Permalink
Switch branches/tags
Nothing to show
Find file Copy path
Fetching contributors…
Cannot retrieve contributors at this time
518 lines (475 sloc) 14.3 KB
////////////////////////////////////////////////////////////////////////////////
//
// Filename: sdspisim.cpp
//
// Project: Wishbone Controlled SD-Card Controller over SPI port
//
// Purpose: This library simulates the operation of a SPI commanded SD-Card,
// such as might be found on a XuLA2-LX25 board made by xess.com.
//
// This simulator is for testing use in a Verilator/C++ environment, where
// it would be used in place of the actual hardware.
//
// Creator: Dan Gisselquist, Ph.D.
// Gisselquist Technology, LLC
//
////////////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2015-2017, Gisselquist Technology, LLC
//
// This program is free software (firmware): 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.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY 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. (It's in the $(ROOT)/doc directory. Run make with no
// target there if the PDF file isn't present.) If not, see
// <http://www.gnu.org/licenses/> for a copy.
//
// License: GPL, v3, as defined and found on www.gnu.org,
// http://www.gnu.org/licenses/gpl.html
//
//
////////////////////////////////////////////////////////////////////////////////
//
//
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include "sdspisim.h"
static const unsigned
MICROSECONDS = 80, // Clocks in a microsecond
MILLISECONDS = MICROSECONDS * 1000,
tRESET = 4*MILLISECONDS; // Just a wild guess
/*
static const unsigned DEVID = 0x0115,
DEVESD = 0x014,
MICROSECONDS = 100,
MILLISECONDS = MICROSECONDS * 1000,
SECONDS = MILLISECONDS * 1000,
tW = 50 * MICROSECONDS, // write config cycle time
tBE = 32 * SECONDS,
tDP = 10 * SECONDS,
tRES = 30 * SECONDS,
// Shall we artificially speed up this process?
tPP = 12 * MICROSECONDS,
tSE = 15 * MILLISECONDS;
// or keep it at the original speed
// tPP = 1200 * MICROSECONDS,
// tSE = 1500 * MILLISECONDS;
*/
static const unsigned
CCS = 1; // 0: SDSC card, 1: SDHC or SDXC card
SDSPISIM::SDSPISIM(const bool debug) {
m_dev = NULL;
m_last_sck = 1;
m_block_address = (CCS==1);
m_host_supports_high_capacity = false;
m_powerup_busy = -1;
m_reset_state = SDSPI_POWERUP_RESET;
//
m_csd[ 0] = 0; // Normal SDcard, not high capacity
m_csd[ 1] = 0x0f;
m_csd[ 2] = 0x0f;
m_csd[ 3] = 0x32; // Can be either 0x32 (25MHz) or 0x5a (50MHz)
m_csd[ 4] = 0x5b; // Could also be 0x07b, if we supported more comands(?)
m_csd[ 5] = 0x59; // 9-> 2^9,or 512 bytes (10->1024, 11->2048, no othrs)
m_csd[ 6] = 0x00; // partial blocks allowed?
m_csd[ 7] = 0x00; // C_SIZE, 2'b00, then top 6 bits
m_csd[ 8] = 0; // C_SIZE, 22-bits, mid 8 bits
m_csd[ 9] = 0; // C_SIZE, 22-bits, bottom 8 bits
m_csd[10] = 0x7f;
m_csd[11] = 0x80;
m_csd[12] = 0x0a;
m_csd[13] = 0x40;
m_csd[14] = 0; // R/W: file format, copy, write protect, etc.
m_csd[15] = cmdcrc(15, m_csd);
// CID Register
m_cid[ 0] = 0xba;
m_cid[ 1] = 0xd0;
m_cid[ 2] = 0xda;
m_cid[ 3] = 0xdd;
m_cid[ 4] = 0;
m_cid[ 5] = 0xde;
m_cid[ 6] = 0xad;
m_cid[ 7] = 0xbe;
m_cid[ 8] = 0xef;
m_cid[ 9] = 0x20;
m_cid[10] = 0x16;
m_cid[11] = 0x05;
m_cid[12] = 0x26;
m_cid[13] = 0;
m_cid[14] = 0;
m_cid[15] = cmdcrc(15, m_cid);
// m_write_count = 0;
// m_ireg = m_oreg = 0;
// m_sreg = 0x01c;
// m_creg = 0x001; // Iinitial creg on delivery
//
m_reading_data = false;
m_have_token = false;
m_debug = debug;
}
void SDSPISIM::load(const char *fname) {
m_dev = fopen(fname, "r+b");
if (m_dev) {
unsigned long devln;
fseek(m_dev, 0l, SEEK_END);
devln = ftell(m_dev);
fseek(m_dev, 0l, SEEK_SET);
m_devblocks = devln>>9;
if (m_debug) printf("SDCARD: NBLOCKS = %ld\n", m_devblocks);
}
}
int SDSPISIM::operator()(const int csn, const int sck, const int mosi) {
// Keep track of a timer to determine when page program and erase
// cycles complete.
