1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2020-21 Intel Corporation.
4  */
5 
6 #include "iosm_ipc_imem.h"
7 #include "iosm_ipc_protocol.h"
8 #include "iosm_ipc_protocol_ops.h"
9 #include "iosm_ipc_pm.h"
10 #include "iosm_ipc_task_queue.h"
11 
12 int ipc_protocol_tq_msg_send(struct iosm_protocol *ipc_protocol,
13 			     enum ipc_msg_prep_type msg_type,
14 			     union ipc_msg_prep_args *prep_args,
15 			     struct ipc_rsp *response)
16 {
17 	int index = ipc_protocol_msg_prep(ipc_protocol->imem, msg_type,
18 					  prep_args);
19 
20 	/* Store reference towards caller specified response in response ring
21 	 * and signal CP
22 	 */
23 	if (index >= 0 && index < IPC_MEM_MSG_ENTRIES) {
24 		ipc_protocol->rsp_ring[index] = response;
25 		ipc_protocol_msg_hp_update(ipc_protocol->imem);
26 	}
27 
28 	return index;
29 }
30 
31 /* Callback for message send */
32 static int ipc_protocol_tq_msg_send_cb(struct iosm_imem *ipc_imem, int arg,
33 				       void *msg, size_t size)
34 {
35 	struct ipc_call_msg_send_args *send_args = msg;
36 	struct iosm_protocol *ipc_protocol = ipc_imem->ipc_protocol;
37 
38 	return ipc_protocol_tq_msg_send(ipc_protocol, send_args->msg_type,
39 					send_args->prep_args,
40 					send_args->response);
41 }
42 
43 /* Remove reference to a response. This is typically used when a requestor timed
44  * out and is no longer interested in the response.
45  */
46 static int ipc_protocol_tq_msg_remove(struct iosm_imem *ipc_imem, int arg,
47 				      void *msg, size_t size)
48 {
49 	struct iosm_protocol *ipc_protocol = ipc_imem->ipc_protocol;
50 
51 	ipc_protocol->rsp_ring[arg] = NULL;
52 	return 0;
53 }
54 
55 int ipc_protocol_msg_send(struct iosm_protocol *ipc_protocol,
56 			  enum ipc_msg_prep_type prep,
57 			  union ipc_msg_prep_args *prep_args)
58 {
59 	struct ipc_call_msg_send_args send_args;
60 	unsigned int exec_timeout;
61 	struct ipc_rsp response;
62 	int index;
63 
64 	exec_timeout = (ipc_protocol_get_ap_exec_stage(ipc_protocol) ==
65 					IPC_MEM_EXEC_STAGE_RUN ?
66 				IPC_MSG_COMPLETE_RUN_DEFAULT_TIMEOUT :
67 				IPC_MSG_COMPLETE_BOOT_DEFAULT_TIMEOUT);
68 
69 	/* Trap if called from non-preemptible context */
70 	might_sleep();
71 
72 	response.status = IPC_MEM_MSG_CS_INVALID;
73 	init_completion(&response.completion);
74 
75 	send_args.msg_type = prep;
76 	send_args.prep_args = prep_args;
77 	send_args.response = &response;
78 
79 	/* Allocate and prepare message to be sent in tasklet context.
80 	 * A positive index returned form tasklet_call references the message
81 	 * in case it needs to be cancelled when there is a timeout.
82 	 */
83 	index = ipc_task_queue_send_task(ipc_protocol->imem,
84 					 ipc_protocol_tq_msg_send_cb, 0,
85 					 &send_args, 0, true);
86 
87 	if (index < 0) {
88 		dev_err(ipc_protocol->dev, "msg %d failed", prep);
89 		return index;
90 	}
91 
92 	/* Wait for the device to respond to the message */
93 	switch (wait_for_completion_timeout(&response.completion,
94 					    msecs_to_jiffies(exec_timeout))) {
95 	case 0:
96 		/* Timeout, there was no response from the device.
97 		 * Remove the reference to the local response completion
98 		 * object as we are no longer interested in the response.
