freebsd-dev/sys/mips/nlm/board_eeprom.c

173 lines
4.3 KiB
C
Raw Normal View History

/*-
* Copyright (c) 2003-2012 Broadcom Corporation
* 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.
*
* THIS SOFTWARE IS PROVIDED BY BROADCOM ``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 BROADCOM 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/bus.h>
#include <dev/iicbus/iicoc.h>
#include <mips/nlm/hal/haldefs.h>
#include <mips/nlm/hal/iomap.h>
#include <mips/nlm/hal/mips-extns.h> /* needed by board.h */
#include <mips/nlm/board.h>
/*
* We have to read the EEPROM in early boot (now only for MAC addr)
* but later for board information. Use simple polled mode driver
* for I2C
*/
#define oc_read_reg(reg) nlm_read_reg(eeprom_i2c_base, reg)
#define oc_write_reg(reg, val) nlm_write_reg(eeprom_i2c_base, reg, val)
static uint64_t eeprom_i2c_base;
static int
oc_wait_on_status(uint8_t bit)
{
int tries = I2C_TIMEOUT;
uint8_t status;
do {
status = oc_read_reg(OC_I2C_STATUS_REG);
} while ((status & bit) != 0 && --tries > 0);
return (tries == 0 ? -1: 0);
}
static int
oc_rd_cmd(uint8_t cmd)
{
uint8_t data;
oc_write_reg(OC_I2C_CMD_REG, cmd);
if (oc_wait_on_status(OC_STATUS_TIP) < 0)
return (-1);
data = oc_read_reg(OC_I2C_DATA_REG);
return (data);
}
static int
oc_wr_cmd(uint8_t data, uint8_t cmd)
{
oc_write_reg(OC_I2C_DATA_REG, data);
oc_write_reg(OC_I2C_CMD_REG, cmd);
if (oc_wait_on_status(OC_STATUS_TIP) < 0)
return (-1);
return (0);
}
int
nlm_board_eeprom_read(int node, int bus, int addr, int offs, uint8_t *buf,
int sz)
{
int rd, i;
char *err = NULL;
eeprom_i2c_base = nlm_pcicfg_base(XLP_IO_I2C_OFFSET(node, bus)) +
XLP_IO_PCI_HDRSZ;
if (oc_wait_on_status(OC_STATUS_BUSY) < 0) {
err = "Not idle";
goto err_exit;
}
/* write start */
if (oc_wr_cmd(addr, OC_COMMAND_START)) {
err = "I2C write start failed.";
goto err_exit;
}
if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
err = "No ack after start";
goto err_exit_stop;
}
if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_AL) {
err = "I2C Bus Arbitration Lost";
goto err_exit_stop;
}
/* Write offset */
if (oc_wr_cmd(offs, OC_COMMAND_WRITE)) {
err = "I2C write slave offset failed.";
goto err_exit_stop;
}
if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
err = "No ack after write";
goto err_exit_stop;
}
/* read start */
if (oc_wr_cmd(addr | 1, OC_COMMAND_START)) {
err = "I2C read start failed.";
goto err_exit_stop;
}
if (oc_read_reg(OC_I2C_STATUS_REG) & OC_STATUS_NACK) {
err = "No ack after read start";
goto err_exit_stop;
}
for (i = 0; i < sz - 1; i++) {
if ((rd = oc_rd_cmd(OC_COMMAND_READ)) < 0) {
err = "I2C read data byte failed.";
goto err_exit_stop;
}
buf[i] = rd;
}
/* last byte */
if ((rd = oc_rd_cmd(OC_COMMAND_RDNACK)) < 0) {
err = "I2C read last data byte failed.";
goto err_exit_stop;
}
buf[sz - 1] = rd;
err_exit_stop:
oc_write_reg(OC_I2C_CMD_REG, OC_COMMAND_STOP);
if (oc_wait_on_status(OC_STATUS_BUSY) < 0)
printf("%s: stop failed", __func__);
err_exit:
if (err) {
printf("%s: Failed (%s)\n", __func__, err);
return (-1);
}
return (0);
}