[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-342729 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-342833 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-342719 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343007 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343017 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-342837 

Pre-Sales: i.MX8/8X applications in automotive(Chinese Version) https://community.nxp.com/docs/DOC-345825 i.MX8X website design resource guide: (Chinese Version) https://community.nxp.com/docs/DOC-345676 After-Sales: i.MX8X memory configuration&test application notes: (Chinese Version) https://community.nxp.com/docs/DOC-345803 i.MX8X hardware design guide: (Chinese Version) https://community.nxp.com/docs/DOC-346582 i.MX8X_4.19.35_bootloader customization application notes: (Chinese Version) https://community.nxp.com/docs/DOC-345713 i.MX8X_4.19.35_kernal customization application notes: (Chinese Version) https://community.nxp.com/docs/DOC-345714 i.MX8X_4.14.98_bootloader customization application notes: (Chinese Version) https://community.nxp.com/docs/DOC-342448 i.MX8X_4.14.98_kernal customization application notes: (Chinese Version) https://community.nxp.com/docs/DOC-344217 i.MX8X_5.4.24_bootloader customization application notes: (Chinese Version) https://community.nxp.com/docs/DOC-347131

L5.4.3_1.0.0 release is now available on IMX_SW landing page: BSP Updates and Releases -> Linux ->Linux L5.4.3_1.0.0. Documentation -> Linux -> Linux 5.4.3_1.0.0 Documentation Files available: # Name Description 1 imx-yocto-LF_L5.4.3_1.0.0.zip i.MX L5.4.3_1.0.0 for Linux BSP Documentation. Includes Release Notes, User Guide. 2 LF_v5.4.y-1.0.0_images_MX6QPDLSOLOX.zip i.MX 6QuadPlus, i.MX 6Quad, i.MX 6DualLite, i.MX 6Solox Linux Binary Demo Files 3 LF_v5.4.y-1.0.0_images_MX6SLLEVK.zip i.MX 6SLL EVK Linux Binary Demo Files 4 LF_v5.4.y-1.0.0_images_MX6UL7D.zip i.MX 6UltraLite EVK, 7Dual SABRESD, 6ULL EVK Linux Binary Demo Files 5 LF_v5.4.y-1.0.0_images_MX7ULPEVK.zip i.MX 7ULP EVK Linux Binary Demo Files  6 LF_v5.4.y-1.0.0_images_MX8MMEVK.zip i.MX 8M Mini EVK Linux Binary Demo Files  7 LF_v5.4.y-1.0.0_images_MX8MNEVK.zip i.MX 8M Nano EVK Linux Binary Demo Files  8 LF_v5.4.y-1.0.0_images_MX8MQEVK.zip i.MX 8M Quad EVK Linux Binary Demo files 9 LF_v5.4.y-1.0.0_images_MX8QMMEK.zip i.MX 8QMax MEK Linux Binary Demo files 10 LF_v5.4.y-1.0.0_images_MX8QXPMEK.zip i.MX 8QXPlus MEK Linux Binary Demo files 11 imx-scfw-porting-kit-1.2.10.1.tar.gz System Controller Firmware (SCFW) porting kit v1.2.10.1 for L5.4.3_1.0.0   Target board: MX 8 Series MX 8QuadXPlus MEK Board MX 8QuadMax MEK Board MX 8M Quad EVK Board MX 8M Mini EVK Board MX 8M Nano EVK Board MX 7 Series MX 7Dual SABRE-SD Board MX 7ULP EVK Board MX 6 Series MX 6QuadPlus SABRE-SD and SABRE-AI Boards MX 6Quad SABRE-SD and SABRE-AI Boards MX 6DualLite SDP SABRE-SD and SABRE-AI Boards MX 6SoloX SABRE-SD MX 6UltraLite EVK Board MX 6ULL EVK Board MX 6ULZ EVK Board MX 6SLL EVK Board   What’s New/Features: Please consult the Release Notes.   Known Issues: For known issues and more details please consult the Release Notes.   More information on changes of Yocto, see: README: https://source.codeaurora.org/external/imx/imx-manifest/tree/README?h=imx-linux-zeus ChangeLog: https://source.codeaurora.org/external/imx/imx-manifest/tree/ChangeLog?h=imx-linux-zeus      

