SDCard.c

/*****************************************************************************
 *                                                                            *
 * 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;
}