xref: /trueos/sys/ofed/drivers/infiniband/hw/mthca/mthca_reset.c (revision 7a1ab70b9590c4c122be3d913b579be45424f95a)
1 /*
2  * Copyright (c) 2004 Topspin Communications.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/errno.h>
34 #include <linux/pci.h>
35 #include <linux/delay.h>
36 #include <linux/slab.h>
37 
38 #include "mthca_dev.h"
39 #include "mthca_cmd.h"
40 
mthca_reset(struct mthca_dev * mdev)41 int mthca_reset(struct mthca_dev *mdev)
42 {
43 	int i;
44 	int err = 0;
45 	u32 *hca_header    = NULL;
46 	u32 *bridge_header = NULL;
47 	struct pci_dev *bridge = NULL;
48 	int bridge_pcix_cap = 0;
49 	int hca_pcie_cap = 0;
50 	int hca_pcix_cap = 0;
51 
52 	u16 devctl;
53 	u16 linkctl;
54 
55 #define MTHCA_RESET_OFFSET 0xf0010
56 #define MTHCA_RESET_VALUE  swab32(1)
57 
58 	/*
59 	 * Reset the chip.  This is somewhat ugly because we have to
60 	 * save off the PCI header before reset and then restore it
61 	 * after the chip reboots.  We skip config space offsets 22
62 	 * and 23 since those have a special meaning.
63 	 *
64 	 * To make matters worse, for Tavor (PCI-X HCA) we have to
65 	 * find the associated bridge device and save off its PCI
66 	 * header as well.
67 	 */
68 
69 	if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
70 		/* Look for the bridge -- its device ID will be 2 more
71 		   than HCA's device ID. */
72 #ifdef __linux__
73 		while ((bridge = pci_get_device(mdev->pdev->vendor,
74 						mdev->pdev->device + 2,
75 						bridge)) != NULL) {
76 			if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
77 			    bridge->subordinate == mdev->pdev->bus) {
78 				mthca_dbg(mdev, "Found bridge: %s\n",
79 					  pci_name(bridge));
80 				break;
81 			}
82 		}
83 
84 		if (!bridge) {
85 			/*
86 			 * Didn't find a bridge for a Tavor device --
87 			 * assume we're in no-bridge mode and hope for
88 			 * the best.
89 			 */
90 			mthca_warn(mdev, "No bridge found for %s\n",
91 				  pci_name(mdev->pdev));
92 		}
93 #else
94 		mthca_warn(mdev, "Reset on PCI-X is not supported.\n");
95 		goto out;
96 
97 #endif
98 	}
99 
100 	/* For Arbel do we need to save off the full 4K PCI Express header?? */
101 	hca_header = kmalloc(256, GFP_KERNEL);
102 	if (!hca_header) {
103 		err = -ENOMEM;
104 		mthca_err(mdev, "Couldn't allocate memory to save HCA "
105 			  "PCI header, aborting.\n");
106 		goto out;
107 	}
108 
109 	for (i = 0; i < 64; ++i) {
110 		if (i == 22 || i == 23)
111 			continue;
112 		if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
113 			err = -ENODEV;
114 			mthca_err(mdev, "Couldn't save HCA "
115 				  "PCI header, aborting.\n");
116 			goto out;
117 		}
118 	}
119 
120 	hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
121 	hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
122 
123 #ifdef __linux__
124 	if (bridge) {
125 		bridge_header = kmalloc(256, GFP_KERNEL);
126 		if (!bridge_header) {
127 			err = -ENOMEM;
128 			mthca_err(mdev, "Couldn't allocate memory to save HCA "
129 				  "bridge PCI header, aborting.\n");
130 			goto out;
131 		}
132 
133 		for (i = 0; i < 64; ++i) {
134 			if (i == 22 || i == 23)
135 				continue;
136 			if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
137 				err = -ENODEV;
138 				mthca_err(mdev, "Couldn't save HCA bridge "
139 					  "PCI header, aborting.\n");
140 				goto out;
141 			}
142 		}
143 		bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
144 		if (!bridge_pcix_cap) {
145 				err = -ENODEV;
146 				mthca_err(mdev, "Couldn't locate HCA bridge "
147 					  "PCI-X capability, aborting.\n");
148 				goto out;
149 		}
150 	}
151 #endif
152 
153 	/* actually hit reset */
154 	{
155 		void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
156 					      MTHCA_RESET_OFFSET, 4);
157 
158 		if (!reset) {
159 			err = -ENOMEM;
