NetBSD/sys/dev/mii/mii_bitbang.c

174 lines
4.3 KiB
C

/* $NetBSD: mii_bitbang.c,v 1.12 2008/05/04 17:06:09 xtraeme Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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 THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Common module for bit-bang'ing the MII.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mii_bitbang.c,v 1.12 2008/05/04 17:06:09 xtraeme Exp $");
#include <sys/param.h>
#include <sys/device.h>
#include <dev/mii/mii.h>
#include <dev/mii/mii_bitbang.h>
#define WRITE(x) \
do { \
ops->mbo_write(sc, (x)); \
delay(1); \
} while (/* CONSTCOND */ 0)
#define READ ops->mbo_read(sc)
#define MDO ops->mbo_bits[MII_BIT_MDO]
#define MDI ops->mbo_bits[MII_BIT_MDI]
#define MDC ops->mbo_bits[MII_BIT_MDC]
#define MDIRPHY ops->mbo_bits[MII_BIT_DIR_HOST_PHY]
#define MDIRHOST ops->mbo_bits[MII_BIT_DIR_PHY_HOST]
/*
* mii_bitbang_sync:
*
* Synchronize the MII.
*/
static void
mii_bitbang_sync(device_t sc, mii_bitbang_ops_t ops)
{
int i;
u_int32_t v;
v = MDIRPHY | MDO;
WRITE(v);
for (i = 0; i < 32; i++) {
WRITE(v | MDC);
WRITE(v);
}
}
/*
* mii_bitbang_sendbits:
*
* Send a series of bits to the MII.
*/
static void
mii_bitbang_sendbits(device_t sc, mii_bitbang_ops_t ops, uint32_t data,
int nbits)
{
int i;
u_int32_t v;
v = MDIRPHY;
WRITE(v);
for (i = 1 << (nbits - 1); i != 0; i >>= 1) {
if (data & i)
v |= MDO;
else
v &= ~MDO;
WRITE(v);
WRITE(v | MDC);
WRITE(v);
}
}
/*
* mii_bitbang_readreg:
*
* Read a PHY register by bit-bang'ing the MII.
*/
int
mii_bitbang_readreg(device_t sc, mii_bitbang_ops_t ops, int phy, int reg)
{
int val = 0, err = 0, i;
mii_bitbang_sync(sc, ops);
mii_bitbang_sendbits(sc, ops, MII_COMMAND_START, 2);
mii_bitbang_sendbits(sc, ops, MII_COMMAND_READ, 2);
mii_bitbang_sendbits(sc, ops, phy, 5);
mii_bitbang_sendbits(sc, ops, reg, 5);
/* Switch direction to PHY->host, without a clock transition. */
WRITE(MDIRHOST);
/* Turnaround clock. */
WRITE(MDIRHOST | MDC);
WRITE(MDIRHOST);
/* Check for error. */
err = READ & MDI;
/* Idle clock. */
WRITE(MDIRHOST | MDC);
WRITE(MDIRHOST);
for (i = 0; i < 16; i++) {
val <<= 1;
/* Read data prior to clock low-high transition. */
if (err == 0 && (READ & MDI) != 0)
val |= 1;
WRITE(MDIRHOST | MDC);
WRITE(MDIRHOST);
}
/* Set direction to host->PHY, without a clock transition. */
WRITE(MDIRPHY);
return (err ? 0 : val);
}
/*
* mii_bitbang_writereg:
*
* Write a PHY register by bit-bang'ing the MII.
*/
void
mii_bitbang_writereg(device_t sc, mii_bitbang_ops_t ops, int phy,
int reg, int val)
{
mii_bitbang_sync(sc, ops);
mii_bitbang_sendbits(sc, ops, MII_COMMAND_START, 2);
mii_bitbang_sendbits(sc, ops, MII_COMMAND_WRITE, 2);
mii_bitbang_sendbits(sc, ops, phy, 5);
mii_bitbang_sendbits(sc, ops, reg, 5);
mii_bitbang_sendbits(sc, ops, MII_COMMAND_ACK, 2);
mii_bitbang_sendbits(sc, ops, val, 16);
WRITE(MDIRPHY);
}