sound/soc/intel/common/sst-ipc.c

   1 /*
   2  * Intel SST generic IPC Support
   3  *
   4  * Copyright (C) 2015, Intel Corporation. All rights reserved.
   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 version
   8  * 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16
  17 #include <linux/types.h>
  18 #include <linux/kernel.h>
  19 #include <linux/list.h>
  20 #include <linux/wait.h>
  21 #include <linux/module.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/device.h>
  24 #include <linux/slab.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/sched.h>
  27 #include <linux/delay.h>
  28 #include <linux/platform_device.h>
  29 #include <sound/asound.h>
  30
  31 #include "sst-dsp.h"
  32 #include "sst-dsp-priv.h"
  33 #include "sst-ipc.h"
  34
  35 /* IPC message timeout (msecs) */
  36 #define IPC_TIMEOUT_MSECS       300
  37
  38 #define IPC_EMPTY_LIST_SIZE     8
  39
  40 /* locks held by caller */
  41 static struct ipc_message *msg_get_empty(struct sst_generic_ipc *ipc)
  42 {
  43         struct ipc_message *msg = NULL;
  44
  45         if (!list_empty(&ipc->empty_list)) {
  46                 msg = list_first_entry(&ipc->empty_list, struct ipc_message,
  47                         list);
  48                 list_del(&msg->list);
  49         }
  50
  51         return msg;
  52 }
  53
  54 static int tx_wait_done(struct sst_generic_ipc *ipc,
  55         struct ipc_message *msg, void *rx_data)
  56 {
  57         unsigned long flags;
  58         int ret;
  59
  60         /* wait for DSP completion (in all cases atm inc pending) */
  61         ret = wait_event_timeout(msg->waitq, msg->complete,
  62                 msecs_to_jiffies(IPC_TIMEOUT_MSECS));
  63
  64         spin_lock_irqsave(&ipc->dsp->spinlock, flags);
  65         if (ret == 0) {
  66                 if (ipc->ops.shim_dbg != NULL)
  67                         ipc->ops.shim_dbg(ipc, "message timeout");
  68
  69                 list_del(&msg->list);
  70                 ret = -ETIMEDOUT;
  71         } else {
  72
  73                 /* copy the data returned from DSP */
  74                 if (msg->rx_size)
  75                         memcpy(rx_data, msg->rx_data, msg->rx_size);
  76                 ret = msg->errno;
  77         }
  78
  79         list_add_tail(&msg->list, &ipc->empty_list);
  80         spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
  81         return ret;
  82 }
  83
  84 static int ipc_tx_message(struct sst_generic_ipc *ipc, u64 header,
  85         void *tx_data, size_t tx_bytes, void *rx_data,
  86         size_t rx_bytes, int wait)
  87 {
  88         struct ipc_message *msg;
  89         unsigned long flags;
  90
  91         spin_lock_irqsave(&ipc->dsp->spinlock, flags);
  92
  93         msg = msg_get_empty(ipc);
  94         if (msg == NULL) {
  95                 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
  96                 return -EBUSY;
  97         }
  98
  99         msg->header = header;
 100         msg->tx_size = tx_bytes;
 101         msg->rx_size = rx_bytes;
 102         msg->wait = wait;
 103         msg->errno = 0;
 104         msg->pending = false;
 105         msg->complete = false;
 106
 107         if ((tx_bytes) && (ipc->ops.tx_data_copy != NULL))
 108                 ipc->ops.tx_data_copy(msg, tx_data, tx_bytes);
 109
 110         list_add_tail(&msg->list, &ipc->tx_list);
 111         schedule_work(&ipc->kwork);
 112         spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
 113
 114         if (wait)
 115                 return tx_wait_done(ipc, msg, rx_data);
 116         else
 117                 return 0;
 118 }
