mirror of
https://github.com/torvalds/linux.git
synced 2024-12-27 05:11:48 +00:00
a63ad325c3
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
140 lines
4.6 KiB
Plaintext
140 lines
4.6 KiB
Plaintext
This document describes the cx2341x memory map and documents some of the register
|
|
space.
|
|
|
|
Note: the memory long words are little-endian ('intel format').
|
|
|
|
Warning! This information was figured out from searching through the memory and
|
|
registers, this information may not be correct and is certainly not complete, and
|
|
was not derived from anything more than searching through the memory space with
|
|
commands like:
|
|
|
|
ivtvctl -O min=0x02000000,max=0x020000ff
|
|
|
|
So take this as is, I'm always searching for more stuff, it's a large
|
|
register space :-).
|
|
|
|
Memory Map
|
|
==========
|
|
|
|
The cx2341x exposes its entire 64M memory space to the PCI host via the PCI BAR0
|
|
(Base Address Register 0). The addresses here are offsets relative to the
|
|
address held in BAR0.
|
|
|
|
0x00000000-0x00ffffff Encoder memory space
|
|
0x00000000-0x0003ffff Encode.rom
|
|
???-??? MPEG buffer(s)
|
|
???-??? Raw video capture buffer(s)
|
|
???-??? Raw audio capture buffer(s)
|
|
???-??? Display buffers (6 or 9)
|
|
|
|
0x01000000-0x01ffffff Decoder memory space
|
|
0x01000000-0x0103ffff Decode.rom
|
|
???-??? MPEG buffers(s)
|
|
0x0114b000-0x0115afff Audio.rom (deprecated?)
|
|
|
|
0x02000000-0x0200ffff Register Space
|
|
|
|
Registers
|
|
=========
|
|
|
|
The registers occupy the 64k space starting at the 0x02000000 offset from BAR0.
|
|
All of these registers are 32 bits wide.
|
|
|
|
DMA Registers 0x000-0xff:
|
|
|
|
0x00 - Control:
|
|
0=reset/cancel, 1=read, 2=write, 4=stop
|
|
0x04 - DMA status:
|
|
1=read busy, 2=write busy, 4=read error, 8=write error, 16=link list error
|
|
0x08 - pci DMA pointer for read link list
|
|
0x0c - pci DMA pointer for write link list
|
|
0x10 - read/write DMA enable:
|
|
1=read enable, 2=write enable
|
|
0x14 - always 0xffffffff, if set any lower instability occurs, 0x00 crashes
|
|
0x18 - ??
|
|
0x1c - always 0x20 or 32, smaller values slow down DMA transactions
|
|
0x20 - always value of 0x780a010a
|
|
0x24-0x3c - usually just random values???
|
|
0x40 - Interrupt status
|
|
0x44 - Write a bit here and shows up in Interrupt status 0x40
|
|
0x48 - Interrupt Mask
|
|
0x4C - always value of 0xfffdffff,
|
|
if changed to 0xffffffff DMA write interrupts break.
|
|
0x50 - always 0xffffffff
|
|
0x54 - always 0xffffffff (0x4c, 0x50, 0x54 seem like interrupt masks, are
|
|
3 processors on chip, Java ones, VPU, SPU, APU, maybe these are the
|
|
interrupt masks???).
|
|
0x60-0x7C - random values
|
|
0x80 - first write linked list reg, for Encoder Memory addr
|
|
0x84 - first write linked list reg, for pci memory addr
|
|
0x88 - first write linked list reg, for length of buffer in memory addr
|
|
(|0x80000000 or this for last link)
|
|
0x8c-0xdc - rest of write linked list reg, 8 sets of 3 total, DMA goes here
|
|
from linked list addr in reg 0x0c, firmware must push through or
|
|
something.
|
|
0xe0 - first (and only) read linked list reg, for pci memory addr
|
|
0xe4 - first (and only) read linked list reg, for Decoder memory addr
|
|
0xe8 - first (and only) read linked list reg, for length of buffer
|
|
0xec-0xff - Nothing seems to be in these registers, 0xec-f4 are 0x00000000.
|
|
|
|
Memory locations for Encoder Buffers 0x700-0x7ff:
|
|
|
|
These registers show offsets of memory locations pertaining to each
|
|
buffer area used for encoding, have to shift them by <<1 first.
|
|
|
|
0x07F8: Encoder SDRAM refresh
|
|
0x07FC: Encoder SDRAM pre-charge
|
|
|
|
Memory locations for Decoder Buffers 0x800-0x8ff:
|
|
|
|
These registers show offsets of memory locations pertaining to each
|
|
buffer area used for decoding, have to shift them by <<1 first.
|
|
|
|
0x08F8: Decoder SDRAM refresh
|
|
0x08FC: Decoder SDRAM pre-charge
|
|
|
|
Other memory locations:
|
|
|
|
0x2800: Video Display Module control
|
|
0x2D00: AO (audio output?) control
|
|
0x2D24: Bytes Flushed
|
|
0x7000: LSB I2C write clock bit (inverted)
|
|
0x7004: LSB I2C write data bit (inverted)
|
|
0x7008: LSB I2C read clock bit
|
|
0x700c: LSB I2C read data bit
|
|
0x9008: GPIO get input state
|
|
0x900c: GPIO set output state
|
|
0x9020: GPIO direction (Bit7 (GPIO 0..7) - 0:input, 1:output)
|
|
0x9050: SPU control
|
|
0x9054: Reset HW blocks
|
|
0x9058: VPU control
|
|
0xA018: Bit6: interrupt pending?
|
|
0xA064: APU command
|
|
|
|
|
|
Interrupt Status Register
|
|
=========================
|
|
|
|
The definition of the bits in the interrupt status register 0x0040, and the
|
|
interrupt mask 0x0048. If a bit is cleared in the mask, then we want our ISR to
|
|
execute.
|
|
|
|
Bit
|
|
31 Encoder Start Capture
|
|
30 Encoder EOS
|
|
29 Encoder VBI capture
|
|
28 Encoder Video Input Module reset event
|
|
27 Encoder DMA complete
|
|
24 Decoder audio mode change detection event (through event notification)
|
|
22 Decoder data request
|
|
20 Decoder DMA complete
|
|
19 Decoder VBI re-insertion
|
|
18 Decoder DMA err (linked-list bad)
|
|
|
|
Missing
|
|
Encoder API call completed
|
|
Decoder API call completed
|
|
Encoder API post(?)
|
|
Decoder API post(?)
|
|
Decoder VTRACE event
|