/*
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* (C) Copyright 2012
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* Dirk Eibach, Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include <common.h>
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#include <asm/io.h>
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#include <errno.h>
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#include <gdsys_fpga.h>
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enum {
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MCINT_SLAVE_LINK_CHANGED_EV = 1 << 7,
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MCINT_TX_ERROR_EV = 1 << 9,
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MCINT_TX_BUFFER_FREE = 1 << 10,
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MCINT_TX_PACKET_TRANSMITTED_EV = 1 << 11,
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MCINT_RX_ERROR_EV = 1 << 13,
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MCINT_RX_CONTENT_AVAILABLE = 1 << 14,
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MCINT_RX_PACKET_RECEIVED_EV = 1 << 15,
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};
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int mclink_probe(void)
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{
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unsigned int k;
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int slaves = 0;
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for (k = 0; k < CONFIG_SYS_MCLINK_MAX; ++k) {
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int timeout = 0;
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unsigned int ctr = 0;
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u16 mc_status;
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FPGA_GET_REG(k, mc_status, &mc_status);
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if (!(mc_status & (1 << 15)))
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break;
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FPGA_SET_REG(k, mc_control, 0x8000);
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FPGA_GET_REG(k, mc_status, &mc_status);
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while (!(mc_status & (1 << 14))) {
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udelay(100);
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if (ctr++ > 500) {
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timeout = 1;
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break;
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}
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FPGA_GET_REG(k, mc_status, &mc_status);
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}
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if (timeout)
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break;
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printf("waited %d us for mclink %d to come up\n", ctr * 100, k);
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slaves++;
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}
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return slaves;
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}
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int mclink_send(u8 slave, u16 addr, u16 data)
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{
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unsigned int ctr = 0;
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u16 int_status;
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u16 rx_cmd_status;
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u16 rx_cmd;
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/* reset interrupt status */
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FPGA_GET_REG(0, mc_int, &int_status);
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FPGA_SET_REG(0, mc_int, int_status);
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/* send */
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FPGA_SET_REG(0, mc_tx_address, addr);
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FPGA_SET_REG(0, mc_tx_data, data);
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FPGA_SET_REG(0, mc_tx_cmd, (slave & 0x03) << 14);
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FPGA_SET_REG(0, mc_control, 0x8001);
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/* wait for reply */
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FPGA_GET_REG(0, mc_int, &int_status);
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while (!(int_status & MCINT_RX_PACKET_RECEIVED_EV)) {
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udelay(100);
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if (ctr++ > 3)
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return -ETIMEDOUT;
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FPGA_GET_REG(0, mc_int, &int_status);
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}
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FPGA_GET_REG(0, mc_rx_cmd_status, &rx_cmd_status);
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rx_cmd = (rx_cmd_status >> 12) & 0x03;
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if (rx_cmd != 0)
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printf("mclink_send: received cmd %d, expected %d\n", rx_cmd,
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0);
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return 0;
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}
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int mclink_receive(u8 slave, u16 addr, u16 *data)
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{
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u16 rx_cmd_status;
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u16 rx_cmd;
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u16 int_status;
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unsigned int ctr = 0;
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/* send read request */
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FPGA_SET_REG(0, mc_tx_address, addr);
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FPGA_SET_REG(0, mc_tx_cmd,
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((slave & 0x03) << 14) | (1 << 12) | (1 << 0));
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FPGA_SET_REG(0, mc_control, 0x8001);
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/* wait for reply */
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FPGA_GET_REG(0, mc_int, &int_status);
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while (!(int_status & MCINT_RX_CONTENT_AVAILABLE)) {
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udelay(100);
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if (ctr++ > 3)
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return -ETIMEDOUT;
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FPGA_GET_REG(0, mc_int, &int_status);
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}
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/* check reply */
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FPGA_GET_REG(0, mc_rx_cmd_status, &rx_cmd_status);
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if ((rx_cmd_status >> 14) != slave) {
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printf("mclink_receive: reply from slave %d, expected %d\n",
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rx_cmd_status >> 14, slave);
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return -EINVAL;
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}
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rx_cmd = (rx_cmd_status >> 12) & 0x03;
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if (rx_cmd != 1) {
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printf("mclink_send: received cmd %d, expected %d\n",
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rx_cmd, 1);
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return -EIO;
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}
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FPGA_GET_REG(0, mc_rx_data, data);
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return 0;
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}
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