/*
if (m_write_count > 0) {
//
}
*/
m_delay++;
if (m_powerup_busy>0)
m_powerup_busy--;
if (csn) {
m_delay = 0;
m_cmdidx= 0;
m_rspidx= 0;
m_bitpos= 0;
m_delay = 0;
m_busy = false;
m_last_sck = sck;
m_syncd = false;
m_last_miso = 1;
m_dat_out = 0x0ff;
// Reset everything when not selected
return 0;
} else if (sck == m_last_sck) {
m_last_sck = sck;
return m_last_miso;
} else if (!m_last_sck) {
// Register our input on the rising edge
m_mosi = mosi;
m_syncd= true;
m_last_sck = sck;
return m_last_miso;
} if (!m_syncd) {
m_last_sck = sck;
return m_last_miso;
}
// Only change our output on the falling edge
m_last_sck = sck;
if (m_debug) printf("SDSPI: (%3d) [%d,%d,%d] ", m_delay, csn, sck, m_mosi);
// assert(m_delay > 20);
m_bitpos++;
m_dat_in = (m_dat_in<<1)|m_mosi;
if (m_debug) printf("(bitpos=%d,dat_in=%02x)\n", m_bitpos&7, m_dat_in&0x0ff);
if ((m_bitpos&7)==0) {
if (m_debug) printf("SDSPI--RX BYTE %02x\n", m_dat_in&0x0ff);
m_dat_out = 0xff;
if (m_reading_data) {
if (m_have_token) {
m_block_buf[m_rxloc++] = m_dat_in;
if (m_debug) printf("SDSPI: WR[%3d] = %02x\n", m_rxloc-1,
m_dat_in&0x0ff);
if (m_rxloc >= 512+2) {
unsigned crc, rxcrc;
crc = blockcrc(512, m_block_buf);
rxcrc = ((m_block_buf[512]&0x0ff)<<8)
|(m_block_buf[513]&0x0ff);
if (m_debug) printf("LEN = %d\n", m_rxloc);
if (m_debug) printf("CHECKING CRC: (rx) %04x =? %04x (calc)\n",
crc, rxcrc);
m_reading_data = false;
m_have_token = false;
if (rxcrc == crc)
m_dat_out = 5;
else {
m_dat_out = 0x0b;
assert(rxcrc == crc);
}
}
} else {
if ((m_dat_in&0x0ff) == 0x0fe) {
if (m_debug) printf("SDSPI: TOKEN!!\n");
m_have_token = true;
m_rxloc = 0;
} else if (m_debug)
printf("SDSPI: waiting on token\n");
}
} else if (m_cmdidx < 6) {
if (m_debug) printf("SDSPI: CMDIDX = %d\n", m_cmdidx);
// All commands *must* start with a 01... pair of bits.
if (m_cmdidx == 0)
assert((m_dat_in&0xc0)==0x40);
// Record the command for later processing
m_cmdbuf[m_cmdidx++] = m_dat_in;
} else if (m_cmdidx == 6) {
// We're going to start a response from here ...
m_rspidx = 0;
m_blkdly = 0;
m_blkidx = SDSPI_MAXBLKLEN;
if (m_debug) {
printf("SDSPI: CMDIDX = %d -- WE HAVE A COMMAND! [ ", m_cmdidx);
for(int i=0; i<6; i++)
printf("%02x ", m_cmdbuf[i] & 0xff);
printf("]\n"); fflush(stdout);
}
unsigned arg;
arg = ((((((m_cmdbuf[1]<<8)|(m_cmdbuf[2]&0x0ff))<<8)
|(m_cmdbuf[3]&0x0ff))<<8)
|(m_cmdbuf[4]&0x0ff));
arg &= 0x0ffffffff;
// Check the CRC
if (!check_cmdcrc(m_cmdbuf)) {
assert(0 && "BAD CRC");
m_rspbuf[0] = 0x09;
m_rspdly = 1;
} else if (m_altcmd_flag) {
switch(m_cmdbuf[0]&0x03f) {
case 41: // ACMD41 -- SD_SEND_OP_COND
// and start initialization sequence
assert((m_reset_state == SDSPI_RCVD_CMD8)||(m_reset_state == SDSPI_RCVD_ACMD41)||(m_reset_state == SDSPI_RESET_COMPLETE));
if((unsigned)m_powerup_busy>tRESET)
m_powerup_busy = tRESET;
assert((arg&0x0bfffffff) == 0);
m_rspbuf[0] = (m_powerup_busy)?1:0;
m_rspdly = 2;
m_host_supports_high_capacity = (m_cmdbuf[1]&0x40)?1:0;
m_reset_state = (m_powerup_busy)?
