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 
133 	end = msecs_to_jiffies(MLX4_COMM_TIME) + jiffies;
134 	while (time_before(jiffies, end)) {
135 		comm_flags = swab32(readl((__iomem char *)priv->mfunc.comm +
136 					  MLX4_COMM_CHAN_FLAGS));
137 		rst_ack = (comm_flags & (u32)(1 << COM_CHAN_RST_ACK_OFFSET)) >>
138 			COM_CHAN_RST_ACK_OFFSET;
139 
140 		/* Reading rst_req again since the communication channel can
141 		 * be reset at any time by the PF and all its bits will be
142 		 * set to zero.
143 		 */
144 		rst_req = (comm_flags & (u32)(1 << COM_CHAN_RST_REQ_OFFSET)) >>
145 			COM_CHAN_RST_REQ_OFFSET;
146 
147 		if (rst_ack == rst_req) {
148 			mlx4_warn(dev, "VF Reset succeed\n");
149 			return 0;
150 		}
151 		cond_resched();
152 	}
153 	mlx4_err(dev, "Fail to send reset over the communication channel\n");
154 	return -ETIMEDOUT;
155 }
156 
157 int mlx4_comm_internal_err(u32 slave_read)
158 {
159 	return (u32)COMM_CHAN_EVENT_INTERNAL_ERR ==
160 		(slave_read & (u32)COMM_CHAN_EVENT_INTERNAL_ERR) ? 1 : 0;
161 }
162 
163 void mlx4_enter_error_state(struct mlx4_dev_persistent *persist)
164 {
165 	int err;
166 	struct mlx4_dev *dev;
167 
168 	if (!mlx4_internal_err_reset)
169 		return;
170 
171 	mutex_lock(&persist->device_state_mutex);
172 	if (persist->state & MLX4_DEVICE_STATE_INTERNAL_ERROR)
173 		goto out;
174 
175 	dev = persist->dev;
176 	mlx4_err(dev, "device is going to be reset\n");
177 	if (mlx4_is_slave(dev)) {
178 		err = mlx4_reset_slave(dev);
179 	} else {
180 		mlx4_crdump_collect(dev);
181 		err = mlx4_reset_master(dev);
182 	}
183 
184 	if (!err) {
185 		mlx4_err(dev, "device was reset successfully\n");
186 	} else {
187 		/* EEH could have disabled the PCI channel during reset. That's
188 		 * recoverable and the PCI error flow will handle it.
189 		 */
190 		if (!pci_channel_offline(dev->persist->pdev))
191 			BUG_ON(1);
192 	}
193 	dev->persist->state |= MLX4_DEVICE_STATE_INTERNAL_ERROR;
194 	mutex_unlock(&persist->device_state_mutex);
195 
196 	/* At that step HW was already reset, now notify clients */
197 	mlx4_dispatch_event(dev, MLX4_DEV_EVENT_CATASTROPHIC_ERROR, 0);
198 	mlx4_cmd_wake_completions(dev);
199 	return;
200 
201 out:
202 	mutex_unlock(&persist->device_state_mutex);
203 }
204 
205 static void mlx4_handle_error_state(struct mlx4_dev_persistent *persist)
206 {
207 	struct mlx4_dev *dev = persist->dev;
208 	struct devlink *devlink;
209 	int err = 0;
210 
211 	mlx4_enter_error_state(persist);
212 	devlink = priv_to_devlink(mlx4_priv(dev));
213 	devl_lock(devlink);
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);
218 		mlx4_info(persist->dev, "mlx4_restart_one was ended, ret=%d\n",
219 			  err);
220 	}
221 	mutex_unlock(&persist->interface_state_mutex);
222 	devl_unlock(devlink);
223 }
224 
225 static void dump_err_buf(struct mlx4_dev *dev)
226 {
227 	struct mlx4_priv *priv = mlx4_priv(dev);
228 
229 	int i;
230 
231 	mlx4_err(dev, "Internal error detected:\n");
232 	for (i = 0; i < priv->fw.catas_size; ++i)
233 		mlx4_err(dev, "  buf[%02x]: %08x\n",
234 			 i, swab32(readl(priv->catas_err.map + i)));
235 }
236 
237 static void poll_catas(struct timer_list *t)
238 {
239 	struct mlx4_priv *priv = from_timer(priv, t, catas_err.timer);
240 	struct mlx4_dev *dev = &priv->dev;
241 	u32 slave_read;
242 
243 	if (mlx4_is_slave(dev)) {
244 		slave_read = swab32(readl(&priv->mfunc.comm->slave_read));
245 		if (mlx4_comm_internal_err(slave_read)) {
246 			mlx4_warn(dev, "Internal error detected on the communication channel\n");
247 			goto internal_err;
248 		}
249 	} else if (readl(priv->catas_err.map)) {
250 		dump_err_buf(dev);
251 		goto internal_err;
252 	}
253 
254 	if (dev->persist->state & MLX4_DEVICE_STATE_INTERNAL_ERROR) {
255 		mlx4_warn(dev, "Internal error mark was detected on device\n");
256 		goto internal_err;
257 	}
258 
259 	mod_timer(&priv->catas_err.timer,
260 		  round_jiffies(jiffies + MLX4_CATAS_POLL_INTERVAL));
261 	return;
262 
263 internal_err:
264 	if (mlx4_internal_err_reset)
265 		queue_work(dev->persist->catas_wq, &dev->persist->catas_work);
266 }
267 
268 static void catas_reset(struct work_struct *work)
269 {
270 	struct mlx4_dev_persistent *persist =
271 		container_of(work, struct mlx4_dev_persistent,
272 			     catas_work);
273 
274 	mlx4_handle_error_state(persist);
275 }
276 
277 void mlx4_start_catas_poll(struct mlx4_dev *dev)
278 {
279 	struct mlx4_priv *priv = mlx4_priv(dev);
280 	phys_addr_t addr;
281 
282 	INIT_LIST_HEAD(&priv->catas_err.list);
283 	timer_setup(&priv->catas_err.timer, poll_catas, 0);
284 	priv->catas_err.map = NULL;
285 
286 	if (!mlx4_is_slave(dev)) {
287 		addr = pci_resource_start(dev->persist->pdev,
288 					  priv->fw.catas_bar) +
289 					  priv->fw.catas_offset;
290 
291 		priv->catas_err.map = ioremap(addr, priv->fw.catas_size * 4);
292 		if (!priv->catas_err.map) {
293 			mlx4_warn(dev, "Failed to map internal error buffer at 0x%llx\n",
294 				  (unsigned long long)addr);
295 			return;
296 		}
297 	}
298 
299 	priv->catas_err.timer.expires  =
300 		round_jiffies(jiffies + MLX4_CATAS_POLL_INTERVAL);
301 	add_timer(&priv->catas_err.timer);
302 }
303 
304 void mlx4_stop_catas_poll(struct mlx4_dev *dev)
305 {
306 	struct mlx4_priv *priv = mlx4_priv(dev);
307 
308 	del_timer_sync(&priv->catas_err.timer);
309 
310 	if (priv->catas_err.map) {
311 		iounmap(priv->catas_err.map);
312 		priv->catas_err.map = NULL;
313 	}
314 
315 	if (dev->persist->interface_state & MLX4_INTERFACE_STATE_DELETION)
316 		flush_workqueue(dev->persist->catas_wq);
317 }
318 
319 int  mlx4_catas_init(struct mlx4_dev *dev)
320 {
321 	INIT_WORK(&dev->persist->catas_work, catas_reset);
322 	dev->persist->catas_wq = create_singlethread_workqueue("mlx4_health");
323 	if (!dev->persist->catas_wq)
324 		return -ENOMEM;
325 
326 	return 0;
327 }
328 
329 void mlx4_catas_end(struct mlx4_dev *dev)
330 {
331 	if (dev->persist->catas_wq) {
332 		destroy_workqueue(dev->persist->catas_wq);
333 		dev->persist->catas_wq = NULL;
334 	}
335 }
336