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 #ifdef __linux__
47 u32 *bridge_header = NULL;
48 #endif
49 struct pci_dev *bridge = NULL;
50 #ifdef __linux__
51 int bridge_pcix_cap = 0;
52 #endif
53 int hca_pcie_cap = 0;
54 int hca_pcix_cap = 0;
55
56 u16 devctl;
57 u16 linkctl;
58
59 #define MTHCA_RESET_OFFSET 0xf0010
60 #define MTHCA_RESET_VALUE swab32(1)
61
62 /*
63 * Reset the chip. This is somewhat ugly because we have to
64 * save off the PCI header before reset and then restore it
65 * after the chip reboots. We skip config space offsets 22
66 * and 23 since those have a special meaning.
67 *
68 * To make matters worse, for Tavor (PCI-X HCA) we have to
69 * find the associated bridge device and save off its PCI
70 * header as well.
71 */
72
73 if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
74 /* Look for the bridge -- its device ID will be 2 more
75 than HCA's device ID. */
76 #ifdef __linux__
77 while ((bridge = pci_get_device(mdev->pdev->vendor,
78 mdev->pdev->device + 2,
79 bridge)) != NULL) {
80 if (bridge->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
81 bridge->subordinate == mdev->pdev->bus) {
82 mthca_dbg(mdev, "Found bridge: %s\n",
83 pci_name(bridge));
84 break;
85 }
86 }
87
88 if (!bridge) {
89 /*
90 * Didn't find a bridge for a Tavor device --
91 * assume we're in no-bridge mode and hope for
92 * the best.
93 */
94 mthca_warn(mdev, "No bridge found for %s\n",
95 pci_name(mdev->pdev));
96 }
97 #else
98 mthca_warn(mdev, "Reset on PCI-X is not supported.\n");
99 goto out;
100
101 #endif
102 }
103
104 /* For Arbel do we need to save off the full 4K PCI Express header?? */
105 hca_header = kmalloc(256, GFP_KERNEL);
106 if (!hca_header) {
107 err = -ENOMEM;
108 mthca_err(mdev, "Couldn't allocate memory to save HCA "
109 "PCI header, aborting.\n");
110 goto out;
111 }
112
113 for (i = 0; i < 64; ++i) {
114 if (i == 22 || i == 23)
115 continue;
116 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
117 err = -ENODEV;
118 mthca_err(mdev, "Couldn't save HCA "
119 "PCI header, aborting.\n");
120 goto out;
121 }
122 }
123
124 hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
125 hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
126
127 #ifdef __linux__
128 if (bridge) {
129 bridge_header = kmalloc(256, GFP_KERNEL);
130 if (!bridge_header) {
131 err = -ENOMEM;
132 mthca_err(mdev, "Couldn't allocate memory to save HCA "
133 "bridge PCI header, aborting.\n");
134 goto out;
135 }
136
137 for (i = 0; i < 64; ++i) {
138 if (i == 22 || i == 23)
139 continue;
140 if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
141 err = -ENODEV;
142 mthca_err(mdev, "Couldn't save HCA bridge "
143 "PCI header, aborting.\n");
144 goto out;
145 }
146 }
147 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
148 if (!bridge_pcix_cap) {
149 err = -ENODEV;
150 mthca_err(mdev, "Couldn't locate HCA bridge "
151 "PCI-X capability, aborting.\n");
152 goto out;
153 }
154 }
155 #endif
156
157 /* actually hit reset */
158 {
159 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
160 MTHCA_RESET_OFFSET, 4);
161
162 if (!reset) {
163 err = -ENOMEM;
164 mthca_err(mdev, "Couldn't map HCA reset register, "
165 "aborting.\n");
166 goto out;
167 }
168
169 writel(MTHCA_RESET_VALUE, reset);
170 iounmap(reset);
171 }
172
173 /* Docs say to wait one second before accessing device */
174 msleep(1000);
175
176 /* Now wait for PCI device to start responding again */
177 {
178 u32 v;
179 int c = 0;
180
181 for (c = 0; c < 100; ++c) {
182 if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
183 err = -ENODEV;
184 mthca_err(mdev, "Couldn't access HCA after reset, "
185 "aborting.\n");
186 goto out;
187 }
188
189 if (v != 0xffffffff)
190 goto good;
191
192 msleep(100);
193 }
194
195 err = -ENODEV;
196 mthca_err(mdev, "PCI device did not come back after reset, "
197 "aborting.\n");
198 goto out;
199 }
200
201 good:
202 #ifdef __linux__
203 /* Now restore the PCI headers */
204 if (bridge) {
205 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
206 bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
207 err = -ENODEV;
208 mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
209 "split transaction control, aborting.\n");
210 goto out;
211 }
212 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
213 bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
214 err = -ENODEV;
215 mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
216 "split transaction control, aborting.\n");
217 goto out;
218 }
219 /*
220 * Bridge control register is at 0x3e, so we'll
221 * naturally restore it last in this loop.
222 */
223 for (i = 0; i < 16; ++i) {
224 if (i * 4 == PCI_COMMAND)
225 continue;
226
227 if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
228 err = -ENODEV;
229 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
230 "aborting.\n", i);
231 goto out;
232 }
233 }
234
235 if (pci_write_config_dword(bridge, PCI_COMMAND,
236 bridge_header[PCI_COMMAND / 4])) {
237 err = -ENODEV;
238 mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
239 "aborting.\n");
240 goto out;
241 }
242 }
243 #endif
244
245 if (hca_pcix_cap) {
246 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
247 hca_header[hca_pcix_cap / 4])) {
248 err = -ENODEV;
249 mthca_err(mdev, "Couldn't restore HCA PCI-X "
250 "command register, aborting.\n");
251 goto out;
252 }
253 }
254
255 if (hca_pcie_cap) {
256 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
257 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
258 devctl)) {
259 err = -ENODEV;
260 mthca_err(mdev, "Couldn't restore HCA PCI Express "
261 "Device Control register, aborting.\n");
262 goto out;
263 }
264 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
265 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
266 linkctl)) {
267 err = -ENODEV;
268 mthca_err(mdev, "Couldn't restore HCA PCI Express "
269 "Link control register, aborting.\n");
270 goto out;
271 }
272 }
273
274 for (i = 0; i < 16; ++i) {
275 if (i * 4 == PCI_COMMAND)
276 continue;
277
278 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
279 err = -ENODEV;
280 mthca_err(mdev, "Couldn't restore HCA reg %x, "
281 "aborting.\n", i);
282 goto out;
283 }
284 }
285
286 if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
287 hca_header[PCI_COMMAND / 4])) {
288 err = -ENODEV;
289 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
290 "aborting.\n");
291 goto out;
292 }
293
294 out:
295 #ifdef __linux__
296 if (bridge)
297 pci_dev_put(bridge);
298 kfree(bridge_header);
299 #endif
300 kfree(hca_header);
301
302 return err;
303 }
304