SDSPI_RCVD_ACMD41
:SDSPI_RESET_COMPLETE;
break;
case 51: // ACMD51
m_block_buf[0] = 0x0fe;
for(int j=0; j<8; j++)
m_block_buf[j+1] = m_csd[j];
m_blklen = 8;
add_block_crc(m_blklen, m_block_buf);
m_blkdly = 0;
m_blkidx = 0;
m_dat_out = 0;
break;
case 13: // ACMD13
case 22: // ACMD22
case 23: // ACMD23
case 42: // ACMD42
default: // Unimplemented command!
m_rspbuf[0] = 0x04;
m_rspdly = 4;
fprintf(stderr, "SDSPI ERR: Alt command ACMD%d not implemented!\n", m_cmdbuf[0]&0x03f);
assert(0 && "Not Implemented");
} m_altcmd_flag = false;
} else {
m_altcmd_flag = false;
memset(m_rspbuf, 0x0ff, SDSPI_RSPLEN);
if (m_debug) printf("SDSPI: Received a command 0x%02x (%d)\n",
m_cmdbuf[0], m_cmdbuf[0]&0x03f);
switch(m_cmdbuf[0]&0x3f) {
case 0: // CMD0 -- GO_IDLE_STATE
m_rspbuf[0] = 0x01;
m_rspdly = 4;
m_reset_state = SDSPI_CMD0_IDLE;
break;
case 1: // CMD1 -- SEND_OP_COND
assert((arg&0x0bfffffff) == 0);
m_rspbuf[0] = 0x02;
m_rspdly = 4;
m_host_supports_high_capacity = (m_cmdbuf[1]&0x40)?1:0;
break;
case 8: // CMD8 -- SEND_IF_COND
assert((arg&0x0fffff000) == 0);
m_rspbuf[0] = 0x00;
// See p82 for this format
m_rspbuf[1] = 0;
m_rspbuf[2] = 0;
// If we do not accept the voltage range
m_rspbuf[3] = 0;
// Now, check if we accept it
// We only accept 2.7-3.6V in this
// simulation.
if ((arg&0x0f00)==0x0100)
m_rspbuf[3] = 1;
m_rspbuf[4] = (char)(arg&0x0ff);
m_rspdly = 4;
assert((m_reset_state == SDSPI_CMD0_IDLE)||(m_reset_state == SDSPI_RCVD_CMD8));
m_reset_state = SDSPI_RCVD_CMD8;
break;
case 9: // CMD9 -- SEND_CSD
// Block read, returning start token,
// 16 bytes, then 2 crc bytes
assert(m_reset_state == SDSPI_IN_OPERATION);
m_rspbuf[0] = 0x00;
memset(m_block_buf, 0x0ff, SDSPI_MAXBLKLEN);
m_block_buf[0] = 0x0fe;
for(int j=0; j<16; j++)
m_block_buf[j+1] = m_csd[j];
m_blklen = 16;
add_block_crc(m_blklen, m_block_buf);
m_blkdly = 60;
m_blkidx = 0;
break;
case 10: // CMD10 -- SEND_CID
// Block read, returning start token,
// 16 bytes, then 2 crc bytes
assert(m_reset_state == SDSPI_IN_OPERATION);
m_rspbuf[0] = 0x00;
memset(m_block_buf, 0x0ff, SDSPI_MAXBLKLEN);
m_block_buf[0] = 0x0fe;
for(int j=0; j<16; j++)
m_block_buf[j+1] = m_cid[j];
m_blklen = 16;
add_block_crc(m_blklen, m_block_buf);
m_blkdly = 60;
m_blkidx = 0;
break;
case 13: // CMD13 -- SEND_STATUS
assert(m_reset_state == SDSPI_IN_OPERATION);
m_rspbuf[0] = 0x00;
m_rspbuf[1] = 0x00;
// if (m_wp_fault) m_rspbuf[1]|=0x20;
// if (m_err) m_rspbuf[1]|=0x04;
m_rspdly = 4;
break;
case 17: // CMD17 -- READ_SINGLE_BLOCK
assert(m_reset_state == SDSPI_IN_OPERATION);
m_rspbuf[0] = 0x00;
memset(m_block_buf, 0x0ff, SDSPI_MAXBLKLEN);
if (m_dev) {
if (m_debug) printf("Reading from block %08x of %08lx\n", arg, m_devblocks);
if (m_block_address) {
assert(arg < m_devblocks);
fseek(m_dev, arg<<9, SEEK_SET);
} else {
assert(arg < m_devblocks<<9);
fseek(m_dev, arg, SEEK_SET);
}
} m_block_buf[0] = 0x0fe;
m_blklen = 512; // (1<<m_csd[5]);
if (m_dev)
m_blklen = fread(&m_block_buf[1], m_blklen, 1, m_dev);
else
memset(&m_block_buf[1], 0, m_blklen);
