Ingenic Jz47xx Series
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 is a low cost multimedia application processor targeting for mobile devices like MP4 players, electronic dictionaries, ...
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.
This chipset is undocumented, but believed to be a modified Jz4740.
Ingenic seems to say that it is a Jz4740 meant for exportation outside China.
The processor itself is identified as 0x0AD0024F (which is the same as the Jz4740).
Refer to the Jz4740 for more information.
The Jz4732/Jz4740 is a popular choice among some Chinese MP4 players
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.
C0_CONFIG1 has this value: 0x3E63318A
- 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
- VA: 0x080000000 -> 0x080004000 = 16KB I-Cache
- VA: 0x080000080 = IRQ handler/ISR
- VA: 0x080000200 = IRQ handler/ISR when IV is set in C0_CAUSE
- VA: 0xBXXXXXXX | PA: 0x1XXXXXXX = hardware memory registers
- VA: 0xBFC00000 -> 0xBFC01000 | PA: 0x1FC00000 -> 0x1FC01000 = On-chip Boot ROM
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
Ingenic provides a lot of (GPL) source code for their boards.
As their FTP server
is rather slow, I mirrored some files:
Copyright © by the contributing authors.