| /* |
| * IEEE 1394 for Linux |
| * |
| * kernel ISO transmission/reception |
| * |
| * Copyright (C) 2002 Maas Digital LLC |
| * |
| * This code is licensed under the GPL. See the file COPYING in the root |
| * directory of the kernel sources for details. |
| */ |
| |
| #ifndef IEEE1394_ISO_H |
| #define IEEE1394_ISO_H |
| |
| #include "hosts.h" |
| #include "dma.h" |
| |
| /* high-level ISO interface */ |
| |
| /* |
| * This API sends and receives isochronous packets on a large, |
| * virtually-contiguous kernel memory buffer. The buffer may be mapped |
| * into a user-space process for zero-copy transmission and reception. |
| * |
| * There are no explicit boundaries between packets in the buffer. A |
| * packet may be transmitted or received at any location. However, |
| * low-level drivers may impose certain restrictions on alignment or |
| * size of packets. (e.g. in OHCI no packet may cross a page boundary, |
| * and packets should be quadlet-aligned) |
| */ |
| |
| /* Packet descriptor - the API maintains a ring buffer of these packet |
| * descriptors in kernel memory (hpsb_iso.infos[]). */ |
| struct hpsb_iso_packet_info { |
| /* offset of data payload relative to the first byte of the buffer */ |
| __u32 offset; |
| |
| /* length of the data payload, in bytes (not including the isochronous |
| * header) */ |
| __u16 len; |
| |
| /* (recv only) the cycle number (mod 8000) on which the packet was |
| * received */ |
| __u16 cycle; |
| |
| /* (recv only) channel on which the packet was received */ |
| __u8 channel; |
| |
| /* 2-bit 'tag' and 4-bit 'sy' fields of the isochronous header */ |
| __u8 tag; |
| __u8 sy; |
| |
| /* length in bytes of the packet including header/trailer. |
| * MUST be at structure end, since the first part of this structure is |
| * also defined in raw1394.h (i.e. struct raw1394_iso_packet_info), is |
| * copied to userspace and is accessed there through libraw1394. */ |
| __u16 total_len; |
| }; |
| |
| enum hpsb_iso_type { HPSB_ISO_RECV = 0, HPSB_ISO_XMIT = 1 }; |
| |
| /* The mode of the dma when receiving iso data. Must be supported by chip */ |
| enum raw1394_iso_dma_recv_mode { |
| HPSB_ISO_DMA_DEFAULT = -1, |
| HPSB_ISO_DMA_OLD_ABI = 0, |
| HPSB_ISO_DMA_BUFFERFILL = 1, |
| HPSB_ISO_DMA_PACKET_PER_BUFFER = 2 |
| }; |
| |
| struct hpsb_iso { |
| enum hpsb_iso_type type; |
| |
| /* pointer to low-level driver and its private data */ |
| struct hpsb_host *host; |
| void *hostdata; |
| |
| /* a function to be called (from interrupt context) after |
| * outgoing packets have been sent, or incoming packets have |
| * arrived */ |
| void (*callback)(struct hpsb_iso*); |
| |
| /* wait for buffer space */ |
| wait_queue_head_t waitq; |
| |
| int speed; /* IEEE1394_SPEED_100, 200, or 400 */ |
| int channel; /* -1 if multichannel */ |
| int dma_mode; /* dma receive mode */ |
| |
| |
| /* greatest # of packets between interrupts - controls |
| * the maximum latency of the buffer */ |
| int irq_interval; |
| |
| /* the buffer for packet data payloads */ |
| struct dma_region data_buf; |
| |
| /* size of data_buf, in bytes (always a multiple of PAGE_SIZE) */ |
| unsigned int buf_size; |
| |
| /* # of packets in the ringbuffer */ |
| unsigned int buf_packets; |
| |
| /* protects packet cursors */ |
| spinlock_t lock; |
| |
| /* the index of the next packet that will be produced |
| or consumed by the user */ |
| int first_packet; |
| |
| /* the index of the next packet that will be transmitted |
| or received by the 1394 hardware */ |
| int pkt_dma; |
| |
| /* how many packets, starting at first_packet: |
| * (transmit) are ready to be filled with data |
| * (receive) contain received data */ |
