1 /*
2  * Copyright 2015 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs <bskeggs@redhat.com>
23  */
24 #include "priv.h"
25 
26 #include <core/pci.h>
27 
28 void
29 g84_pci_init(struct nvkm_pci *pci)
30 {
31 	/* The following only concerns PCIe cards. */
32 	if (!pci_is_pcie(pci->pdev))
33 		return;
34 
35 	/* Tag field is 8-bit long, regardless of EXT_TAG.
36 	 * However, if EXT_TAG is disabled, only the lower 5 bits of the tag
37 	 * field should be used, limiting the number of request to 32.
38 	 *
39 	 * Apparently, 0x041c stores some limit on the number of requests
40 	 * possible, so if EXT_TAG is disabled, limit that requests number to
41 	 * 32
42 	 *
43 	 * Fixes fdo#86537
44 	 */
45 	if (nvkm_pci_rd32(pci, 0x007c) & 0x00000020)
46 		nvkm_pci_mask(pci, 0x0080, 0x00000100, 0x00000100);
47 	else
48 		nvkm_pci_mask(pci, 0x041c, 0x00000060, 0x00000000);
49 }
50 
51 static const struct nvkm_pci_func
52 g84_pci_func = {
53 	.init = g84_pci_init,
54 	.rd32 = nv40_pci_rd32,
55 	.wr08 = nv40_pci_wr08,
56 	.wr32 = nv40_pci_wr32,
57 	.msi_rearm = nv46_pci_msi_rearm,
58 };
59 
60 int
61 g84_pci_new(struct nvkm_device *device, int index, struct nvkm_pci **ppci)
62 {
63 	return nvkm_pci_new_(&g84_pci_func, device, index, ppci);
64 }
65