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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/ieee1394/dv1394-private.h | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/ieee1394/dv1394-private.h')
-rw-r--r-- | drivers/ieee1394/dv1394-private.h | 587 |
1 files changed, 587 insertions, 0 deletions
diff --git a/drivers/ieee1394/dv1394-private.h b/drivers/ieee1394/dv1394-private.h new file mode 100644 index 0000000..80b5ac7 --- /dev/null +++ b/drivers/ieee1394/dv1394-private.h @@ -0,0 +1,587 @@ +/* + * dv1394-private.h - DV input/output over IEEE 1394 on OHCI chips + * Copyright (C)2001 Daniel Maas <dmaas@dcine.com> + * receive by Dan Dennedy <dan@dennedy.org> + * + * based on: + * video1394.h - driver for OHCI 1394 boards + * Copyright (C)1999,2000 Sebastien Rougeaux <sebastien.rougeaux@anu.edu.au> + * Peter Schlaile <udbz@rz.uni-karlsruhe.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifndef _DV_1394_PRIVATE_H +#define _DV_1394_PRIVATE_H + +#include "ieee1394.h" +#include "ohci1394.h" +#include "dma.h" + +/* data structures private to the dv1394 driver */ +/* none of this is exposed to user-space */ + + +/* + the 8-byte CIP (Common Isochronous Packet) header that precedes + each packet of DV data. + + See the IEC 61883 standard. +*/ + +struct CIP_header { unsigned char b[8]; }; + +static inline void fill_cip_header(struct CIP_header *cip, + unsigned char source_node_id, + unsigned long counter, + enum pal_or_ntsc format, + unsigned long timestamp) +{ + cip->b[0] = source_node_id; + cip->b[1] = 0x78; /* packet size in quadlets (480/4) - even for empty packets! */ + cip->b[2] = 0x00; + cip->b[3] = counter; + + cip->b[4] = 0x80; /* const */ + + switch(format) { + case DV1394_PAL: + cip->b[5] = 0x80; + break; + case DV1394_NTSC: + cip->b[5] = 0x00; + break; + } + + cip->b[6] = timestamp >> 8; + cip->b[7] = timestamp & 0xFF; +} + + + +/* + DMA commands used to program the OHCI's DMA engine + + See the Texas Instruments OHCI 1394 chipset documentation. +*/ + +struct output_more_immediate { u32 q[8]; }; +struct output_more { u32 q[4]; }; +struct output_last { u32 q[4]; }; +struct input_more { u32 q[4]; }; +struct input_last { u32 q[4]; }; + +/* outputs */ + +static inline void fill_output_more_immediate(struct output_more_immediate *omi, + unsigned char tag, + unsigned char channel, + unsigned char sync_tag, + unsigned int payload_size) +{ + omi->q[0] = cpu_to_le32(0x02000000 | 8); /* OUTPUT_MORE_IMMEDIATE; 8 is the size of the IT header */ + omi->q[1] = 0; + omi->q[2] = 0; + omi->q[3] = 0; + + /* IT packet header */ + omi->q[4] = cpu_to_le32( (0x0 << 16) /* IEEE1394_SPEED_100 */ + | (tag << 14) + | (channel << 8) + | (TCODE_ISO_DATA << 4) + | (sync_tag) ); + + /* reserved field; mimic behavior of my Sony DSR-40 */ + omi->q[5] = cpu_to_le32((payload_size << 16) | (0x7F << 8) | 0xA0); + + omi->q[6] = 0; + omi->q[7] = 0; +} + +static inline void fill_output_more(struct output_more *om, + unsigned int data_size, + unsigned long data_phys_addr) +{ + om->q[0] = cpu_to_le32(data_size); + om->q[1] = cpu_to_le32(data_phys_addr); + om->q[2] = 0; + om->q[3] = 0; +} + +static inline void fill_output_last(struct output_last *ol, + int want_timestamp, + int want_interrupt, + unsigned int data_size, + unsigned long data_phys_addr) +{ + u32 temp = 0; + temp |= 1 << 28; /* OUTPUT_LAST */ + + if (want_timestamp) /* controller will update timestamp at DMA time */ + temp |= 1 << 27; + + if (want_interrupt) + temp |= 3 << 20; + + temp |= 3 << 18; /* must take branch */ + temp |= data_size; + + ol->q[0] = cpu_to_le32(temp); + ol->q[1] = cpu_to_le32(data_phys_addr); + ol->q[2] = 0; + ol->q[3] = 0; +} + +/* inputs */ + +static inline void fill_input_more(struct input_more *im, + int want_interrupt, + unsigned int data_size, + unsigned long data_phys_addr) +{ + u32 temp = 2 << 28; /* INPUT_MORE */ + temp |= 8 << 24; /* s = 1, update xferStatus and resCount */ + if (want_interrupt) + temp |= 0 << 20; /* interrupts, i=0 in packet-per-buffer mode */ + temp |= 0x0 << 16; /* disable branch to address for packet-per-buffer mode */ + /* disable wait on sync field, not used in DV :-( */ + temp |= data_size; + + im->q[0] = cpu_to_le32(temp); + im->q[1] = cpu_to_le32(data_phys_addr); + im->q[2] = 