99 		 */
100 		ipc_task_queue_send_task(ipc_protocol->imem,
101 					 ipc_protocol_tq_msg_remove, index,
102 					 NULL, 0, true);
103 		dev_err(ipc_protocol->dev, "msg timeout");
104 		ipc_uevent_send(ipc_protocol->pcie->dev, UEVENT_MDM_TIMEOUT);
105 		break;
106 	default:
107 		/* We got a response in time; check completion status: */
108 		if (response.status != IPC_MEM_MSG_CS_SUCCESS) {
109 			dev_err(ipc_protocol->dev,
110 				"msg completion status error %d",
111 				response.status);
112 			return -EIO;
113 		}
114 	}
115 
116 	return 0;
117 }
118 
119 static int ipc_protocol_msg_send_host_sleep(struct iosm_protocol *ipc_protocol,
120 					    u32 state)
121 {
122 	union ipc_msg_prep_args prep_args = {
123 		.sleep.target = 0,
124 		.sleep.state = state,
125 	};
126 
127 	return ipc_protocol_msg_send(ipc_protocol, IPC_MSG_PREP_SLEEP,
128 				     &prep_args);
129 }
130 
131 void ipc_protocol_doorbell_trigger(struct iosm_protocol *ipc_protocol,
132 				   u32 identifier)
133 {
134 	ipc_pm_signal_hpda_doorbell(&ipc_protocol->pm, identifier, true);
135 }
136 
137 bool ipc_protocol_pm_dev_sleep_handle(struct iosm_protocol *ipc_protocol)
138 {
139 	u32 ipc_status = ipc_protocol_get_ipc_status(ipc_protocol);
140 	u32 requested;
141 
142 	if (ipc_status != IPC_MEM_DEVICE_IPC_RUNNING) {
143 		dev_err(ipc_protocol->dev,
144 			"irq ignored, CP IPC state is %d, should be RUNNING",
145 			ipc_status);
146 
147 		/* Stop further processing. */
148 		return false;
149 	}
150 
151 	/* Get a copy of the requested PM state by the device and the local
152 	 * device PM state.
153 	 */
154 	requested = ipc_protocol_pm_dev_get_sleep_notification(ipc_protocol);
155 
156 	return ipc_pm_dev_slp_notification(&ipc_protocol->pm, requested);
157 }
158 
159 static int ipc_protocol_tq_wakeup_dev_slp(struct iosm_imem *ipc_imem, int arg,
160 					  void *msg, size_t size)
161 {
162 	struct iosm_pm *ipc_pm = &ipc_imem->ipc_protocol->pm;
163 
164 	/* Wakeup from device sleep if it is not ACTIVE */
165 	ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_HS, true);
166 
167 	ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_HS, false);
168 
169 	return 0;
170 }
171 
172 void ipc_protocol_s2idle_sleep(struct iosm_protocol *ipc_protocol, bool sleep)
173 {
174 	ipc_pm_set_s2idle_sleep(&ipc_protocol->pm, sleep);
175 }
176 
177 bool ipc_protocol_suspend(struct iosm_protocol *ipc_protocol)
178 {
179 	if (!ipc_pm_prepare_host_sleep(&ipc_protocol->pm))
180 		goto err;
181 
182 	ipc_task_queue_send_task(ipc_protocol->imem,
183 				 ipc_protocol_tq_wakeup_dev_slp, 0, NULL, 0,
184 				 true);
185 
186 	if (!ipc_pm_wait_for_device_active(&ipc_protocol->pm)) {
187 		ipc_uevent_send(ipc_protocol->pcie->dev, UEVENT_MDM_TIMEOUT);
188 		goto err;
189 	}
190 
191 	/* Send the sleep message for sync sys calls. */
192 	dev_dbg(ipc_protocol->dev, "send TARGET_HOST, ENTER_SLEEP");
