1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright (c) 2016-2017 Hisilicon Limited.
3 
4 #include "hclge_mbx.h"
5 #include "hclgevf_main.h"
6 #include "hnae3.h"
7 
8 static void hclgevf_reset_mbx_resp_status(struct hclgevf_dev *hdev)
9 {
10 	/* this function should be called with mbx_resp.mbx_mutex held
11 	 * to prtect the received_response from race condition
12 	 */
13 	hdev->mbx_resp.received_resp  = false;
14 	hdev->mbx_resp.origin_mbx_msg = 0;
15 	hdev->mbx_resp.resp_status    = 0;
16 	memset(hdev->mbx_resp.additional_info, 0, HCLGE_MBX_MAX_RESP_DATA_SIZE);
17 }
18 
19 /* hclgevf_get_mbx_resp: used to get a response from PF after VF sends a mailbox
20  * message to PF.
21  * @hdev: pointer to struct hclgevf_dev
22  * @resp_msg: pointer to store the original message type and response status
23  * @len: the resp_msg data array length.
24  */
25 static int hclgevf_get_mbx_resp(struct hclgevf_dev *hdev, u16 code0, u16 code1,
26 				u8 *resp_data, u16 resp_len)
27 {
28 #define HCLGEVF_MAX_TRY_TIMES	500
29 #define HCLGEVF_SLEEP_USCOEND	1000
30 	struct hclgevf_mbx_resp_status *mbx_resp;
31 	u16 r_code0, r_code1;
32 	int i = 0;
33 
34 	if (resp_len > HCLGE_MBX_MAX_RESP_DATA_SIZE) {
35 		dev_err(&hdev->pdev->dev,
36 			"VF mbx response len(=%d) exceeds maximum(=%d)\n",
37 			resp_len,
38 			HCLGE_MBX_MAX_RESP_DATA_SIZE);
39 		return -EINVAL;
40 	}
41 
42 	while ((!hdev->mbx_resp.received_resp) && (i < HCLGEVF_MAX_TRY_TIMES)) {
43 		udelay(HCLGEVF_SLEEP_USCOEND);
44 		i++;
45 	}
46 
47 	if (i >= HCLGEVF_MAX_TRY_TIMES) {
48 		dev_err(&hdev->pdev->dev,
49 			"VF could not get mbx resp(=%d) from PF in %d tries\n",
50 			hdev->mbx_resp.received_resp, i);
51 		return -EIO;
52 	}
53 
54 	mbx_resp = &hdev->mbx_resp;
55 	r_code0 = (u16)(mbx_resp->origin_mbx_msg >> 16);
56 	r_code1 = (u16)(mbx_resp->origin_mbx_msg & 0xff);
57 
58 	if (mbx_resp->resp_status)
59 		return mbx_resp->resp_status;
60 
61 	if (resp_data)
62 		memcpy(resp_data, &mbx_resp->additional_info[0], resp_len);
63 
64 	hclgevf_reset_mbx_resp_status(hdev);
65 
66 	if (!(r_code0 == code0 && r_code1 == code1 && !mbx_resp->resp_status)) {
67 		dev_err(&hdev->pdev->dev,
68 			"VF could not match resp code(code0=%d,code1=%d), %d",
69 			code0, code1, mbx_resp->resp_status);
70 		return -EIO;
71 	}
72 
73 	return 0;
74 }
75 
76 int hclgevf_send_mbx_msg(struct hclgevf_dev *hdev, u16 code, u16 subcode,
77 			 const u8 *msg_data, u8 msg_len, bool need_resp,
78 			 u8 *resp_data, u16 resp_len)
79 {
80 	struct hclge_mbx_vf_to_pf_cmd *req;
81 	struct hclgevf_desc desc;
82 	int status;
83 
84 	req = (struct hclge_mbx_vf_to_pf_cmd *)desc.data;
85 
86 	/* first two bytes are reserved for code & subcode */
87 	if (msg_len > (HCLGE_MBX_MAX_MSG_SIZE - 2)) {
88 		dev_err(&hdev->pdev->dev,
89 			"VF send mbx msg fail, msg len %d exceeds max len %d\n",
90 			msg_len, HCLGE_MBX_MAX_MSG_SIZE);
91 		return -EINVAL;
92 	}
93 
94 	hclgevf_cmd_setup_basic_desc(&desc, HCLGEVF_OPC_MBX_VF_TO_PF, false);
95 	req->msg[0] = code;
96 	req->msg[1] = subcode;
97 	memcpy(&req->msg[2], msg_data, msg_len);
98 
99 	/* synchronous send */
