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SDCard.c
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SDCard.c
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/*****************************************************************************
* *
* DFU/SD/SDHC Bootloader for LPC17xx *
* *
* by Triffid Hunter *
* *
* *
* This firmware is Copyright (C) 2009-2010 Michael Moon aka Triffid_Hunter *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the Free Software *
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA *
* *
*****************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include "SDCard.h"
#include "gpio.h"
#include "config.h"
//static const uint8_t OXFF = 0xFF;
//#define debug
int SDCard__cmd(int cmd, int arg);
int SDCard__cmdx(int cmd, int arg);
int SDCard__cmd8(void);
int SDCard__cmd58(uint32_t *);
int SDCard_initialise_card(void);
int SDCard_initialise_card_v1(void);
int SDCard_initialise_card_v2(void);
int SDCard__read(uint8_t *buffer, int length);
int SDCard__write(const uint8_t *buffer, int length);
// int start_multi_write(uint32_t start_block, uint32_t n_blocks);
// int validate_buffer(uint8_t *, int);
// int end_multi_write(void);
// int start_multi_read(uint32_t start_block, uint32_t n_blocks);
// int validate_buffer(uint8_t *, int);
// int check_buffer(uint8_t *, int);
// int end_multi_read(void);
uint32_t SDCard__sd_sectors(void);
uint32_t _sectors;
// SPI _spi;
PinName _cs;
int busyflags;
// DMA *write_dma;
// DMA *read_dma;
uint32_t busy_buffers;
int cardtype;
#define SD_COMMAND_TIMEOUT 4096
void SDCard_init(PinName mosi, PinName miso, PinName sclk, PinName cs)
{
SPI_init(mosi, miso, sclk);
GPIO_init(cs);
GPIO_output(cs);
GPIO_set(cs);
_cs = cs;
}
#define R1_IDLE_STATE (1 << 0)
#define R1_ERASE_RESET (1 << 1)
#define R1_ILLEGAL_COMMAND (1 << 2)
#define R1_COM_CRC_ERROR (1 << 3)
#define R1_ERASE_SEQUENCE_ERROR (1 << 4)
#define R1_ADDRESS_ERROR (1 << 5)
#define R1_PARAMETER_ERROR (1 << 6)
// Types
// - v1.x Standard Capacity
// - v2.x Standard Capacity
// - v2.x High Capacity
// - Not recognised as an SD Card
#define SDCARD_FAIL 0
#define SDCARD_V1 1
#define SDCARD_V2 2
#define SDCARD_V2HC 3
#define BUSY_FLAG_MULTIREAD 1
#define BUSY_FLAG_MULTIWRITE 2
#define BUSY_FLAG_ENDREAD 4
#define BUSY_FLAG_ENDWRITE 8
#define BUSY_FLAG_WAITNOTBUSY (1<<31)
#define SDCMD_GO_IDLE_STATE 0
#define SDCMD_ALL_SEND_CID 2
#define SDCMD_SEND_RELATIVE_ADDR 3
#define SDCMD_SET_DSR 4
#define SDCMD_SELECT_CARD 7
#define SDCMD_SEND_IF_COND 8
#define SDCMD_SEND_CSD 9
#define SDCMD_SEND_CID 10
#define SDCMD_STOP_TRANSMISSION 12
#define SDCMD_SEND_STATUS 13
#define SDCMD_GO_INACTIVE_STATE 15
#define SDCMD_SET_BLOCKLEN 16
#define SDCMD_READ_SINGLE_BLOCK 17
#define SDCMD_READ_MULTIPLE_BLOCK 18
#define SDCMD_WRITE_BLOCK 24
#define SDCMD_WRITE_MULTIPLE_BLOCK 25
#define SDCMD_PROGRAM_CSD 27
#define SDCMD_SET_WRITE_PROT 28
#define SDCMD_CLR_WRITE_PROT 29
#define SDCMD_SEND_WRITE_PROT 30
#define SDCMD_ERASE_WR_BLOCK_START 32
#define SDCMD_ERASE_WR_BLK_END 33
#define SDCMD_ERASE 38
#define SDCMD_LOCK_UNLOCK 42
