tinySA/demos/ARM7-LPC214x-GCC/mmcsd.c

390 lines
8.8 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT 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 3 of the License, or
(at your option) any later version.
ChibiOS/RT 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, see <http://www.gnu.org/licenses/>.
*/
#include <ch.h>
#include <pal.h>
#include "board.h"
#include "lpc214x_ssp.h"
#include "mmcsd.h"
EventSource MMCInsertEventSource, MMCRemoveEventSource;
static VirtualTimer vt;
static int cnt;
/*
* Subsystem initialization.
*/
void InitMMC(void) {
chEvtInit(&MMCInsertEventSource);
chEvtInit(&MMCRemoveEventSource);
cnt = POLLING_INTERVAL;
}
void tmrfunc(void *par) {
if (cnt) {
if (!palReadPad(IOPORT_B, PB_CP1)) {
if (!--cnt)
chEvtBroadcastI(&MMCInsertEventSource);
}
else
cnt = POLLING_INTERVAL;
}
else {
if (palReadPad(IOPORT_B, PB_CP1)) {
cnt = POLLING_INTERVAL;
chEvtBroadcastI(&MMCRemoveEventSource);
}
}
chVTSetI(&vt, 10, tmrfunc, NULL);
}
/*
* Starts the card polling service.
*/
void mmcStartPolling(void) {
chSysLock();
if (!chVTIsArmedI(&vt)) {
chVTSetI(&vt, 10, tmrfunc, NULL);
cnt = POLLING_INTERVAL;
}
chSysUnlock();
}
/*
* Stops the card polling service.
*/
void mmcStopPolling(void) {
chSysLock();
if (chVTIsArmedI(&vt)) {
chVTResetI(&vt);
cnt = POLLING_INTERVAL;
}
chSysUnlock();
}
/*
* Returns TRUE if the card is safely inserted in the reader.
*/
bool_t mmcCardInserted (void) {
return cnt == 0;
}
static void wait(void) {
int i;
uint8_t buf[4];
for (i = 0; i < 16; i++) {
sspRW(buf, NULL, 1);
if (buf[0] == 0xFF)
break;
}
/* Looks like it is a loooong wait.*/
while (TRUE) {
sspRW(buf, NULL, 1);
if (buf[0] == 0xFF)
break;
#ifdef NICE_WAITING
chThdSleep(1); /* Trying to be nice with the other threads.*/
#endif
}
}
static void sendhdr(uint8_t cmd, uint32_t arg) {
uint8_t buf[6];
/*
* Wait for the bus to become idle if a write operation was in progress.
*/
wait();
buf[0] = 0x40 | cmd;
buf[1] = arg >> 24;
buf[2] = arg >> 16;
buf[3] = arg >> 8;
buf[4] = arg;
buf[5] = 0x95; /* Valid for CMD0 ingnored by other commands. */
sspRW(NULL, buf, 6);
}
static uint8_t recvr1(void) {
int i;
uint8_t r1[1];
for (i = 0; i < 9; i++) {
sspRW(r1, NULL, 1);
if (r1[0] != 0xFF)
return r1[0];
}
return 0xFF; /* Timeout.*/
}
static bool_t getdata(uint8_t *buf, uint32_t n) {
int i;
for (i = 0; i < MMC_WAIT_DATA; i++) {
sspRW(buf, NULL, 1);
if (buf[0] == 0xFE) {
sspRW(buf, NULL, n);
sspRW(NULL, NULL, 2); /* CRC ignored.*/
return FALSE;
}
}
return TRUE; /* Timeout.*/
}
/*
* Initializes a card after the power up by selecting the SPI mode.
*/
bool_t mmcInit(void) {
/*
* Starting initialization with slow clock mode.
*/
ssp_setup(254, CR0_DSS8BIT | CR0_FRFSPI | CR0_CLOCKRATE(0), 0);
/*
* SPI mode selection.
*/
sspRW(NULL, NULL, 16); /* 128 clock pulses without ~CS asserted. */
int i = 0;
while (TRUE) {
if (mmcSendCommand(CMDGOIDLE, 0) == 0x01)
break;
if (++i >= CMD0_RETRY)
return TRUE;
chThdSleep(10);
}
/*
* Initialization.
*/
i = 0;
while (TRUE) {
uint8_t b = mmcSendCommand(CMDINIT, 0);
if (b == 0x00)
break;
if (b != 0x01)
return TRUE;
if (++i >= CMD1_RETRY)
return TRUE;
chThdSleep(10);
}
/*
* Full speed.
*/
ssp_setup(2, CR0_DSS8BIT | CR0_FRFSPI | CR0_CLOCKRATE(0), 0);
return FALSE;
}
/*
* Sends a simple command and returns a R1-type response.