100 	if (need_resp) {
101 		mutex_lock(&hdev->mbx_resp.mbx_mutex);
102 		hclgevf_reset_mbx_resp_status(hdev);
103 		status = hclgevf_cmd_send(&hdev->hw, &desc, 1);
104 		if (status) {
105 			dev_err(&hdev->pdev->dev,
106 				"VF failed(=%d) to send mbx message to PF\n",
107 				status);
108 			mutex_unlock(&hdev->mbx_resp.mbx_mutex);
109 			return status;
110 		}
111 
112 		status = hclgevf_get_mbx_resp(hdev, code, subcode, resp_data,
113 					      resp_len);
114 		mutex_unlock(&hdev->mbx_resp.mbx_mutex);
115 	} else {
116 		/* asynchronous send */
117 		status = hclgevf_cmd_send(&hdev->hw, &desc, 1);
118 		if (status) {
119 			dev_err(&hdev->pdev->dev,
120 				"VF failed(=%d) to send mbx message to PF\n",
121 				status);
122 			return status;
123 		}
124 	}
125 
126 	return status;
127 }
128 
129 static bool hclgevf_cmd_crq_empty(struct hclgevf_hw *hw)
130 {
131 	u32 tail = hclgevf_read_dev(hw, HCLGEVF_NIC_CRQ_TAIL_REG);
132 
133 	return tail == hw->cmq.crq.next_to_use;
134 }
135 
136 void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
137 {
138 	struct hclgevf_mbx_resp_status *resp;
139 	struct hclge_mbx_pf_to_vf_cmd *req;
140 	struct hclgevf_cmq_ring *crq;
141 	struct hclgevf_desc *desc;
142 	u16 *msg_q;
143 	u16 flag;
144 	u8 *temp;
145 	int i;
146 
147 	resp = &hdev->mbx_resp;
148 	crq = &hdev->hw.cmq.crq;
149 
150 	while (!hclgevf_cmd_crq_empty(&hdev->hw)) {
151 		desc = &crq->desc[crq->next_to_use];
152 		req = (struct hclge_mbx_pf_to_vf_cmd *)desc->data;
153 
154 		flag = le16_to_cpu(crq->desc[crq->next_to_use].flag);
155 		if (unlikely(!hnae3_get_bit(flag, HCLGEVF_CMDQ_RX_OUTVLD_B))) {
156 			dev_warn(&hdev->pdev->dev,
157 				 "dropped invalid mailbox message, code = %d\n",
158 				 req->msg[0]);
159 
160 			/* dropping/not processing this invalid message */
161 			crq->desc[crq->next_to_use].flag = 0;
162 			hclge_mbx_ring_ptr_move_crq(crq);
163 			continue;
164 		}
165 
166 		/* synchronous messages are time critical and need preferential
167 		 * treatment. Therefore, we need to acknowledge all the sync
168 		 * responses as quickly as possible so that waiting tasks do not
169 		 * timeout and simultaneously queue the async messages for later
170 		 * prcessing in context of mailbox task i.e. the slow path.
171 		 */
172 		switch (req->msg[0]) {
173 		case HCLGE_MBX_PF_VF_RESP:
174 			if (resp->received_resp)
175 				dev_warn(&hdev->pdev->dev,
176 					 "VF mbx resp flag not clear(%d)\n",
177 					 req->msg[1]);
178 			resp->received_resp = true;
179 
180 			resp->origin_mbx_msg = (req->msg[1] << 16);
181 			resp->origin_mbx_msg |= req->msg[2];
182 			resp->resp_status = req->msg[3];
183 
184 			temp = (u8 *)&req->msg[4];
185 			for (i = 0; i < HCLGE_MBX_MAX_RESP_DATA_SIZE; i++) {
186 				resp->additional_info[i] = *temp;
187 				temp++;
188 			}
189 			break;
190 		case HCLGE_MBX_LINK_STAT_CHANGE:
191 		case HCLGE_MBX_ASSERTING_RESET:
192 			/* set this mbx event as pending. This is required as we
193 			 * might loose interrupt event when mbx task is busy
194 			 * handling. This shall be cleared when mbx task just
195 			 * enters handling state.