#define SDCMD_APP_CMD 55
#define SDCMD_GEN_CMD 56
#define SD_ACMD_SET_BUS_WIDTH 6
#define SD_ACMD_SD_STATUS 13
#define SD_ACMD_SEND_NUM_WR_BLOCKS 22
#define SD_ACMD_SET_WR_BLK_ERASE_COUNT 23
#define SD_ACMD_SD_SEND_OP_COND 41
#define SD_ACMD_SET_CLR_CARD_DETECT 42
#define SD_ACMD_SEND_CSR 51
#define BLOCK2ADDR(block) (((cardtype == SDCARD_V1) || (cardtype == SDCARD_V2))?(block << 9):((cardtype == SDCARD_V2HC)?(block):0))
#define fprintf(...) do {} while (0)
// #define fputs(...) do {} while (0)
int SDCard_initialise_card() {
// Set to 25kHz for initialisation, and clock card with cs = 1
SPI_frequency(25000);
GPIO_set(_cs);
for(int i=0; i<16; i++) {
SPI_write(0xFF);
}
// send CMD0, should return with all zeros except IDLE STATE set (bit 0)
if(SDCard__cmd(SDCMD_GO_IDLE_STATE, 0) != R1_IDLE_STATE) {
#ifdef debug
DBGPRINTF("Could not put SD card in to SPI idle state\n");
#endif
return cardtype = SDCARD_FAIL;
}
// send CMD8 to determine whether it is ver 2.x
int r = SDCard__cmd8();
if(r == R1_IDLE_STATE) {
#ifdef debug
DBGPRINTF("Looks like a SDHC Card\n");
#endif
return SDCard_initialise_card_v2();
} else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
return SDCard_initialise_card_v1();
} else {
#if ENABLED(DEBUG_MESSAGES)
printf(EPFX "Not in idle state after sending CMD8 (not an SD card?)\n");
#endif
return cardtype = SDCARD_FAIL;
}
}
int SDCard_initialise_card_v1() {
for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
SDCard__cmd(SDCMD_APP_CMD, 0);
if(SDCard__cmd(SD_ACMD_SD_SEND_OP_COND, 0) == 0) {
return cardtype = SDCARD_V1;
}
}
DBGPRINTF("Timeout waiting for v1.x card\n");
return SDCARD_FAIL;
}
int SDCard_initialise_card_v2() {
for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
SDCard__cmd(SDCMD_APP_CMD, 0);
if(SDCard__cmd(SD_ACMD_SD_SEND_OP_COND, (1UL<<30)) == 0) {
uint32_t ocr;
SDCard__cmd58(&ocr);
if (ocr & (1UL<<30))
return cardtype = SDCARD_V2HC;
else
return cardtype = SDCARD_V2;
}
}
DBGPRINTF("Timeout waiting for v2.x card\n");
return cardtype = SDCARD_FAIL;
}
int SDCard_disk_initialize()
{
_sectors = 0;
int i = SDCard_initialise_card();
if (i == 0) {
return 1;
}
_sectors = SDCard__sd_sectors();
// Set block length to 512 (CMD16)
if(SDCard__cmd(SDCMD_SET_BLOCKLEN, 512) != 0) {
DBGPRINTF_E("Set 512-byte block timed out\n");
return 1;
}
SPI_frequency(SPI_SPEED);
return 0;
}
int SDCard_disk_write(const uint8_t *buffer, uint32_t block_number)
{
// set write address for single block (CMD24)
if(SDCard__cmd(SDCMD_WRITE_BLOCK, BLOCK2ADDR(block_number)) != 0) {
return 1;
}
// send the data block
SDCard__write(buffer, 512);
return 0;
}
int SDCard_disk_read(uint8_t *buffer, uint32_t block_number)
{
// DBGPRINTF("SD:read type %d: %d(%x) -> %d(%x)\n", cardtype, block_number, block_number, BLOCK2ADDR(block_number), BLOCK2ADDR(block_number));
// set read address for single block (CMD17)
if(SDCard__cmd(SDCMD_READ_SINGLE_BLOCK, BLOCK2ADDR(block_number)) != 0) {
return 1;
}
// receive the data
SDCard__read(buffer, 512);
return 0;
}
int SDCard_disk_erase(uint32_t block_number, int count)
{
return -1;
}