*/
uint8_t mmcSendCommand(uint8_t cmd, uint32_t arg) {
uint8_t r1;
sspAcquireBus();
sendhdr(cmd, arg);
r1 = recvr1();
sspReleaseBus();
return r1;
}
/*
* Reads the card info record.
* @param data the pointer to a \p MMCCSD structure
* @return \p TRUE if an error happened
*/
bool_t mmcGetSize(MMCCSD *data) {
uint8_t buf[16];
sspAcquireBus();
sendhdr(CMDREADCSD, 0);
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
if (getdata(buf, 16)) {
sspReleaseBus();
return TRUE;
}
sspReleaseBus();
/* csize * multiplier */
data->csize = (((buf[6] & 3) << 10) | (buf[7] << 2) | (buf[8] >> 6)) *
(1 << (2 + (((buf[9] & 3) << 1) | (buf[10] >> 7))));
data->rdblklen = 1 << (buf[5] & 15);
return FALSE;
}
/*
* Reads a block.
* @param blknum the block number
* @param buf the pointer to the read buffer
* @return \p TRUE if an error happened
*/
bool_t mmcRead(uint8_t *buf, uint32_t blknum) {
sspAcquireBus();
sendhdr(CMDREAD, blknum << 9);
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
if (getdata(buf, 512)) {
sspReleaseBus();
return TRUE;
}
sspReleaseBus();
return FALSE;
}
/*
* Reads multiple blocks.
* @param blknum the initial block
* @param n the number of blocks
* @param buf the pointer to the read buffer
* @return \p TRUE if an error happened
*/
bool_t mmcReadMultiple(uint8_t *buf, uint32_t blknum, uint32_t n) {
static const uint8_t stopcmd[] = {0x40 | CMDSTOP, 0, 0, 0, 0, 1, 0xFF};
sspAcquireBus();
sendhdr(CMDREADMULTIPLE, blknum << 9);
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
while (n) {
if (getdata(buf, 512)) {
sspReleaseBus();
return TRUE;
}
buf += 512;
n--;
}
sspRW(NULL, (uint8_t *)stopcmd, sizeof(stopcmd));
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
sspReleaseBus();
return FALSE;
}
/*
* Writes a block.
* @param blknum the block number
* @param buf the pointer to the write buffer
* @return \p TRUE if an error happened
* @note The function DOES NOT wait for the SPI bus to become free after
* sending the data, the bus check is done before sending commands to
* the card, this allows to not make useless busy waiting. The invoking
* thread can do other things while the data is being written.
*/
bool_t mmcWrite(uint8_t *buf, uint32_t blknum) {
static const uint8_t start[] = {0xFF, 0xFE};
uint8_t b[4];
sspAcquireBus();
sendhdr(CMDWRITE, blknum << 9);
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
sspRW(NULL, (uint8_t *)start, 2); /* Data prologue.*/
sspRW(NULL, buf, 512); /* Data.*/
sspRW(NULL, NULL, 2); /* CRC ignored in this version.*/
sspRW(b, NULL, 1);
sspReleaseBus();
if ((b[0] & 0x1F) != 0x05)
return TRUE;
return FALSE;
}
/*
* Writes multiple blocks.
* @param blknum the initial block
* @param n the number of blocks
* @param buf the pointer to the write buffer
* @return \p TRUE if an error happened
* @note The function DOES NOT wait for the SPI bus to become free after
* sending the data, the bus check is done before sending commands to
* the card, this allows to not make useless busy waiting. The invoking
* thread can do other things while the data is being written.
*/
bool_t mmcWriteMultiple(uint8_t *buf, uint32_t blknum, uint32_t n) {
static const uint8_t start[] = {0xFF, 0xFC},
stop[] = {0xFD, 0xFF};
uint8_t b[4];
sspAcquireBus();
sendhdr(CMDWRITEMULTIPLE, blknum << 9);
if (recvr1() != 0x00) {
sspReleaseBus();
return TRUE;
}
while (n) {
sspRW(NULL, (uint8_t *)start, sizeof(start)); /* Data prologue.*/
sspRW(NULL, buf, 512); /* Data.*/
sspRW(NULL, NULL, 2); /* CRC ignored in this version.*/
sspRW(b, NULL, 1);
if ((b[0] & 0x1F) != 0x05) {
sspReleaseBus();
return TRUE;
}
wait();
buf += 512;
n--;
}
sspRW(NULL, (uint8_t *)stop, sizeof(stop)); /* Stops the transfer.*/
sspReleaseBus();
return FALSE;
}
/*
* Makes sure that pending operations are completed before returning.
*/
void mmcSynch(void) {
uint8_t buf[4];
sspAcquireBus();
while (TRUE) {
sspRW(buf, NULL, 1);
if (buf[0] == 0xFF)
break;
#ifdef NICE_WAITING
chThdSleep(1); /* Trying to be nice with the other threads.*/
#endif
}
sspReleaseBus();
}