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

   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 int sst_ipc_init(struct sst_generic_ipc *ipc)
 258 {
 259         int ret;
 260
 261         INIT_LIST_HEAD(&ipc->tx_list);
 262         INIT_LIST_HEAD(&ipc->rx_list);
 263         INIT_LIST_HEAD(&ipc->empty_list);
 264         init_waitqueue_head(&ipc->wait_txq);
 265
 266         ret = msg_empty_list_init(ipc);
 267         if (ret < 0)
 268                 return -ENOMEM;
 269
 270         INIT_WORK(&ipc->kwork, ipc_tx_msgs);
 271         return 0;
 272 }
 273 EXPORT_SYMBOL_GPL(sst_ipc_init);
 274
 275 void sst_ipc_fini(struct sst_generic_ipc *ipc)
 276 {
 277         int i;
 278
 279         cancel_work_sync(&ipc->kwork);
 280
 281         if (ipc->msg) {
 282                 for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) {
 283                         kfree(ipc->msg[i].tx.data);
 284                         kfree(ipc->msg[i].rx.data);
 285                 }
 286                 kfree(ipc->msg);
 287         }
 288 }
 289 EXPORT_SYMBOL_GPL(sst_ipc_fini);
 290
 291 /* Module information */
 292 MODULE_AUTHOR("Jin Yao");
 293 MODULE_DESCRIPTION("Intel SST IPC generic");
 294 MODULE_LICENSE("GPL v2");