aboutsummaryrefslogtreecommitdiff
path: root/include/linux/amba/pl08x.h
blob: 0f5b34d668b696809ead862e45edcace882452e1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
/*
 * linux/amba/pl08x.h - ARM PrimeCell DMA Controller driver
 *
 * Copyright (C) 2005 ARM Ltd
 * Copyright (C) 2010 ST-Ericsson SA
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * pl08x information required by platform code
 *
 * Please credit ARM.com
 * Documentation: ARM DDI 0196D
 */

#ifndef AMBA_PL08X_H
#define AMBA_PL08X_H

/* We need sizes of structs from this header */
#include <linux/dmaengine.h>
#include <linux/interrupt.h>

struct pl08x_lli;
struct pl08x_driver_data;

/* Bitmasks for selecting AHB ports for DMA transfers */
enum {
	PL08X_AHB1 = (1 << 0),
	PL08X_AHB2 = (1 << 1)
};

/**
 * struct pl08x_channel_data - data structure to pass info between
 * platform and PL08x driver regarding channel configuration
 * @bus_id: name of this device channel, not just a device name since
 * devices may have more than one channel e.g. "foo_tx"
 * @min_signal: the minimum DMA signal number to be muxed in for this
 * channel (for platforms supporting muxed signals). If you have
 * static assignments, make sure this is set to the assigned signal
 * number, PL08x have 16 possible signals in number 0 thru 15 so
 * when these are not enough they often get muxed (in hardware)
 * disabling simultaneous use of the same channel for two devices.
 * @max_signal: the maximum DMA signal number to be muxed in for
 * the channel. Set to the same as min_signal for
 * devices with static assignments
 * @muxval: a number usually used to poke into some mux regiser to
 * mux in the signal to this channel
 * @cctl_opt: default options for the channel control register
 * @addr: source/target address in physical memory for this DMA channel,
 * can be the address of a FIFO register for burst requests for example.
 * This can be left undefined if the PrimeCell API is used for configuring
 * this.
 * @single: the device connected to this channel will request single DMA
 * transfers, not bursts. (Bursts are default.)
 * @periph_buses: the device connected to this channel is accessible via
 * these buses (use PL08X_AHB1 | PL08X_AHB2).
 */
struct pl08x_channel_data {
	char *bus_id;
	int min_signal;
	int max_signal;
	u32 muxval;
	u32 cctl;
	dma_addr_t addr;
	bool single;
	u8 periph_buses;
};

/**
 * Struct pl08x_bus_data - information of source or destination
 * busses for a transfer
 * @addr: current address
 * @maxwidth: the maximum width of a transfer on this bus
 * @buswidth: the width of this bus in bytes: 1, 2 or 4
 */
struct pl08x_bus_data {
	dma_addr_t addr;
	u8 maxwidth;
	u8 buswidth;
};

/**
 * struct pl08x_phy_chan - holder for the physical channels
 * @id: physical index to this channel
 * @lock: a lock to use when altering an instance of this struct
 * @signal: the physical signal (aka channel) serving this physical channel
 * right now
 * @serving: the virtual channel currently being served by this physical
 * channel
 * @locked: channel unavailable for the system, e.g. dedicated to secure
 * world
 */
struct pl08x_phy_chan {
	unsigned int id;
	void __iomem *base;
	spinlock_t lock;
	int signal;
	struct pl08x_dma_chan *serving;
	bool locked;
};

/**
 * struct pl08x_sg - structure containing data per sg
 * @src_addr: src address of sg
 * @dst_addr: dst address of sg
 * @len: transfer len in bytes
 * @node: node for txd's dsg_list
 */
struct pl08x_sg {
	dma_addr_t src_addr;
	dma_addr_t dst_addr;
	size_t len;
	struct list_head node;
};

/**
 * struct pl08x_txd - wrapper for struct dma_async_tx_descriptor
 * @tx: async tx descriptor
 * @node: node for txd list for channels
 * @dsg_list: list of children sg's
 * @direction: direction of transfer
 * @llis_bus: DMA memory address (physical) start for the LLIs
 * @llis_va: virtual memory address start for the LLIs
 * @cctl: control reg values for current txd
 * @ccfg: config reg values for current txd
 */
struct pl08x_txd {
	struct dma_async_tx_descriptor tx;
	struct list_head node;
	struct list_head dsg_list;
	enum dma_transfer_direction direction;
	dma_addr_t llis_bus;
	struct pl08x_lli *llis_va;
	/* Default cctl value for LLIs */
	u32 cctl;
	/*
	 * Settings to be put into the physical channel when we
	 * trigger this txd.  Other registers are in llis_va[0].
	 */
	u32 ccfg;
};