193 	if (ipc_protocol_msg_send_host_sleep(ipc_protocol,
194 					     IPC_HOST_SLEEP_ENTER_SLEEP)) {
195 		/* Sending ENTER_SLEEP message failed, we are still active */
196 		ipc_protocol->pm.host_pm_state = IPC_MEM_HOST_PM_ACTIVE;
197 		goto err;
198 	}
199 
200 	ipc_protocol->pm.host_pm_state = IPC_MEM_HOST_PM_SLEEP;
201 	return true;
202 err:
203 	return false;
204 }
205 
206 bool ipc_protocol_resume(struct iosm_protocol *ipc_protocol)
207 {
208 	if (!ipc_pm_prepare_host_active(&ipc_protocol->pm))
209 		return false;
210 
211 	dev_dbg(ipc_protocol->dev, "send TARGET_HOST, EXIT_SLEEP");
212 	if (ipc_protocol_msg_send_host_sleep(ipc_protocol,
213 					     IPC_HOST_SLEEP_EXIT_SLEEP)) {
214 		ipc_protocol->pm.host_pm_state = IPC_MEM_HOST_PM_SLEEP;
215 		return false;
216 	}
217 
218 	ipc_protocol->pm.host_pm_state = IPC_MEM_HOST_PM_ACTIVE;
219 
220 	return true;
221 }
222 
223 struct iosm_protocol *ipc_protocol_init(struct iosm_imem *ipc_imem)
224 {
225 	struct iosm_protocol *ipc_protocol =
226 		kzalloc(sizeof(*ipc_protocol), GFP_KERNEL);
227 	struct ipc_protocol_context_info *p_ci;
228 	u64 addr;
229 
230 	if (!ipc_protocol)
231 		return NULL;
232 
233 	ipc_protocol->dev = ipc_imem->dev;
234 	ipc_protocol->pcie = ipc_imem->pcie;
235 	ipc_protocol->imem = ipc_imem;
236 	ipc_protocol->p_ap_shm = NULL;
237 	ipc_protocol->phy_ap_shm = 0;
238 
239 	ipc_protocol->old_msg_tail = 0;
240 
241 	ipc_protocol->p_ap_shm =
242 		pci_alloc_consistent(ipc_protocol->pcie->pci,
243 				     sizeof(*ipc_protocol->p_ap_shm),
244 				     &ipc_protocol->phy_ap_shm);
245 
246 	if (!ipc_protocol->p_ap_shm) {
247 		dev_err(ipc_protocol->dev, "pci shm alloc error");
248 		kfree(ipc_protocol);
249 		return NULL;
250 	}
251 
252 	/* Prepare the context info for CP. */
253 	addr = ipc_protocol->phy_ap_shm;
254 	p_ci = &ipc_protocol->p_ap_shm->ci;
255 	p_ci->device_info_addr =
256 		addr + offsetof(struct ipc_protocol_ap_shm, device_info);
257 	p_ci->head_array =
258 		addr + offsetof(struct ipc_protocol_ap_shm, head_array);
259 	p_ci->tail_array =
260 		addr + offsetof(struct ipc_protocol_ap_shm, tail_array);
261 	p_ci->msg_head = addr + offsetof(struct ipc_protocol_ap_shm, msg_head);
262 	p_ci->msg_tail = addr + offsetof(struct ipc_protocol_ap_shm, msg_tail);
263 	p_ci->msg_ring_addr =
264 		addr + offsetof(struct ipc_protocol_ap_shm, msg_ring);
265 	p_ci->msg_ring_entries = cpu_to_le16(IPC_MEM_MSG_ENTRIES);
266 	p_ci->msg_irq_vector = IPC_MSG_IRQ_VECTOR;
267 	p_ci->device_info_irq_vector = IPC_DEVICE_IRQ_VECTOR;
268 
269 	ipc_mmio_set_contex_info_addr(ipc_imem->mmio, addr);
270 
271 	ipc_pm_init(ipc_protocol);
272 
273 	return ipc_protocol;
274 }
275 
276 void ipc_protocol_deinit(struct iosm_protocol *proto)
277 {
278 	pci_free_consistent(proto->pcie->pci, sizeof(*proto->p_ap_shm),
279 			    proto->p_ap_shm, proto->phy_ap_shm);
280 
281 	ipc_pm_deinit(proto);
282 	kfree(proto);
283 }
284