| int n_ready_packets; |
| |
| /* how many times the buffer has overflowed or underflowed */ |
| atomic_t overflows; |
| |
| /* Current number of bytes lost in discarded packets */ |
| int bytes_discarded; |
| |
| /* private flags to track initialization progress */ |
| #define HPSB_ISO_DRIVER_INIT (1<<0) |
| #define HPSB_ISO_DRIVER_STARTED (1<<1) |
| unsigned int flags; |
| |
| /* # of packets left to prebuffer (xmit only) */ |
| int prebuffer; |
| |
| /* starting cycle for DMA (xmit only) */ |
| int start_cycle; |
| |
| /* cycle at which next packet will be transmitted, |
| * -1 if not known */ |
| int xmit_cycle; |
| |
| /* ringbuffer of packet descriptors in regular kernel memory |
| * XXX Keep this last, since we use over-allocated memory from |
| * this entry to fill this field. */ |
| struct hpsb_iso_packet_info *infos; |
| }; |
| |
| /* functions available to high-level drivers (e.g. raw1394) */ |
| |
| /* allocate the buffer and DMA context */ |
| |
| struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host, |
| unsigned int data_buf_size, |
| unsigned int buf_packets, |
| int channel, |
| int speed, |
| int irq_interval, |
| void (*callback)(struct hpsb_iso*)); |
| |
| /* note: if channel = -1, multi-channel receive is enabled */ |
| struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host, |
| unsigned int data_buf_size, |
| unsigned int buf_packets, |
| int channel, |
| int dma_mode, |
| int irq_interval, |
| void (*callback)(struct hpsb_iso*)); |
| |
| /* multi-channel only */ |
| int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel); |
| int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel); |
| int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask); |
| |
| /* start/stop DMA */ |
| int hpsb_iso_xmit_start(struct hpsb_iso *iso, int start_on_cycle, |
| int prebuffer); |
| int hpsb_iso_recv_start(struct hpsb_iso *iso, int start_on_cycle, |
| int tag_mask, int sync); |
| void hpsb_iso_stop(struct hpsb_iso *iso); |
| |
| /* deallocate buffer and DMA context */ |
| void hpsb_iso_shutdown(struct hpsb_iso *iso); |
| |
| /* queue a packet for transmission. |
| * 'offset' is relative to the beginning of the DMA buffer, where the packet's |
| * data payload should already have been placed. */ |
| int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, |
| u8 tag, u8 sy); |
| |
| /* wait until all queued packets have been transmitted to the bus */ |
| int hpsb_iso_xmit_sync(struct hpsb_iso *iso); |
| |
| /* N packets have been read out of the buffer, re-use the buffer space */ |
| int hpsb_iso_recv_release_packets(struct hpsb_iso *recv, |
| unsigned int n_packets); |
| |
| /* check for arrival of new packets immediately (even if irq_interval |
| * has not yet been reached) */ |
| int hpsb_iso_recv_flush(struct hpsb_iso *iso); |
| |
| /* returns # of packets ready to send or receive */ |
| int hpsb_iso_n_ready(struct hpsb_iso *iso); |
| |
| /* the following are callbacks available to low-level drivers */ |
| |
| /* call after a packet has been transmitted to the bus (interrupt context is OK) |
| * 'cycle' is the _exact_ cycle the packet was sent on |
| * 'error' should be non-zero if some sort of error occurred when sending the |
| * packet */ |
| void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error); |
| |
| /* call after a packet has been received (interrupt context OK) */ |
| void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len, |
| u16 total_len, u16 cycle, u8 channel, u8 tag, |
| u8 sy); |
| |
| /* call to wake waiting processes after buffer space has opened up. */ |
| void hpsb_iso_wake(struct hpsb_iso *iso); |
| |
| #endif /* IEEE1394_ISO_H */ |