4 * kernel ISO transmission/reception
6 * Copyright (C) 2002 Maas Digital LLC
8 * This code is licensed under the GPL. See the file COPYING in the root
9 * directory of the kernel sources for details.
12 #ifndef IEEE1394_ISO_H
13 #define IEEE1394_ISO_H
18 /* high-level ISO interface */
21 * This API sends and receives isochronous packets on a large,
22 * virtually-contiguous kernel memory buffer. The buffer may be mapped
23 * into a user-space process for zero-copy transmission and reception.
25 * There are no explicit boundaries between packets in the buffer. A
26 * packet may be transmitted or received at any location. However,
27 * low-level drivers may impose certain restrictions on alignment or
28 * size of packets. (e.g. in OHCI no packet may cross a page boundary,
29 * and packets should be quadlet-aligned)
32 /* Packet descriptor - the API maintains a ring buffer of these packet
33 * descriptors in kernel memory (hpsb_iso.infos[]). */
34 struct hpsb_iso_packet_info {
35 /* offset of data payload relative to the first byte of the buffer */
38 /* length of the data payload, in bytes (not including the isochronous
42 /* (recv only) the cycle number (mod 8000) on which the packet was
46 /* (recv only) channel on which the packet was received */
49 /* 2-bit 'tag' and 4-bit 'sy' fields of the isochronous header */
53 /* length in bytes of the packet including header/trailer.
54 * MUST be at structure end, since the first part of this structure is
55 * also defined in raw1394.h (i.e. struct raw1394_iso_packet_info), is
56 * copied to userspace and is accessed there through libraw1394. */
60 enum hpsb_iso_type { HPSB_ISO_RECV = 0, HPSB_ISO_XMIT = 1 };
62 /* The mode of the dma when receiving iso data. Must be supported by chip */
63 enum raw1394_iso_dma_recv_mode {
64 HPSB_ISO_DMA_DEFAULT = -1,
65 HPSB_ISO_DMA_OLD_ABI = 0,
66 HPSB_ISO_DMA_BUFFERFILL = 1,
67 HPSB_ISO_DMA_PACKET_PER_BUFFER = 2
71 enum hpsb_iso_type type;
73 /* pointer to low-level driver and its private data */
74 struct hpsb_host *host;
77 /* a function to be called (from interrupt context) after
78 * outgoing packets have been sent, or incoming packets have
80 void (*callback)(struct hpsb_iso*);
82 /* wait for buffer space */
83 wait_queue_head_t waitq;
85 int speed; /* IEEE1394_SPEED_100, 200, or 400 */
86 int channel; /* -1 if multichannel */
87 int dma_mode; /* dma receive mode */
90 /* greatest # of packets between interrupts - controls
91 * the maximum latency of the buffer */
94 /* the buffer for packet data payloads */
95 struct dma_region data_buf;
97 /* size of data_buf, in bytes (always a multiple of PAGE_SIZE) */
98 unsigned int buf_size;
100 /* # of packets in the ringbuffer */
101 unsigned int buf_packets;
103 /* protects packet cursors */
106 /* the index of the next packet that will be produced
107 or consumed by the user */
110 /* the index of the next packet that will be transmitted
111 or received by the 1394 hardware */
114 /* how many packets, starting at first_packet:
115 * (transmit) are ready to be filled with data
116 * (receive) contain received data */
119 /* how many times the buffer has overflowed or underflowed */
122 /* Current number of bytes lost in discarded packets */
125 /* private flags to track initialization progress */
126 #define HPSB_ISO_DRIVER_INIT (1<<0)
127 #define HPSB_ISO_DRIVER_STARTED (1<<1)
130 /* # of packets left to prebuffer (xmit only) */
133 /* starting cycle for DMA (xmit only) */
136 /* cycle at which next packet will be transmitted,
140 /* ringbuffer of packet descriptors in regular kernel memory
141 * XXX Keep this last, since we use over-allocated memory from
142 * this entry to fill this field. */
143 struct hpsb_iso_packet_info *infos;
146 /* functions available to high-level drivers (e.g. raw1394) */
148 /* allocate the buffer and DMA context */
150 struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,
151 unsigned int data_buf_size,
152 unsigned int buf_packets,
156 void (*callback)(struct hpsb_iso*));
158 /* note: if channel = -1, multi-channel receive is enabled */
159 struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
160 unsigned int data_buf_size,
161 unsigned int buf_packets,
165 void (*callback)(struct hpsb_iso*));
167 /* multi-channel only */
168 int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel);
169 int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel);
170 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,
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);
179 /* deallocate buffer and DMA context */
180 void hpsb_iso_shutdown(struct hpsb_iso *iso);
182 /* queue a packet for transmission.
183 * 'offset' is relative to the beginning of the DMA buffer, where the packet's
184 * data payload should already have been placed. */
185 int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len,
188 /* wait until all queued packets have been transmitted to the bus */
189 int hpsb_iso_xmit_sync(struct hpsb_iso *iso);
191 /* N packets have been read out of the buffer, re-use the buffer space */
192 int hpsb_iso_recv_release_packets(struct hpsb_iso *recv,
193 unsigned int n_packets);
195 /* check for arrival of new packets immediately (even if irq_interval
196 * has not yet been reached) */
197 int hpsb_iso_recv_flush(struct hpsb_iso *iso);
199 /* returns # of packets ready to send or receive */
200 int hpsb_iso_n_ready(struct hpsb_iso *iso);
202 /* the following are callbacks available to low-level drivers */
204 /* call after a packet has been transmitted to the bus (interrupt context is OK)
205 * 'cycle' is the _exact_ cycle the packet was sent on
206 * 'error' should be non-zero if some sort of error occurred when sending the
208 void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error);
210 /* call after a packet has been received (interrupt context OK) */
211 void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
212 u16 total_len, u16 cycle, u8 channel, u8 tag,
215 /* call to wake waiting processes after buffer space has opened up. */
216 void hpsb_iso_wake(struct hpsb_iso *iso);
218 #endif /* IEEE1394_ISO_H */