 119
 120 static int msg_empty_list_init(struct sst_generic_ipc *ipc)
 121 {
 122         int i;
 123
 124         ipc->msg = kzalloc(sizeof(struct ipc_message) *
 125                 IPC_EMPTY_LIST_SIZE, GFP_KERNEL);
 126         if (ipc->msg == NULL)
 127                 return -ENOMEM;
 128
 129         for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) {
 130                 ipc->msg[i].tx_data = kzalloc(ipc->tx_data_max_size, GFP_KERNEL);
 131                 if (ipc->msg[i].tx_data == NULL)
 132                         goto free_mem;
 133
 134                 ipc->msg[i].rx_data = kzalloc(ipc->rx_data_max_size, GFP_KERNEL);
 135                 if (ipc->msg[i].rx_data == NULL) {
 136                         kfree(ipc->msg[i].tx_data);
 137                         goto free_mem;
 138                 }
 139
 140                 init_waitqueue_head(&ipc->msg[i].waitq);
 141                 list_add(&ipc->msg[i].list, &ipc->empty_list);
 142         }
 143
 144         return 0;
 145
 146 free_mem:
 147         while (i > 0) {
 148                 kfree(ipc->msg[i-1].tx_data);
 149                 kfree(ipc->msg[i-1].rx_data);
 150                 --i;
 151         }
 152         kfree(ipc->msg);
 153
 154         return -ENOMEM;
 155 }
 156
 157 static void ipc_tx_msgs(struct work_struct *work)
 158 {
 159         struct sst_generic_ipc *ipc =
 160                 container_of(work, struct sst_generic_ipc, kwork);
 161         struct ipc_message *msg;
 162
 163         spin_lock_irq(&ipc->dsp->spinlock);
 164
 165         while (!list_empty(&ipc->tx_list) && !ipc->pending) {
 166                 /* if the DSP is busy, we will TX messages after IRQ.
 167                  * also postpone if we are in the middle of processing
 168                  * completion irq
 169                  */
 170                 if (ipc->ops.is_dsp_busy && ipc->ops.is_dsp_busy(ipc->dsp)) {
 171                         dev_dbg(ipc->dev, "ipc_tx_msgs dsp busy\n");
 172                         break;
 173                 }
 174
 175                 msg = list_first_entry(&ipc->tx_list, struct ipc_message, list);
 176                 list_move(&msg->list, &ipc->rx_list);
 177
 178                 if (ipc->ops.tx_msg != NULL)
 179                         ipc->ops.tx_msg(ipc, msg);
 180         }
 181
 182         spin_unlock_irq(&ipc->dsp->spinlock);
 183 }
 184
 185 int sst_ipc_tx_message_wait(struct sst_generic_ipc *ipc, u64 header,
 186         void *tx_data, size_t tx_bytes, void *rx_data, size_t rx_bytes)
 187 {
 188         int ret;
 189
 190         /*
 191          * DSP maybe in lower power active state, so
 192          * check if the DSP supports DSP lp On method
 193          * if so invoke that before sending IPC
 194          */
 195         if (ipc->ops.check_dsp_lp_on)
 196                 if (ipc->ops.check_dsp_lp_on(ipc->dsp, true))
 197                         return -EIO;
 198
 199         ret = ipc_tx_message(ipc, header, tx_data, tx_bytes,
 200                 rx_data, rx_bytes, 1);
 201
 202         if (ipc->ops.check_dsp_lp_on)
 203                 if (ipc->ops.check_dsp_lp_on(ipc->dsp, false))
 204                         return -EIO;
 205
 206         return ret;
 207 }
 208 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_wait);
 209
 210 int sst_ipc_tx_message_nowait(struct sst_generic_ipc *ipc, u64 header,
 211         void *tx_data, size_t tx_bytes)
 212 {
 213         return ipc_tx_message(ipc, header, tx_data, tx_bytes,
 214                 NULL, 0, 0);
 215 }
 216 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_nowait);
 217
 218 int sst_ipc_tx_message_nopm(struct sst_generic_ipc *ipc, u64 header,
