1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Intel SST generic IPC Support 4 * 5 * Copyright (C) 2015, Intel Corporation. All rights reserved. 6 */ 7 8 #include <linux/types.h> 9 #include <linux/kernel.h> 10 #include <linux/list.h> 11 #include <linux/wait.h> 12 #include <linux/module.h> 13 #include <linux/spinlock.h> 14 #include <linux/device.h> 15 #include <linux/slab.h> 16 #include <linux/workqueue.h> 17 #include <linux/sched.h> 18 #include <linux/delay.h> 19 #include <linux/platform_device.h> 20 #include <sound/asound.h> 21 22 #include "sst-dsp.h" 23 #include "sst-dsp-priv.h" 24 #include "sst-ipc.h" 25 26 /* IPC message timeout (msecs) */ 27 #define IPC_TIMEOUT_MSECS 300 28 29 #define IPC_EMPTY_LIST_SIZE 8 30 31 /* locks held by caller */ 32 static struct ipc_message *msg_get_empty(struct sst_generic_ipc *ipc) 33 { 34 struct ipc_message *msg = NULL; 35 36 if (!list_empty(&ipc->empty_list)) { 37 msg = list_first_entry(&ipc->empty_list, struct ipc_message, 38 list); 39 list_del(&msg->list); 40 } 41 42 return msg; 43 } 44 45 static int tx_wait_done(struct sst_generic_ipc *ipc, 46 struct ipc_message *msg, struct sst_ipc_message *reply) 47 { 48 unsigned long flags; 49 int ret; 50 51 /* wait for DSP completion (in all cases atm inc pending) */ 52 ret = wait_event_timeout(msg->waitq, msg->complete, 53 msecs_to_jiffies(IPC_TIMEOUT_MSECS)); 54 55 spin_lock_irqsave(&ipc->dsp->spinlock, flags); 56 if (ret == 0) { 57 if (ipc->ops.shim_dbg != NULL) 58 ipc->ops.shim_dbg(ipc, "message timeout"); 59 60 list_del(&msg->list); 61 ret = -ETIMEDOUT; 62 } else { 63 64 /* copy the data returned from DSP */ 65 if (reply) { 66 reply->header = msg->rx.header; 67 if (reply->data) 68 memcpy(reply->data, msg->rx.data, msg->rx.size); 69 } 70 ret = msg->errno; 71 } 72 73 list_add_tail(&msg->list, &ipc->empty_list); 74 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags); 75 return ret; 76 } 77 78 static int ipc_tx_message(struct sst_generic_ipc *ipc, 79 struct sst_ipc_message request, 80 struct sst_ipc_message *reply, int wait) 81 { 82 struct ipc_message *msg; 83 unsigned long flags; 84 85 spin_lock_irqsave(&ipc->dsp->spinlock, flags); 86 87 msg = msg_get_empty(ipc); 88 if (msg == NULL) { 89 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags); 90 return -EBUSY; 91 } 92 93 msg->tx.header = request.header; 94 msg->tx.size = request.size; 95 msg->rx.header = 0; 96 msg->rx.size = reply ? reply->size : 0; 97 msg->wait = wait; 98 msg->errno = 0; 99 msg->pending = false; 100 msg->complete = false; 101 102 if ((request.size) && (ipc->ops.tx_data_copy != NULL)) 103 ipc->ops.tx_data_copy(msg, request.data, request.size); 104 105 list_add_tail(&msg->list, &ipc->tx_list); 106 schedule_work(&ipc->kwork); 107 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags); 108 109 if (wait) 110 return tx_wait_done(ipc, msg, reply); 111 else 112 return 0; 113 } 114 115 static int msg_empty_list_init(struct sst_generic_ipc *ipc) 116 { 117 int i; 118 119 ipc->msg = kcalloc(IPC_EMPTY_LIST_SIZE, sizeof(struct ipc_message), 120 GFP_KERNEL); 121 if (ipc->msg == NULL) 122 return -ENOMEM; 123 124 for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) { 125 ipc->msg[i].tx.data = kzalloc(ipc->tx_data_max_size, GFP_KERNEL); 126 if (ipc->msg[i].tx.data == NULL) 127 goto free_mem; 128 129 ipc->msg[i].rx.data = kzalloc(ipc->rx_data_max_size, GFP_KERNEL); 130 if (ipc->msg[i].rx.data == NULL) { 131 kfree(ipc->msg[i].tx.data); 132 goto free_mem; 133 } 134 135 init_waitqueue_head(&ipc->msg[i].waitq); 136 list_add(&ipc->msg[i].list, &ipc->empty_list); 137 } 138 139 return 0; 140 141 free_mem: 142 while (i > 0) { 143 kfree(ipc->msg[i-1].tx.data); 144 kfree(ipc->msg[i-1].rx.data); 145 --i; 146 } 147 kfree(ipc->msg); 148 149 return -ENOMEM; 150 } 151 152 static void ipc_tx_msgs(struct work_struct *work) 153 { 154 struct sst_generic_ipc *ipc = 155 container_of(work, struct sst_generic_ipc, kwork); 156 struct ipc_message *msg; 157 158 spin_lock_irq(&ipc->dsp->spinlock); 159 160 while (!list_empty(&ipc->tx_list) && !ipc->pending) { 161 /* if the DSP is busy, we will TX messages after IRQ. 162 * also postpone if we are in the middle of processing 163 * completion irq 164 */ 165 if (ipc->ops.is_dsp_busy && ipc->ops.is_dsp_busy(ipc->dsp)) { 166 dev_dbg(ipc->dev, "ipc_tx_msgs dsp busy\n"); 167 break; 168 } 169 170 msg = list_first_entry(&ipc->tx_list, struct ipc_message, list); 171 list_move(&msg->list, &ipc->rx_list); 172 173 if (ipc->ops.tx_msg != NULL) 174 ipc->ops.tx_msg(ipc, msg); 175 } 176 177 spin_unlock_irq(&ipc->dsp->spinlock); 178 } 179 180 int sst_ipc_tx_message_wait(struct sst_generic_ipc *ipc, 181 struct sst_ipc_message request, struct sst_ipc_message *reply) 182 { 183 int ret; 184 185 /* 186 * DSP maybe in lower power active state, so 187 * check if the DSP supports DSP lp On method 188 * if so invoke that before sending IPC 189 */ 190 if (ipc->ops.check_dsp_lp_on) 191 if (ipc->ops.check_dsp_lp_on(ipc->dsp, true)) 192 return -EIO; 193 194 ret = ipc_tx_message(ipc, request, reply, 1); 195 196 if (ipc->ops.check_dsp_lp_on) 197 if (ipc->ops.check_dsp_lp_on(ipc->dsp, false)) 198 return -EIO; 199 200 return ret; 201 } 202 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_wait); 203 204 int sst_ipc_tx_message_nowait(struct sst_generic_ipc *ipc, 205 struct sst_ipc_message request) 206 { 207 return ipc_tx_message(ipc, request, NULL, 0); 208 } 209 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_nowait); 210 211 int sst_ipc_tx_message_nopm(struct sst_generic_ipc *ipc, 212 struct sst_ipc_message request, struct sst_ipc_message *reply) 213 { 214 return ipc_tx_message(ipc, request, reply, 1); 215 } 216 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_nopm); 217 218 struct ipc_message *sst_ipc_reply_find_msg(struct sst_generic_ipc *ipc, 219 u64 header) 220 { 221 struct ipc_message *msg; 222 u64 mask; 223 224 if (ipc->ops.reply_msg_match != NULL) 225 header = ipc->ops.reply_msg_match(header, &mask); 226 else 227 mask = (u64)-1; 228 229 if (list_empty(&ipc->rx_list)) { 230 dev_err(ipc->dev, "error: rx list empty but received 0x%llx\n", 231 header); 232 return NULL; 233 } 234 235 list_for_each_entry(msg, &ipc->rx_list, list) { 236 if ((msg->tx.header & mask) == header) 237 return msg; 238 } 239 240 return NULL; 241 } 242 EXPORT_SYMBOL_GPL(sst_ipc_reply_find_msg); 243 244 /* locks held by caller */ 245 void sst_ipc_tx_msg_reply_complete(struct sst_generic_ipc *ipc, 246 struct ipc_message *msg) 247 { 248 msg->complete = true; 249 250 if (!msg->wait) 251 list_add_tail(&msg->list, &ipc->empty_list); 252 else 253 wake_up(&msg->waitq); 254 } 255 EXPORT_SYMBOL_GPL(sst_ipc_tx_msg_reply_complete); 256 257 void sst_ipc_drop_all(struct sst_generic_ipc *ipc) 258 { 259 struct ipc_message *msg, *tmp; 260 unsigned long flags; 261 int tx_drop_cnt = 0, rx_drop_cnt = 0; 262 263 /* drop all TX and Rx messages before we stall + reset DSP */ 264 spin_lock_irqsave(&ipc->dsp->spinlock, flags); 265 266 list_for_each_entry_safe(msg, tmp, &ipc->tx_list, list) { 267 list_move(&msg->list, &ipc->empty_list); 268 tx_drop_cnt++; 269 } 270 271 list_for_each_entry_safe(msg, tmp, &ipc->rx_list, list) { 272 list_move(&msg->list, &ipc->empty_list); 273 rx_drop_cnt++; 274 } 275 276 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags); 277 278 if (tx_drop_cnt || rx_drop_cnt) 279 dev_err(ipc->dev, "dropped IPC msg RX=%d, TX=%d\n", 280 tx_drop_cnt, rx_drop_cnt); 281 } 282 EXPORT_SYMBOL_GPL(sst_ipc_drop_all); 283 284 int sst_ipc_init(struct sst_generic_ipc *ipc) 285 { 286 int ret; 287 288 INIT_LIST_HEAD(&ipc->tx_list); 289 INIT_LIST_HEAD(&ipc->rx_list); 290 INIT_LIST_HEAD(&ipc->empty_list); 291 init_waitqueue_head(&ipc->wait_txq); 292 293 ret = msg_empty_list_init(ipc); 294 if (ret < 0) 295 return -ENOMEM; 296 297 INIT_WORK(&ipc->kwork, ipc_tx_msgs); 298 return 0; 299 } 300 EXPORT_SYMBOL_GPL(sst_ipc_init); 301 302 void sst_ipc_fini(struct sst_generic_ipc *ipc) 303 { 304 int i; 305 306 cancel_work_sync(&ipc->kwork); 307 308 if (ipc->msg) { 309 for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) { 310 kfree(ipc->msg[i].tx.data); 311 kfree(ipc->msg[i].rx.data); 312 } 313 kfree(ipc->msg); 314 } 315 } 316 EXPORT_SYMBOL_GPL(sst_ipc_fini); 317 318 /* Module information */ 319 MODULE_AUTHOR("Jin Yao"); 320 MODULE_DESCRIPTION("Intel SST IPC generic"); 321 MODULE_LICENSE("GPL v2"); 322