📄 sd.c
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/*****************************************************************************\
* efs - General purpose Embedded Filesystem library *
* --------------------- ----------------------------------- *
* *
* Filename : sd.c *
* Revision : Initial developement *
* Description : This file contains the functions needed to use efs for *
* accessing files on an SD-card. *
* *
* 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; version 2 *
* of the License. *
*
* 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. *
* *
* As a special exception, if other files instantiate templates or *
* use macros or inline functions from this file, or you compile this *
* file and link it with other works to produce a work based on this file, *
* this file does not by itself cause the resulting work to be covered *
* by the GNU General Public License. However the source code for this *
* file must still be made available in accordance with section (3) of *
* the GNU General Public License. *
* *
* This exception does not invalidate any other reasons why a work based *
* on this file might be covered by the GNU General Public License. *
* *
* (c)2006 Lennart Yseboodt *
* (c)2006 Michael De Nil *
\*****************************************************************************/
/*****************************************************************************/
#include "interface/sd.h"
/*****************************************************************************/
esint8 sd_Init(hwInterface *iface)
{
esint16 i;
euint8 resp;
/* Try to send reset command up to 100 times */
i=100;
do{
sd_Command(iface,0, 0, 0);
resp=sd_Resp8b(iface);
}
while(resp!=1 && i--);
if(resp!=1){
if(resp==0xff){
return(-1);
}
else{
sd_Resp8bError(iface,resp);
return(-2);
}
}
/* Wait till card is ready initialising (returns 0 on CMD1) */
/* Try up to 32000 times. */
i=32000;
do{
sd_Command(iface,1, 0, 0);
resp=sd_Resp8b(iface);
if(resp!=0)
sd_Resp8bError(iface,resp);
}
while(resp==1 && i--);
if(resp!=0){
sd_Resp8bError(iface,resp);
return(-3);
}
return(0);
}
/*****************************************************************************/
void sd_Command(hwInterface *iface,euint8 cmd, euint16 paramx, euint16 paramy)
{
if_spiSend(iface,0xff);
if_spiSend(iface,0x40 | cmd);
if_spiSend(iface,(euint8) (paramx >> 8)); /* MSB of parameter x */
if_spiSend(iface,(euint8) (paramx)); /* LSB of parameter x */
if_spiSend(iface,(euint8) (paramy >> 8)); /* MSB of parameter y */
if_spiSend(iface,(euint8) (paramy)); /* LSB of parameter y */
if_spiSend(iface,0x95); /* Checksum (should be only valid for first command (0) */
if_spiSend(iface,0xff); /* eat empty command - response */
}
/*****************************************************************************/
euint8 sd_Resp8b(hwInterface *iface)
{
euint8 i;
euint8 resp;
/* Respone will come after 1 - 8 pings */
for(i=0;i<8;i++){
resp = if_spiSend(iface,0xff);
if(resp != 0xff)
return(resp);
}
return(resp);
}
/*****************************************************************************/
euint16 sd_Resp16b(hwInterface *iface)
{
euint16 resp;
resp = ( sd_Resp8b(iface) << 8 ) & 0xff00;
resp |= if_spiSend(iface,0xff);
return(resp);
}
/*****************************************************************************/
void sd_Resp8bError(hwInterface *iface,euint8 value)
{
switch(value)
{
case 0x40:
//DBG((TXT("Argument out of bounds.\n")));
break;
case 0x20:
//DBG((TXT("Address out of bounds.\n")));
break;
case 0x10:
//DBG((TXT("Error during erase sequence.\n")));
break;
case 0x08:
//DBG((TXT("CRC failed.\n")));
break;
case 0x04:
//DBG((TXT("Illegal command.\n")));
break;
case 0x02:
//DBG((TXT("Erase reset (see SanDisk docs p5-13).\n")));
break;
case 0x01:
//DBG((TXT("Card is initialising.\n")));
break;
default:
//DBG((TXT("Unknown error 0x%x (see SanDisk docs p5-13).\n"),value));
break;
}
}
/*****************************************************************************/
esint8 sd_State(hwInterface *iface)
{
eint16 value;
sd_Command(iface,13, 0, 0);
value=sd_Resp16b(iface);
switch(value)
{
case 0x000:
return(1);
//break;
case 0x0001:
//DBG((TXT("Card is Locked.\n")));
break;
case 0x0002:
//DBG((TXT("WP Erase Skip, Lock/Unlock Cmd Failed.\n")));
break;
case 0x0004:
//DBG((TXT("General / Unknown error -- card broken?.\n")));
break;
case 0x0008:
//DBG((TXT("Internal card controller error.\n")));
break;
case 0x0010:
//DBG((TXT("Card internal ECC was applied, but failed to correct the data.\n")));
break;
case 0x0020:
//DBG((TXT("Write protect violation.\n")));
break;
case 0x0040:
//DBG((TXT("An invalid selection, sectors for erase.\n")));
break;
case 0x0080:
//DBG((TXT("Out of Range, CSD_Overwrite.\n")));
break;
default:
if(value>0x00FF)
sd_Resp8bError(iface,(euint8) (value>>8));
else
//DBG((TXT("Unknown error: 0x%x (see SanDisk docs p5-14).\n"),value));
break;
}
return(-1);
}
/*****************************************************************************/
/* ****************************************************************************
* WAIT ?? -- FIXME
* CMDWRITE
* WAIT
* CARD RESP
* WAIT
* DATA BLOCK OUT
* START BLOCK
* DATA
* CHKS (2B)
* BUSY...
