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 #include <linux/types.h>
36
37 #define MTHCA_RD_DOORBELL 0x00
38 #define MTHCA_SEND_DOORBELL 0x10
39 #define MTHCA_RECEIVE_DOORBELL 0x18
40 #define MTHCA_CQ_DOORBELL 0x20
41 #define MTHCA_EQ_DOORBELL 0x28
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 MTHCA_DECLARE_DOORBELL_LOCK(name)
51 #define MTHCA_INIT_DOORBELL_LOCK(ptr) do { } while (0)
52 #define MTHCA_GET_DOORBELL_LOCK(ptr) (NULL)
53
54 static inline void mthca_write64_raw(__be64 val, void __iomem *dest)
55 {
56 __raw_writeq((__force u64) val, dest);
57 }
58
59 static inline void mthca_write64(u32 hi, u32 lo, void __iomem *dest,
60 spinlock_t *doorbell_lock)
61 {
62 __raw_writeq((__force u64) cpu_to_be64((u64) hi << 32 | lo), dest);
63 }
64
65 static inline void mthca_write_db_rec(__be32 val[2], __be32 *db)
66 {
67 *(u64 *) db = *(u64 *) val;
68 }
69
70 #else
71
72 /*
73 * Just fall back to a spinlock to protect the doorbell if
74 * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit
75 * MMIO writes.
76 */
77
78 #define MTHCA_DECLARE_DOORBELL_LOCK(name) spinlock_t name;
79 #define MTHCA_INIT_DOORBELL_LOCK(ptr) spin_lock_init(ptr)
80 #define MTHCA_GET_DOORBELL_LOCK(ptr) (ptr)
81
82 static inline void mthca_write64_raw(__be64 val, void __iomem *dest)
83 {
84 __raw_writel(((__force u32 *) &val)[0], dest);
85 __raw_writel(((__force u32 *) &val)[1], dest + 4);
86 }
87
88 static inline void mthca_write64(u32 hi, u32 lo, void __iomem *dest,
89 spinlock_t *doorbell_lock)
90 {
91 unsigned long flags;
92
93 hi = (__force u32) cpu_to_be32(hi);
94 lo = (__force u32) cpu_to_be32(lo);
95
96 spin_lock_irqsave(doorbell_lock, flags);
97 __raw_writel(hi, dest);
98 __raw_writel(lo, dest + 4);
99 spin_unlock_irqrestore(doorbell_lock, flags);
100 }
101
102 static inline void mthca_write_db_rec(__be32 val[2], __be32 *db)
103 {
104 db[0] = val[0];
105 wmb();
106 db[1] = val[1];
107 }
108
109 #endif