int SDCard_disk_status() { return (_sectors > 0)?0:1; }
int SDCard_disk_sync() {
// TODO: wait for DMA, wait for card not busy
return 0;
}
uint32_t SDCard_disk_sectors() { return _sectors; }
uint64_t SDCard_disk_size() { return ((uint64_t) _sectors) << 9; }
uint32_t SDCard_disk_blocksize() { return (1<<9); }
// int SDCard_disk_canDMA() { return SPI_can_DMA(); }
//
// int SDCard_start_multi_write(uint32_t start_block, uint32_t n_blocks)
// {
// if (!write_dma)
// write_dma = DMA_create();
// if (!write_dma)
// return -1;
//
// if (busyflags)
// return -1;
//
// if (n_blocks == 0)
// return 0;
//
// __disable_irq();
// if (busyflags & ~BUSY_FLAG_WAITNOTBUSY) {
// __enable_irq();
// return -1;
// }
// __enable_irq();
//
// busyflags |= BUSY_FLAG_MULTIWRITE;
//
// // ACMD 23 - SET_WR_BLK_ERASE_COUNT - Set number of blocks to be pre-erased before writing
// _cmd(SDCMD_APP_CMD, 0);
// _cmd(SD_ACMD_SET_WR_BLK_ERASE_COUNT, n_blocks);
//
// // start multi-write
// _cmd(SDCMD_WRITE_MULTIPLE_BLOCK, BLOCK2ADDR(start_block));
//
// return 0;
// }
// int SDCard_validate_buffer(uint8_t *buffer, int bufferlength)
// {
// if (bufferlength != 512)
// return -1;
//
// if (busyflags & BUSY_FLAG_WAITNOTBUSY)
// return -1;
//
// if (busyflags & BUSY_FLAG_MULTIREAD) {
// // disk user has provided an empty buffer for us to fill
// // TODO: set up the DMA transfer, then flick the check flag when it's done
// read_dma->destination(buffer, bufferlength);
// read_dma->start();
// write_dma->start();
// busyflags |= BUSY_FLAG_WAITNOTBUSY;
// return bufferlength;
// }
// else if (busyflags & BUSY_FLAG_MULTIWRITE) {
// // disk user has provided a full buffer for us to empty
// // TODO: continue DMA
// SPI_write(0xFE);
// write_dma->source(buffer, bufferlength);
// write_dma->start();
// busyflags |= BUSY_FLAG_WAITNOTBUSY;
// return bufferlength;
// }
// else if (busyflags & BUSY_FLAG_ENDREAD) {
// _cmd(SDCMD_STOP_TRANSMISSION, 0);
// return 0;
// }
// else if (busyflags & BUSY_FLAG_ENDWRITE) {
// _cmd(SDCMD_STOP_TRANSMISSION, 0);
// return 0;
// }
// return -1;
// }
// int SDCard_end_multi_write()
// {
// busyflags |= BUSY_FLAG_ENDWRITE;
// return 0;
// }
//
// int SDCard_start_multi_read(uint32_t start_block, uint32_t n_blocks)
// {
// if (!read_dma)
// read_dma = DMA_create();
// if (!read_dma)
// return -1;
//
//
// __disable_irq();
// if (busyflags & ~BUSY_FLAG_WAITNOTBUSY) {
// __enable_irq();
// return -1;
// }
// __enable_irq();
//
// busyflags |= BUSY_FLAG_MULTIREAD;
//
// // CMD 18 - READ_MULTIPLE_BLOCK
// _cmd(18, start_block);
//
// return n_blocks;
// }
//
// bool SDCard_check_buffer(uint8_t *buffer, int bufferlength)
// {
// if (busyflags & BUSY_FLAG_MULTIREAD)
// return read_dma->busy();
// if (busyflags & BUSY_FLAG_MULTIWRITE)
// return write_dma->busy();
// return false;
// }
//
// int SDCard_end_multi_read()
// {
// busyflags |= BUSY_FLAG_ENDREAD;
// return 0;
// }
//
// void SDCard_dma_source_event()
// {
// if (busyflags & BUSY_FLAG_MULTIREAD)
// {
// if (read_dma->busy() == false)
// {
// }
// }
// else if (busyflags & BUSY_FLAG_MULTIWRITE)
