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/types.h> |
39 | #include <linux/io.h> |
40 | |
41 | #define MLX4_SEND_DOORBELL 0x14 |
42 | #define MLX4_CQ_DOORBELL 0x20 |
43 | |
44 | #if BITS_PER_LONG == 64 |
45 | /* |
46 | * Assume that we can just write a 64-bit doorbell atomically. s390 |
47 | * actually doesn't have writeq() but S/390 systems don't even have |
48 | * PCI so we won't worry about it. |
49 | */ |
50 | |
51 | #define MLX4_DECLARE_DOORBELL_LOCK(name) |
52 | #define MLX4_INIT_DOORBELL_LOCK(ptr) do { } while (0) |
53 | #define MLX4_GET_DOORBELL_LOCK(ptr) (NULL) |
54 | |
55 | static inline void mlx4_write64(__be32 val[2], void __iomem *dest, |
56 | spinlock_t *doorbell_lock) |
57 | { |
58 | __raw_writeq(val: *(u64 *) val, addr: dest); |
59 | } |
60 | |
61 | #else |
62 | |
63 | /* |
64 | * Just fall back to a spinlock to protect the doorbell if |
65 | * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit |
66 | * MMIO writes. |
67 | */ |
68 | |
69 | #define MLX4_DECLARE_DOORBELL_LOCK(name) spinlock_t name; |
70 | #define MLX4_INIT_DOORBELL_LOCK(ptr) spin_lock_init(ptr) |
71 | #define MLX4_GET_DOORBELL_LOCK(ptr) (ptr) |
72 | |
73 | static inline void mlx4_write64(__be32 val[2], void __iomem *dest, |
74 | spinlock_t *doorbell_lock) |
75 | { |
76 | unsigned long flags; |
77 | |
78 | spin_lock_irqsave(doorbell_lock, flags); |
79 | __raw_writel((__force u32) val[0], dest); |
80 | __raw_writel((__force u32) val[1], dest + 4); |
81 | spin_unlock_irqrestore(doorbell_lock, flags); |
82 | } |
83 | |
84 | #endif |
85 | |
86 | #endif /* MLX4_DOORBELL_H */ |
87 | |