blob: 163a818411e71742c332417c0bdfb811669f663f [file] [log] [blame]
Eli Cohene126ba92013-07-07 17:25:49 +03001/*
2 * Copyright (c) 2013, Mellanox Technologies inc. 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#ifndef MLX5_DOORBELL_H
34#define MLX5_DOORBELL_H
35
36#define MLX5_BF_OFFSET 0x800
37#define MLX5_CQ_DOORBELL 0x20
38
39#if BITS_PER_LONG == 64
40/* Assume that we can just write a 64-bit doorbell atomically. s390
41 * actually doesn't have writeq() but S/390 systems don't even have
42 * PCI so we won't worry about it.
43 */
44
45#define MLX5_DECLARE_DOORBELL_LOCK(name)
46#define MLX5_INIT_DOORBELL_LOCK(ptr) do { } while (0)
47#define MLX5_GET_DOORBELL_LOCK(ptr) (NULL)
48
49static inline void mlx5_write64(__be32 val[2], void __iomem *dest,
50 spinlock_t *doorbell_lock)
51{
52 __raw_writeq(*(u64 *)val, dest);
53}
54
55#else
56
57/* Just fall back to a spinlock to protect the doorbell if
58 * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit
59 * MMIO writes.
60 */
61
62#define MLX5_DECLARE_DOORBELL_LOCK(name) spinlock_t name;
63#define MLX5_INIT_DOORBELL_LOCK(ptr) spin_lock_init(ptr)
64#define MLX5_GET_DOORBELL_LOCK(ptr) (ptr)
65
66static inline void mlx5_write64(__be32 val[2], void __iomem *dest,
67 spinlock_t *doorbell_lock)
68{
69 unsigned long flags;
70
71 spin_lock_irqsave(doorbell_lock, flags);
72 __raw_writel((__force u32) val[0], dest);
73 __raw_writel((__force u32) val[1], dest + 4);
74 spin_unlock_irqrestore(doorbell_lock, flags);
75}
76
77#endif
78
79#endif /* MLX5_DOORBELL_H */