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 22struct 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[]). */ 40struct 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 66enum 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 */ 69enum 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 76struct 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 struct hpsb_iso_packet_info *infos; 149}; 150 151/* functions available to high-level drivers (e.g. raw1394) */ 152 153struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host, 154 unsigned int data_buf_size, 155 unsigned int buf_packets, 156 int channel, 157 int speed, 158 int irq_interval, 159 void (*callback)(struct hpsb_iso*)); 160struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host, 161 unsigned int data_buf_size, 162 unsigned int buf_packets, 163 int channel, 164 int dma_mode, 165 int irq_interval, 166 void (*callback)(struct hpsb_iso*)); 167int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel); 168int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel); 169int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask); 170int hpsb_iso_xmit_start(struct hpsb_iso *iso, int start_on_cycle, 171 int prebuffer); 172int hpsb_iso_recv_start(struct hpsb_iso *iso, int start_on_cycle, 173 int tag_mask, int sync); 174void hpsb_iso_stop(struct hpsb_iso *iso); 175void hpsb_iso_shutdown(struct hpsb_iso *iso); 176int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, 177 u8 tag, u8 sy); 178int hpsb_iso_xmit_sync(struct hpsb_iso *iso); 179int hpsb_iso_recv_release_packets(struct hpsb_iso *recv, 180 unsigned int n_packets); 181int hpsb_iso_recv_flush(struct hpsb_iso *iso); 182int hpsb_iso_n_ready(struct hpsb_iso *iso); 183 184/* the following are callbacks available to low-level drivers */ 185 186void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error); 187void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len, 188 u16 total_len, u16 cycle, u8 channel, u8 tag, 189 u8 sy); 190void hpsb_iso_wake(struct hpsb_iso *iso); 191 192#endif /* IEEE1394_ISO_H */ 193