drivers/rapidio/rio-access.c

   1 /*
   2  * RapidIO configuration space access support
   3  *
   4  * Copyright 2005 MontaVista Software, Inc.
   5  * Matt Porter <mporter@kernel.crashing.org>
   6  *
   7  * This program is free software; you can redistribute  it and/or modify it
   8  * under  the terms of  the GNU General  Public License as published by the
   9  * Free Software Foundation;  either version 2 of the  License, or (at your
  10  * option) any later version.
  11  */
  12
  13 #include <linux/rio.h>
  14 #include <linux/module.h>
  15
  16 /*
  17  * These interrupt-safe spinlocks protect all accesses to RIO
  18  * configuration space and doorbell access.
  19  */
  20 static spinlock_t rio_config_lock = SPIN_LOCK_UNLOCKED;
  21 static spinlock_t rio_doorbell_lock = SPIN_LOCK_UNLOCKED;
  22
  23 /*
  24  *  Wrappers for all RIO configuration access functions.  They just check
  25  *  alignment, do locking and call the low-level functions pointed to
  26  *  by rio_mport->ops.
  27  */
  28
  29 #define RIO_8_BAD 0
  30 #define RIO_16_BAD (offset & 1)
  31 #define RIO_32_BAD (offset & 3)
  32
  33 /**
  34  * RIO_LOP_READ - Generate rio_local_read_config_* functions
  35  * @size: Size of configuration space read (8, 16, 32 bits)
  36  * @type: C type of value argument
  37  * @len: Length of configuration space read (1, 2, 4 bytes)
  38  *
  39  * Generates rio_local_read_config_* functions used to access
  40  * configuration space registers on the local device.
  41  */
  42 #define RIO_LOP_READ(size,type,len) \
  43 int __rio_local_read_config_##size \
  44         (struct rio_mport *mport, u32 offset, type *value)              \
  45 {                                                                       \
  46         int res;                                                        \
  47         unsigned long flags;                                            \
  48         u32 data = 0;                                                   \
  49         if (RIO_##size##_BAD) return RIO_BAD_SIZE;                      \
  50         spin_lock_irqsave(&rio_config_lock, flags);                     \
  51         res = mport->ops->lcread(mport->id, offset, len, &data);        \
  52         *value = (type)data;                                            \
  53         spin_unlock_irqrestore(&rio_config_lock, flags);                \
  54         return res;                                                     \
  55 }
  56
  57 /**
  58  * RIO_LOP_WRITE - Generate rio_local_write_config_* functions
  59  * @size: Size of configuration space write (8, 16, 32 bits)
  60  * @type: C type of value argument
  61  * @len: Length of configuration space write (1, 2, 4 bytes)
  62  *
  63  * Generates rio_local_write_config_* functions used to access
  64  * configuration space registers on the local device.
  65  */
  66 #define RIO_LOP_WRITE(size,type,len) \
  67 int __rio_local_write_config_##size \
  68         (struct rio_mport *mport, u32 offset, type value)               \
  69 {                                                                       \
  70         int res;                                                        \
  71         unsigned long flags;                                            \
  72         if (RIO_##size##_BAD) return RIO_BAD_SIZE;                      \
  73         spin_lock_irqsave(&rio_config_lock, flags);                     \
  74         res = mport->ops->lcwrite(mport->id, offset, len, value);       \
  75         spin_unlock_irqrestore(&rio_config_lock, flags);                \
  76         return res;                                                     \
  77 }
  78
  79 RIO_LOP_READ(8, u8, 1)
  80 RIO_LOP_READ(16, u16, 2)
  81 RIO_LOP_READ(32, u32, 4)
  82 RIO_LOP_WRITE(8, u8, 1)
  83 RIO_LOP_WRITE(16, u16, 2)
  84 RIO_LOP_WRITE(32, u32, 4)
  85
  86 EXPORT_SYMBOL_GPL(__rio_local_read_config_8);
  87 EXPORT_SYMBOL_GPL(__rio_local_read_config_16);
  88 EXPORT_SYMBOL_GPL(__rio_local_read_config_32);
  89 EXPORT_SYMBOL_GPL(__rio_local_write_config_8);
  90 EXPORT_SYMBOL_GPL(__rio_local_write_config_16);
  91 EXPORT_SYMBOL_GPL(__rio_local_write_config_32);
  92
  93 /**
  94  * RIO_OP_READ - Generate rio_mport_read_config_* functions
  95  * @size: Size of configuration space read (8, 16, 32 bits)
  96  * @type: C type of value argument
  97  * @len: Length of configuration space read (1, 2, 4 bytes)
  98  *
  99  * Generates rio_mport_read_config_* functions used to access
 100  * configuration space registers on the local device.
