LXR linux/drivers/infiniband/hw/mthca/mthca

   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
  54static inline void mthca_write64_raw(__be64 val, void __iomem *dest)
  55{
  56        __raw_writeq((__force u64) val, dest);
  57}
  58
  59static 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
  65static 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
  82static 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
  88static 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
 102static 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
 110