// {
// if (write_dma->busy() == false)
// {
// // send checksum
// SPI_write(0xFF);
// SPI_write(0xFF);
// busyflags |= BUSY_FLAG_WAITNOTBUSY;
// }
// }
// }
//
// void SDCard_dma_dest_event()
// {
// }
// void SDCard_on_main_loop()
// {
// if (busyflags & BUSY_FLAG_MULTIREAD)
// {
// if (busyflags & BUSY_FLAG_ENDREAD)
// {
//
// }
// }
// if (busyflags & BUSY_FLAG_MULTIWRITE)
// {
// if (busyflags & BUSY_FLAG_ENDWRITE)
// {
// if (SPI_write(0xFF) == 0)
// {
// busyflags &= ~BUSY_FLAG_ENDWRITE;
// }
// }
// }
// }
// PRIVATE FUNCTIONS
int SDCard__cmd(int cmd, int arg) {
// _cs = 0;
GPIO_clear(_cs);
#ifdef debug
DBGPRINTF("SDCMD:%u ", cmd);
#endif
// send a command
SPI_write(0x40 | cmd);
SPI_write(arg >> 24);
SPI_write(arg >> 16);
SPI_write(arg >> 8);
SPI_write(arg >> 0);
SPI_write(0x95);
// wait for the repsonse (response[7] == 0)
for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
int response = SPI_write(0xFF);
if(!(response & 0x80)) {
GPIO_set(_cs);
SPI_write(0xFF);
#ifdef debug
printf(" <%u\n", response);
#endif
return response;
}
}
#ifdef debug
printf("Timeout\n");
#endif
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return -1; // timeout
}
int SDCard__cmdx(int cmd, int arg) {
// _cs = 0;
GPIO_clear(_cs);
#ifdef debug
DBGPRINTF("SDCMDx:%u ", cmd);
#endif
// send a command
SPI_write(0x40 | cmd);
SPI_write(arg >> 24);
SPI_write(arg >> 16);
SPI_write(arg >> 8);
SPI_write(arg >> 0);
SPI_write(0x95);
// wait for the repsonse (response[7] == 0)
for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
int response = SPI_write(0xFF);
if(!(response & 0x80)) {
#ifdef debug
DBGPRINTF(" <%u\n", response);
#endif
return response;
}
}
#ifdef debug
DBGPRINTF_E("Timeout\n");
#endif
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return -1; // timeout
}
int SDCard__cmd58(uint32_t *ocr) {
// _cs = 0;
GPIO_clear(_cs);
int arg = 0;
// send a command
SPI_write(0x40 | 58);
SPI_write(arg >> 24);
SPI_write(arg >> 16);
SPI_write(arg >> 8);
SPI_write(arg >> 0);
SPI_write(0x95);
// wait for the repsonse (response[7] == 0)
for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
int response = SPI_write(0xFF);
if(!(response & 0x80)) {
*ocr = SPI_write(0xFF) << 24;
*ocr |= SPI_write(0xFF) << 16;
*ocr |= SPI_write(0xFF) << 8;
*ocr |= SPI_write(0xFF) << 0;
// printf("OCR = 0x%08X\n", *ocr);
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return response;
}
}
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return -1; // timeout
}
int SDCard__cmd8() {
// _cs = 0;
GPIO_clear(_cs);
// send a command
SPI_write(0x40 | SDCMD_SEND_IF_COND); // CMD8
SPI_write(0x00); // reserved
SPI_write(0x00); // reserved
SPI_write(0x01); // 3.3v
SPI_write(0xAA); // check pattern
SPI_write(0x87); // crc
// wait for the repsonse (response[7] == 0)
for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
char response[5];
response[0] = SPI_write(0xFF);
if(!(response[0] & 0x80)) {
for(int j=1; j<5; j++) {
response[j] = SPI_write(0xFF);
}
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return response[0];
}
}