/**
 * struct pl08x_dma_chan_state - holds the PL08x specific virtual channel
 * states
 * @PL08X_CHAN_IDLE: the channel is idle
 * @PL08X_CHAN_RUNNING: the channel has allocated a physical transport
 * channel and is running a transfer on it
 * @PL08X_CHAN_PAUSED: the channel has allocated a physical transport
 * channel, but the transfer is currently paused
 * @PL08X_CHAN_WAITING: the channel is waiting for a physical transport
 * channel to become available (only pertains to memcpy channels)
 */
enum pl08x_dma_chan_state {
	PL08X_CHAN_IDLE,
	PL08X_CHAN_RUNNING,
	PL08X_CHAN_PAUSED,
	PL08X_CHAN_WAITING,
};

/**
 * struct pl08x_dma_chan - this structure wraps a DMA ENGINE channel
 * @chan: wrappped abstract channel
 * @phychan: the physical channel utilized by this channel, if there is one
 * @phychan_hold: if non-zero, hold on to the physical channel even if we
 * have no pending entries
 * @tasklet: tasklet scheduled by the IRQ to handle actual work etc
 * @name: name of channel
 * @cd: channel platform data
 * @runtime_addr: address for RX/TX according to the runtime config
 * @runtime_direction: current direction of this channel according to
 * runtime config
 * @pend_list: queued transactions pending on this channel
 * @at: active transaction on this channel
 * @lock: a lock for this channel data
 * @host: a pointer to the host (internal use)
 * @state: whether the channel is idle, paused, running etc
 * @slave: whether this channel is a device (slave) or for memcpy
 * @device_fc: Flow Controller Settings for ccfg register. Only valid for slave
 * channels. Fill with 'true' if peripheral should be flow controller. Direction
 * will be selected at Runtime.
 * @waiting: a TX descriptor on this channel which is waiting for a physical
 * channel to become available
 */
struct pl08x_dma_chan {
	struct dma_chan chan;
	struct pl08x_phy_chan *phychan;
	int phychan_hold;
	struct tasklet_struct tasklet;
	char *name;
	const struct pl08x_channel_data *cd;
	dma_addr_t src_addr;
	dma_addr_t dst_addr;
	u32 src_cctl;
	u32 dst_cctl;
	enum dma_transfer_direction runtime_direction;
	struct list_head pend_list;
	struct pl08x_txd *at;
	spinlock_t lock;
	struct pl08x_driver_data *host;
	enum pl08x_dma_chan_state state;
	bool slave;
	bool device_fc;
	struct pl08x_txd *waiting;
};

/**
 * struct pl08x_platform_data - the platform configuration for the PL08x
 * PrimeCells.
 * @slave_channels: the channels defined for the different devices on the
 * platform, all inclusive, including multiplexed channels. The available
 * physical channels will be multiplexed around these signals as they are
 * requested, just enumerate all possible channels.
 * @get_signal: request a physical signal to be used for a DMA transfer
 * immediately: if there is some multiplexing or similar blocking the use
 * of the channel the transfer can be denied by returning less than zero,
 * else it returns the allocated signal number
 * @put_signal: indicate to the platform that this physical signal is not
 * running any DMA transfer and multiplexing can be recycled
 * @lli_buses: buses which LLIs can be fetched from: PL08X_AHB1 | PL08X_AHB2
 * @mem_buses: buses which memory can be accessed from: PL08X_AHB1 | PL08X_AHB2
 */
struct pl08x_platform_data {
	const struct pl08x_channel_data *slave_channels;
	unsigned int num_slave_channels;
	struct pl08x_channel_data memcpy_channel;
	int (*get_signal)(struct pl08x_dma_chan *);
	void (*put_signal)(struct pl08x_dma_chan *);
	u8 lli_buses;
	u8 mem_buses;
};

#ifdef CONFIG_AMBA_PL08X
bool pl08x_filter_id(struct dma_chan *chan, void *chan_id);
#else
static inline bool pl08x_filter_id(struct dma_chan *chan, void *chan_id)
{
	return false;
}
#endif

#endif	/* AMBA_PL08X_H */