The document to descript change the u-boot environment variables under the Linux rootfs.  Also provide a demo on i.MX6ull evk of sdcard mirror.  Linux fw_printenv fw_setenv to access U-Boot's environment variables.pdf  --- the document fw_printenv_fw_setenv_demo_iMX6ullevk_L4.14.98_2.0.0_ga.sdcard  --- demo sdcard mirror

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-342877 

[中文翻译版] 见附件   原文链接： i.MX Create Android SDCard Mirror 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343079 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343046 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343344 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343372 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343273 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343518 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343576 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343761 

Instrumenting A Board To instrument a board, the connection between the power supply and the target device needs to be broken, usually via a series resistor that's placed on the board. Sometimes the inductor needs to be lifted if no series resistor was included on the rail by the board's designer. In the ideal case, through-hole connections were also provided on the board for the connection of these off-board sensors. Here are three close-up photos that show several boards that have been instrumented: In all three cases, the sensors stand in place via the two outer current carrying wires. The middle and right used insulated wires where as the one on the left used bare wires. In all three cases, the sensor's + connection needs to go towards the power supply and the - connection goes to the target device. The outer wires here are 24-26 gauge. (The relatively heavy gauge wire is used to keep the series resistance of inserting a smart sensor to a minimum.) The ground connection is the middle hole of the smart sensor. In the left and middle photos, a 30 gauge wire connects to the middle hole ground connection on the  board. In the right photo, the ground wire was more conveniently added to a big cap just below the bottom of edge of the photo. Here are wider angle view photos of two of the boards above: The sensors on the left are free-standing since the current carrying wires are stiff enough to hold them upright. Care must be taken since too much flexing will cause a wire to break. Too much bending can also cause a short to the board (and that's why insulated wires were used on these boards). The board on the right has the sensors laying parallel to the board. They are not affixed to the board, but a wire is wrapped around the bundle of ribbon cables out of view past the right edge of the photo. For boards without the through hole connections, the smart sensors need to be immobilized to keep from pulling the SMT pads off the board. If there is room on the board or sides of connectors or large components, the sensors may be attached down with foam double-sticky tape (see photo below, sensor affixed on top i.MX7ULP): For boards where there are no convenient unpopulated areas or there are too many sensors, some other means needs to be devised to immoblize the smart sensors. In the left photo below, two inductors per sensor have been flipped and the two sensors inserted to instrument the two rails. The solder pads on the inductors would easily be broken off by any movement of the smart sensors, so a cage with clamps to hold the ribbon cables was 3D printed. On the back side, there is room for the aggregator to be zip tied to the bottom plate, so the instrumented board can be moved as a single unit with minimal flexing of the ribbon cables.

When you do long test (days or weeks) test on i.MX board and your test fails, you often wants to know what has happen with a JTAG probe. The problem is when you have 50 boards running in parallel, you don't have the budget to have 50 JTAG debug probe. If you do a "hot plug" of your JTAG probe, you have roughly one chance out 2 to reset your board... so you'll have to wait another couple of hour to resee the problem. Anyway to have a reliable JTAG plug with no reset, it is really simple... cut the RESET line on your cable! then you'll still be able to "attach" to your i.MX. On the MEK board, with a 10-pin JTAG connector, you have the cut the cable line 10 of the ribbon cable: On the cable, cut the reset line like this: With my Lauterbach JTAG  probe, when I do a "hot plug" I never have a reset of my i.MX. BR Vincent

The following document contains a list of document, questions and discussions that are relevant in the community based on amount of views. If you are having a problem, doubt or getting started in i.MX processors, you should check the following links to see if your doubt is in there. Yocto Project Freescale Yocto Project main page‌ Yocto Training - HOME‌ i.MX Yocto Project: Frequently Asked Questions‌ Useful bitbake commands‌ Yocto Project Package Management - smart  How to add a new layer and a new recipe in Yocto  Setting up the Eclipse IDE for Yocto Application Development Guide to the .sdcard format  Yocto NFS & TFTP boot  YOCTO project clean  Yocto with a package manager (ex: apt-get)  Yocto Setting the Default Ethernet address and disable DHCP on boot.  i.MX x Building QT for i.MX6  i.MX6/7 DDR Stress Test Tool V3.00  i.MX6DQSDL DDR3 Script Aid  Installing Ubuntu Rootfs on NXP i.MX6 boards  iMX6DQ MAX9286 MIPI CSI2 720P camera surround view solution for Linux BSP i.MX Design&Tool Lists  Simple GPIO Example - quandry  i.MX6 GStreamer-imx Plugins - Tutorial & Example Pipelines  Streaming USB Webcam over Network  Step-by-step: How to setup TI Wilink (WL18xx) with iMX6 Linux 3.10.53  Linux / Kernel Copying Files Between Windows and Linux using PuTTY  Building Linux Kernel  Patch to support uboot logo keep from uboot to kernel for NXP Linux and Android BSP (HDMI, LCD and LVDS)  load kernel from SD card in U-boot  Changing the Kernel configuration for i.MX6 SABRE  Android  The Android Booting process  What is inside the init.rc and what is it used for.  Others How to use qtmultimedia(QML) with Gstreamer 1.0

