From 392ae40c2c10e0bf657723bc3fdd8a9a7fa54b77 Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Fri, 7 Dec 2018 00:13:22 -0800 Subject: Documentation: i.MX: Document how to use GPT Document a way to avoid clashes between i.MX boot info/Barebox and GPT's Partition Entry Array. Signed-off-by: Andrey Smirnov Signed-off-by: Sascha Hauer --- Documentation/boards/imx.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/boards/imx.rst b/Documentation/boards/imx.rst index 99ca10b7cc..35a180b0dd 100644 --- a/Documentation/boards/imx.rst +++ b/Documentation/boards/imx.rst @@ -60,6 +60,25 @@ The images can also always be started second stage:: bootm /mnt/tftp/barebox-freescale-imx51-babbage.img +Using GPT on i.MX +^^^^^^^^^^^^^^^^^ + +For i.MX SoCs that place vendor specific header at +1KiB mark of a +boot medium, special care needs to be taken when parition that medium +with GPT. In order to make room for i.MX boot header GPT Partition +Entry Array needs to be moved from its typical location, LBA 2, to an +offset past vendor specific information. One way to do this would be +to use ``-j`` or ``--adjust-main-table`` option of ``sgdisk``. For +example, the following sequence: + + sgdisk -Z + sgdisk -o -j 2048 -n 1:8192:+100M + +will create a single GPT partition starting at LBA 8192 and would +place Partition Entry Array starting at LBA 2048 which should leave +enough room for Barebox/i.MX boot header. Once that is done ``dd`` +command above can be used to place Barebox on the same medium. + Information about the ``imx-image`` tool ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -- cgit v1.2.3