xref: /linux/include/linux/amba/pl08x.h (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   * linux/amba/pl08x.h - ARM PrimeCell DMA Controller driver
4   *
5   * Copyright (C) 2005 ARM Ltd
6   * Copyright (C) 2010 ST-Ericsson SA
7   *
8   * pl08x information required by platform code
9   *
10   * Please credit ARM.com
11   * Documentation: ARM DDI 0196D
12   */
13  
14  #ifndef AMBA_PL08X_H
15  #define AMBA_PL08X_H
16  
17  /* We need sizes of structs from this header */
18  #include <linux/dmaengine.h>
19  #include <linux/interrupt.h>
20  
21  struct pl08x_driver_data;
22  struct pl08x_phy_chan;
23  struct pl08x_txd;
24  
25  /* Bitmasks for selecting AHB ports for DMA transfers */
26  enum {
27  	PL08X_AHB1 = (1 << 0),
28  	PL08X_AHB2 = (1 << 1)
29  };
30  
31  /**
32   * struct pl08x_channel_data - data structure to pass info between
33   * platform and PL08x driver regarding channel configuration
34   * @bus_id: name of this device channel, not just a device name since
35   * devices may have more than one channel e.g. "foo_tx"
36   * @min_signal: the minimum DMA signal number to be muxed in for this
37   * channel (for platforms supporting muxed signals). If you have
38   * static assignments, make sure this is set to the assigned signal
39   * number, PL08x have 16 possible signals in number 0 thru 15 so
40   * when these are not enough they often get muxed (in hardware)
41   * disabling simultaneous use of the same channel for two devices.
42   * @max_signal: the maximum DMA signal number to be muxed in for
43   * the channel. Set to the same as min_signal for
44   * devices with static assignments
45   * @muxval: a number usually used to poke into some mux regiser to
46   * mux in the signal to this channel
47   * @addr: source/target address in physical memory for this DMA channel,
48   * can be the address of a FIFO register for burst requests for example.
49   * This can be left undefined if the PrimeCell API is used for configuring
50   * this.
51   * @single: the device connected to this channel will request single DMA
52   * transfers, not bursts. (Bursts are default.)
53   * @periph_buses: the device connected to this channel is accessible via
54   * these buses (use PL08X_AHB1 | PL08X_AHB2).
55   */
56  struct pl08x_channel_data {
57  	const char *bus_id;
58  	int min_signal;
59  	int max_signal;
60  	u32 muxval;
61  	dma_addr_t addr;
62  	bool single;
63  	u8 periph_buses;
64  };
65  
66  enum pl08x_burst_size {
67  	PL08X_BURST_SZ_1,
68  	PL08X_BURST_SZ_4,
69  	PL08X_BURST_SZ_8,
70  	PL08X_BURST_SZ_16,
71  	PL08X_BURST_SZ_32,
72  	PL08X_BURST_SZ_64,
73  	PL08X_BURST_SZ_128,
74  	PL08X_BURST_SZ_256,
75  };
76  
77  enum pl08x_bus_width {
78  	PL08X_BUS_WIDTH_8_BITS,
79  	PL08X_BUS_WIDTH_16_BITS,
80  	PL08X_BUS_WIDTH_32_BITS,
81  };
82  
83  /**
84   * struct pl08x_platform_data - the platform configuration for the PL08x
85   * PrimeCells.
86   * @slave_channels: the channels defined for the different devices on the
87   * platform, all inclusive, including multiplexed channels. The available
88   * physical channels will be multiplexed around these signals as they are
89   * requested, just enumerate all possible channels.
90   * @num_slave_channels: number of elements in the slave channel array
91   * @memcpy_burst_size: the appropriate burst size for memcpy operations
92   * @memcpy_bus_width: memory bus width
93   * @memcpy_prot_buff: whether memcpy DMA is bufferable
94   * @memcpy_prot_cache: whether memcpy DMA is cacheable
95   * @get_xfer_signal: request a physical signal to be used for a DMA transfer
96   * immediately: if there is some multiplexing or similar blocking the use
97   * of the channel the transfer can be denied by returning less than zero,
98   * else it returns the allocated signal number
99   * @put_xfer_signal: indicate to the platform that this physical signal is not
100   * running any DMA transfer and multiplexing can be recycled
101   * @lli_buses: buses which LLIs can be fetched from: PL08X_AHB1 | PL08X_AHB2
102   * @mem_buses: buses which memory can be accessed from: PL08X_AHB1 | PL08X_AHB2
103   * @slave_map: DMA slave matching table
104   * @slave_map_len: number of elements in @slave_map
105   */
106  struct pl08x_platform_data {
107  	struct pl08x_channel_data *slave_channels;
108  	unsigned int num_slave_channels;
109  	enum pl08x_burst_size memcpy_burst_size;
110  	enum pl08x_bus_width memcpy_bus_width;
111  	bool memcpy_prot_buff;
112  	bool memcpy_prot_cache;
113  	int (*get_xfer_signal)(const struct pl08x_channel_data *);
114  	void (*put_xfer_signal)(const struct pl08x_channel_data *, int);
115  	u8 lli_buses;
116  	u8 mem_buses;
117  	const struct dma_slave_map *slave_map;
118  	int slave_map_len;
119  };
120  
121  #ifdef CONFIG_AMBA_PL08X
122  bool pl08x_filter_id(struct dma_chan *chan, void *chan_id);
123  #else
pl08x_filter_id(struct dma_chan * chan,void * chan_id)124  static inline bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
125  {
126  	return false;
127  }
128  #endif
129  
130  #endif	/* AMBA_PL08X_H */
131