*/
esint8 sd_writeSector(hwInterface *iface,euint32 address, euint8* buf)
{
euint32 place;
euint16 i;
euint16 t=0;
/*DBG((TXT("Trying to write %u to sector %u.\n"),(void *)&buf,address));*/
place=512*address;
sd_Command(iface,CMDWRITE, (euint16) (place >> 16), (euint16) place);
sd_Resp8b(iface); /* Card response */
if_spiSend(iface,0xfe); /* Start block */
for(i=0;i<512;i++)
if_spiSend(iface,buf[i]); /* Send data */
if_spiSend(iface,0xff); /* Checksum part 1 */
if_spiSend(iface,0xff); /* Checksum part 2 */
if_spiSend(iface,0xff);
while(if_spiSend(iface,0xff)!=0xff){
t++;
/* Removed NOP */
}
/*DBG((TXT("Nopp'ed %u times.\n"),t));*/
return(0);
}
/*****************************************************************************/
/* ****************************************************************************
* WAIT ?? -- FIXME
* CMDCMD
* WAIT
* CARD RESP
* WAIT
* DATA BLOCK IN
* START BLOCK
* DATA
* CHKS (2B)
*/
esint8 sd_readSector(hwInterface *iface,euint32 address, euint8* buf, euint16 len)
{
euint8 cardresp;
euint8 firstblock;
euint8 c;
euint16 fb_timeout=0xffff;
euint32 i;
euint32 place;
/*DBG((TXT("sd_readSector::Trying to read sector %u and store it at %p.\n"),address,&buf[0]));*/
place=512*address;
sd_Command(iface,CMDREAD, (euint16) (place >> 16), (euint16) place);
cardresp=sd_Resp8b(iface); /* Card response */
/* Wait for startblock */
do
firstblock=sd_Resp8b(iface);
while(firstblock==0xff && fb_timeout--);
if(cardresp!=0x00 || firstblock!=0xfe){
sd_Resp8bError(iface,firstblock);
return(-1);
}
for(i=0;i<512;i++){
c = if_spiSend(iface,0xff);
if(i<len)
buf[i] = c;
}
/* Checksum (2 byte) - ignore for now */
if_spiSend(iface,0xff);
if_spiSend(iface,0xff);
return(0);
}
/*****************************************************************************/
/* ****************************************************************************
calculates size of card from CSD
(extension by Martin Thomas, inspired by code from Holger Klabunde)
*/
esint8 sd_getDriveSize(hwInterface *iface, euint32* drive_size )
{
euint8 cardresp, i, by;
euint8 iob[16];
euint16 c_size, c_size_mult, read_bl_len;
sd_Command(iface, CMDREADCSD, 0, 0);
do {
cardresp = sd_Resp8b(iface);
} while ( cardresp != 0xFE );
//DBG((TXT("CSD:")));
for( i=0; i<16; i++) {
iob[i] = sd_Resp8b(iface);
//DBG((TXT(" %02x"), iob[i]));
}
//DBG((TXT("\n")));
if_spiSend(iface,0xff);
if_spiSend(iface,0xff);
c_size = iob[6] & 0x03; // bits 1..0
c_size <<= 10;
c_size += (euint16)iob[7]<<2;
c_size += iob[8]>>6;
by= iob[5] & 0x0F;
read_bl_len = 1;
read_bl_len <<= by;
by=iob[9] & 0x03;
by <<= 1;
by += iob[10] >> 7;
c_size_mult = 1;
c_size_mult <<= (2+by);
*drive_size = (euint32)(c_size+1) * (euint32)c_size_mult * (euint32)read_bl_len;
return 0;
}
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