m_blklen = (m_blklen != 512) ? 512 : m_blklen;
add_block_crc(m_blklen, m_block_buf);
m_blkdly = 60;
m_blkidx = 0;
break;
case 24: // CMD24 -- WRITE_BLOCK
m_reading_data = true;
m_have_token = false;
m_dat_out = 0;
break;
case 55: // CMD55 -- APP_CMD
m_rspbuf[0] = 0x00;
m_rspdly = 2;
m_altcmd_flag = true;
break;
case 58: // CMD58 -- READ_OCR, respond R7
// argument is stuff bits/dont care
m_rspbuf[0] = 0x00;
// See p112, Tbl 5-1 for this format
m_rspbuf[1] = ((m_powerup_busy)?0x80:0)
|(CCS?0x40:0);
m_rspbuf[2] = 0xff;// 2.7-3.6V supported
m_rspbuf[3] = 0x80;
m_rspbuf[4] = 0; // No low-voltage supt
m_rspdly = 4;
if (m_reset_state == SDSPI_RESET_COMPLETE)
m_reset_state = SDSPI_IN_OPERATION;
break;
case 6: // CMD6 -- SWITCH_FUNC
case 12: // CMD12 -- STOP_TRANSMISSION (!impl)
case 16: // CMD16 -- SET_BLOCKLEN
case 18: // CMD18 -- READ_MULTIPLE_BLOCK
case 25: // CMD25 -- WRITE_MULTIPLE_BLOCK
case 27: // CMD27 -- PROGRAM_CSD
case 32: // CMD32 -- ERASE_WR_BLK_START_ADDR
case 33: // CMD33 -- ERASE_WR_BLK_END_ADDR
case 38: // CMD38 -- ERASE
case 56: // CMD56 -- GEN_CMD
default: // Unimplemented command
m_rspbuf[0] = 0x04;
m_rspdly = 4;
if (m_debug) printf("SDSPI ERR: Command CMD%d not implemented!\n", m_cmdbuf[0]&0x03f);
fflush(stdout);
assert(0 && "Not Implemented");
}
} m_cmdidx++;
// If we are using blocks, add bytes for the start
// token and the two CRC bytes
m_blklen += 3;
} else if (m_rspdly > 0) {
assert((m_dat_in&0x0ff) == 0x0ff);
// A delay until a response is given
if (m_busy)
m_dat_out = 0;
m_rspdly--;
} else if (m_rspidx < SDSPI_RSPLEN) {
assert((m_dat_in&0x0ff) == 0x0ff);
m_dat_out = m_rspbuf[m_rspidx++];
} else if (m_blkdly > 0) {
assert((m_dat_in&0x0ff) == 0x0ff);
m_blkdly--;
} else if (m_blkidx < SDSPI_MAXBLKLEN) {
assert((m_dat_in&0x0ff) == 0x0ff);
m_dat_out = m_block_buf[m_blkidx++];
}
// else m_dat_out = 0x0ff; // So set already above
}
int result = (m_dat_out&0x80)?1:0;
m_dat_out <<= 1;
m_delay = 0;
m_last_miso = result;
fflush(stdout);
return result;
}
unsigned SDSPISIM::cmdcrc(int len, char *buf) const {
unsigned int fill = 0, taps = 0x12;
for(int i=0; i<len; i++) {
fill ^= buf[i];
for(int j=0; j<8; j++) {
if (fill&0x80)
fill = (fill<<1)^taps;
else
fill <<= 1;
}
}
fill &= 0x0fe; fill |= 1;
return fill;
}
bool SDSPISIM::check_cmdcrc(char *buf) const {
unsigned fill = cmdcrc(5, buf);
if (m_debug) printf("SDSPI: CRC-CHECK, should have a CRC of %02x\n", fill);
return (fill == (buf[5]&0x0ff));
}
unsigned SDSPISIM::blockcrc(int len, char *buf) const {
unsigned int fill = 0, taps = 0x1021;
bool dbg = (len == 512);
for(int i=0; i<len; i++) {
if (dbg) { printf("BUF[%3d] = %02x\n", i, buf[i]&0x0ff); }
fill ^= ((buf[i]&0x0ff) << 8);
for(int j=0; j<8; j++) {
if (fill&0x8000)
fill = (fill<<1)^taps;
else
fill <<= 1;
}
}
fill &= 0x0ffff;
if (dbg) { printf("BLOCKCRC(%d,??) = %04x\n", len, fill); }
return fill;
}
void SDSPISIM::add_block_crc(int len, char *buf) const {
unsigned fill = blockcrc(len, &buf[1]);
buf[len+1] = (fill >> 8)&0x0ff;
buf[len+2] = (fill )&0x0ff;
}