43 lines
1.4 KiB
Plaintext
43 lines
1.4 KiB
Plaintext
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Broadcom TRX Container Partition
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================================
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TRX is Broadcom's official firmware format for the BCM947xx boards. It's used by
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most of the vendors building devices based on Broadcom's BCM47xx SoCs and is
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supported by the CFE bootloader.
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Design of the TRX format is very minimalistic. Its header contains
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identification fields, CRC32 checksum and the locations of embedded partitions.
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Its purpose is to store a few partitions in a format that can be distributed as
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a standalone file and written in a flash memory.
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Container can hold up to 4 partitions. The first partition has to contain a
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device executable binary (e.g. a kernel) as it's what the CFE bootloader starts
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executing. Other partitions can be used for operating system purposes. This is
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useful for systems that keep kernel and rootfs separated.
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TRX doesn't enforce any strict partition boundaries or size limits. All
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partitions have to be less than the 4GiB max size limit.
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There are two existing/known TRX variants:
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1) v1 which contains 3 partitions
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2) v2 which contains 4 partitions
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There aren't separated compatible bindings for them as version can be trivialy
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detected by a software parsing TRX header.
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Required properties:
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- compatible : (required) must be "brcm,trx"
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Optional properties:
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- brcm,trx-magic: TRX magic, if it is different from the default magic
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0x30524448 as a u32.
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Example:
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flash@0 {
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partitions {
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compatible = "brcm,trx";
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};
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};
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