xgbe-i2c.c
/*
* AMD 10Gb Ethernet driver
*
* This file is available to you under your choice of the following two
* licenses:
*
* License 1: GPLv2
*
* Copyright (c) 2016 Advanced Micro Devices, Inc.
*
* This file is free software; you may copy, redistribute and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or (at
* your option) any later version.
*
* This file 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, see <http://www.gnu.org/licenses/>.
*
* This file incorporates work covered by the following copyright and
* permission notice:
* The Synopsys DWC ETHER XGMAC Software Driver and documentation
* (hereinafter "Software") is an unsupported proprietary work of Synopsys,
* Inc. unless otherwise expressly agreed to in writing between Synopsys
* and you.
*
* The Software IS NOT an item of Licensed Software or Licensed Product
* under any End User Software License Agreement or Agreement for Licensed
* Product with Synopsys or any supplement thereto. Permission is hereby
* granted, free of charge, to any person obtaining a copy of this software
* annotated with this license and the Software, to deal in the Software
* without restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished
* to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
* BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
* 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.
*
*
* License 2: Modified BSD
*
* Copyright (c) 2016 Advanced Micro Devices, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Advanced Micro Devices, Inc. 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 COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER> 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.
*
* This file incorporates work covered by the following copyright and
* permission notice:
* The Synopsys DWC ETHER XGMAC Software Driver and documentation
* (hereinafter "Software") is an unsupported proprietary work of Synopsys,
* Inc. unless otherwise expressly agreed to in writing between Synopsys
* and you.
*
* The Software IS NOT an item of Licensed Software or Licensed Product
* under any End User Software License Agreement or Agreement for Licensed
* Product with Synopsys or any supplement thereto. Permission is hereby
* granted, free of charge, to any person obtaining a copy of this software
* annotated with this license and the Software, to deal in the Software
* without restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished
* to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THIS SOFTWARE IS BEING DISTRIBUTED BY SYNOPSYS SOLELY ON AN "AS IS"
* BASIS AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. IN NO EVENT SHALL SYNOPSYS
* 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 <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/completion.h>
#include <linux/mutex.h>
#include "xgbe.h"
#include "xgbe-common.h"
#define XGBE_ABORT_COUNT 500
#define XGBE_DISABLE_COUNT 1000
#define XGBE_STD_SPEED 1
#define XGBE_INTR_RX_FULL BIT(IC_RAW_INTR_STAT_RX_FULL_INDEX)
#define XGBE_INTR_TX_EMPTY BIT(IC_RAW_INTR_STAT_TX_EMPTY_INDEX)
#define XGBE_INTR_TX_ABRT BIT(IC_RAW_INTR_STAT_TX_ABRT_INDEX)
#define XGBE_INTR_STOP_DET BIT(IC_RAW_INTR_STAT_STOP_DET_INDEX)
