2 * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
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33 #ifndef MLX5_DOORBELL_H
34 #define MLX5_DOORBELL_H
36 #define MLX5_BF_OFFSET 0x800
37 #define MLX5_CQ_DOORBELL 0x20
39 /* Assume that we can just write a 64-bit doorbell atomically. s390
40 * actually doesn't have writeq() but S/390 systems don't even have
41 * PCI so we won't worry about it.
43 * Note that the write is not atomic on 32-bit systems! In contrast to 64-bit
44 * ones, it requires proper locking. mlx5_write64 doesn't do any locking, so use
45 * it at your own discretion, protected by some kind of lock on 32 bits.
47 * TODO: use write{q,l}_relaxed()
50 static inline void mlx5_write64(__be32 val[2], void __iomem *dest)
52 #if BITS_PER_LONG == 64
53 __raw_writeq(*(u64 *)val, dest);
55 __raw_writel((__force u32) val[0], dest);
56 __raw_writel((__force u32) val[1], dest + 4);
60 #endif /* MLX5_DOORBELL_H */