1 /*
2  * Copyright (c) 2007 Cisco Systems, Inc. All rights reserved.
3  * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include <linux/workqueue.h>
35 #include <linux/module.h>
36 
37 #include "mlx4.h"
38 
39 enum {
40 	MLX4_CATAS_POLL_INTERVAL	= 5 * HZ,
41 };
42 
43 
44 
45 int mlx4_internal_err_reset = 1;
46 module_param_named(internal_err_reset, mlx4_internal_err_reset,  int, 0644);
47 MODULE_PARM_DESC(internal_err_reset,
48 		 "Reset device on internal errors if non-zero (default 1)");
49 
50 static int read_vendor_id(struct mlx4_dev *dev)
51 {
52 	u16 vendor_id = 0;
53 	int ret;
54 
55 	ret = pci_read_config_word(dev->persist->pdev, 0, &vendor_id);
56 	if (ret) {
57 		mlx4_err(dev, "Failed to read vendor ID, ret=%d\n", ret);
58 		return ret;
59 	}
60 
61 	if (vendor_id == 0xffff) {
62 		mlx4_err(dev, "PCI can't be accessed to read vendor id\n");
63 		return -EINVAL;
64 	}
65 
66 	return 0;
67 }
68 
69 static int mlx4_reset_master(struct mlx4_dev *dev)
70 {
71 	int err = 0;
72 
73 	if (mlx4_is_master(dev))
74 		mlx4_report_internal_err_comm_event(dev);
75 
76 	if (!pci_channel_offline(dev->persist->pdev)) {
77 		err = read_vendor_id(dev);
78 		/* If PCI can't be accessed to read vendor ID we assume that its
79 		 * link was disabled and chip was already reset.
80 		 */
81 		if (err)
82 			return 0;
83 
84 		err = mlx4_reset(dev);
85 		if (err)
86 			mlx4_err(dev, "Fail to reset HCA\n");
87 	}
88 
89 	return err;
90 }
91 
92 static int mlx4_reset_slave(struct mlx4_dev *dev)
93 {
94 #define COM_CHAN_RST_REQ_OFFSET 0x10
95 #define COM_CHAN_RST_ACK_OFFSET 0x08
96 
97 	u32 comm_flags;
98 	u32 rst_req;
99 	u32 rst_ack;
100 	unsigned long end;
101 	struct mlx4_priv *priv = mlx4_priv(dev);
102 
103 	if (pci_channel_offline(dev->persist->pdev))
104 		return 0;
105 
106 	comm_flags = swab32(readl((__iomem char *)priv->mfunc.comm +
107 				  MLX4_COMM_CHAN_FLAGS));
108 	if (comm_flags == 0xffffffff) {
109 		mlx4_err(dev, "VF reset is not needed\n");
110 		return 0;
111 	}
112 
113 	if (!(dev->caps.vf_caps & MLX4_VF_CAP_FLAG_RESET)) {
114 		mlx4_err(dev, "VF reset is not supported\n");
115 		return -EOPNOTSUPP;
116 	}
117 
118 	rst_req = (comm_flags & (u32)(1 << COM_CHAN_RST_REQ_OFFSET)) >>
119 		COM_CHAN_RST_REQ_OFFSET;
120 	rst_ack = (comm_flags & (u32)(1 << COM_CHAN_RST_ACK_OFFSET)) >>
121 		COM_CHAN_RST_ACK_OFFSET;
122 	if (rst_req != rst_ack) {
123 		mlx4_err(dev, "Communication channel isn't sync, fail to send reset\n");
124 		return -EIO;
125 	}
126 
127 	rst_req ^= 1;
128 	mlx4_warn(dev, "VF is sending reset request to Firmware\n");
129 	comm_flags = rst_req << COM_CHAN_RST_REQ_OFFSET;
130 	__raw_writel((__force u32)cpu_to_be32(comm_flags),
131 		     (__iomem char *)priv->mfunc.comm + MLX4_COMM_CHAN_FLAGS);
132 	/* Make sure that our comm channel write doesn't
133 	 * get mixed in with writes from another CPU.
