Edit File: doorbell.h
/* * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #ifndef MLX5_DOORBELL_H #define MLX5_DOORBELL_H #define MLX5_BF_OFFSET 0x800 #define MLX5_CQ_DOORBELL 0x20 #if BITS_PER_LONG == 64 /* Assume that we can just write a 64-bit doorbell atomically. s390 * actually doesn't have writeq() but S/390 systems don't even have * PCI so we won't worry about it. */ #define MLX5_DECLARE_DOORBELL_LOCK(name) #define MLX5_INIT_DOORBELL_LOCK(ptr) do { } while (0) #define MLX5_GET_DOORBELL_LOCK(ptr) (NULL) static inline void mlx5_write64(__be32 val[2], void __iomem *dest, spinlock_t *doorbell_lock) { __raw_writeq(*(u64 *)val, dest); } #else /* Just fall back to a spinlock to protect the doorbell if * BITS_PER_LONG is 32 -- there's no portable way to do atomic 64-bit * MMIO writes. */ #define MLX5_DECLARE_DOORBELL_LOCK(name) spinlock_t name; #define MLX5_INIT_DOORBELL_LOCK(ptr) spin_lock_init(ptr) #define MLX5_GET_DOORBELL_LOCK(ptr) (ptr) static inline void mlx5_write64(__be32 val[2], void __iomem *dest, spinlock_t *doorbell_lock) { unsigned long flags; if (doorbell_lock) spin_lock_irqsave(doorbell_lock, flags); __raw_writel((__force u32) val[0], dest); __raw_writel((__force u32) val[1], dest + 4); if (doorbell_lock) spin_unlock_irqrestore(doorbell_lock, flags); } #endif #endif /* MLX5_DOORBELL_H */