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return -1; // timeout
}
int SDCard__read(uint8_t *buffer, int length) {
// _cs = 0;
GPIO_clear(_cs);
// read until start byte (0xFF)
while(SPI_write(0xFF) != 0xFE);
// read data
for(int i=0; i<length; i++) {
buffer[i] = SPI_write(0xFF);
}
SPI_write(0xFF); // checksum
SPI_write(0xFF);
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return 0;
}
int SDCard__write(const uint8_t *buffer, int length) {
// _cs = 0;
GPIO_clear(_cs);
// indicate start of block
SPI_write(0xFE);
// write the data
for(int i=0; i<length; i++) {
SPI_write(buffer[i]);
}
// write the checksum
SPI_write(0xFF);
SPI_write(0xFF);
// check the repsonse token
if((SPI_write(0xFF) & 0x1F) != 0x05) {
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return 1;
}
// wait for write to finish
while(SPI_write(0xFF) == 0);
// _cs = 1;
GPIO_set(_cs);
SPI_write(0xFF);
return 0;
}
static int ext_bits(uint8_t *data, int msb, int lsb)
{
int bits = 0;
int size = 1 + msb - lsb;
for(int i=0; i<size; i++) {
int position = lsb + i;
int byte = 15 - (position >> 3);
int bit = position & 0x7;
int value = (data[byte] >> bit) & 1;
bits |= value << i;
}
return bits;
}
uint32_t SDCard__sd_sectors()
{
// CMD9, Response R2 (R1 byte + 16-byte block read)
if(SDCard__cmdx(SDCMD_SEND_CSD, 0) != 0) {
DBGPRINTF_E("Didn't get a response from the disk\n");
return 0;
}
uint8_t csd[16];
if(SDCard__read(csd, 16) != 0) {
#if ENABLED(DEBUG_MESSAGES)
printf(EPFX "Couldn't read csd response from disk\n");
#endif
return 0;
}
// csd_structure : csd[127:126]
// c_size : csd[73:62]
// c_size_mult : csd[49:47]
// read_bl_len : csd[83:80] - the *maximum* read block length
uint32_t csd_structure = ext_bits(csd, 127, 126);
// printf("CSD_STRUCT = %d\n", csd_structure);
if (csd_structure == 0)
{
if (cardtype == SDCARD_V2HC)
{
DBGPRINTF_E("SDHC card with regular SD descriptor\n");
return 0;
}
uint32_t c_size = ext_bits(csd, 73, 62);
uint32_t c_size_mult = ext_bits(csd, 49, 47);
uint32_t read_bl_len = ext_bits(csd, 83, 80);
uint32_t block_len = 1 << read_bl_len;
uint32_t mult = 1 << (c_size_mult + 2);
uint32_t blocknr = (c_size + 1) * mult;
if (block_len >= 512) return blocknr * (block_len >> 9);
else return (blocknr * block_len) >> 9;
}
else if (csd_structure == 1)
{
if (cardtype != SDCARD_V2HC)
{
DBGPRINTF_E("SD V1 or V2 card with SDHC descriptor\n");
return 0;
}
uint32_t c_size = ext_bits(csd, 69, 48);
uint32_t blocknr = (c_size + 1) * 1024;
return blocknr;
}
else
{
DBGPRINTF_E("Invalid CSD %lu\n", csd_structure);
return 0;
}
// memory capacity = BLOCKNR * BLOCK_LEN
// where
// BLOCKNR = (C_SIZE+1) * MULT
// MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
// BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
// uint32_t block_len = 1 << read_bl_len;
// uint32_t mult = 1 << (c_size_mult + 2);
// uint32_t blocknr = (c_size + 1) * mult;
// uint32_t capacity = blocknr * block_len;
// uint32_t blocks = capacity / 512;
// uint32_t blocks;
// if (block_len >= 512) return blocknr * (block_len >> 9);
// else return (blocknr * block_len) >> 9;
// return blocks;
}