#define XGBE_DEFAULT_INT_MASK (XGBE_INTR_RX_FULL | \
XGBE_INTR_TX_EMPTY | \
XGBE_INTR_TX_ABRT | \
XGBE_INTR_STOP_DET)
#define XGBE_I2C_READ BIT(8)
#define XGBE_I2C_STOP BIT(9)
static int xgbe_i2c_abort(struct xgbe_prv_data *pdata)
{
unsigned int wait = XGBE_ABORT_COUNT;
/* Must be enabled to recognize the abort request */
XI2C_IOWRITE_BITS(pdata, IC_ENABLE, EN, 1);
/* Issue the abort */
XI2C_IOWRITE_BITS(pdata, IC_ENABLE, ABORT, 1);
while (wait--) {
if (!XI2C_IOREAD_BITS(pdata, IC_ENABLE, ABORT))
return 0;
usleep_range(500, 600);
}
return -EBUSY;
}
static int xgbe_i2c_set_enable(struct xgbe_prv_data *pdata, bool enable)
{
unsigned int wait = XGBE_DISABLE_COUNT;
unsigned int mode = enable ? 1 : 0;
while (wait--) {
XI2C_IOWRITE_BITS(pdata, IC_ENABLE, EN, mode);
if (XI2C_IOREAD_BITS(pdata, IC_ENABLE_STATUS, EN) == mode)
return 0;
usleep_range(100, 110);
}
return -EBUSY;
}
static int xgbe_i2c_disable(struct xgbe_prv_data *pdata)
{
unsigned int ret;
ret = xgbe_i2c_set_enable(pdata, false);
if (ret) {
/* Disable failed, try an abort */
ret = xgbe_i2c_abort(pdata);
if (ret)
return ret;
/* Abort succeeded, try to disable again */
ret = xgbe_i2c_set_enable(pdata, false);
}
return ret;
}
static int xgbe_i2c_enable(struct xgbe_prv_data *pdata)
{
return xgbe_i2c_set_enable(pdata, true);
}
static void xgbe_i2c_clear_all_interrupts(struct xgbe_prv_data *pdata)
{
XI2C_IOREAD(pdata, IC_CLR_INTR);
}
static void xgbe_i2c_disable_interrupts(struct xgbe_prv_data *pdata)
{
XI2C_IOWRITE(pdata, IC_INTR_MASK, 0);
}
static void xgbe_i2c_enable_interrupts(struct xgbe_prv_data *pdata)
{
XI2C_IOWRITE(pdata, IC_INTR_MASK, XGBE_DEFAULT_INT_MASK);
}
static void xgbe_i2c_write(struct xgbe_prv_data *pdata)
{
struct xgbe_i2c_op_state *state = &pdata->i2c.op_state;
unsigned int tx_slots;
unsigned int cmd;
/* Configured to never receive Rx overflows, so fill up Tx fifo */
tx_slots = pdata->i2c.tx_fifo_size - XI2C_IOREAD(pdata, IC_TXFLR);
while (tx_slots && state->tx_len) {
if (state->op->cmd == XGBE_I2C_CMD_READ)
cmd = XGBE_I2C_READ;
else
cmd = *state->tx_buf++;
if (state->tx_len == 1)
XI2C_SET_BITS(cmd, IC_DATA_CMD, STOP, 1);
XI2C_IOWRITE(pdata, IC_DATA_CMD, cmd);
tx_slots--;
state->tx_len--;
}
/* No more Tx operations, so ignore TX_EMPTY and return */
if (!state->tx_len)
XI2C_IOWRITE_BITS(pdata, IC_INTR_MASK, TX_EMPTY, 0);
}
static void xgbe_i2c_read(struct xgbe_prv_data *pdata)
{
struct xgbe_i2c_op_state *state = &pdata->i2c.op_state;
unsigned int rx_slots;
/* Anything to be read? */
if (state->op->cmd != XGBE_I2C_CMD_READ)
return;
rx_slots = XI2C_IOREAD(pdata, IC_RXFLR);
while (rx_slots && state->rx_len) {
*state->rx_buf++ = XI2C_IOREAD(pdata, IC_DATA_CMD);
state->rx_len--;
rx_slots--;
}
}
static void xgbe_i2c_clear_isr_interrupts(struct xgbe_prv_data *pdata,
unsigned int isr)
{
struct xgbe_i2c_op_state *state = &pdata->i2c.op_state;
if (isr & XGBE_INTR_TX_ABRT) {
state->tx_abort_source = XI2C_IOREAD(pdata, IC_TX_ABRT_SOURCE);
XI2C_IOREAD(pdata, IC_CLR_TX_ABRT);
}
if (isr & XGBE_INTR_STOP_DET)
XI2C_IOREAD(pdata, IC_CLR_STOP_DET);
}
static void xgbe_i2c_isr_task(unsigned long data)
{
struct xgbe_prv_data *pdata = (struct xgbe_prv_data *)data;
