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/*
* This file is part of the coreboot project.
*
* Copyright (C) 2005 Yinghai Lu <yinghailu@gmail.com>
* Copyright (C) 2009 coresystems GmbH
* Copyright (C) 2013 Vladimir Serbinenko
*
* This program 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; version 2 of the License.
*
* This program 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, write to the Free Software
* Foundation, Inc.
*/
#include <device/smbus_def.h>
#include "pch.h"
static void smbus_delay(void)
{
inb(0x80);
}
static int smbus_wait_until_ready(u16 smbus_base)
{
unsigned loops = SMBUS_TIMEOUT;
unsigned char byte;
do {
smbus_delay();
if (--loops == 0)
break;
byte = inb(smbus_base + SMBHSTSTAT);
} while (byte & 1);
return loops ? 0 : -1;
}
static int smbus_wait_until_done(u16 smbus_base)
{
unsigned loops = SMBUS_TIMEOUT;
unsigned char byte;
do {
smbus_delay();
if (--loops == 0)
break;
byte = inb(smbus_base + SMBHSTSTAT);
} while ((byte & 1) || (byte & ~((1 << 6) | (1 << 0))) == 0);
return loops ? 0 : -1;
}
static int do_smbus_read_byte(unsigned smbus_base, unsigned device, unsigned address)
{
unsigned char global_status_register;
unsigned char byte;
if (smbus_wait_until_ready(smbus_base) < 0) {
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
/* Setup transaction */
/* Disable interrupts */
outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL);
/* Set the device I'm talking too */
outb(((device & 0x7f) << 1) | 1, smbus_base + SMBXMITADD);
/* Set the command/address... */
outb(address & 0xff, smbus_base + SMBHSTCMD);
/* Set up for a byte data read */
outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x2 << 2),
(smbus_base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
/* Clear the data byte... */
outb(0, smbus_base + SMBHSTDAT0);
/* Start the command */
outb((inb(smbus_base + SMBHSTCTL) | 0x40),
smbus_base + SMBHSTCTL);
/* Poll for transaction completion */
if (smbus_wait_until_done(smbus_base) < 0) {
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
global_status_register = inb(smbus_base + SMBHSTSTAT);
/* Ignore the "In Use" status... */
global_status_register &= ~(3 << 5);
/* Read results of transaction */
byte = inb(smbus_base + SMBHSTDAT0);
if (global_status_register != (1 << 1)) {
return SMBUS_ERROR;
}
return byte;
}
static int do_smbus_write_byte(unsigned smbus_base, unsigned device, unsigned address, unsigned data)
{
unsigned char global_status_register;
if (smbus_wait_until_ready(smbus_base) < 0)
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
/* Setup transaction */
/* Disable interrupts */
outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL);
/* Set the device I'm talking too */
outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD);
/* Set the command/address... */
outb(address & 0xff, smbus_base + SMBHSTCMD);
/* Set up for a byte data read */
outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x2 << 2),
(smbus_base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
/* Clear the data byte... */
outb(data, smbus_base + SMBHSTDAT0);
/* Start the command */
outb((inb(smbus_base + SMBHSTCTL) | 0x40),
smbus_base + SMBHSTCTL);
/* Poll for transaction completion */
if (smbus_wait_until_done(smbus_base) < 0)
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
global_status_register = inb(smbus_base + SMBHSTSTAT);
/* Ignore the "In Use" status... */
global_status_register &= ~(3 << 5);
/* Read results of transaction */
if (global_status_register != (1 << 1))
return SMBUS_ERROR;
return 0;
}
#ifdef __PRE_RAM__
static int do_smbus_block_write(unsigned smbus_base, unsigned device,
unsigned cmd, unsigned bytes, const u8 *buf)
{
u8 status;
if (smbus_wait_until_ready(smbus_base) < 0)
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
/* Setup transaction */
/* Disable interrupts */
outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL);
/* Set the device I'm talking too */
outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD);
/* Set the command/address... */
outb(cmd & 0xff, smbus_base + SMBHSTCMD);
/* Set up for a block data write */
outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x5 << 2),
(smbus_base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
/* set number of bytes to transfer */
outb(bytes, smbus_base + SMBHSTDAT0);
outb(*buf++, smbus_base + SMBBLKDAT);
bytes--;
/* Start the command */
outb((inb(smbus_base + SMBHSTCTL) | 0x40),
smbus_base + SMBHSTCTL);
while(!(inb(smbus_base + SMBHSTSTAT) & 1));
/* Poll for transaction completion */
do {
status = inb(smbus_base + SMBHSTSTAT);
if (status & ((1 << 4) | /* FAILED */
(1 << 3) | /* BUS ERR */
(1 << 2))) /* DEV ERR */
return SMBUS_ERROR;
if (status & 0x80) { /* Byte done */
outb(*buf++, smbus_base + SMBBLKDAT);
outb(status, smbus_base + SMBHSTSTAT);
}
} while(status & 0x01);
return 0;
}
static int do_smbus_block_read(unsigned smbus_base, unsigned device,
unsigned cmd, unsigned bytes, u8 *buf)
{
u8 status;
int bytes_read = 0;
if (smbus_wait_until_ready(smbus_base) < 0)
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
/* Setup transaction */
/* Disable interrupts */
outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL);
/* Set the device I'm talking too */
outb(((device & 0x7f) << 1) | 1, smbus_base + SMBXMITADD);
/* Set the command/address... */
outb(cmd & 0xff, smbus_base + SMBHSTCMD);
/* Set up for a block data read */
outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x5 << 2),
(smbus_base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
/* Start the command */
outb((inb(smbus_base + SMBHSTCTL) | 0x40),
smbus_base + SMBHSTCTL);
while(!(inb(smbus_base + SMBHSTSTAT) & 1));
/* Poll for transaction completion */
do {
status = inb(smbus_base + SMBHSTSTAT);
if (status & ((1 << 4) | /* FAILED */
(1 << 3) | /* BUS ERR */
(1 << 2))) /* DEV ERR */
return SMBUS_ERROR;
if (status & 0x80) { /* Byte done */
*buf = inb(smbus_base + SMBBLKDAT);
buf++;
bytes_read++;
outb(status, smbus_base + SMBHSTSTAT);
if (--bytes == 1) {
/* indicate that next byte is the last one */
outb(inb(smbus_base + SMBHSTCTL) | 0x20,
smbus_base + SMBHSTCTL);
}
}
} while(status & 0x01);
return bytes_read;
}
#endif
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