On 2018-06-25 23:21, Rob Herring wrote:
On Tue, Jun 12, 2018 at 12:44:33PM +0200, Rafał Miłecki wrote:
From: Rafał Miłecki <rafal@xxxxxxxxxx>
Broadcom based home router devices use TRX firmware format. It's a
container that can hold few partitions. If operating system is
expected
to access them it has to understand that format and parse flash data
accordingly.
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
.../bindings/mtd/partitions/brcm,trx.txt | 35
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create mode 100644
Documentation/devicetree/bindings/mtd/partitions/brcm,trx.txt
diff --git
a/Documentation/devicetree/bindings/mtd/partitions/brcm,trx.txt
b/Documentation/devicetree/bindings/mtd/partitions/brcm,trx.txt
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index 000000000000..e590b884e5ac
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@@ -0,0 +1,35 @@
+Broadcom TRX Container Partition
+================================
+
+TRX is Broadcom's official firmware format for the BCM947xx boards.
It's used by
+most of the vendors building devices based on Broadcom's BCM47xx SoCs
and is
+supported by the CFE bootloader.
+
+Design of the TRX format is very minimalistic. Its header contains
+identification fields, CRC32 checksum and the locations of embedded
partitions.
+Its purpose is to store a few partitions in a format that can be
distributed as
+a standalone file and written in a flash memory.
+
+Container can hold up to 4 partitions. The first partition has to
contain a
+device executable binary (e.g. a kernel) as it's what the CFE
bootloader starts
+executing. Other partitions can be used for operating system
purposes. This is
+useful for systems that keep kernel and rootfs separated.
+
+TRX doesn't enforce any strict partition boundaries or size limits.
All
+partitions have to be less than the 4GiB max size limit.
+
+There are two existing/known TRX variants:
+1) v1 which contains 3 partitions
+2) v2 which contains 4 partitions
+
+Required properties:
+- compatible : (required) must be either: "brcm,trx-v1" or
"brcm,trx-v2"
+ followed by "brcm,trx"
What is the purpose of brcm,trx? Either that alone is enough or you
need
v1/v2 to distinguish the difference. You shouldn't need both.
I guess I incorrectly tried some pattern I saw when specifying SoC
compatibility.
Can I have you advise here, please?
No TRX supporting code really needs a hint about used TRX version. TRX
format (header) contains "version" field so any code dealing with TRX
format can check that field. Then it knows what version it's dealing
with.
Which binding(s) should I use in that case?
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