/*===============================================================*\
| Project: RTEMS generic MPC5200 BSP |
+-----------------------------------------------------------------+
| Partially based on the code references which are named below. |
| Adaptions, modifications, enhancements and any recent parts of |
| the code are: |
| Copyright (c) 2005 |
| Embedded Brains GmbH |
| Obere Lagerstr. 30 |
| D-82178 Puchheim |
| Germany |
| rtems@embedded-brains.de |
+-----------------------------------------------------------------+
| The license and distribution terms for this file may be |
| found in the file LICENSE in this distribution or at |
| |
| http://www.rtems.com/license/LICENSE. |
| |
+-----------------------------------------------------------------+
| this file contains the nvram functions |
\*===============================================================*/
/***********************************************************************/
/* */
/* Module: nvram.c */
/* Date: 07/17/2003 */
/* Purpose: RTEMS M93C64-based NV memory device driver */
/* */
/*---------------------------------------------------------------------*/
/* */
/* Description: M93C46 is a serial microwire EEPROM which contains */
/* 1Kbit (128 bytes/64 words) of non-volatile memory. */
/* The device can be coigured for byte- or word- */
/* access. The driver provides a file-like interface */
/* to this memory. */
/* */
/* MPC5x00 PIN settings: */
/* */
/* PSC3_6 (output) -> MC93C46 serial data in (D) */
/* PSC3_7 (input) -> MC93C46 serial data out (Q) */
/* PSC3_8 (output) -> MC93C46 chip select input (S) */
/* PSC3_9 (output) -> MC93C46 serial clock (C) */
/* */
/*---------------------------------------------------------------------*/
/* */
/* Code */
/* References: DS1307-based Non-Volatile memory device driver */
/* Module: nvram.c */
/* Project: RTEMS 4.6.0pre1 / MCF5206Elite BSP */
/* Version 1.2 */
/* Date: 11/04/2002 */
/* Author: Victor V. Vengerov */
/* Copyright: Copyright (C) 2000 OKTET Ltd.,St.-Petersburg,Russia */
/* */
/* The license and distribution terms for this file may be */
/* found in the file LICENSE in this distribution or at */
/* http://www.OARcorp.com/rtems/license.html. */
/* */
/*---------------------------------------------------------------------*/
/* */
/* Partially based on the code references which are named above. */
/* Adaptions, modifications, enhancements and any recent parts of */
/* the code are under the right of */
/* */
/* IPR Engineering, Dachauer Straße 38, D-80335 München */
/* Copyright(C) 2003 */
/* */
/*---------------------------------------------------------------------*/
/* */
/* IPR Engineering makes no representation or warranties with */
/* respect to the performance of this computer program, and */
/* specifically disclaims any responsibility for any damages, */
/* special or consequential, connected with the use of this program. */
/* */
/*---------------------------------------------------------------------*/
/* */
/* Version history: 1.0 */
/* */
/***********************************************************************/
#include <rtems.h>
#include <rtems/libio.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <bsp.h>
#include "../include/mpc5200.h"
#include "nvram.h"
#include "m93cxx.h"
/*
* Simple usec delay function using lower half of HARPO Time Base Register
*/
void wait_usec(unsigned long usec)