struct xgbe_i2c_op_state *state = &pdata->i2c.op_state;
unsigned int isr;
isr = XI2C_IOREAD(pdata, IC_RAW_INTR_STAT);
if (!isr)
goto reissue_check;
netif_dbg(pdata, intr, pdata->netdev,
"I2C interrupt received: status=%#010x\n", isr);
xgbe_i2c_clear_isr_interrupts(pdata, isr);
if (isr & XGBE_INTR_TX_ABRT) {
netif_dbg(pdata, link, pdata->netdev,
"I2C TX_ABRT received (%#010x) for target %#04x\n",
state->tx_abort_source, state->op->target);
xgbe_i2c_disable_interrupts(pdata);
state->ret = -EIO;
goto out;
}
/* Check for data in the Rx fifo */
xgbe_i2c_read(pdata);
/* Fill up the Tx fifo next */
xgbe_i2c_write(pdata);
out:
/* Complete on an error or STOP condition */
if (state->ret || XI2C_GET_BITS(isr, IC_RAW_INTR_STAT, STOP_DET))
complete(&pdata->i2c_complete);
reissue_check:
/* Reissue interrupt if status is not clear */
if (pdata->vdata->irq_reissue_support)
XP_IOWRITE(pdata, XP_INT_REISSUE_EN, 1 << 2);
}
static irqreturn_t xgbe_i2c_isr(int irq, void *data)
{
struct xgbe_prv_data *pdata = (struct xgbe_prv_data *)data;
if (pdata->isr_as_tasklet)
tasklet_schedule(&pdata->tasklet_i2c);
else
xgbe_i2c_isr_task((unsigned long)pdata);
return IRQ_HANDLED;
}
static void xgbe_i2c_set_mode(struct xgbe_prv_data *pdata)
{
unsigned int reg;
reg = XI2C_IOREAD(pdata, IC_CON);
XI2C_SET_BITS(reg, IC_CON, MASTER_MODE, 1);
XI2C_SET_BITS(reg, IC_CON, SLAVE_DISABLE, 1);
XI2C_SET_BITS(reg, IC_CON, RESTART_EN, 1);
XI2C_SET_BITS(reg, IC_CON, SPEED, XGBE_STD_SPEED);
XI2C_SET_BITS(reg, IC_CON, RX_FIFO_FULL_HOLD, 1);
XI2C_IOWRITE(pdata, IC_CON, reg);
}
static void xgbe_i2c_get_features(struct xgbe_prv_data *pdata)
{
struct xgbe_i2c *i2c = &pdata->i2c;
unsigned int reg;
reg = XI2C_IOREAD(pdata, IC_COMP_PARAM_1);
i2c->max_speed_mode = XI2C_GET_BITS(reg, IC_COMP_PARAM_1,
MAX_SPEED_MODE);
i2c->rx_fifo_size = XI2C_GET_BITS(reg, IC_COMP_PARAM_1,
RX_BUFFER_DEPTH);
i2c->tx_fifo_size = XI2C_GET_BITS(reg, IC_COMP_PARAM_1,
TX_BUFFER_DEPTH);
if (netif_msg_probe(pdata))
dev_dbg(pdata->dev, "I2C features: %s=%u, %s=%u, %s=%u\n",
"MAX_SPEED_MODE", i2c->max_speed_mode,
"RX_BUFFER_DEPTH", i2c->rx_fifo_size,
"TX_BUFFER_DEPTH", i2c->tx_fifo_size);
}
static void xgbe_i2c_set_target(struct xgbe_prv_data *pdata, unsigned int addr)
{
XI2C_IOWRITE(pdata, IC_TAR, addr);
}
static irqreturn_t xgbe_i2c_combined_isr(struct xgbe_prv_data *pdata)
{
xgbe_i2c_isr_task((unsigned long)pdata);
return IRQ_HANDLED;
}
static int xgbe_i2c_xfer(struct xgbe_prv_data *pdata, struct xgbe_i2c_op *op)
{
struct xgbe_i2c_op_state *state = &pdata->i2c.op_state;
int ret;
mutex_lock(&pdata->i2c_mutex);
reinit_completion(&pdata->i2c_complete);
ret = xgbe_i2c_disable(pdata);
if (ret) {
netdev_err(pdata->netdev, "failed to disable i2c master\n");
goto unlock;
}
xgbe_i2c_set_target(pdata, op->target);
memset(state, 0, sizeof(*state));
state->op = op;
state->tx_len = op->len;
state->tx_buf = op->buf;
state->rx_len = op->len;
state->rx_buf = op->buf;
xgbe_i2c_clear_all_interrupts(pdata);
ret = xgbe_i2c_enable(pdata);
if (ret) {
netdev_err(pdata->netdev, "failed to enable i2c master\n");
goto unlock;
}
/* Enabling the interrupts will cause the TX FIFO empty interrupt to
* fire and begin to process the command via the ISR.
