Show page

Differences

This shows you the differences between two versions of the page.

--- ass:labs-2025:01:tasks:02 [2025/08/03 16:59]
florin.stancu created
+++ ass:labs-2025:01:tasks:02 [2025/08/04 19:51] (current)
florin.stancu
@@ Line 1: / Line 1: @@
 ==== 02. Creating the Firmware Image Package ====
-This package will contain **BL2** (U-Boot SPL), **BL31** (ATF-A) and **BL33** (fully-featured U-Boot) and some proprietary firmware (//yikes!//). The Secure OS (**BL32**) is outside the scope of this lab; even if we did bother to include it, it would just //be there//, doing nothing.
+This package will contain **BL2** (U-Boot SPL), **BL31** (ARM Trusted Firmware) and **BL33** (normal/full U-Boot) and some proprietary firmware (//yikes!//). The Secure OS (**BL32**) is outside the scope of this lab; even if we did bother to include it, it would just //be there//, doing nothing.
 Following this exercise, we should be able to reach the first step of the booting sequence that //can// be interactive; meaning that we'll be able to interact with a shell implemented in U-Boot!
@@ Line 24: / Line 24: @@
 == Step 2.1. Build ARM Trusted Firmware-A (ATF / TF-A) ==
-Following a successful build process, you should obtain a **bl31.bin** file (take note if its location, for you will need it later).
 <note tip>
@@ Line 38: / Line 36: @@
 If you're still having problems, you can also read the [[https://docs.u-boot.org/en/latest/board/nxp/imx93_frdm.html|u-boot mainline steps for FRDM iMX93]].
+Following a successful build process, you should obtain a **bl31.bin** file (take note if its location (use ''find'' to find it if lost) and copy it to your ''artifacts/'' dir, for you will need it later).
 === The iMX proprietary firmware ===
@@ Line 59: / Line 59: @@
 (oh, and since we're on Linux, don't forget to apply to executable bit -- ''chmod +x <filename>'').
-What we're actually interested in are the following files (find them and put them inside your own ''firmware-files''' directory, we'll make use of them later):
+What we're actually interested in are the following files (find them and put them inside your own ''artifacts'' directory, we'll make use of them later):
 <code bash>
-# from the firmware-imx:
+# from the firmware-imx (8 files!):
-lpddr4_imem_1d_v202201.bin lpddr4_dmem_1d_v202201.bin
+lpddr4_imem_1d_v202201.bin     lpddr4_dmem_1d_v202201.bin
-lpddr4_imem_2d_v202201.bin lpddr4_dmem_2d_v202201.bin
+lpddr4_imem_2d_v202201.bin     lpddr4_dmem_2d_v202201.bin
-lpddr4_pmu_train_1d_dmem.binlpddr4_pmu_train_1d_imem.bin
+lpddr4_pmu_train_1d_dmem.bin   lpddr4_pmu_train_1d_imem.bin
-lpddr4_pmu_train_2d_dmem.bin lpddr4_pmu_train_2d_imem.bin
+lpddr4_pmu_train_2d_dmem.bin   lpddr4_pmu_train_2d_imem.bin
-# and this is from firmware-sentinel:
+# and this is from firmware-sentinel (just 1 req., fortunately):
 mx93a1-ahab-container.img
 </code>
@@ Line 147: / Line 147: @@
   * ''arch/arm/dts/imx93-11x11-frdm.dtb'': a Device Tree Blob (DTB) which we'll also require -- see below.
-Copy them all inside your //special// ''firmware-files'' directory (which you created earlier, right?).
+Copy them all inside your //special// ''artifacts'' directory (which you created earlier, right?).
 <note>
@@ Line 164: / Line 164: @@
 </note>
-=== Step 2.4. Generate the firmware package ===
+=== The Firmware Image Package ===
 Now that we have all necessary binaries either downloaded or compiled ourselves, all that is left is to combine them in a manner that can be understood by the processor's first boot stage (**BL1** -- inside ROM memory).
+The format is specific to each model and is usually described inside the chip's [[https://www.nxp.com/webapp/Download?colCode=IMX93RM|Technical Reference Manual]] (note: requires sign in!).
