| /* | |
| * 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 <linux/spinlock_types.h> | |
| #include <asm/atomic.h> | |
| #include <asm/types.h> | |
| #include "dma.h" | |
| struct hpsb_host; | |
| /* 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 */ |