xref: /openbmc/linux/drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_mbx.c (revision b240b419db5d624ce7a5a397d6f62a1a686009ec)
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 void hclgevf_mbx_handler(struct hclgevf_dev *hdev)
130 {
131 	struct hclgevf_mbx_resp_status *resp;
132 	struct hclge_mbx_pf_to_vf_cmd *req;
133 	struct hclgevf_cmq_ring *crq;
134 	struct hclgevf_desc *desc;
135 	u16 *msg_q;
136 	u16 flag;
137 	u8 *temp;
138 	int i;
139 
140 	resp = &hdev->mbx_resp;
141 	crq = &hdev->hw.cmq.crq;
142 
143 	flag = le16_to_cpu(crq->desc[crq->next_to_use].flag);
144 	while (hnae_get_bit(flag, HCLGEVF_CMDQ_RX_OUTVLD_B)) {
145 		desc = &crq->desc[crq->next_to_use];
146 		req = (struct hclge_mbx_pf_to_vf_cmd *)desc->data;
147 
148 		/* synchronous messages are time critical and need preferential
149 		 * treatment. Therefore, we need to acknowledge all the sync
150 		 * responses as quickly as possible so that waiting tasks do not
151 		 * timeout and simultaneously queue the async messages for later
152 		 * prcessing in context of mailbox task i.e. the slow path.
153 		 */
154 		switch (req->msg[0]) {
155 		case HCLGE_MBX_PF_VF_RESP:
156 			if (resp->received_resp)
157 				dev_warn(&hdev->pdev->dev,
158 					 "VF mbx resp flag not clear(%d)\n",
159 					 req->msg[1]);
160 			resp->received_resp = true;
161 
162 			resp->origin_mbx_msg = (req->msg[1] << 16);
163 			resp->origin_mbx_msg |= req->msg[2];
164 			resp->resp_status = req->msg[3];
165 
166 			temp = (u8 *)&req->msg[4];
167 			for (i = 0; i < HCLGE_MBX_MAX_RESP_DATA_SIZE; i++) {
168 				resp->additional_info[i] = *temp;
169 				temp++;
170 			}
171 			break;
172 		case HCLGE_MBX_LINK_STAT_CHANGE:
173 		case HCLGE_MBX_ASSERTING_RESET:
174 			/* set this mbx event as pending. This is required as we
175 			 * might loose interrupt event when mbx task is busy
176 			 * handling. This shall be cleared when mbx task just
177 			 * enters handling state.
178 			 */
179 			hdev->mbx_event_pending = true;
180 
181 			/* we will drop the async msg if we find ARQ as full
182 			 * and continue with next message
183 			 */
184 			if (hdev->arq.count >= HCLGE_MBX_MAX_ARQ_MSG_NUM) {
185 				dev_warn(&hdev->pdev->dev,
186 					 "Async Q full, dropping msg(%d)\n",
187 					 req->msg[1]);
188 				break;
189 			}
190 
191 			/* tail the async message in arq */
192 			msg_q = hdev->arq.msg_q[hdev->arq.tail];
193 			memcpy(&msg_q[0], req->msg, HCLGE_MBX_MAX_ARQ_MSG_SIZE);
194 			hclge_mbx_tail_ptr_move_arq(hdev->arq);
195 			hdev->arq.count++;
196 
197 			hclgevf_mbx_task_schedule(hdev);
198 
199 			break;
200 		default:
201 			dev_err(&hdev->pdev->dev,
202 				"VF received unsupported(%d) mbx msg from PF\n",
203 				req->msg[0]);
204 			break;
205 		}
206 		crq->desc[crq->next_to_use].flag = 0;
207 		hclge_mbx_ring_ptr_move_crq(crq);
208 		flag = le16_to_cpu(crq->desc[crq->next_to_use].flag);
209 	}
210 
211 	/* Write back CMDQ_RQ header pointer, M7 need this pointer */
212 	hclgevf_write_dev(&hdev->hw, HCLGEVF_NIC_CRQ_HEAD_REG,
213 			  crq->next_to_use);
214 }
215 
216 void hclgevf_mbx_async_handler(struct hclgevf_dev *hdev)
217 {
218 	u16 link_status;
219 	u16 *msg_q;
220 	u8 duplex;
221 	u32 speed;
222 	u32 tail;
223 
224 	/* we can safely clear it now as we are at start of the async message
225 	 * processing
226 	 */
227 	hdev->mbx_event_pending = false;
228 
229 	tail = hdev->arq.tail;
230 
231 	/* process all the async queue messages */
232 	while (tail != hdev->arq.head) {
233 		msg_q = hdev->arq.msg_q[hdev->arq.head];
234 
235 		switch (msg_q[0]) {
236 		case HCLGE_MBX_LINK_STAT_CHANGE:
237 			link_status = le16_to_cpu(msg_q[1]);
238 			memcpy(&speed, &msg_q[2], sizeof(speed));
239 			duplex = (u8)le16_to_cpu(msg_q[4]);
240 
241 			/* update upper layer with new link link status */
242 			hclgevf_update_link_status(hdev, link_status);
243 			hclgevf_update_speed_duplex(hdev, speed, duplex);
244 
245 			break;
246 		case HCLGE_MBX_ASSERTING_RESET:
247 			/* PF has asserted reset hence VF should go in pending
248 			 * state and poll for the hardware reset status till it
249 			 * has been completely reset. After this stack should
250 			 * eventually be re-initialized.
251 			 */
252 			hdev->nic.reset_level = HNAE3_VF_RESET;
253 			set_bit(HCLGEVF_RESET_PENDING, &hdev->reset_state);
254 			hclgevf_reset_task_schedule(hdev);
255 
256 			break;
257 		default:
258 			dev_err(&hdev->pdev->dev,
259 				"fetched unsupported(%d) message from arq\n",
260 				msg_q[0]);
261 			break;
262 		}
263 
264 		hclge_mbx_head_ptr_move_arq(hdev->arq);
265 		hdev->arq.count--;
266 		msg_q = hdev->arq.msg_q[hdev->arq.head];
267 	}
268 }
269