+{{ :ass:labs-2025:01:imx93_firm_image_format.png?600 |}}
+In order to generate a binary image file in this format, we must use a specific tool ofc.
 Since 2022, U-Boot's tool of choice for this task is [[https://u-boot.readthedocs.io/en/latest/develop/package/binman.html|binman]]. This tool uses a platform-specific config file that specifies what components should be included and where they should be placed in memory. For our platform (i.e.: i.MX93) this file would be ''arch/arm/dts/imx93-11x11-frdm-u-boot.dtsi''.
@@ Line 172: / Line 179: @@
 **However**, since the U-Boot version that we are using is older and the board manufacturer did not add proper support for binman, **we are going to use the older method**, based on [[https://linux.die.net/man/1/mkimage|mkimage]] (part of the U-Boot repo or as a package on most distros). In order to spare ourselves some pain, we are going to use NXP's [[https://github.com/nxp-imx/imx-mkimage/|imx-mkimage]] implementation which knows the proper offsets where the images should be loaded... but beware: it's not very pretty to use!
-So clone the ''imx-mkimage'' folder and navigate to it!
+=== Step 2.6. Generate flash.bin (the FIP) ===
-In their source tree you will find a number of subdirectories corresponding to different versions of the i.MX platform. Select the one which corresponds to our board.
+Clone the ''imx-mkimage'' project from git and ''cd'' to it!
+In their source tree you will find a number of subdirectories corresponding to different versions of the i.MX platform. Select the one which corresponds to our board:
+<code>
+imx-mkimage
+├── iMX8DXL
+├── iMX8M
+├── iMX8QM
+├── iMX8QX
+├── iMX8ULP
+├── iMX91
+├── iMX93
+├── iMX94
+├── iMX95
+├── scripts
+└── src
+</code>
-When you get there (that is, inside the ''iMX93'' subdirectory), you will have to copy all the ''firmware-files'' you compiled so far + the ones downloaded/extracted from proprietary firmware archive (trust us here: **make a script to do all this automatically**! you'll need to do it tens -- probably hundreds -- of times!).
+When you get there (that is, inside the ''iMX93'' subdirectory), you will have to copy all the ''artifacts'' (remember we had you manage them all inside a new folder?) you compiled so far + the ones downloaded/extracted from proprietary firmware archive (trust us here: **make a script/Makefile goal to do all this automatically**! you'll need to do it tens -- probably hundreds -- of times!).
 In addition to these, you will have to copy the base **mkimage** tool generated in the U-Boot directory, see if you can ''find'' it '';)'' you must rename it as **mkimage_uboot** inside the ''iMX93'' subdirectory.
-Once you have all these (see below), run make **in the parent directory** (check and see where it has that Makefile!) with the ''flash_singleboot'' target, while specifying the platform in the ''SOC=iMX93'' argument (note that cASE!), and the name of the DTB copied over from U-Boot in the ''dtbs='' argument. The output firmware image should be called **flash.bin**. Here's the final contents of the directory:
+Once you have all these (see below), run ''make'' **in the parent directory of imx-mkimage** (check and see where it has that Makefile!) with the ''flash_singleboot'' target, while specifying the platform in the ''SOC=iMX93'' argument (note that cASE!), and the name of the DTB copied over from U-Boot in the ''dtbs='' argument. The output firmware image should be called **flash.bin**. Here's the final contents of the directory:
 <code>
 imx-mkimage/iMX93
-├── bl31.bin                       # generated, we don't care
+├── bl31.bin                       # ARM Trusted Firmware
 ├── boot-spl-container.img         # also generated
 ├── flash.bin                      # generated by `make SOC=... dtbs=...`