160 			mthca_err(mdev, "Couldn't map HCA reset register, "
161 				  "aborting.\n");
162 			goto out;
163 		}
164 
165 		writel(MTHCA_RESET_VALUE, reset);
166 		iounmap(reset);
167 	}
168 
169 	/* Docs say to wait one second before accessing device */
170 	msleep(1000);
171 
172 	/* Now wait for PCI device to start responding again */
173 	{
174 		u32 v;
175 		int c = 0;
176 
177 		for (c = 0; c < 100; ++c) {
178 			if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
179 				err = -ENODEV;
180 				mthca_err(mdev, "Couldn't access HCA after reset, "
181 					  "aborting.\n");
182 				goto out;
183 			}
184 
185 			if (v != 0xffffffff)
186 				goto good;
187 
188 			msleep(100);
189 		}
190 
191 		err = -ENODEV;
192 		mthca_err(mdev, "PCI device did not come back after reset, "
193 			  "aborting.\n");
194 		goto out;
195 	}
196 
197 good:
198 	/* Now restore the PCI headers */
199 	if (bridge) {
200 		if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
201 				 bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
202 			err = -ENODEV;
203 			mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
204 				  "split transaction control, aborting.\n");
205 			goto out;
206 		}
207 		if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
208 				 bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
209 			err = -ENODEV;
210 			mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
211 				  "split transaction control, aborting.\n");
212 			goto out;
213 		}
214 		/*
215 		 * Bridge control register is at 0x3e, so we'll
216 		 * naturally restore it last in this loop.
217 		 */
218 		for (i = 0; i < 16; ++i) {
219 			if (i * 4 == PCI_COMMAND)
220 				continue;
221 
222 			if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
223 				err = -ENODEV;
224 				mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
225 					  "aborting.\n", i);
226 				goto out;
227 			}
228 		}
229 
230 		if (pci_write_config_dword(bridge, PCI_COMMAND,
231 					   bridge_header[PCI_COMMAND / 4])) {
232 			err = -ENODEV;
233 			mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
234 				  "aborting.\n");
235 			goto out;
236 		}
237 	}
238 
239 	if (hca_pcix_cap) {
240 		if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
241 				 hca_header[hca_pcix_cap / 4])) {
242 			err = -ENODEV;
243 			mthca_err(mdev, "Couldn't restore HCA PCI-X "
244 				  "command register, aborting.\n");
245 			goto out;
246 		}
247 	}
248 
249 	if (hca_pcie_cap) {
250 		devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
251 		if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
252 					   devctl)) {
253 			err = -ENODEV;
254 			mthca_err(mdev, "Couldn't restore HCA PCI Express "
255 				  "Device Control register, aborting.\n");
256 			goto out;
257 		}
258 		linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
259 		if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
260 					   linkctl)) {
261 			err = -ENODEV;
262 			mthca_err(mdev, "Couldn't restore HCA PCI Express "
263 				  "Link control register, aborting.\n");
264 			goto out;
265 		}
266 	}
267 
268 	for (i = 0; i < 16; ++i) {
269 		if (i * 4 == PCI_COMMAND)
270 			continue;
271 
272 		if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
273 			err = -ENODEV;
274 			mthca_err(mdev, "Couldn't restore HCA reg %x, "
275 				  "aborting.\n", i);
276 			goto out;
277 		}
278 	}
279 
280 	if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
281 				   hca_header[PCI_COMMAND / 4])) {
282 		err = -ENODEV;
283 		mthca_err(mdev, "Couldn't restore HCA COMMAND, "
284 			  "aborting.\n");
285 		goto out;
286 	}
287 
288 out:
289 #ifdef __linux__
290 	if (bridge)
291 		pci_dev_put(bridge);
292 #endif
293 	kfree(bridge_header);
294 	kfree(hca_header);
295 
296 	return err;
297 }
298