nes-proj/drivers/platform/wismote/dev/xmem.c

274 lines
6.6 KiB
C

/*
* Copyright (c) 2006, Swedish Institute of Computer Science
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/**
* \file
* Device driver for the ST M25P80 40MHz 1Mbyte external memory.
* \author
* Björn Grönvall <bg@sics.se>
* Sumankumar Panchal <suman@ece.iisc.ernet.in>
*
*
* Data is written bit inverted (~-operator) to flash so that
* unwritten data will read as zeros (UNIX style).
*/
#include "contiki.h"
#include <stdio.h>
#include <string.h>
#include "dev/spi.h"
#include "dev/xmem.h"
#include "dev/watchdog.h"
#if 0
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...) do {} while (0)
#endif
#define SPI_FLASH_INS_WREN 0x06
#define SPI_FLASH_INS_WRDI 0x04
#define SPI_FLASH_INS_RDSR 0x05
#define SPI_FLASH_INS_WRSR 0x01
#define SPI_FLASH_INS_READ 0x03
#define SPI_FLASH_INS_FAST_READ 0x0b
#define SPI_FLASH_INS_PP 0x02
#define SPI_FLASH_INS_SE 0xd8
#define SPI_FLASH_INS_BE 0xc7
#define SPI_FLASH_INS_DP 0xb9
#define SPI_FLASH_INS_RES 0xab
/*---------------------------------------------------------------------------*/
static void
write_enable(void)
{
int s;
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE(SPI_FLASH_INS_WREN);
SPI_FLASH_DISABLE();
splx(s);
}
/*---------------------------------------------------------------------------*/
static unsigned
read_status_register(void)
{
unsigned char u;
int s;
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE(SPI_FLASH_INS_RDSR);
SPI_FLUSH();
SPI_READ(u);
SPI_FLASH_DISABLE();
splx(s);
return u;
}
/*---------------------------------------------------------------------------*/
/*
* Wait for a write/erase operation to finish.
*/
static unsigned
wait_ready(void)
{
unsigned u;
do {
u = read_status_register();
watchdog_periodic();
} while(u & 0x01); /* WIP=1, write in progress */
return u;
}
/*---------------------------------------------------------------------------*/
/*
* Erase 64k bytes of data. It takes about 1s before WIP goes low!
*/
static void
erase_sector(unsigned long offset)
{
int s;
wait_ready();
write_enable();
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE_FAST(SPI_FLASH_INS_SE);
SPI_WRITE_FAST(offset >> 16); /* MSB */
SPI_WRITE_FAST(offset >> 8);
SPI_WRITE_FAST(offset >> 0); /* LSB */
SPI_WAITFORTx_ENDED();
SPI_FLASH_DISABLE();
splx(s);
}
/*---------------------------------------------------------------------------*/
/*
* Initialize external flash *and* SPI bus!
*/
void
xmem_init(void)
{
int s;
spi_init();
P4DIR |= BIT0;
/* Release from Deep Power-down */
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE_FAST(SPI_FLASH_INS_RES);
SPI_WAITFORTx_ENDED();
SPI_FLASH_DISABLE(); /* Unselect flash. */
splx(s);
SPI_FLASH_UNHOLD();
}
/*---------------------------------------------------------------------------*/
int
xmem_pread(void *_p, int size, unsigned long offset)
{
unsigned char *p = _p;
const unsigned char *end = p + size;
int s;
wait_ready();
ENERGEST_ON(ENERGEST_TYPE_FLASH_READ);
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE_FAST(SPI_FLASH_INS_READ);
SPI_WRITE_FAST(offset >> 16); /* MSB */
SPI_WRITE_FAST(offset >> 8);
SPI_WRITE_FAST(offset >> 0); /* LSB */
SPI_WAITFORTx_ENDED();
SPI_FLUSH();
for(; p < end; p++) {
unsigned char u;
SPI_READ(u);
*p = ~u;
}
SPI_FLASH_DISABLE();
splx(s);
ENERGEST_OFF(ENERGEST_TYPE_FLASH_READ);
return size;
}
/*---------------------------------------------------------------------------*/
static const unsigned char *
program_page(unsigned long offset, const unsigned char *p, int nbytes)
{
const unsigned char *end = p + nbytes;
int s;
wait_ready();
write_enable();
s = splhigh();
SPI_FLASH_ENABLE();
SPI_WRITE_FAST(SPI_FLASH_INS_PP);
SPI_WRITE_FAST(offset >> 16); /* MSB */
SPI_WRITE_FAST(offset >> 8);
SPI_WRITE_FAST(offset >> 0); /* LSB */
for(; p < end; p++) {
SPI_WRITE_FAST(~*p);
}
SPI_WAITFORTx_ENDED();
SPI_FLASH_DISABLE();
splx(s);
return p;
}
/*---------------------------------------------------------------------------*/
int
xmem_pwrite(const void *_buf, int size, unsigned long addr)
{
const unsigned char *p = _buf;
const unsigned long end = addr + size;
unsigned long i, next_page;
ENERGEST_ON(ENERGEST_TYPE_FLASH_WRITE);
for(i = addr; i < end;) {
next_page = (i | 0xff) + 1;
if(next_page > end) {
next_page = end;
}
p = program_page(i, p, next_page - i);
i = next_page;
}
ENERGEST_OFF(ENERGEST_TYPE_FLASH_WRITE);
return size;
}
/*---------------------------------------------------------------------------*/
int
xmem_erase(long size, unsigned long addr)
{
unsigned long end = addr + size;
if(size % XMEM_ERASE_UNIT_SIZE != 0) {
PRINTF("xmem_erase: bad size\n");
return -1;
}
if(addr % XMEM_ERASE_UNIT_SIZE != 0) {
PRINTF("xmem_erase: bad offset\n");
return -1;
}
for (; addr < end; addr += XMEM_ERASE_UNIT_SIZE) {
erase_sector(addr);
}
return size;
}
/*---------------------------------------------------------------------------*/