1*4882a593SmuzhiyunBroadcom TRX Container Partition 2*4882a593Smuzhiyun================================ 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunTRX is Broadcom's official firmware format for the BCM947xx boards. It's used by 5*4882a593Smuzhiyunmost of the vendors building devices based on Broadcom's BCM47xx SoCs and is 6*4882a593Smuzhiyunsupported by the CFE bootloader. 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunDesign of the TRX format is very minimalistic. Its header contains 9*4882a593Smuzhiyunidentification fields, CRC32 checksum and the locations of embedded partitions. 10*4882a593SmuzhiyunIts purpose is to store a few partitions in a format that can be distributed as 11*4882a593Smuzhiyuna standalone file and written in a flash memory. 12*4882a593Smuzhiyun 13*4882a593SmuzhiyunContainer can hold up to 4 partitions. The first partition has to contain a 14*4882a593Smuzhiyundevice executable binary (e.g. a kernel) as it's what the CFE bootloader starts 15*4882a593Smuzhiyunexecuting. Other partitions can be used for operating system purposes. This is 16*4882a593Smuzhiyunuseful for systems that keep kernel and rootfs separated. 17*4882a593Smuzhiyun 18*4882a593SmuzhiyunTRX doesn't enforce any strict partition boundaries or size limits. All 19*4882a593Smuzhiyunpartitions have to be less than the 4GiB max size limit. 20*4882a593Smuzhiyun 21*4882a593SmuzhiyunThere are two existing/known TRX variants: 22*4882a593Smuzhiyun1) v1 which contains 3 partitions 23*4882a593Smuzhiyun2) v2 which contains 4 partitions 24*4882a593Smuzhiyun 25*4882a593SmuzhiyunThere aren't separated compatible bindings for them as version can be trivialy 26*4882a593Smuzhiyundetected by a software parsing TRX header. 27*4882a593Smuzhiyun 28*4882a593SmuzhiyunRequired properties: 29*4882a593Smuzhiyun- compatible : (required) must be "brcm,trx" 30*4882a593Smuzhiyun 31*4882a593SmuzhiyunExample: 32*4882a593Smuzhiyun 33*4882a593Smuzhiyunflash@0 { 34*4882a593Smuzhiyun partitions { 35*4882a593Smuzhiyun compatible = "brcm,trx"; 36*4882a593Smuzhiyun }; 37*4882a593Smuzhiyun}; 38