include/linux/amba/pl08x.h

   1 /*
   2  * linux/amba/pl08x.h - ARM PrimeCell DMA Controller driver
   3  *
   4  * Copyright (C) 2005 ARM Ltd
   5  * Copyright (C) 2010 ST-Ericsson SA
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * pl08x information required by platform code
  12  *
  13  * Please credit ARM.com
  14  * Documentation: ARM DDI 0196D
  15  */
  16
  17 #ifndef AMBA_PL08X_H
  18 #define AMBA_PL08X_H
  19
  20 /* We need sizes of structs from this header */
  21 #include <linux/dmaengine.h>
  22 #include <linux/interrupt.h>
  23
  24 struct pl08x_driver_data;
  25 struct pl08x_phy_chan;
  26 struct pl08x_txd;
  27
  28 /* Bitmasks for selecting AHB ports for DMA transfers */
  29 enum {
  30         PL08X_AHB1 = (1 << 0),
  31         PL08X_AHB2 = (1 << 1)
  32 };
  33
  34 /**
  35  * struct pl08x_channel_data - data structure to pass info between
  36  * platform and PL08x driver regarding channel configuration
  37  * @bus_id: name of this device channel, not just a device name since
  38  * devices may have more than one channel e.g. "foo_tx"
  39  * @min_signal: the minimum DMA signal number to be muxed in for this
  40  * channel (for platforms supporting muxed signals). If you have
  41  * static assignments, make sure this is set to the assigned signal
  42  * number, PL08x have 16 possible signals in number 0 thru 15 so
  43  * when these are not enough they often get muxed (in hardware)
  44  * disabling simultaneous use of the same channel for two devices.
  45  * @max_signal: the maximum DMA signal number to be muxed in for
  46  * the channel. Set to the same as min_signal for
  47  * devices with static assignments
  48  * @muxval: a number usually used to poke into some mux regiser to
  49  * mux in the signal to this channel
  50  * @cctl_memcpy: options for the channel control register for memcpy
  51  *  *** not used for slave channels ***
  52  * @addr: source/target address in physical memory for this DMA channel,
  53  * can be the address of a FIFO register for burst requests for example.
  54  * This can be left undefined if the PrimeCell API is used for configuring
  55  * this.
  56  * @single: the device connected to this channel will request single DMA
  57  * transfers, not bursts. (Bursts are default.)
  58  * @periph_buses: the device connected to this channel is accessible via
  59  * these buses (use PL08X_AHB1 | PL08X_AHB2).
  60  */
  61 struct pl08x_channel_data {
  62         const char *bus_id;
  63         int min_signal;
  64         int max_signal;
  65         u32 muxval;
  66         u32 cctl_memcpy;
  67         dma_addr_t addr;
  68         bool single;
  69         u8 periph_buses;
  70 };
  71
  72 /**
  73  * struct pl08x_platform_data - the platform configuration for the PL08x
  74  * PrimeCells.
  75  * @slave_channels: the channels defined for the different devices on the
  76  * platform, all inclusive, including multiplexed channels. The available
  77  * physical channels will be multiplexed around these signals as they are
  78  * requested, just enumerate all possible channels.
  79  * @get_signal: request a physical signal to be used for a DMA transfer
  80  * immediately: if there is some multiplexing or similar blocking the use
  81  * of the channel the transfer can be denied by returning less than zero,
  82  * else it returns the allocated signal number
  83  * @put_signal: indicate to the platform that this physical signal is not
  84  * running any DMA transfer and multiplexing can be recycled
  85  * @lli_buses: buses which LLIs can be fetched from: PL08X_AHB1 | PL08X_AHB2
  86  * @mem_buses: buses which memory can be accessed from: PL08X_AHB1 | PL08X_AHB2
  87  */
  88 struct pl08x_platform_data {
  89         const struct pl08x_channel_data *slave_channels;
  90         unsigned int num_slave_channels;
  91         struct pl08x_channel_data memcpy_channel;
  92         int (*get_signal)(const struct pl08x_channel_data *);
  93         void (*put_signal)(const struct pl08x_channel_data *, int);
  94         u8 lli_buses;
  95         u8 mem_buses;
  96 };
  97
  98 #ifdef CONFIG_AMBA_PL08X
  99 bool pl08x_filter_id(struct dma_chan *chan, void *chan_id);
 100 #else
 101 static inline bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
 102 {
 103         return false;
 104 }
 105 #endif
 106
 107 #endif  /* AMBA_PL08X_H */