2 * Intel SST generic IPC Support
4 * Copyright (C) 2015, Intel Corporation. All rights reserved.
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.
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.
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 <linux/kthread.h>
30 #include <sound/asound.h>
33 #include "sst-dsp-priv.h"
36 /* IPC message timeout (msecs) */
37 #define IPC_TIMEOUT_MSECS 300
39 #define IPC_EMPTY_LIST_SIZE 8
41 /* locks held by caller */
42 static struct ipc_message *msg_get_empty(struct sst_generic_ipc *ipc)
44 struct ipc_message *msg = NULL;
46 if (!list_empty(&ipc->empty_list)) {
47 msg = list_first_entry(&ipc->empty_list, struct ipc_message,
55 static int tx_wait_done(struct sst_generic_ipc *ipc,
56 struct ipc_message *msg, void *rx_data)
61 /* wait for DSP completion (in all cases atm inc pending) */
62 ret = wait_event_timeout(msg->waitq, msg->complete,
63 msecs_to_jiffies(IPC_TIMEOUT_MSECS));
65 spin_lock_irqsave(&ipc->dsp->spinlock, flags);
67 if (ipc->ops.shim_dbg != NULL)
68 ipc->ops.shim_dbg(ipc, "message timeout");
74 /* copy the data returned from DSP */
76 memcpy(rx_data, msg->rx_data, msg->rx_size);
80 list_add_tail(&msg->list, &ipc->empty_list);
81 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
85 static int ipc_tx_message(struct sst_generic_ipc *ipc, u64 header,
86 void *tx_data, size_t tx_bytes, void *rx_data,
87 size_t rx_bytes, int wait)
89 struct ipc_message *msg;
92 spin_lock_irqsave(&ipc->dsp->spinlock, flags);
94 msg = msg_get_empty(ipc);
96 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
100 msg->header = header;
101 msg->tx_size = tx_bytes;
102 msg->rx_size = rx_bytes;
105 msg->pending = false;
106 msg->complete = false;
108 if ((tx_bytes) && (ipc->ops.tx_data_copy != NULL))
109 ipc->ops.tx_data_copy(msg, tx_data, tx_bytes);
111 list_add_tail(&msg->list, &ipc->tx_list);
112 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
114 queue_kthread_work(&ipc->kworker, &ipc->kwork);
117 return tx_wait_done(ipc, msg, rx_data);
122 static int msg_empty_list_init(struct sst_generic_ipc *ipc)
126 ipc->msg = kzalloc(sizeof(struct ipc_message) *
127 IPC_EMPTY_LIST_SIZE, GFP_KERNEL);
128 if (ipc->msg == NULL)
131 for (i = 0; i < IPC_EMPTY_LIST_SIZE; i++) {
132 init_waitqueue_head(&ipc->msg[i].waitq);
133 list_add(&ipc->msg[i].list, &ipc->empty_list);
139 static void ipc_tx_msgs(struct kthread_work *work)
141 struct sst_generic_ipc *ipc =
142 container_of(work, struct sst_generic_ipc, kwork);
143 struct ipc_message *msg;
147 spin_lock_irqsave(&ipc->dsp->spinlock, flags);
149 if (list_empty(&ipc->tx_list) || ipc->pending) {
150 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
154 /* if the DSP is busy, we will TX messages after IRQ.
155 * also postpone if we are in the middle of procesing completion irq*/
156 ipcx = sst_dsp_shim_read_unlocked(ipc->dsp, SST_IPCX);
157 if (ipcx & (SST_IPCX_BUSY | SST_IPCX_DONE)) {
158 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
162 msg = list_first_entry(&ipc->tx_list, struct ipc_message, list);
163 list_move(&msg->list, &ipc->rx_list);
165 if (ipc->ops.tx_msg != NULL)
166 ipc->ops.tx_msg(ipc, msg);
168 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
171 int sst_ipc_tx_message_wait(struct sst_generic_ipc *ipc, u64 header,
172 void *tx_data, size_t tx_bytes, void *rx_data, size_t rx_bytes)
174 return ipc_tx_message(ipc, header, tx_data, tx_bytes,
175 rx_data, rx_bytes, 1);
177 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_wait);
179 int sst_ipc_tx_message_nowait(struct sst_generic_ipc *ipc, u64 header,
180 void *tx_data, size_t tx_bytes)
182 return ipc_tx_message(ipc, header, tx_data, tx_bytes,
185 EXPORT_SYMBOL_GPL(sst_ipc_tx_message_nowait);
187 struct ipc_message *sst_ipc_reply_find_msg(struct sst_generic_ipc *ipc,
190 struct ipc_message *msg;
193 if (ipc->ops.reply_msg_match != NULL)
194 header = ipc->ops.reply_msg_match(header, &mask);
196 if (list_empty(&ipc->rx_list)) {
197 dev_err(ipc->dev, "error: rx list empty but received 0x%llx\n",
202 list_for_each_entry(msg, &ipc->rx_list, list) {
203 if ((msg->header & mask) == header)
209 EXPORT_SYMBOL_GPL(sst_ipc_reply_find_msg);
211 /* locks held by caller */
212 void sst_ipc_tx_msg_reply_complete(struct sst_generic_ipc *ipc,
213 struct ipc_message *msg)
215 msg->complete = true;
218 list_add_tail(&msg->list, &ipc->empty_list);
220 wake_up(&msg->waitq);
222 EXPORT_SYMBOL_GPL(sst_ipc_tx_msg_reply_complete);
224 void sst_ipc_drop_all(struct sst_generic_ipc *ipc)
226 struct ipc_message *msg, *tmp;
228 int tx_drop_cnt = 0, rx_drop_cnt = 0;
230 /* drop all TX and Rx messages before we stall + reset DSP */
231 spin_lock_irqsave(&ipc->dsp->spinlock, flags);
233 list_for_each_entry_safe(msg, tmp, &ipc->tx_list, list) {
234 list_move(&msg->list, &ipc->empty_list);
238 list_for_each_entry_safe(msg, tmp, &ipc->rx_list, list) {
239 list_move(&msg->list, &ipc->empty_list);
243 spin_unlock_irqrestore(&ipc->dsp->spinlock, flags);
245 if (tx_drop_cnt || rx_drop_cnt)
246 dev_err(ipc->dev, "dropped IPC msg RX=%d, TX=%d\n",
247 tx_drop_cnt, rx_drop_cnt);
249 EXPORT_SYMBOL_GPL(sst_ipc_drop_all);
251 int sst_ipc_init(struct sst_generic_ipc *ipc)
255 INIT_LIST_HEAD(&ipc->tx_list);
256 INIT_LIST_HEAD(&ipc->rx_list);
257 INIT_LIST_HEAD(&ipc->empty_list);
258 init_waitqueue_head(&ipc->wait_txq);
260 ret = msg_empty_list_init(ipc);
264 /* start the IPC message thread */
265 init_kthread_worker(&ipc->kworker);
266 ipc->tx_thread = kthread_run(kthread_worker_fn,
269 if (IS_ERR(ipc->tx_thread)) {
270 dev_err(ipc->dev, "error: failed to create message TX task\n");
271 ret = PTR_ERR(ipc->tx_thread);
276 init_kthread_work(&ipc->kwork, ipc_tx_msgs);
279 EXPORT_SYMBOL_GPL(sst_ipc_init);
281 void sst_ipc_fini(struct sst_generic_ipc *ipc)
284 kthread_stop(ipc->tx_thread);
289 EXPORT_SYMBOL_GPL(sst_ipc_fini);
291 /* Module information */
292 MODULE_AUTHOR("Jin Yao");
293 MODULE_DESCRIPTION("Intel SST IPC generic");
294 MODULE_LICENSE("GPL v2");