 101  */
 102 #define RIO_OP_READ(size,type,len) \
 103 int rio_mport_read_config_##size \
 104         (struct rio_mport *mport, u16 destid, u8 hopcount, u32 offset, type *value)     \
 105 {                                                                       \
 106         int res;                                                        \
 107         unsigned long flags;                                            \
 108         u32 data = 0;                                                   \
 109         if (RIO_##size##_BAD) return RIO_BAD_SIZE;                      \
 110         spin_lock_irqsave(&rio_config_lock, flags);                     \
 111         res = mport->ops->cread(mport->id, destid, hopcount, offset, len, &data); \
 112         *value = (type)data;                                            \
 113         spin_unlock_irqrestore(&rio_config_lock, flags);                \
 114         return res;                                                     \
 115 }
 116
 117 /**
 118  * RIO_OP_WRITE - Generate rio_mport_write_config_* functions
 119  * @size: Size of configuration space write (8, 16, 32 bits)
 120  * @type: C type of value argument
 121  * @len: Length of configuration space write (1, 2, 4 bytes)
 122  *
 123  * Generates rio_mport_write_config_* functions used to access
 124  * configuration space registers on the local device.
 125  */
 126 #define RIO_OP_WRITE(size,type,len) \
 127 int rio_mport_write_config_##size \
 128         (struct rio_mport *mport, u16 destid, u8 hopcount, u32 offset, type value)      \
 129 {                                                                       \
 130         int res;                                                        \
 131         unsigned long flags;                                            \
 132         if (RIO_##size##_BAD) return RIO_BAD_SIZE;                      \
 133         spin_lock_irqsave(&rio_config_lock, flags);                     \
 134         res = mport->ops->cwrite(mport->id, destid, hopcount, offset, len, value); \
 135         spin_unlock_irqrestore(&rio_config_lock, flags);                \
 136         return res;                                                     \
 137 }
 138
 139 RIO_OP_READ(8, u8, 1)
 140 RIO_OP_READ(16, u16, 2)
 141 RIO_OP_READ(32, u32, 4)
 142 RIO_OP_WRITE(8, u8, 1)
 143 RIO_OP_WRITE(16, u16, 2)
 144 RIO_OP_WRITE(32, u32, 4)
 145
 146 EXPORT_SYMBOL_GPL(rio_mport_read_config_8);
 147 EXPORT_SYMBOL_GPL(rio_mport_read_config_16);
 148 EXPORT_SYMBOL_GPL(rio_mport_read_config_32);
 149 EXPORT_SYMBOL_GPL(rio_mport_write_config_8);
 150 EXPORT_SYMBOL_GPL(rio_mport_write_config_16);
 151 EXPORT_SYMBOL_GPL(rio_mport_write_config_32);
 152
 153 /**
 154  * rio_mport_send_doorbell - Send a doorbell message
 155  *
 156  * @mport: RIO master port
 157  * @destid: RIO device destination ID
 158  * @data: Doorbell message data
 159  *
 160  * Send a doorbell message to a RIO device. The doorbell message
 161  * has a 16-bit info field provided by the data argument.
 162  */
 163 int rio_mport_send_doorbell(struct rio_mport *mport, u16 destid, u16 data)
 164 {
 165         int res;
 166         unsigned long flags;
 167
 168         spin_lock_irqsave(&rio_doorbell_lock, flags);
 169         res = mport->ops->dsend(mport->id, destid, data);
 170         spin_unlock_irqrestore(&rio_doorbell_lock, flags);
 171
 172         return res;
 173 }
 174
 175 EXPORT_SYMBOL_GPL(rio_mport_send_doorbell);