1 /*
2 * IEEE 1394 for Linux
3 *
4 * kernel ISO transmission/reception
5 *
6 * Copyright (C) 2002 Maas Digital LLC
7 *
8 * This code is licensed under the GPL. See the file COPYING in the root
9 * directory of the kernel sources for details.
10 */
11
12 #ifndef IEEE1394_ISO_H
13 #define IEEE1394_ISO_H
14
15 #include <linux/spinlock_types.h>
16 #include <linux/wait.h>
17 #include <asm/atomic.h>
18 #include <asm/types.h>
19
20 #include "dma.h"
21
22 struct hpsb_host;
23
24 /* high-level ISO interface */
25
26 /*
27 * This API sends and receives isochronous packets on a large,
28 * virtually-contiguous kernel memory buffer. The buffer may be mapped
29 * into a user-space process for zero-copy transmission and reception.
30 *
31 * There are no explicit boundaries between packets in the buffer. A
32 * packet may be transmitted or received at any location. However,
33 * low-level drivers may impose certain restrictions on alignment or
34 * size of packets. (e.g. in OHCI no packet may cross a page boundary,
35 * and packets should be quadlet-aligned)
36 */
37
38 /* Packet descriptor - the API maintains a ring buffer of these packet
39 * descriptors in kernel memory (hpsb_iso.infos[]). */
40 struct hpsb_iso_packet_info {
41 /* offset of data payload relative to the first byte of the buffer */
42 __u32 offset;
43
44 /* length of the data payload, in bytes (not including the isochronous
45 * header) */
46 __u16 len;
47
48 /* (recv only) the cycle number (mod 8000) on which the packet was
49 * received */
50 __u16 cycle;
51
52 /* (recv only) channel on which the packet was received */
53 __u8 channel;
54
55 /* 2-bit 'tag' and 4-bit 'sy' fields of the isochronous header */
56 __u8 tag;
57 __u8 sy;
58
59 /* length in bytes of the packet including header/trailer.
60 * MUST be at structure end, since the first part of this structure is
61 * also defined in raw1394.h (i.e. struct raw1394_iso_packet_info), is
62 * copied to userspace and is accessed there through libraw1394. */
63 __u16 total_len;
64 };
65
66 enum hpsb_iso_type { HPSB_ISO_RECV = 0, HPSB_ISO_XMIT = 1 };
67
68 /* The mode of the dma when receiving iso data. Must be supported by chip */
69 enum raw1394_iso_dma_recv_mode {
70 HPSB_ISO_DMA_DEFAULT = -1,
71 HPSB_ISO_DMA_OLD_ABI = 0,
72 HPSB_ISO_DMA_BUFFERFILL = 1,
73 HPSB_ISO_DMA_PACKET_PER_BUFFER = 2
74 };
75
76 struct hpsb_iso {
77 enum hpsb_iso_type type;
78
79 /* pointer to low-level driver and its private data */
80 struct hpsb_host *host;
81 void *hostdata;
82
83 /* a function to be called (from interrupt context) after
84 * outgoing packets have been sent, or incoming packets have
85 * arrived */
86 void (*callback)(struct hpsb_iso*);
87
88 /* wait for buffer space */
89 wait_queue_head_t waitq;
90
91 int speed; /* IEEE1394_SPEED_100, 200, or 400 */
92 int channel; /* -1 if multichannel */
93 int dma_mode; /* dma receive mode */
94
95
96 /* greatest # of packets between interrupts - controls
97 * the maximum latency of the buffer */
98 int irq_interval;
99
100 /* the buffer for packet data payloads */
101 struct dma_region data_buf;
102
103 /* size of data_buf, in bytes (always a multiple of PAGE_SIZE) */
104 unsigned int buf_size;
105
106 /* # of packets in the ringbuffer */
107 unsigned int buf_packets;
108
109 /* protects packet cursors */
110 spinlock_t lock;
111
112 /* the index of the next packet that will be produced
113 or consumed by the user */
114 int first_packet;
115
116 /* the index of the next packet that will be transmitted
117 or received by the 1394 hardware */
118 int pkt_dma;
119
120 /* how many packets, starting at first_packet:
121 * (transmit) are ready to be filled with data
122 * (receive) contain received data */
123 int n_ready_packets;
124
125 /* how many times the buffer has overflowed or underflowed */
126 atomic_t overflows;
127 /* how many cycles were skipped for a given context */
128 atomic_t skips;
129
130 /* Current number of bytes lost in discarded packets */
131 int bytes_discarded;
132
133 /* private flags to track initialization progress */
134 #define HPSB_ISO_DRIVER_INIT (1<<0)
135 #define HPSB_ISO_DRIVER_STARTED (1<<1)
136 unsigned int flags;
137
138 /* # of packets left to prebuffer (xmit only) */
139 int prebuffer;
140
141 /* starting cycle for DMA (xmit only) */
142 int start_cycle;
143
144 /* cycle at which next packet will be transmitted,
145 * -1 if not known */
146 int xmit_cycle;
147
148 /* ringbuffer of packet descriptors in regular kernel memory
149 * XXX Keep this last, since we use over-allocated memory from
150 * this entry to fill this field. */
151 struct hpsb_iso_packet_info *infos;
152 };
153
154 /* functions available to high-level drivers (e.g. raw1394) */
155
156 struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,
157 unsigned int data_buf_size,
158 unsigned int buf_packets,
159 int channel,
160 int speed,
161 int irq_interval,
162 void (*callback)(struct hpsb_iso*));
163 struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
164 unsigned int data_buf_size,
165 unsigned int buf_packets,
166 int channel,
167 int dma_mode,
168 int irq_interval,
169 void (*callback)(struct hpsb_iso*));
170 int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel);
171 int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel);
172 int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask);
173 int hpsb_iso_xmit_start(struct hpsb_iso *iso, int start_on_cycle,
174 int prebuffer);
175 int hpsb_iso_recv_start(struct hpsb_iso *iso, int start_on_cycle,
176 int tag_mask, int sync);
177 void hpsb_iso_stop(struct hpsb_iso *iso);
178 void hpsb_iso_shutdown(struct hpsb_iso *iso);
179 int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len,
180 u8 tag, u8 sy);
181 int hpsb_iso_xmit_sync(struct hpsb_iso *iso);
182 int hpsb_iso_recv_release_packets(struct hpsb_iso *recv,
183 unsigned int n_packets);
184 int hpsb_iso_recv_flush(struct hpsb_iso *iso);
185 int hpsb_iso_n_ready(struct hpsb_iso *iso);
186
187 /* the following are callbacks available to low-level drivers */
188
189 void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error);
190 void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
191 u16 total_len, u16 cycle, u8 channel, u8 tag,
192 u8 sy);
193 void hpsb_iso_wake(struct hpsb_iso *iso);
194
195 #endif /* IEEE1394_ISO_H */
196
|
This page was automatically generated by the
LXR engine.
|