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(*(u64 *) val, 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], (u8 *)dest + 4); 81 spin_unlock_irqrestore(doorbell_lock, flags); 82 } 83 84 #endif 85 86 #endif /* MLX4_DOORBELL_H */ 87