*/
xgbe_i2c_enable_interrupts(pdata);
if (!wait_for_completion_timeout(&pdata->i2c_complete, HZ)) {
netdev_err(pdata->netdev, "i2c operation timed out\n");
ret = -ETIMEDOUT;
goto disable;
}
ret = state->ret;
if (ret) {
if (state->tx_abort_source & IC_TX_ABRT_7B_ADDR_NOACK)
ret = -ENOTCONN;
else if (state->tx_abort_source & IC_TX_ABRT_ARB_LOST)
ret = -EAGAIN;
}
disable:
xgbe_i2c_disable_interrupts(pdata);
xgbe_i2c_disable(pdata);
unlock:
mutex_unlock(&pdata->i2c_mutex);
return ret;
}
static void xgbe_i2c_stop(struct xgbe_prv_data *pdata)
{
if (!pdata->i2c.started)
return;
netif_dbg(pdata, link, pdata->netdev, "stopping I2C\n");
pdata->i2c.started = 0;
xgbe_i2c_disable_interrupts(pdata);
xgbe_i2c_disable(pdata);
xgbe_i2c_clear_all_interrupts(pdata);
if (pdata->dev_irq != pdata->i2c_irq)
devm_free_irq(pdata->dev, pdata->i2c_irq, pdata);
}
static int xgbe_i2c_start(struct xgbe_prv_data *pdata)
{
int ret;
if (pdata->i2c.started)
return 0;
netif_dbg(pdata, link, pdata->netdev, "starting I2C\n");
/* If we have a separate I2C irq, enable it */
if (pdata->dev_irq != pdata->i2c_irq) {
tasklet_init(&pdata->tasklet_i2c, xgbe_i2c_isr_task,
(unsigned long)pdata);
ret = devm_request_irq(pdata->dev, pdata->i2c_irq,
xgbe_i2c_isr, 0, pdata->i2c_name,
pdata);
if (ret) {
netdev_err(pdata->netdev, "i2c irq request failed\n");
return ret;
}
}
pdata->i2c.started = 1;
return 0;
}
static int xgbe_i2c_init(struct xgbe_prv_data *pdata)
{
int ret;
xgbe_i2c_disable_interrupts(pdata);
ret = xgbe_i2c_disable(pdata);
if (ret) {
dev_err(pdata->dev, "failed to disable i2c master\n");
return ret;
}
xgbe_i2c_get_features(pdata);
xgbe_i2c_set_mode(pdata);
xgbe_i2c_clear_all_interrupts(pdata);
return 0;
}
void xgbe_init_function_ptrs_i2c(struct xgbe_i2c_if *i2c_if)
{
i2c_if->i2c_init = xgbe_i2c_init;
i2c_if->i2c_start = xgbe_i2c_start;
i2c_if->i2c_stop = xgbe_i2c_stop;
i2c_if->i2c_xfer = xgbe_i2c_xfer;
i2c_if->i2c_isr = xgbe_i2c_combined_isr;
}