0; /* branchAddress and Z not use in packet-per-buffer mode */ + im->q[3] = 0; /* xferStatus & resCount, resCount must be initialize to data_size */ +} + +static inline void fill_input_last(struct input_last *il, + int want_interrupt, + unsigned int data_size, + unsigned long data_phys_addr) +{ + u32 temp = 3 << 28; /* INPUT_LAST */ + temp |= 8 << 24; /* s = 1, update xferStatus and resCount */ + if (want_interrupt) + temp |= 3 << 20; /* enable interrupts */ + temp |= 0xC << 16; /* enable branch to address */ + /* disable wait on sync field, not used in DV :-( */ + temp |= data_size; + + il->q[0] = cpu_to_le32(temp); + il->q[1] = cpu_to_le32(data_phys_addr); + il->q[2] = cpu_to_le32(1); /* branchAddress (filled in later) and Z = 1 descriptor in next block */ + il->q[3] = cpu_to_le32(data_size); /* xferStatus & resCount, resCount must be initialize to data_size */ +} + + + +/* + A "DMA descriptor block" consists of several contiguous DMA commands. + struct DMA_descriptor_block encapsulates all of the commands necessary + to send one packet of DV data. + + There are three different types of these blocks: + + 1) command to send an empty packet (CIP header only, no DV data): + + OUTPUT_MORE-Immediate <-- contains the iso header in-line + OUTPUT_LAST <-- points to the CIP header + + 2) command to send a full packet when the DV data payload does NOT + cross a page boundary: + + OUTPUT_MORE-Immediate <-- contains the iso header in-line + OUTPUT_MORE <-- points to the CIP header + OUTPUT_LAST <-- points to entire DV data payload + + 3) command to send a full packet when the DV payload DOES cross + a page boundary: + + OUTPUT_MORE-Immediate <-- contains the iso header in-line + OUTPUT_MORE <-- points to the CIP header + OUTPUT_MORE <-- points to first part of DV data payload + OUTPUT_LAST <-- points to second part of DV data payload + + This struct describes all three block types using unions. + + !!! It is vital that an even number of these descriptor blocks fit on one + page of memory, since a block cannot cross a page boundary !!! + + */ + +struct DMA_descriptor_block { + + union { + struct { + /* iso header, common to all output block types */ + struct output_more_immediate omi; + + union { + /* empty packet */ + struct { + struct output_last ol; /* CIP header */ + } empty; + + /* full packet */ + struct { + struct output_more om; /* CIP header */ + + union { + /* payload does not cross page boundary */ + struct { + struct output_last ol; /* data payload */ + } nocross; + + /* payload crosses page boundary */ + struct { + struct output_more om; /* data payload */ + struct output_last ol; /* data payload */ + } cross; + } u; + + } full; + } u; + } out; + + struct { + struct input_last il; + } in; + + } u; + + /* ensure that PAGE_SIZE % sizeof(struct DMA_descriptor_block) == 0 + by padding out to 128 bytes */ + u32 __pad__[12]; +}; + + +/* struct frame contains all data associated with one frame in the + ringbuffer these are allocated when the DMA context is initialized + do_dv1394_init(). They are re-used after the card finishes + transmitting the frame. */ + +struct video_card; /* forward declaration */ + +struct frame { + + /* points to the struct video_card that owns this frame */ + struct video_card *video; + + /* index of this frame in video_card->frames[] */ + unsigned int frame_num; + + /* FRAME_CLEAR - DMA program not set up, waiting for data + FRAME_READY - DMA program written, ready to transmit + + Changes to these should be locked against the interrupt + */ + enum { + FRAME_CLEAR = 0, + FRAME_READY + } state; + + /* whether this frame has been DMA'ed already; used only from + the IRQ handler to determine whether the frame can be reset */ + int done; + + + /* kernel virtual pointer to the start of this frame's data in + the user ringbuffer. Use only for CPU access; to get the DMA + bus address you must go through the video->user_dma mapping */ + unsigned long data; + + /* Max # of packets per frame */ +#define MAX_PACKETS 500 + + + /* a PAGE_SIZE memory pool for allocating CIP headers + !header_pool must be aligned to PAGE_SIZE! */ + struct CIP_header *header_pool; + dma_addr_t