Host Environment: ubuntu 16.04 LTS Linux BSP For i.MX : version 4.9.88 The document has 5 main contents: 1. Compiling core-image-base in Yocto BSP --Copy u-boot source code to a new directory --Copy linux kernel source code to a new directory 2. Exporting 4.9.88 toolchain from Freescale Yocto BSP (1) Using MACHINE=imx7dsabresd to export the toolchain (2) Using MACHINE=imx6qsabresd to export the toolchain. Actually above 2 are the same toolchain after exporting. Here , only show any one of boards(not ARM64) can be used for MACHINE. So users only need to export it for one time, select (1) or (2) to export toolchain. (3) Using MACHINE=imx8mqevk to export ARM64 toolchain 3. Compling u-boot & linux kernel under Stanalone iMX7DSabreSD --Compiling  u-boot for imx7dsabresd --Compiling kernel and dtb for imx7dsabresd iMX8MQEVK --Compiling u-boot for imx8mqevk --Compiling kernel and dtb for imx8mqevk 4. Compiling OS Firmware for i.MX7DSabreSD board --u-boot for mfg tools --kernel and dtb for mfg tools 5. Copy OS Firmware to the related path of MFG tools --------------------------------------------------------------------------------------------------------------------------- [Content of Document] 1. Compiling core-image-base in Yocto BSP          After repo syn is done according to “i.MX_Yocto_Project_User's_Guide.pdf”, Use the command to compile linux BSP, u-boot & kernel source code will be released. # DISTRO=fsl-imx-fb MACHINE=imx7dsabresd source fsl-setup-release.sh -b build-fb # bitbake core-image-base          After compiling is done, u-boot & linux kernel source code is in the path below: u-boot: ~/imx-yocto-bsp/build-fb/tmp/work/imx7dsabresd-poky-linux-gnueabi/u-boot-imx/2017.03-r0/git linux: ~/imx-yocto-bsp/build-fb/tmp/work/imx7dsabresd-poky-linux-gnueabi/linux-imx/4.9.88-r0/git          We can create a new directory for uboot and linux kernel source code. Here I created a directory named disk2. # cd ~/ # mkdir disk2 # cd disk2 # mkdir u-boot-2017-03 # mkdir linux-imx-4.9.88 --Copy u-boot source code to a new directory # cd ~/imx-yocto-bsp/build-fb/tmp/work/imx7dsabresd-poky-linux-gnueabi/u-boot-imx/2017.03-r0/git # cp –r ./* ~/disk2/u-boot-2017-03 --Copy linux kernel source code to a new directory # cd ~/imx-yocto-bsp/build-fb/tmp/work/imx7dsabresd-poky-linux-gnueabi/linux-imx/4.9.88-r0/git # cp –r ./* ~/disk2/ linux-imx-4.9.88 2. Exporting 4.9.88 toolchain from Freescale Yocto BSP (1) Using MACHINE=imx7dsabresd to export the toolchain Step1: # cd ~/imx-yocto-bsp/ # DISTRO=fsl-imx-fb MACHINE=imx7dsabresd source fsl-setup-release.sh -b build-minimal … … Do you accept the EULA you just read? (y/n)  y EULA has been accepted. Welcome to Freescale Community BSP The Yocto Project has extensive documentation about OE including a reference manual which can be found at:     http://yoctoproject.org/documentation For more information about OpenEmbedded see their website:     http://www.openembedded.org/ You can now run 'bitbake <target>' Common targets are:     core-image-minimal     meta-toolchain     meta-toolchain-sdk     adt-installer     meta-ide-support Your build environment has been configured with:     MACHINE=imx7dsabresd     SDKMACHINE=i686     DISTRO=fsl-imx-fb     EULA= BSPDIR= BUILD_DIR=. meta-freescale directory found Here “build-minimal” is a directory for compiling source code, users can also set it other name. In ~/imx-yocto-bsp/build-minimal, Begin to export toolchain with the command. Step2: # DISTRO=fsl-imx-fb MACHINE=imx7dsabresd bitbake core-image-minimal -c populate_sdk [Comment-1] About DISTRO and MACHINE on above 2 commands MACHINE can be set the values below. imx6qpsabreauto imx6qpsabresd imx6ulevk imx6ull14x14evk imx6ull9x9evk imx6dlsabreauto imx6dlsabresd imx6qsabreauto imx6qsabresd imx6slevk imx6solosabreauto imx6solosabresd imx6sxsabresd imx6sxsabreauto imx6sllevk imx7dsabresd imx7ulpevk imx8mqevk   So MACHINE’s value is the name each Evaluation Borad. DISTRO can be set the values below: fsl-imx-x11 - X11 graphics are not supported on i.MX 8. fsl-imx-wayland - Wayland weston graphics. fsl-imx-xwayland - Wayland graphics and X11. X11 applications using EGL are not supported. fsl-imx-fb - Frame Buffer graphics - no X11 or Wayland. Frame Buffer is not supported on i.MX 8 bitbake rootfs type       core-image-minimal       core-image-base       core-image-sato       fsl-image-machine-test       fsl-image-validation-imx       fsl-image-qt5-validation-imx Below is the detailed description for above rootfs type: [Comment-2] Descriptions on difference of toolchain between i.MX6/7 and i.MX8MQ          i.MX6 and i.MX7 are both 32bit ARM processor, they use the same toolchain.          i.MX8MQ is 64bit ARM processor, so it’s toolchain is different from that of i.MX6/7. Setp 3:          After above compiling is done, enter into ~/imx-yocto-bsp/build-minimal/tmp/deploy/sdk # cd ~/imx-yocto-bsp/build-minimal/tmp/deploy/sdk # ls Run .sh file: Then continue operations according to guidance: Done: OK, Let us check /opt/fsl-imx-fb/ directory: # ls /opt/fsl-imx-fb/4.9.88-2.0.0/          Because we used MACHINE=imx7dsabresd, environment was named “cortex-A7”, compiler’s version is still 4.9.88. (2) Using MACHINE=imx6qsabresd to export the toolchain.          We can change “MACHINE=imx6qsabresd” and repeat above 3 steps, environment will be named “cortex-A9”.          Close the current terminal, and open a new one. # cd ~/ imx-yocto-bsp # DISTRO=fsl-imx-fb MACHINE=imx6qsabresd source fsl-setup-release.sh -b build-A9-min            Then automatically enter “~/imx-yocto-bsp/build-A9-min”, run command below. # DISTRO=fsl-imx-fb MACHINE=imx6qsabresd bitbake core-image-minimal -c populate_sdk # ~/imx-yocto-bsp/build-A9-min/tmp/deploy/sdk # ls # ./ fsl-imx-fb-glibc-x86_64-core-image-minimal-cortexa9hf-neon-toolchain-4.9.88-2.0.0.sh   Set it up in another directory: /opt/fsl-imx-fb/4.9.88 (3) Using MACHINE=imx8mqevk to export ARM64 toolchain          Export Toolchain for i.MX8MQ, create a new terminal, then run these 2 commands below. # ~/imx-yocto-bsp # DISTRO=fsl-imx-xwayland MACHINE=imx8mqevk source fsl-setup-release.sh -b build-xwayland # DISTRO=fsl-imx-fb MACHINE=imx8mqevk bitbake core-image-minimal -c populate_sdk Done.          Copy the toolchain to /opt/fsl-imx-fb directory # cd ~/imx-yocto-bsp/build-xwayland/tmp/deploy/sdk # ls #./fsl-imx-fb-glibc-x86_64-core-image-minimal-aarch64-toolchain-4.9.88-2.0.0.sh          I installed it to a new directory: /opt/fsl-imx-fb/4.9.88-arm64 #ls ls /opt/fsl-imx-fb/4.9.88-arm64/  OK, 64bit toolchain for i.MX8MQ has been exported to the directory. 