196 			 */
197 			hdev->mbx_event_pending = true;
198 
199 			/* we will drop the async msg if we find ARQ as full
200 			 * and continue with next message
201 			 */
202 			if (hdev->arq.count >= HCLGE_MBX_MAX_ARQ_MSG_NUM) {
203 				dev_warn(&hdev->pdev->dev,
204 					 "Async Q full, dropping msg(%d)\n",
205 					 req->msg[1]);
206 				break;
207 			}
208 
209 			/* tail the async message in arq */
210 			msg_q = hdev->arq.msg_q[hdev->arq.tail];
211 			memcpy(&msg_q[0], req->msg,
212 			       HCLGE_MBX_MAX_ARQ_MSG_SIZE * sizeof(u16));
213 			hclge_mbx_tail_ptr_move_arq(hdev->arq);
214 			hdev->arq.count++;
215 
216 			hclgevf_mbx_task_schedule(hdev);
217 
218 			break;
219 		default:
220 			dev_err(&hdev->pdev->dev,
221 				"VF received unsupported(%d) mbx msg from PF\n",
222 				req->msg[0]);
223 			break;
224 		}
225 		crq->desc[crq->next_to_use].flag = 0;
226 		hclge_mbx_ring_ptr_move_crq(crq);
227 	}
228 
229 	/* Write back CMDQ_RQ header pointer, M7 need this pointer */
230 	hclgevf_write_dev(&hdev->hw, HCLGEVF_NIC_CRQ_HEAD_REG,
231 			  crq->next_to_use);
232 }
233 
234 void hclgevf_mbx_async_handler(struct hclgevf_dev *hdev)
235 {
236 	u16 link_status;
237 	u16 *msg_q;
238 	u8 duplex;
239 	u32 speed;
240 	u32 tail;
241 
242 	/* we can safely clear it now as we are at start of the async message
243 	 * processing
244 	 */
245 	hdev->mbx_event_pending = false;
246 
247 	tail = hdev->arq.tail;
248 
249 	/* process all the async queue messages */
250 	while (tail != hdev->arq.head) {
251 		msg_q = hdev->arq.msg_q[hdev->arq.head];
252 
253 		switch (msg_q[0]) {
254 		case HCLGE_MBX_LINK_STAT_CHANGE:
255 			link_status = le16_to_cpu(msg_q[1]);
256 			memcpy(&speed, &msg_q[2], sizeof(speed));
257 			duplex = (u8)le16_to_cpu(msg_q[4]);
258 
259 			/* update upper layer with new link link status */
260 			hclgevf_update_link_status(hdev, link_status);
261 			hclgevf_update_speed_duplex(hdev, speed, duplex);
262 
263 			break;
264 		case HCLGE_MBX_ASSERTING_RESET:
265 			/* PF has asserted reset hence VF should go in pending
266 			 * state and poll for the hardware reset status till it
267 			 * has been completely reset. After this stack should
268 			 * eventually be re-initialized.
269 			 */
270 			hdev->nic.reset_level = HNAE3_VF_RESET;
271 			set_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state);
272 			hclgevf_reset_task_schedule(hdev);
273 
274 			break;
275 		default:
276 			dev_err(&hdev->pdev->dev,
277 				"fetched unsupported(%d) message from arq\n",
278 				msg_q[0]);
279 			break;
280 		}
281 
282 		hclge_mbx_head_ptr_move_arq(hdev->arq);
283 		hdev->arq.count--;
284 		msg_q = hdev->arq.msg_q[hdev->arq.head];
285 	}
286 }
287