header_pool_dma; + + + /* a physically contiguous memory pool for allocating DMA + descriptor blocks; usually around 64KB in size + !descriptor_pool must be aligned to PAGE_SIZE! */ + struct DMA_descriptor_block *descriptor_pool; + dma_addr_t descriptor_pool_dma; + unsigned long descriptor_pool_size; + + + /* # of packets allocated for this frame */ + unsigned int n_packets; + + + /* below are several pointers (kernel virtual addresses, not + DMA bus addresses) to parts of the DMA program. These are + set each time the DMA program is written in + frame_prepare(). They are used later on, e.g. from the + interrupt handler, to check the status of the frame */ + + /* points to status/timestamp field of first DMA packet */ + /* (we'll check it later to monitor timestamp accuracy) */ + u32 *frame_begin_timestamp; + + /* the timestamp we assigned to the first packet in the frame */ + u32 assigned_timestamp; + + /* pointer to the first packet's CIP header (where the timestamp goes) */ + struct CIP_header *cip_syt1; + + /* pointer to the second packet's CIP header + (only set if the first packet was empty) */ + struct CIP_header *cip_syt2; + + /* in order to figure out what caused an interrupt, + store pointers to the status fields of the two packets + that can cause interrupts. We'll check these from the + interrupt handler. + */ + u32 *mid_frame_timestamp; + u32 *frame_end_timestamp; + + /* branch address field of final packet. This is effectively + the "tail" in the chain of DMA descriptor blocks. + We will fill it with the address of the first DMA descriptor + block in the subsequent frame, once it is ready. + */ + u32 *frame_end_branch; + + /* the number of descriptors in the first descriptor block + of the frame. Needed to start DMA */ + int first_n_descriptors; +}; + + +struct packet { + u16 timestamp; + u16 invalid; + u16 iso_header; + u16 data_length; + u32 cip_h1; + u32 cip_h2; + unsigned char data[480]; + unsigned char padding[16]; /* force struct size =512 for page alignment */ +}; + + +/* allocate/free a frame */ +static struct frame* frame_new(unsigned int frame_num, struct video_card *video); +static void frame_delete(struct frame *f); + +/* reset f so that it can be used again */ +static void frame_reset(struct frame *f); + +/* struct video_card contains all data associated with one instance + of the dv1394 driver +*/ +enum modes { + MODE_RECEIVE, + MODE_TRANSMIT +}; + +struct video_card { + + /* ohci card to which this instance corresponds */ + struct ti_ohci *ohci; + + /* OHCI card id; the link between the VFS inode and a specific video_card + (essentially the device minor number) */ + int id; + + /* entry in dv1394_cards */ + struct list_head list; + + /* OHCI card IT DMA context number, -1 if not in use */ + int ohci_it_ctx; + struct ohci1394_iso_tasklet it_tasklet; + + /* register offsets for current IT DMA context, 0 if not in use */ + u32 ohci_IsoXmitContextControlSet; + u32 ohci_IsoXmitContextControlClear; + u32 ohci_IsoXmitCommandPtr; + + /* OHCI card IR DMA context number, -1 if not in use */ + struct ohci1394_iso_tasklet ir_tasklet; + int ohci_ir_ctx; + + /* register offsets for current IR DMA context, 0 if not in use */ + u32 ohci_IsoRcvContextControlSet; + u32 ohci_IsoRcvContextControlClear; + u32 ohci_IsoRcvCommandPtr; + u32 ohci_IsoRcvContextMatch; + + + /* CONCURRENCY CONTROL */ + + /* there are THREE levels of locking associated with video_card. */ + + /* + 1) the 'open' flag - this prevents more than one process from + opening the device. (the driver currently assumes only one opener). + This is a regular int, but use test_and_set_bit() (on bit zero) + for atomicity. + */ + unsigned long open; + + /* + 2) the spinlock - this provides mutual exclusion between the interrupt + handler and process-context operations. Generally you must take the + spinlock under the following conditions: + 1) DMA (and hence the interrupt handler) may be running + AND + 2) you need to operate on the video_card, especially active_frame + + It is OK to play with video_card without taking the spinlock if + you are certain that DMA is not running. Even if DMA is running, + it is OK to *read* active_frame with the lock, then drop it + immediately. This