3. Compling u-boot & linux kernel under Stanalone iMX7DSabreSD --Compiling  u-boot for imx7dsabresd # cd ~/disk2/u-boot-2017-03 # source /opt/fsl-imx-fb/4.9.88-2.0.0/environment-setup-cortexa7hf-neon-poky-linux-gnueabi # export ARCH=arm # make clean # make mx7dsabresd_defconfig # make u-boot.imx Done. --Compiling kernel and dtb for imx7dsabresd # cd ~/disk2/linux-imx-4.9.88/ [comment] If environment has been configured, that is, these 2 commands have been run on the current terminal, don’t need to run them again. “source /opt/fsl-imx-fb/4.9.88-2.0.0/environment-setup-cortexa7hf-neon-poky-linux-gnueabi” and “export ARCH=arm” # make clean # make imx_v7_defconfig # make            zImage is in “~/disk2/linux-imx-4.9.88/arch/arm/boot”          dtb is in “~/disk2/linux-imx-4.9.88/arch/arm/boot/dts”            Probably users want to run “make menuconfig”, and meet the errors like below. # sudo apt-get install libncurses*  (To solve the problem below) # make menuconfig [Comment-3]  Users can also use "environment-setup-cortexa9hf-neon-poky-linux-gnueabi" to compile u-boot and kernel. iMX8MQEVK --Compiling u-boot for imx8mqevk # cd ~/disk2/u-boot-2017-03 # source /opt/fsl-imx-fb/4.9.88-arm64/environment-setup-aarch64-poky-linux # export ARCH=arm64 # make clean # make imx8mq_evk_defconfig # make u-boot.imx Done. --Compiling kernel and dtb for imx8mqevk # cd ~/disk2/linux-imx-4.9.88/ [comment] If environment has been configured, that is, these 2 commands have been run on the current terminal, don’t need to run them again. “source /opt/fsl-imx-fb/4.9.88-arm64/environment-setup-aarch64-poky-linux” and “export ARCH=arm64” # make clean # make defconfig # make          Run the command to unset LDFLAGS: # unset LDFLAGS # make Done. 4. Compiling OS Firmware for i.MX7DSabreSD board --u-boot for mfg tools # make mx7dsabresd_config # make u-boot.imx          Then rename u-boot.imx to be “u-boot-mx7dsabresd-mfg.imx”. --kernel and dtb for mfg tools          Copy imx_v7_mfg_defconfig file to “arch/arm/configs”, then run commands below. # make imx_v7_mfg_defconfig # make          zImage will be generated at path arch/arm/boot.          dtb file will be generated at path arch/arm/boot/dts            Then rename zImage to be zImage-mx7dsabre-mfg,          Rename imx7d-sdb.dtb to be zImage-imx7d-sdb-mfg.dtb 5. Copy OS Firmware to the related path of MFG tools          Up to now, 3 files for OS Firmware has been generated, then copy these 3 files to mfgtools\Profiles\Linux\OS Firmware\firmware            When MFG Tools begins to run, these 3 files and ramdisk will be downloaded to SDRAM on board, then run them, and download images(u-boot\kernel\rootfs\)  which have been ready in  “mfgtools\Profiles\Linux\OS Firmware\files”.            Above steps and commands will be performed according to list in ucl2.xml. So customer will add a new list for her downloading or change an existing list according to image’s name. NXP TIC team Weidong Sun 04-25-2019

The document descript how to use the win32diskimager to create bootable sdcard.  How to resize sdcard mirror rootfs partition. Ex: fsl-image-validation-imx-imx6qpdlsolox.sdcard

Basic Linear Algebra Subprograms (BLAS) is a specification that prescribes a set of low-level routines for performing common linear algebra operations such as vector addition, scalar multiplication, dot products, linear combinations, and matrix multiplication. OpenBLAS is an optimized BLAS library which is uesd for deep learning accelerator in Caffe/Caffe2. I enable it in Yocto (Rocko) by adding bb file. And I build on i.MX6QP, i.MX7ULP and i.MX8MQ and also run its test example successfully. You can find test example(openblas_utest) under folder image/opt/openblas/bin of OpenBLAS work directory. Currently, version 0.3.0 is supported in the bb file. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ update to v 0.3.6 and enable mutli-thread by set USE_OPENMP=1 and USE_THREAD=4 when compiling this library.