diff options
Diffstat (limited to 'drivers/net/ethernet/amd/xgbe/xgbe-i2c.c')
| -rw-r--r-- | drivers/net/ethernet/amd/xgbe/xgbe-i2c.c | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-i2c.c b/drivers/net/ethernet/amd/xgbe/xgbe-i2c.c new file mode 100644 index 000000000000..0c7088a426e9 --- /dev/null +++ b/drivers/net/ethernet/amd/xgbe/xgbe-i2c.c @@ -0,0 +1,492 @@ +/* + * 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/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 irqreturn_t xgbe_i2c_isr(int irq, void *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); + 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); + + 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(int irq, struct xgbe_prv_data *pdata) +{ + if (!XI2C_IOREAD(pdata, IC_RAW_INTR_STAT)) + return IRQ_HANDLED; + + return xgbe_i2c_isr(irq, pdata); +} + +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) { + 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; +} |