{
unsigned long start_count = 0, update_count;
unsigned long delay_count;
if(TMBASE_CLOCK < 1000000)
delay_count = (TMBASE_CLOCK * usec )/1000000;
else
delay_count = (TMBASE_CLOCK / 1000000) * usec;
TBL_READ(start_count);
update_count = start_count;
while((update_count - start_count) < delay_count)
TBL_READ(update_count);
}
/*
* Enable M93Cxx chip-write
*/
static void m93cxx_enable_write()
{
uint32_t header, i;
ENABLE_CHIP_SELECT;
WAIT(1);
header = M93C46_EWEN;
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
DISABLE_CHIP_SELECT;
return;
}
/*
* Disable M93Cxx chip-write
*/
static void m93cxx_disable_write()
{
uint32_t header, i;
ENABLE_CHIP_SELECT;
WAIT(1);
header = M93C46_EWDS;
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
DISABLE_CHIP_SELECT;
return;
}
/*
* Read one byte from specified offset
*/
static uint8_t m93cxx_read_byte(uint32_t offset)
{
uint8_t byte2read;
uint32_t header, tmp_offset, i;
#ifdef M93CXX_MODE_BYTE
uint8_t byte_recv = 0;
#else
uint32_t word_recv = 0;
#endif
ENABLE_CHIP_SELECT;
WAIT(1);
#ifdef M93CXX_MODE_BYTE
header = M93C46_READ(offset);
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
for(i = 0; i < 8; i++)
{
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
GET_DATA_BYTE_SHIFT(byte_recv);
}
byte_recv >>= 1;
byte2read = byte_recv;
#else
tmp_offset = offset/2;
header = M93C46_READ(tmp_offset);
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
for(i = 0; i < 16; i++)
{
DO_CLOCK_CYCLE;
WAIT(1);
GET_DATA_WORD_SHIFT(word_recv);
WAIT(1);
}
word_recv >>= 1;
if(offset%2)
{
byte2read = (uint8_t)((word_recv & 0xFF00) >> 8);
#ifdef NVRAM_DEBUG
printf("\nbyte_read(o) = %x", byte2read);
#endif
}
else
{
byte2read = (uint8_t)(word_recv & 0x00FF);
#ifdef NVRAM_DEBUG
printf("\nbyte_read(e) = %x", byte2read);
#endif
}
#endif
WAIT(1);
DISABLE_CHIP_SELECT;
return byte2read;
}
/*
* Write one byte to specified offset
*/
void m93cxx_write_byte(uint32_t offset, uint8_t byte2write)
{
uint32_t header, tmp_offset, i;
#ifdef M93CXX_MODE_BYTE
uint8_t byte_send;
#else
uint16_t word_send;
#endif
ENABLE_CHIP_SELECT;
WAIT(1);
#ifdef M93CXX_MODE_BYTE
header = M93C46_WRITE(offset);
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
byte_send = byte2write;
for(i = 0; i < 8; i++)
{
SET_DATA_BYTE_SHIFT(byte_send);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
}
#else
if(offset%2)
{
word_send = (uint16_t)m93cxx_read_byte(offset-1);
word_send |= (uint16_t)(m93cxx_read_byte(offset) << 8);
}
else
{
word_send = (uint16_t)m93cxx_read_byte(offset);
word_send |= (uint16_t)(m93cxx_read_byte(offset + 1) << 8);
}
tmp_offset = offset/2;
WAIT(1);
ENABLE_CHIP_SELECT;
WAIT(1);
header = M93C46_WRITE(tmp_offset);
for(i = 0; i < M93C46_CLOCK_CYCLES; i++)
{
MASK_HEAD_SHIFT(header);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
if(offset%2)
{
word_send = (word_send & 0x00FF) | ((uint16_t)(byte2write << 8));
#ifdef NVRAM_DEBUG
printf("\nword_send = %x", word_send);
#endif
}
else
{
word_send = (word_send & 0xFF00) | (uint16_t)byte2write;
#ifdef NVRAM_DEBUG
printf("\nword_send = %x", word_send);
#endif
}
for(i = 0; i < 16; i++)
{
SET_DATA_WORD_SHIFT(word_send);
WAIT(1);
DO_CLOCK_CYCLE;
WAIT(1);
}
DISABLE_CHIP_SELECT;
WAIT(1);
ENABLE_CHIP_SELECT;
WAIT(1);
CHECK_WRITE_BUSY;
#endif
WAIT(1);
DISABLE_CHIP_SELECT;
return;
}
/* nvram_driver_initialize --
* Non-volatile memory device driver initialization.
