Dirk Eibach | 7c8f97d | 2013-06-26 16:04:27 +0200 | [diff] [blame] | 1 | /* |
| 2 | * (C) Copyright 2012 |
| 3 | * Dirk Eibach, Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc |
| 4 | * |
Tom Rini | be314fa | 2013-07-26 15:32:59 -0400 | [diff] [blame] | 5 | * SPDX-License-Identifier: GPL-2.0+ |
Dirk Eibach | 7c8f97d | 2013-06-26 16:04:27 +0200 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <common.h> |
| 9 | #include <asm/io.h> |
| 10 | #include <errno.h> |
| 11 | |
| 12 | #include <gdsys_fpga.h> |
| 13 | |
| 14 | enum { |
| 15 | MCINT_SLAVE_LINK_CHANGED_EV = 1 << 7, |
| 16 | MCINT_TX_ERROR_EV = 1 << 9, |
| 17 | MCINT_TX_BUFFER_FREE = 1 << 10, |
| 18 | MCINT_TX_PACKET_TRANSMITTED_EV = 1 << 11, |
| 19 | MCINT_RX_ERROR_EV = 1 << 13, |
| 20 | MCINT_RX_CONTENT_AVAILABLE = 1 << 14, |
| 21 | MCINT_RX_PACKET_RECEIVED_EV = 1 << 15, |
| 22 | }; |
| 23 | |
| 24 | int mclink_probe(void) |
| 25 | { |
| 26 | unsigned int k; |
| 27 | int slaves = 0; |
| 28 | |
| 29 | for (k = 0; k < CONFIG_SYS_MCLINK_MAX; ++k) { |
| 30 | int timeout = 0; |
| 31 | unsigned int ctr = 0; |
| 32 | u16 mc_status; |
| 33 | |
| 34 | FPGA_GET_REG(k, mc_status, &mc_status); |
| 35 | |
| 36 | if (!(mc_status & (1 << 15))) |
| 37 | break; |
| 38 | |
| 39 | FPGA_SET_REG(k, mc_control, 0x8000); |
| 40 | |
| 41 | FPGA_GET_REG(k, mc_status, &mc_status); |
| 42 | while (!(mc_status & (1 << 14))) { |
| 43 | udelay(100); |
| 44 | if (ctr++ > 500) { |
| 45 | timeout = 1; |
| 46 | break; |
| 47 | } |
| 48 | FPGA_GET_REG(k, mc_status, &mc_status); |
| 49 | } |
| 50 | if (timeout) |
| 51 | break; |
| 52 | |
| 53 | printf("waited %d us for mclink %d to come up\n", ctr * 100, k); |
| 54 | |
| 55 | slaves++; |
| 56 | } |
| 57 | |
| 58 | return slaves; |
| 59 | } |
| 60 | |
| 61 | int mclink_send(u8 slave, u16 addr, u16 data) |
| 62 | { |
| 63 | unsigned int ctr = 0; |
| 64 | u16 int_status; |
| 65 | u16 rx_cmd_status; |
| 66 | u16 rx_cmd; |
| 67 | |
| 68 | /* reset interrupt status */ |
| 69 | FPGA_GET_REG(0, mc_int, &int_status); |
| 70 | FPGA_SET_REG(0, mc_int, int_status); |
| 71 | |
| 72 | /* send */ |
| 73 | FPGA_SET_REG(0, mc_tx_address, addr); |
| 74 | FPGA_SET_REG(0, mc_tx_data, data); |
| 75 | FPGA_SET_REG(0, mc_tx_cmd, (slave & 0x03) << 14); |
| 76 | FPGA_SET_REG(0, mc_control, 0x8001); |
| 77 | |
| 78 | /* wait for reply */ |
| 79 | FPGA_GET_REG(0, mc_int, &int_status); |
| 80 | while (!(int_status & MCINT_RX_PACKET_RECEIVED_EV)) { |
| 81 | udelay(100); |
| 82 | if (ctr++ > 3) |
| 83 | return -ETIMEDOUT; |
| 84 | FPGA_GET_REG(0, mc_int, &int_status); |
| 85 | } |
| 86 | |
| 87 | FPGA_GET_REG(0, mc_rx_cmd_status, &rx_cmd_status); |
| 88 | rx_cmd = (rx_cmd_status >> 12) & 0x03; |
| 89 | if (rx_cmd != 0) |
| 90 | printf("mclink_send: received cmd %d, expected %d\n", rx_cmd, |
| 91 | 0); |
| 92 | |
| 93 | return 0; |
| 94 | } |
| 95 | |
| 96 | int mclink_receive(u8 slave, u16 addr, u16 *data) |
| 97 | { |
| 98 | u16 rx_cmd_status; |
| 99 | u16 rx_cmd; |
| 100 | u16 int_status; |
| 101 | unsigned int ctr = 0; |
| 102 | |
| 103 | /* send read request */ |
| 104 | FPGA_SET_REG(0, mc_tx_address, addr); |
| 105 | FPGA_SET_REG(0, mc_tx_cmd, |
| 106 | ((slave & 0x03) << 14) | (1 << 12) | (1 << 0)); |
| 107 | FPGA_SET_REG(0, mc_control, 0x8001); |
| 108 | |
| 109 | |
| 110 | /* wait for reply */ |
| 111 | FPGA_GET_REG(0, mc_int, &int_status); |
| 112 | while (!(int_status & MCINT_RX_CONTENT_AVAILABLE)) { |
| 113 | udelay(100); |
| 114 | if (ctr++ > 3) |
| 115 | return -ETIMEDOUT; |
| 116 | FPGA_GET_REG(0, mc_int, &int_status); |
| 117 | } |
| 118 | |
| 119 | /* check reply */ |
| 120 | FPGA_GET_REG(0, mc_rx_cmd_status, &rx_cmd_status); |
| 121 | if ((rx_cmd_status >> 14) != slave) { |
| 122 | printf("mclink_receive: reply from slave %d, expected %d\n", |
| 123 | rx_cmd_status >> 14, slave); |
| 124 | return -EINVAL; |
| 125 | } |
| 126 | |
| 127 | rx_cmd = (rx_cmd_status >> 12) & 0x03; |
| 128 | if (rx_cmd != 1) { |
| 129 | printf("mclink_send: received cmd %d, expected %d\n", |
| 130 | rx_cmd, 1); |
| 131 | return -EIO; |
| 132 | } |
| 133 | |
| 134 | FPGA_GET_REG(0, mc_rx_data, data); |
| 135 | |
| 136 | return 0; |
| 137 | } |