1 // SPDX-License-Identifier: GPL-2.0
3  * System Control and Management Interface (SCMI) Message Mailbox Transport
6  * Copyright (C) 2019-2024 ARM Ltd.
20  * struct scmi_mailbox - Structure representing a SCMI mailbox transport
23  * @chan: Transmit/Receive mailbox uni/bi-directional channel
48 	core->shmem->tx_prepare(smbox->shmem, m, smbox->cinfo);  in tx_prepare()
61 	 * a previous timed-out reply which arrived late could be wrongly  in rx_callback()
64 	if (cl->knows_txdone &&  in rx_callback()
65 	    !core->shmem->channel_free(smbox->shmem)) {  in rx_callback()
66 		dev_warn(smbox->cinfo->dev, "Ignoring spurious A2P IRQ !\n");  in rx_callback()
67 		core->bad_message_trace(smbox->cinfo,  in rx_callback()
68 			     core->shmem->read_header(smbox->shmem),  in rx_callback()
73 	core->rx_callback(smbox->cinfo,  in rx_callback()
74 		      core->shmem->read_header(smbox->shmem), NULL);  in rx_callback()
86 	num_mb = of_count_phandle_with_args(of_node, "mboxes", "#mbox-cells");  in mailbox_chan_available()
91 					   "#mbox-cells", idx, NULL);  in mailbox_chan_available()
95  * mailbox_chan_validate  - Validate transport configuration and map channels
101  * @p2a_chan: A reference to the optional p2a channel.
103  * @p2a_rx_chan: A reference to the optional p2a completion channel.
116 	struct device_node *np = cdev->of_node;  in mailbox_chan_validate()
118 	num_mb = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");  in mailbox_chan_validate()
127 			 "Invalid channel descriptor for '%s' - mbs:%d  shm:%d\n",  in mailbox_chan_validate()
129 		return -EINVAL;  in mailbox_chan_validate()
142 			ret = -EINVAL;  in mailbox_chan_validate()
184 	struct device *cdev = cinfo->dev;  in mailbox_chan_setup()
194 		return -ENODEV;  in mailbox_chan_setup()
198 		return -ENOMEM;  in mailbox_chan_setup()
200 	smbox->shmem = core->shmem->setup_iomap(cinfo, dev, tx, NULL);  in mailbox_chan_setup()
201 	if (IS_ERR(smbox->shmem))  in mailbox_chan_setup()
202 		return PTR_ERR(smbox->shmem);  in mailbox_chan_setup()
204 	cl = &smbox->cl;  in mailbox_chan_setup()
205 	cl->dev = cdev;  in mailbox_chan_setup()
206 	cl->tx_prepare = tx ? tx_prepare : NULL;  in mailbox_chan_setup()
207 	cl->rx_callback = rx_callback;  in mailbox_chan_setup()
208 	cl->tx_block = false;  in mailbox_chan_setup()
209 	cl->knows_txdone = tx;  in mailbox_chan_setup()
211 	smbox->chan = mbox_request_channel(cl, tx ? 0 : p2a_chan);  in mailbox_chan_setup()
212 	if (IS_ERR(smbox->chan)) {  in mailbox_chan_setup()
213 		ret = PTR_ERR(smbox->chan);  in mailbox_chan_setup()
214 		if (ret != -EPROBE_DEFER)  in mailbox_chan_setup()
222 		smbox->chan_receiver = mbox_request_channel(cl, a2p_rx_chan);  in mailbox_chan_setup()
223 		if (IS_ERR(smbox->chan_receiver)) {  in mailbox_chan_setup()
224 			ret = PTR_ERR(smbox->chan_receiver);  in mailbox_chan_setup()
225 			if (ret != -EPROBE_DEFER)  in mailbox_chan_setup()
232 		smbox->chan_platform_receiver = mbox_request_channel(cl, p2a_rx_chan);  in mailbox_chan_setup()
233 		if (IS_ERR(smbox->chan_platform_receiver)) {  in mailbox_chan_setup()
234 			ret = PTR_ERR(smbox->chan_platform_receiver);  in mailbox_chan_setup()
235 			if (ret != -EPROBE_DEFER)  in mailbox_chan_setup()
236 				dev_err(cdev, "failed to request SCMI P2A Receiver mailbox\n");  in mailbox_chan_setup()
241 	cinfo->transport_info = smbox;  in mailbox_chan_setup()
242 	smbox->cinfo = cinfo;  in mailbox_chan_setup()
243 	mutex_init(&smbox->chan_lock);  in mailbox_chan_setup()
251 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_chan_free()
253 	if (smbox && !IS_ERR(smbox->chan)) {  in mailbox_chan_free()
254 		mbox_free_channel(smbox->chan);  in mailbox_chan_free()
255 		mbox_free_channel(smbox->chan_receiver);  in mailbox_chan_free()
256 		mbox_free_channel(smbox->chan_platform_receiver);  in mailbox_chan_free()
257 		cinfo->transport_info = NULL;  in mailbox_chan_free()
258 		smbox->chan = NULL;  in mailbox_chan_free()
259 		smbox->chan_receiver = NULL;  in mailbox_chan_free()
260 		smbox->chan_platform_receiver = NULL;  in mailbox_chan_free()
261 		smbox->cinfo = NULL;  in mailbox_chan_free()
270 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_send_message()
280 	mutex_lock(&smbox->chan_lock);  in mailbox_send_message()
282 	ret = mbox_send_message(smbox->chan, xfer);  in mailbox_send_message()
283 	/* mbox_send_message returns non-negative value on success */  in mailbox_send_message()
285 		mutex_unlock(&smbox->chan_lock);  in mailbox_send_message()
295 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_mark_txdone()
297 	mbox_client_txdone(smbox->chan, ret);  in mailbox_mark_txdone()
300 	mutex_unlock(&smbox->chan_lock);  in mailbox_mark_txdone()
306 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_fetch_response()
308 	core->shmem->fetch_response(smbox->shmem, xfer);  in mailbox_fetch_response()
314 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_fetch_notification()
316 	core->shmem->fetch_notification(smbox->shmem, max_len, xfer);  in mailbox_fetch_notification()
321 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_clear_channel()
325 	core->shmem->clear_channel(smbox->shmem);  in mailbox_clear_channel()
327 	if (!core->shmem->channel_intr_enabled(smbox->shmem))  in mailbox_clear_channel()
330 	if (smbox->chan_platform_receiver)  in mailbox_clear_channel()
331 		intr_chan = smbox->chan_platform_receiver;  in mailbox_clear_channel()
332 	else if (smbox->chan)  in mailbox_clear_channel()
333 		intr_chan = smbox->chan;  in mailbox_clear_channel()
338 	/* mbox_send_message returns non-negative value on success, so reset */  in mailbox_clear_channel()
348 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_poll_done()
350 	return core->shmem->poll_done(smbox->shmem, xfer);  in mailbox_poll_done()