Nico Huber | 7bb0251 | 2013-05-23 16:35:05 +0200 | [diff] [blame] | 1 | /* |
| 2 | * This file is part of the coreboot project. |
| 3 | * |
| 4 | * Copyright (C) 2013 secunet Security Networks AG |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License as |
| 8 | * published by the Free Software Foundation; version 2 of |
| 9 | * the License. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
Nico Huber | 7bb0251 | 2013-05-23 16:35:05 +0200 | [diff] [blame] | 15 | */ |
| 16 | |
| 17 | /* |
| 18 | * ACPI style embedded controller commands |
| 19 | * |
| 20 | * Controlled by the following preprocessor defines: |
| 21 | * EC_SC_IO I/o address of the EC_SC register |
| 22 | * EC_DATA_IO I/o address of the EC_DATA register |
| 23 | */ |
| 24 | |
| 25 | #define EC_MUTEX ECMX |
| 26 | #define WAIT_EC_SC WECC |
| 27 | #define SEND_EC_COMMAND SECC |
| 28 | #define SEND_EC_DATA SECD |
| 29 | #define RECV_EC_DATA RECD |
| 30 | #define EC_READ ECRD |
| 31 | #define EC_WRITE ECWR |
| 32 | #define EC_SC ECSC |
| 33 | #define EC_DATA ECDT |
| 34 | |
| 35 | #define EC_OBF 0x01 /* Output buffer full (EC_DATA) */ |
| 36 | #define EC_IBF 0x02 /* Input buffer full (EC_DATA or EC_SC) */ |
| 37 | |
| 38 | #define EC_ERROR_MASK 0xff00 |
| 39 | #define EC_TIMEOUT 0x8000 |
| 40 | |
| 41 | #define EC_READ_CMD 0x80 |
| 42 | #define EC_WRITE_CMD 0x81 |
| 43 | |
| 44 | Mutex(EC_MUTEX, 1) |
| 45 | |
| 46 | OperationRegion(ERSC, SystemIO, EC_SC_IO, 1) |
| 47 | Field(ERSC, ByteAcc, NoLock, Preserve) { EC_SC, 8 } |
| 48 | OperationRegion(ERDT, SystemIO, EC_DATA_IO, 1) |
| 49 | Field(ERDT, ByteAcc, NoLock, Preserve) { EC_DATA, 8 } |
| 50 | |
| 51 | /* |
| 52 | * Wait for a bit in the status and command (EC_SC) register |
| 53 | * |
| 54 | * The caller is responsible of acquiring the EC_MUTEX before |
| 55 | * calling this method. |
| 56 | * |
| 57 | * Arg0: Mask, Arg1: State waiting for |
| 58 | * Returns EC_TIMEOUT if timed out, 0 else |
| 59 | */ |
| 60 | Method (WAIT_EC_SC, 2) |
| 61 | { |
| 62 | Store (0x7ff, Local0) /* Timeout */ |
| 63 | While (LAnd (LNotEqual (And (EC_SC, Arg0), Arg1), Decrement (Local0))) { |
| 64 | Stall (10) |
| 65 | } |
| 66 | If (Local0) { |
| 67 | Return (0) |
| 68 | } Else { |
| 69 | Return (EC_TIMEOUT) |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | /* |
| 74 | * Send command byte in Arg0 to status and command (EC_SC) register |
| 75 | * |
| 76 | * The caller is responsible of acquiring the EC_MUTEX before |
| 77 | * calling this method. |
| 78 | * |
| 79 | * Returns EC_TIMEOUT if timed out, 0 else |
| 80 | */ |
| 81 | Method (SEND_EC_COMMAND, 1) |
| 82 | { |
| 83 | Store (WAIT_EC_SC (EC_IBF, 0), Local0) |
| 84 | If (LNot (Local0)) { |
| 85 | Store (Arg0, EC_SC) |
| 86 | } |
| 87 | Return (Local0) |
| 88 | } |
| 89 | |
| 90 | /* |
| 91 | * Send data byte in Arg0 to data (EC_DATA) register |
| 92 | * |
| 93 | * The caller is responsible of acquiring the EC_MUTEX before |
| 94 | * calling this method. |
| 95 | * |
| 96 | * Returns EC_TIMEOUT if timed out, 0 else |
| 97 | */ |
| 98 | Method (SEND_EC_DATA, 1) |
| 99 | { |
| 100 | Store (WAIT_EC_SC (EC_IBF, 0), Local0) |
| 101 | If (LNot (Local0)) { |
| 102 | Store (Arg0, EC_DATA) |
| 103 | } |
| 104 | Return (Local0) |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Read one byte of data from data (EC_DATA) register |
| 109 | * |
| 110 | * The caller is responsible of acquiring the EC_MUTEX before |
| 111 | * calling this method. |
| 112 | * |
| 113 | * Returns EC_TIMEOUT if timed out, the read data byte else |
| 114 | */ |
| 115 | Method (RECV_EC_DATA) |
| 116 | { |
| 117 | Store (WAIT_EC_SC (EC_OBF, EC_OBF), Local0) |
| 118 | If (LNot (Local0)) { |
| 119 | Return (EC_DATA) |
| 120 | } Else { |
| 121 | Return (Local0) |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | /* |
| 126 | * Read one byte from ec memory (cmd 0x80) |
| 127 | * |
| 128 | * Arg0: Address (1 byte) to read from |
| 129 | * Returns EC_TIMEOUT if timed out, the read data byte else |
| 130 | */ |
| 131 | Method (EC_READ, 1) |
| 132 | { |
| 133 | Acquire (EC_MUTEX, 0xffff) |
| 134 | Store (SEND_EC_COMMAND (EC_READ_CMD), Local0) |
| 135 | If (LNot (Local0)) { |
| 136 | Store (SEND_EC_DATA (Arg0), Local0) |
| 137 | } |
| 138 | If (LNot (Local0)) { |
| 139 | Store (RECV_EC_DATA (), Local0) |
| 140 | } |
| 141 | Release (EC_MUTEX) |
| 142 | |
| 143 | Return (Local0) |
| 144 | } |
| 145 | |
| 146 | /* |
| 147 | * Write one byte to ec memory (cmd 0x81) |
| 148 | * |
| 149 | * Arg0: Address (1 byte) to write to |
| 150 | * Arg1: Byte to write |
| 151 | * Returns EC_TIMEOUT if timed out, 0 else |
| 152 | */ |
| 153 | Method (EC_WRITE, 2) |
| 154 | { |
| 155 | Acquire (EC_MUTEX, 0xffff) |
| 156 | Store (SEND_EC_COMMAND (EC_WRITE_CMD), Local0) |
| 157 | If (LNot (Local0)) { |
| 158 | Store (SEND_EC_DATA (Arg0), Local0) |
| 159 | } |
| 160 | If (LNot (Local0)) { |
| 161 | Store (SEND_EC_DATA (Arg1), Local0) |
| 162 | } |
| 163 | Release (EC_MUTEX) |
| 164 | |
| 165 | Return (Local0) |
| 166 | } |