134 	 */
135 	mmiowb();
136 
137 	end = msecs_to_jiffies(MLX4_COMM_TIME) + jiffies;
138 	while (time_before(jiffies, end)) {
139 		comm_flags = swab32(readl((__iomem char *)priv->mfunc.comm +
140 					  MLX4_COMM_CHAN_FLAGS));
141 		rst_ack = (comm_flags & (u32)(1 << COM_CHAN_RST_ACK_OFFSET)) >>
142 			COM_CHAN_RST_ACK_OFFSET;
143 
144 		/* Reading rst_req again since the communication channel can
145 		 * be reset at any time by the PF and all its bits will be
146 		 * set to zero.
147 		 */
148 		rst_req = (comm_flags & (u32)(1 << COM_CHAN_RST_REQ_OFFSET)) >>
149 			COM_CHAN_RST_REQ_OFFSET;
150 
151 		if (rst_ack == rst_req) {
152 			mlx4_warn(dev, "VF Reset succeed\n");
153 			return 0;
154 		}
155 		cond_resched();
156 	}
157 	mlx4_err(dev, "Fail to send reset over the communication channel\n");
158 	return -ETIMEDOUT;
159 }
160 
161 int mlx4_comm_internal_err(u32 slave_read)
162 {
163 	return (u32)COMM_CHAN_EVENT_INTERNAL_ERR ==
164 		(slave_read & (u32)COMM_CHAN_EVENT_INTERNAL_ERR) ? 1 : 0;
165 }
166 
167 void mlx4_enter_error_state(struct mlx4_dev_persistent *persist)
168 {
169 	int err;
170 	struct mlx4_dev *dev;
171 
172 	if (!mlx4_internal_err_reset)
173 		return;
174 
175 	mutex_lock(&persist->device_state_mutex);
176 	if (persist->state & MLX4_DEVICE_STATE_INTERNAL_ERROR)
177 		goto out;
178 
179 	dev = persist->dev;
180 	mlx4_err(dev, "device is going to be reset\n");
181 	if (mlx4_is_slave(dev)) {
182 		err = mlx4_reset_slave(dev);
183 	} else {
184 		mlx4_crdump_collect(dev);
185 		err = mlx4_reset_master(dev);
186 	}
187 
188 	if (!err) {
189 		mlx4_err(dev, "device was reset successfully\n");
190 	} else {
191 		/* EEH could have disabled the PCI channel during reset. That's
192 		 * recoverable and the PCI error flow will handle it.
193 		 */
194 		if (!pci_channel_offline(dev->persist->pdev))
195 			BUG_ON(1);
196 	}
197 	dev->persist->state |= MLX4_DEVICE_STATE_INTERNAL_ERROR;
198 	mutex_unlock(&persist->device_state_mutex);
199 
200 	/* At that step HW was already reset, now notify clients */
201 	mlx4_dispatch_event(dev, MLX4_DEV_EVENT_CATASTROPHIC_ERROR, 0);
202 	mlx4_cmd_wake_completions(dev);
203 	return;
204 
205 out:
206 	mutex_unlock(&persist->device_state_mutex);
207 }
208 
209 static void mlx4_handle_error_state(struct mlx4_dev_persistent *persist)
210 {
211 	int err = 0;
212 
213 	mlx4_enter_error_state(persist);
214 	mutex_lock(&persist->interface_state_mutex);
215 	if (persist->interface_state & MLX4_INTERFACE_STATE_UP &&
216 	    !(persist->interface_state & MLX4_INTERFACE_STATE_DELETION)) {
217 		err = mlx4_restart_one(persist->pdev, false, NULL);
218 		mlx4_info(persist->dev, "mlx4_restart_one was ended, ret=%d\n",
219 			  err);
220 	}
221 	mutex_unlock(&persist->interface_state_mutex);
222 }
223 
224 static void dump_err_buf(struct mlx4_dev *dev)
225 {
226 	struct mlx4_priv *priv = mlx4_priv(dev);
227 
228 	int i;
229 
230 	mlx4_err(dev, "Internal error detected:\n");
231 	for (i = 0; i < priv->fw.catas_size; ++i)
