Merge rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / drivers / infiniband / hw / mthca / mthca_reset.c
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  * $Id: mthca_reset.c 1349 2004-12-16 21:09:43Z roland $
33  */
34
35 #include <linux/config.h>
36 #include <linux/init.h>
37 #include <linux/errno.h>
38 #include <linux/pci.h>
39 #include <linux/delay.h>
40 #include <linux/slab.h>
41
42 #include "mthca_dev.h"
43 #include "mthca_cmd.h"
44
45 int mthca_reset(struct mthca_dev *mdev)
46 {
47         int i;
48         int err = 0;
49         u32 *hca_header    = NULL;
50         u32 *bridge_header = NULL;
51         struct pci_dev *bridge = NULL;
52         int bridge_pcix_cap = 0;
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                 while ((bridge = pci_get_device(mdev->pdev->vendor,
77                                                 mdev->pdev->device + 2,
78                                                 bridge)) != NULL) {
79                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
80                             bridge->subordinate == mdev->pdev->bus) {
81                                 mthca_dbg(mdev, "Found bridge: %s\n",
82                                           pci_name(bridge));
83                                 break;
84                         }
85                 }
86
87                 if (!bridge) {
88                         /*
89                          * Didn't find a bridge for a Tavor device --
90                          * assume we're in no-bridge mode and hope for
91                          * the best.
92                          */
93                         mthca_warn(mdev, "No bridge found for %s\n",
94                                   pci_name(mdev->pdev));
95                 }
96
97         }
98
99         /* For Arbel do we need to save off the full 4K PCI Express header?? */
100         hca_header = kmalloc(256, GFP_KERNEL);
101         if (!hca_header) {
102                 err = -ENOMEM;
103                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
104                           "PCI header, aborting.\n");
105                 goto out;
106         }
107
108         for (i = 0; i < 64; ++i) {
109                 if (i == 22 || i == 23)
110                         continue;
111                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
112                         err = -ENODEV;
113                         mthca_err(mdev, "Couldn't save HCA "
114                                   "PCI header, aborting.\n");
115                         goto out;
116                 }
117         }
118
119         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
120         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
121
122         if (bridge) {
123                 bridge_header = kmalloc(256, GFP_KERNEL);
124                 if (!bridge_header) {
125                         err = -ENOMEM;
126                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
127                                   "bridge PCI header, aborting.\n");
128                         goto out;
129                 }
130
131                 for (i = 0; i < 64; ++i) {
132                         if (i == 22 || i == 23)
133                                 continue;
134                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
135                                 err = -ENODEV;
136                                 mthca_err(mdev, "Couldn't save HCA bridge "
137                                           "PCI header, aborting.\n");
138                                 goto out;
139                         }
140                 }
141                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
142                 if (!bridge_pcix_cap) {
143                                 err = -ENODEV;
144                                 mthca_err(mdev, "Couldn't locate HCA bridge "
145                                           "PCI-X capability, aborting.\n");
146                                 goto out;
147                 }
148         }
149
150         /* actually hit reset */
151         {
152                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
153                                               MTHCA_RESET_OFFSET, 4);
154
155                 if (!reset) {
156                         err = -ENOMEM;
157                         mthca_err(mdev, "Couldn't map HCA reset register, "
158                                   "aborting.\n");
159                         goto out;
160                 }
161
162                 writel(MTHCA_RESET_VALUE, reset);
163                 iounmap(reset);
164         }
165
166         /* Docs say to wait one second before accessing device */
167         msleep(1000);
168
169         /* Now wait for PCI device to start responding again */
170         {
171                 u32 v;
172                 int c = 0;
173
174                 for (c = 0; c < 100; ++c) {
175                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
176                                 err = -ENODEV;
177                                 mthca_err(mdev, "Couldn't access HCA after reset, "
178                                           "aborting.\n");
179                                 goto out;
180                         }
181
182                         if (v != 0xffffffff)
183                                 goto good;
184
185                         msleep(100);
186                 }
187
188                 err = -ENODEV;
189                 mthca_err(mdev, "PCI device did not come back after reset, "
190                           "aborting.\n");
191                 goto out;
192         }
193
194 good:
195         /* Now restore the PCI headers */
196         if (bridge) {
197                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
198                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
199                         err = -ENODEV;
200                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
201                                   "split transaction control, aborting.\n");
202                         goto out;
203                 }
204                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
205                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
206                         err = -ENODEV;
207                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
208                                   "split transaction control, aborting.\n");
209                         goto out;
210                 }
211                 /*
212                  * Bridge control register is at 0x3e, so we'll
213                  * naturally restore it last in this loop.
214                  */
215                 for (i = 0; i < 16; ++i) {
216                         if (i * 4 == PCI_COMMAND)
217                                 continue;
218
219                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
220                                 err = -ENODEV;
221                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
222                                           "aborting.\n", i);
223                                 goto out;
224                         }
225                 }
226
227                 if (pci_write_config_dword(bridge, PCI_COMMAND,
228                                            bridge_header[PCI_COMMAND / 4])) {
229                         err = -ENODEV;
230                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
231                                   "aborting.\n");
232                         goto out;
233                 }
234         }
235
236         if (hca_pcix_cap) {
237                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
238                                  hca_header[hca_pcix_cap / 4])) {
239                         err = -ENODEV;
240                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
241                                   "command register, aborting.\n");
242                         goto out;
243                 }
244         }
245
246         if (hca_pcie_cap) {
247                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
248                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
249                                            devctl)) {
250                         err = -ENODEV;
251                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
252                                   "Device Control register, aborting.\n");
253                         goto out;
254                 }
255                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
256                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
257                                            linkctl)) {
258                         err = -ENODEV;
259                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
260                                   "Link control register, aborting.\n");
261                         goto out;
262                 }
263         }
264
265         for (i = 0; i < 16; ++i) {
266                 if (i * 4 == PCI_COMMAND)
267                         continue;
268
269                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
270                         err = -ENODEV;
271                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
272                                   "aborting.\n", i);
273                         goto out;
274                 }
275         }
276
277         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
278                                    hca_header[PCI_COMMAND / 4])) {
279                 err = -ENODEV;
280                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
281                           "aborting.\n");
282                 goto out;
283         }
284
285 out:
286         if (bridge)
287                 pci_dev_put(bridge);
288         kfree(bridge_header);
289         kfree(hca_header);
290
291         return err;
292 }