is safe because the interrupt handler will never + advance active_frame onto a frame that is not READY (and the spinlock + must be held while marking a frame READY). + + spinlock is also used to protect ohci_it_ctx and ohci_ir_ctx, + which can be accessed from both process and interrupt context + */ + spinlock_t spinlock; + + /* flag to prevent spurious interrupts (which OHCI seems to + generate a lot :) from accessing the struct */ + int dma_running; + + /* + 3) the sleeping semaphore 'sem' - this is used from process context only, + to serialize various operations on the video_card. Even though only one + open() is allowed, we still need to prevent multiple threads of execution + from entering calls like read, write, ioctl, etc. + + I honestly can't think of a good reason to use dv1394 from several threads + at once, but we need to serialize anyway to prevent oopses =). + + NOTE: if you need both spinlock and sem, take sem first to avoid deadlock! + */ + struct semaphore sem; + + /* people waiting for buffer space, please form a line here... */ + wait_queue_head_t waitq; + + /* support asynchronous I/O signals (SIGIO) */ + struct fasync_struct *fasync; + + /* the large, non-contiguous (rvmalloc()) ringbuffer for DV + data, exposed to user-space via mmap() */ + unsigned long dv_buf_size; + struct dma_region dv_buf; + + /* next byte in the ringbuffer that a write() call will fill */ + size_t write_off; + + struct frame *frames[DV1394_MAX_FRAMES]; + + /* n_frames also serves as an indicator that this struct video_card is + initialized and ready to run DMA buffers */ + + int n_frames; + + /* this is the frame that is currently "owned" by the OHCI DMA controller + (set to -1 iff DMA is not running) + + ! must lock against the interrupt handler when accessing it ! + + RULES: + + Only the interrupt handler may change active_frame if DMA + is running; if not, process may change it + + If the next frame is READY, the interrupt handler will advance + active_frame when the current frame is finished. + + If the next frame is CLEAR, the interrupt handler will re-transmit + the current frame, and the dropped_frames counter will be incremented. + + The interrupt handler will NEVER advance active_frame to a + frame that is not READY. + */ + int active_frame; + int first_run; + + /* the same locking rules apply to these three fields also: */ + + /* altered ONLY from process context. Must check first_clear_frame->state; + if it's READY, that means the ringbuffer is full with READY frames; + if it's CLEAR, that means one or more ringbuffer frames are CLEAR */ + unsigned int first_clear_frame; + + /* altered both by process and interrupt */ + unsigned int n_clear_frames; + + /* only altered by the interrupt */ + unsigned int dropped_frames; + + + + /* the CIP accumulator and continuity counter are properties + of the DMA stream as a whole (not a single frame), so they + are stored here in the video_card */ + + unsigned long cip_accum; + unsigned long cip_n, cip_d; + unsigned int syt_offset; + unsigned int continuity_counter; + + enum pal_or_ntsc pal_or_ntsc; + + /* redundant, but simplifies the code somewhat */ + unsigned int frame_size; /* in bytes */ + + /* the isochronous channel to use, -1 if video card is inactive */ + int channel; + + + /* physically contiguous packet ringbuffer for receive */ + struct dma_region packet_buf; + unsigned long packet_buf_size; + + unsigned int current_packet; + int first_frame; /* received first start frame marker? */ + enum modes mode; +}; + +/* + if the video_card is not initialized, then the ONLY fields that are valid are: + ohci + open + n_frames +*/ + +static inline int video_card_initialized(struct video_card *v) +{ + return v->n_frames > 0; +} + +static int do_dv1394_init(struct video_card *video, struct dv1394_init *init); +static int do_dv1394_init_default(struct video_card *video); +static void do_dv1394_shutdown(struct video_card *video, int free_user_buf); + + +/* NTSC empty packet rate accurate to within 0.01%, + calibrated against a Sony DSR-40 DVCAM deck */ + +#define CIP_N_NTSC 68000000 +#define CIP_D_NTSC 1068000000 + +#define CIP_N_PAL 1 +#define CIP_D_PAL 16 + +#endif /* _DV_1394_PRIVATE_H */ + |