232 		mlx4_err(dev, "  buf[%02x]: %08x\n",
233 			 i, swab32(readl(priv->catas_err.map + i)));
234 }
235 
236 static void poll_catas(struct timer_list *t)
237 {
238 	struct mlx4_priv *priv = from_timer(priv, t, catas_err.timer);
239 	struct mlx4_dev *dev = &priv->dev;
240 	u32 slave_read;
241 
242 	if (mlx4_is_slave(dev)) {
243 		slave_read = swab32(readl(&priv->mfunc.comm->slave_read));
244 		if (mlx4_comm_internal_err(slave_read)) {
245 			mlx4_warn(dev, "Internal error detected on the communication channel\n");
246 			goto internal_err;
247 		}
248 	} else if (readl(priv->catas_err.map)) {
249 		dump_err_buf(dev);
250 		goto internal_err;
251 	}
252 
253 	if (dev->persist->state & MLX4_DEVICE_STATE_INTERNAL_ERROR) {
254 		mlx4_warn(dev, "Internal error mark was detected on device\n");
255 		goto internal_err;
256 	}
257 
258 	mod_timer(&priv->catas_err.timer,
259 		  round_jiffies(jiffies + MLX4_CATAS_POLL_INTERVAL));
260 	return;
261 
262 internal_err:
263 	if (mlx4_internal_err_reset)
264 		queue_work(dev->persist->catas_wq, &dev->persist->catas_work);
265 }
266 
267 static void catas_reset(struct work_struct *work)
268 {
269 	struct mlx4_dev_persistent *persist =
270 		container_of(work, struct mlx4_dev_persistent,
271 			     catas_work);
272 
273 	mlx4_handle_error_state(persist);
274 }
275 
276 void mlx4_start_catas_poll(struct mlx4_dev *dev)
277 {
278 	struct mlx4_priv *priv = mlx4_priv(dev);
279 	phys_addr_t addr;
280 
281 	INIT_LIST_HEAD(&priv->catas_err.list);
282 	timer_setup(&priv->catas_err.timer, poll_catas, 0);
283 	priv->catas_err.map = NULL;
284 
285 	if (!mlx4_is_slave(dev)) {
286 		addr = pci_resource_start(dev->persist->pdev,
287 					  priv->fw.catas_bar) +
288 					  priv->fw.catas_offset;
289 
290 		priv->catas_err.map = ioremap(addr, priv->fw.catas_size * 4);
291 		if (!priv->catas_err.map) {
292 			mlx4_warn(dev, "Failed to map internal error buffer at 0x%llx\n",
293 				  (unsigned long long)addr);
294 			return;
295 		}
296 	}
297 
298 	priv->catas_err.timer.expires  =
299 		round_jiffies(jiffies + MLX4_CATAS_POLL_INTERVAL);
300 	add_timer(&priv->catas_err.timer);
301 }
302 
303 void mlx4_stop_catas_poll(struct mlx4_dev *dev)
304 {
305 	struct mlx4_priv *priv = mlx4_priv(dev);
306 
307 	del_timer_sync(&priv->catas_err.timer);
308 
309 	if (priv->catas_err.map) {
310 		iounmap(priv->catas_err.map);
311 		priv->catas_err.map = NULL;
312 	}
313 
314 	if (dev->persist->interface_state & MLX4_INTERFACE_STATE_DELETION)
315 		flush_workqueue(dev->persist->catas_wq);
316 }
317 
318 int  mlx4_catas_init(struct mlx4_dev *dev)
319 {
320 	INIT_WORK(&dev->persist->catas_work, catas_reset);
321 	dev->persist->catas_wq = create_singlethread_workqueue("mlx4_health");
322 	if (!dev->persist->catas_wq)
323 		return -ENOMEM;
324 
325 	return 0;
326 }
327 
328 void mlx4_catas_end(struct mlx4_dev *dev)
329 {
330 	if (dev->persist->catas_wq) {
331 		destroy_workqueue(dev->persist->catas_wq);
332 		dev->persist->catas_wq = NULL;
333 	}
334 }
335