 219         void *tx_data, size_t tx_bytes, void *rx_data, size_t rx_bytes)
 220 {
 221         return ipc_tx_message(ipc, header, tx_data, tx_bytes,
 222                 rx_data, rx_bytes, 1);
 223 }
 224 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_nopm);
 225
 226 struct ipc_message *sst_ipc_reply_find_msg(struct sst_generic_ipc *ipc,
 227         u64 header)
 228 {
 229         struct ipc_message *msg;
 230         u64 mask;
 231
 232         if (ipc->ops.reply_msg_match != NULL)
 233                 header = ipc->ops.reply_msg_match(header, &mask);
 234
 235         if (list_empty(&ipc->rx_list)) {
 236                 dev_err(ipc->dev, "error: rx list empty but received 0x%llx\n",
 237                         header);
 238                 return NULL;
 239         }
 240
 241         list_for_each_entry(msg, &ipc->rx_list, list) {
 242                 if ((msg->header & mask) == header)
 243                         return msg;
 244         }
 245
 246         return NULL;
 247 }
 248 EXPORT_SYMBOL_GPL(sst_ipc_reply_find_msg);
 249
 250 /* locks held by caller */
 251 void sst_ipc_tx_msg_reply_complete(struct sst_generic_ipc *ipc,
 252         struct ipc_message *msg)
 253 {
 254         msg->complete = true;
 255
 256         if (!msg->wait)
 257                 list_add_tail(&msg->list, &ipc->empty_list);
 258         else
 259                 wake_up(&msg->waitq);
 260 }
 261 EXPORT_SYMBOL_GPL(sst_ipc_tx_msg_reply_complete);
 262
 263 void sst_ipc_drop_all(struct sst_generic_ipc *ipc)
 264 {
 265         struct ipc_message *msg, *tmp;
 266         unsigned long flags;
 267         int tx_drop_cnt = 0, rx_drop_cnt = 0;
 268
 269         /* drop all TX and Rx messages before we stall + reset DSP */
 270         spin_lock_irqsave(&ipc->dsp->spinlock, flags);
 271
 272         list_for_each_entry_safe(msg, tmp, &ipc->tx_list, list) {
 273                 list_move(&msg->list, &ipc->empty_list);
 274                 tx_drop_cnt++;
 275         }
 276
 277         list_for_each_entry_safe(msg, tmp, &ipc->rx_list, list) {
 278                 list_move(&msg->list, &ipc->empty_list);
 279                 rx_drop_cnt++;
 280         }
 281
 282         spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
 283
 284         if (tx_drop_cnt || rx_drop_cnt)
 285                 dev_err(ipc->dev, "dropped IPC msg RX=%d, TX=%d\n",
 286                         tx_drop_cnt, rx_drop_cnt);
 287 }
 288 EXPORT_SYMBOL_GPL(sst_ipc_drop_all);
 289
 290 int sst_ipc_init(struct sst_generic_ipc *ipc)
 291 {
 292         int ret;
 293
 294         INIT_LIST_HEAD(&ipc->tx_list);
 295         INIT_LIST_HEAD(&ipc->rx_list);
 296         INIT_LIST_HEAD(&ipc->empty_list);
 297         init_waitqueue_head(&ipc->wait_txq);
 298
 299         ret = msg_empty_list_init(ipc);
 300         if (ret < 0)
 301                 return -ENOMEM;
 302
 303         INIT_WORK(&ipc->kwork, ipc_tx_msgs);
 304         return 0;
 305 }
 306 EXPORT_SYMBOL_GPL(sst_ipc_init);
 307
 308 void sst_ipc_fini(struct sst_generic_ipc *ipc)
 309 {
 310         int i;
 311
 312         cancel_work_sync(&ipc->kwork);
 313
 314         if (ipc->msg) {
 315                 for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) {
 316                         kfree(ipc->msg[i].tx_data);
 317                         kfree(ipc->msg[i].rx_data);
 318                 }
 319                 kfree(ipc->msg);
 320         }
 321 }
 322 EXPORT_SYMBOL_GPL(sst_ipc_fini);
 323
 324 /* Module information */
 325 MODULE_AUTHOR("Jin Yao");
 326 MODULE_DESCRIPTION("Intel SST IPC generic");
 327 MODULE_LICENSE("GPL v2");