < SD_TIMEOUT_READ) {
|
|
// token received, data bytes follow
|
|
SD_LED_READ_ON;
|
|
|
|
/*
|
|
Following code handles error tokens. Since these are currently not used in the
|
|
application they can just be ignored. Anyway this is still useful when debugging.
|
|
else if( (data != 0) && (data & SD_DATA_ERROR_TOKEN_MASK) == data ) {
|
|
// data error token
|
|
sdspi_rx();
|
|
break;
|
|
} */
|
|
return TRUE;
|
|
} else {
|
|
// error or timeout
|
|
}
|
|
|
|
_sd_read_start_fail:
|
|
sdspi_unselect();
|
|
uart_unlock(UART_MODE_SPI);
|
|
return FALSE;
|
|
}
|
|
|
|
/**
|
|
* @brief Finished with reading, stop transfer
|
|
* \internal
|
|
*/
|
|
void
|
|
_sd_read_stop(uint16_t count)
|
|
{
|
|
// finish block + crc
|
|
if (count) {
|
|
uint8_t dump;
|
|
|
|
sdspi_read(&dump, count + 2, FALSE);
|
|
sdspi_unselect();
|
|
}
|
|
|
|
SD_LED_READ_OFF;
|
|
|
|
// wait for switch to standby mode
|
|
if (!_sd_wait_standby(NULL)) {
|
|
_sd_reset(NULL);
|
|
}
|
|
|
|
// unlock uart (locked from _sd_read_start)
|
|
uart_unlock(UART_MODE_SPI);
|
|
}
|