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TWiki > Main > IngenicJz47xx

Ingenic Jz47xx Series

Information
Jz4720
Jz4730
- Jz4732
Jz4740
Source code
Other links

Information

Ingenic seems to have released a lot of information regarding their chipsets including (GPL'ed) source code. Although, not everything is publicly on their FTP server; what's missing exactly are the datasheets, MXU instruction datasheet, ...
All the boards in the Jz47xx series consist of a XBurst processor, which is a MIPS processor clocked at 240->400Mhz.

Jz4720

Jz4720 is a low cost multimedia application processor targeting for mobile devices like MP4 players, electronic dictionaries, ...

Jz4730

Jz4730 is a multimedia application processor incorporating XBurst technology targeted at mobile and general embedded devices.
The CPU core is based on leading micro-architecture technology; this processor provides high integration, high performance and a low power consumption solution for embedded devices.

Jz4732

This chipset is undocumented, but believed to be a modified Jz4740. Probably one main difference will be the lack of TV-out.

The processor itself is identified as 0x0AD0024F (which is the same as the Jz4740).

The Jz4732 is a popular choice for some Chinese MP4 players:

Jz4740

Jz4740 is a multimedia application processor targeted at mobile devices like smart-phone, PMP and GPS.
Incorporates the XBurst CPU core based on leading micro-architecture technology, this processor provides high integration, high performance and a low power consumption solution for embedded devices.

Players using this chipset:

Onda VX767

Hardware information

CPU info

C0_CONFIG1 has this value: 0x3E63318A
Analyses:

EJTAG present
watch registers present
Dcache associativity = 3
Dcache line size = 4
Dcache sets per way = 1
Icache associativity = 4
Icache line size = 4
Icache sets per way = 1
Number of MMU entries = 32

Memory layout

VA: 0x080000000 -> 0x080004000 = 16KB I-Cache
VA: 0x080000080 = IRQ handler/ISR
VA: 0x080000200 = IRQ handler/ISR when IV is set in C0_CAUSE
VA: 0x0BXXXXXXX = hardware memory registers
PA: 0x1FC00000 -> 0x1FC01000 = On-chip Boot ROM

Boot up

The Jz4740 can be set to boot from NOR or NAND.
If booted from NAND, the CPU fetches the first page from NAND and uses the first 4 bytes on it to know how the NAND chip should be treated (16/8-bit bus, 2/3 row cycles).
After that it copies the first 8kB from NAND and copies it to the I-Cache for execution.

Ingenic Media Extension Instruction Set

According to the MXU User Guide, the XBurst processor supports additional instructions called the Ingenic Media Extension Instruction Set (they call it an SIMD instruction set).

Excerpt from the PDF:
Processors (such as the Jz4740) have 60 extra SIMD commands used for the optimization of multimedia codecs such as MPEG4, H264, VC-1, RMVB, ... and other multimedia decoder algorithms that can be optimized using the MXU.

Image Processing Unit

The Jz4740 also has an IPU which has the following features:

Video frame resize
Color space conversion: 420/444/422 YUV to RGB convert

Source code

Ingenic provides a lot of (GPL) source code for their boards.
As their FTP server is rather slow, I mirrored some files: