1/*
2 * Copyright (c) 2004 Topspin Communications.  All rights reserved.
3 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
4 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses.  You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * OpenIB.org BSD license below:
11 *
12 *     Redistribution and use in source and binary forms, with or
13 *     without modification, are permitted provided that the following
14 *     conditions are met:
15 *
16 *      - Redistributions of source code must retain the above
17 *        copyright notice, this list of conditions and the following
18 *        disclaimer.
19 *
20 *      - Redistributions in binary form must reproduce the above
21 *        copyright notice, this list of conditions and the following
22 *        disclaimer in the documentation and/or other materials
23 *        provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 */
34
35#ifndef MLX4_DOORBELL_H
36#define MLX4_DOORBELL_H
37
38#include <linux/io.h>
39
40#define MLX4_SEND_DOORBELL    0x14
41#define MLX4_CQ_DOORBELL      0x20
42
43#if BITS_PER_LONG == 64
44/*
45 * Assume that we can just write a 64-bit doorbell atomically.  s390
46 * actually doesn't have writeq() but S/390 systems don't even have
47 * PCI so we won't worry about it.
48 */
49
50#define MLX4_DECLARE_DOORBELL_LOCK(name)
51#define MLX4_INIT_DOORBELL_LOCK(ptr)    do { } while (0)
52#define MLX4_GET_DOORBELL_LOCK(ptr)      (NULL)
53
54static inline void mlx4_write64(__be32 val[2], void /*__iomem*/*dest/*,
55		 spinlock_t *doorbell_lock*/)
56{
57	__raw_writeq(*(u64 *) val, dest);
58}
59
60#else
61
62/*
63 * Just fall back to a spinlock to protect the doorbell if
64 * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit
65 * MMIO writes.
66 */
67
68#define MLX4_DECLARE_DOORBELL_LOCK(name) spinlock_t name;
69#define MLX4_INIT_DOORBELL_LOCK(ptr)     spin_lock_init(ptr)
70#define MLX4_GET_DOORBELL_LOCK(ptr)      (ptr)
71
72static inline void mlx4_write64(__be32 val[2], void /*__iomem*/*dest) {
73	/*unsigned long flags;*/
74
75	/*spin_lock_irqsave(doorbell_lock, flags);*/
76	__raw_writel((/*__force*/u32) val[0], dest);
77	__raw_writel((/*__force*/u32) val[1], (u8 *) dest + 4);
78	/*spin_unlock_irqrestore(doorbell_lock, flags);*/
79}
80
81#endif
82
83#endif /* MLX4_DOORBELL_H */
84