*/
rtems_device_driver nvram_driver_initialize(rtems_device_major_number major, rtems_device_minor_number minor, void *arg)
{
rtems_status_code sc;
/* enable PSC3_6/PSC3_7 as general purpose pins */
mpc5200.gpiosen |= (GPIO_PSC3_6 | GPIO_PSC3_7);
/* PSC3_6/PSC3_7 has normal CMOS output */
mpc5200.gpiosod &= ~(GPIO_PSC3_6 | GPIO_PSC3_7);
/* switch PSC3_6 (MC93C46 serial data in (D)) to low */
mpc5200.gpiosdo &= ~GPIO_PSC3_6;
/* PSC3_6 is an output (MC93C46 serial data in (D)) and PSC3_7 (MC93C46 serial data out (Q)) is an input pin */
mpc5200.gpiosdd |= GPIO_PSC3_6;
mpc5200.gpiosdd &= ~GPIO_PSC3_7;
/* disable PSC3_8 interrupt capabilities */
mpc5200.gpiosiie &= ~GPIO_PSC3_8;
/* enable PSC3_8 as general purpose pin */
mpc5200.gpiosie |= GPIO_PSC3_8;
/* PSC3_8 has normal CMOS output */
mpc5200.gpiosiod &= ~GPIO_PSC3_8;
/* switch PSC3_8 (MC93C46 chip select input (S)) to low (high activ) */
mpc5200.gpiosido &= ~GPIO_PSC3_8;
/* PSC3_8 is an output (MC93C46 chip select input (S)) pin */
mpc5200.gpiosidd |= GPIO_PSC3_8;
/* disable PSC3_9 interrupt capabilities */
mpc5200.gpiowue &= ~GPIO_PSC3_9;
/* enable PSC3_9 as general purpose pins */
mpc5200.gpiowe |= GPIO_PSC3_9;
/* PSC3_9 has normal CMOS output */
mpc5200.gpiowod &= ~GPIO_PSC3_9;
/* switch PSC3_9 (MC93C46 serial clock (C)) to low */
mpc5200.gpiowdo &= ~GPIO_PSC3_9;
/* PSC3_9 is an output (MC93C46 serial clock (C)) pin */
mpc5200.gpiowdd |= GPIO_PSC3_9;
sc = rtems_io_register_name("/dev/nvram", major, 0);
if(sc != RTEMS_SUCCESSFUL)
{
errno = EIO;
/*errno = ENODEV;*/
return RTEMS_UNSATISFIED;
}
else
return RTEMS_SUCCESSFUL;
}
/* nvram_driver_open --
* Non-volatile memory device driver open primitive.
*/
rtems_device_driver nvram_driver_open(rtems_device_major_number major, rtems_device_minor_number minor, void *arg)
{
return RTEMS_SUCCESSFUL;
}
/* nvram_driver_close --
* Non-volatile memory device driver close primitive.
*/
rtems_device_driver nvram_driver_close(rtems_device_major_number major, rtems_device_minor_number minor, void *arg)
{
return RTEMS_SUCCESSFUL;
}
/* nvram_driver_read --
* Non-volatile memory device driver read primitive.
*/
rtems_device_driver nvram_driver_read(rtems_device_major_number major, rtems_device_minor_number minor, void *arg)
{
rtems_libio_rw_args_t *args = arg;
uint32_t count, i;
#ifdef NVRAM_DEBUG
printf("\nread count = %2x", (int)(args->count));
printf("\nread offset = %2x", (int)(args->offset));
#endif
if((args->offset >= M93C46_NVRAM_SIZE) || (args->offset + args->count > M93C46_NVRAM_SIZE))
{
args->bytes_moved = 0;
errno = EINVAL;
return RTEMS_UNSATISFIED;
}
else
count = args->count;
for(i = 0; i < count; i++)
{
(args->buffer)[i] = m93cxx_read_byte((args->offset) + i);
(args->bytes_moved) += 1;
}
return RTEMS_SUCCESSFUL;
}
/* nvram_driver_write --
* Non-volatile memory device driver write primitive.
*/
rtems_device_driver nvram_driver_write(rtems_device_major_number major, rtems_device_minor_number minor, void *arg)
{
rtems_libio_rw_args_t *args = arg;
uint32_t count, i;
#ifdef NVRAM_DEBUG
printf("\nwrite count = %2x", (int)(args->count));
printf("\nwrite offset = %2x", (int)(args->offset));
#endif
if((args->offset >= M93C46_NVRAM_SIZE) || (args->offset + args->count > M93C46_NVRAM_SIZE))
{
args->bytes_moved = 0;
errno = EINVAL;
return RTEMS_UNSATISFIED;
}
else
count = args->count;
m93cxx_enable_write();
WAIT(1);
for(i = 0; i < count; i++)
{
m93cxx_write_byte((args->offset) + i, (args->buffer)[i]);
(args->bytes_moved) += 1;
}
WAIT(1);
m93cxx_disable_write();
return RTEMS_SUCCESSFUL;
}