Overview In this doc, I will try to give you a brief of the Linux kernel changes between 4.x and 5.4 (5.0/5.1/5.2/5.3/5.4), which related to i.MX users/developers: Important bug fix and improvements according to my experiences New features you should keep an eye on Interfaces changes may impact applications i.MX up-streaming I cannot make sure every single change's description is 100% correct. Either, I cannot list all of the impacts to the i.MX platform due to my limited knowledge and experiences. I hope this doc can help you on developing kernel drivers, user applications or debugging issues of 5.x i.MX kernel release. Changes Subsystem/Modules Detail changes Comments References Kernel Cores binder: new binderfs, a pseudo-filesystem for the Android Binder IPC driver which can be mounted per-ipc namespace allowing to run multiple instances of Android Hmm... that may imply we can run multi-instance Android without Hypervisor? sysctl: add panic_print sysctl to configure which information to print at panic time, w/ replay option So we can define the panic information for better debugging the crash issue. Also option for users to configure the "panic_print" to replay all dmesg in buffer, some of which they may have never seen due to the loglevel setting, which will help panic debugging How to use boot: Add boot option ( driver_async_probe=... ) to specify drivers to be async probed Asynchronous driver probing can help much on kernel fastboot, and this option can provide a flexible way to optimize and quickly verify async driver probe. Asynchronous device/driver probing support [LWN.net]  swiotlb: add debugfs to track swiotlb buffer usage The device driver will not be able to do dma operations once swiotlb buffer is full, either because the driver is using so many IO TLB blocks inflight, or because there is memory leak issue in device driver. Export buffer usage in debugfs can help. Please note, almost all of the dma buffers on i.MX8 platform comes from swiotlb. aarch64 Linux Kernel Memory Management  New mount syscall API The kernel supports a wide variety of filesystem types, and each has its own, often extensive set of options. As a result, the mount() system call is complex. This makes application code who need mount FS more clear. Six (or seven) new system calls for filesystem mounting [LWN.net]  New APIs to support pidfs clone return pidfs, new syscall pidfd_send_signal(2), which uses file descriptors from /proc/<pid> as stable handles on struct pid.  Toward race-free process signaling [LWN.net]  locking: rwsem improvement unification and simpler micro-optimizations, performance improvement of this locking primitive. Preparations for PREEMPT_RT It's excited that community decided to merge the PREEMPT_RT kernel changes into mainline. It's well known as rt-patch for hard real-time use cases like industry. Index of /pub/linux/kernel/projects/rt/  Memory management KASAN: Improved the KASAN performance for arm64 KernelAddressSANitizer (KASAN) is a dynamic memory error detector. It provides a fast and comprehensive solution for finding use-after-free and out-of-bounds bugs. It's useful when debugging kernel drivers and modules memory issue. The Kernel Address Sanitizer (KASAN) — The Linux Kernel documentation  Fragmentation avoidance improvements, reducing fragmentation events by over 90%. With this change, the page allocator would spread allocations across zones before introducing fragmentation.  We can always found customer's product memory fragment in some use cases in old kernel. Which would cause kmalloc or cma alloc failure and system stop. Balance between zones (i.MX8 we have DMA/NORMAL zones) to avoid fragment is very helpful. patch intro One of customer case(fixed by not using kmalloc): https://jira.sw.nxp.com/browse/MLK-23220  Increase success rates and reduce latency of compaction (physical memory defragmentation) Memory compaction is the way to avoid memory fragment. Memory compaction [LWN.net]  Improve Out Of Memory (OOM) reports, include victim's memcg More clear kernel OOM report may help lot Remove the ancient OOM killer heuristic that preferred to kill children of the "worst" process rather than the process itself Improve the OOM efficiency zram improvements, which can help estimate wasted memory, and perform writeback that will free it zram is actually used very widely in the Android system as backup swap for physical memory. Swap performance is very important. Low RAM Configuration  |  Android Open Source Project  Simplify some of the early memory allocations by replacing usage of older memblock APIs with newer and shinier ones memblock API changes. If you used memblock in your drivers, then need to check. Boot time memory management — The Linux Kernel documentation  psi: Improves the Pressure Stall Information resource monitoring With this mechanism, Android can monitor for, and ward off, mounting memory shortages before they cause problems for the user. For example, using memory stall, monitors in userspace like the low memory killer daemon (lmkd) can detect mounting pressure and kill less important processes. Supported in Android10, replace the vmpressure. Low Memory Killer Daemon (lmkd)  |  Android Open Source Project  Pressure stall monitors [LWN.net]  Improve vmap allocation Speed up the vmalloc https://lkml.org/lkml/2018/10/19/786  Introduce madvise() flags MADV_COLD, MADV_FREE, MADV_PAGEOUT MADV_COLD marks pages as inactive (thus more easily reclaimed under memory pressure), but doesn't discard the contents like MADV_FREE does, and MADV_PAGEOUT , which reclaims pages immediately. Android would use this flags for better memory management kernel/git/torvalds/linux.git - Linux kernel source tree  memcg: from v1->v2 shrink all memcg caches for the slab cache Throttle allocators when reclaim cannot keep up with v2 memory.high limit Introduce gradual reclaim pressure..... Control Group v2 — The Linux Kernel documentation  Block layer Boot to a device-mapper device without initramfs DM is widely used, you can not bootup to DM rootfs directly. Android 10 would use dynamic partition by creating super partition for /system, /vendor of dm-linear Implementing Dynamic Partitions  |  Android Open Source Project  Tracing and Perf Perf: lots of improvement TBD Security security: Create "kernel hardening" config area Help mitigate kernel vulnerabilities and find bugs in kernel drivers, like Stack buffer overflow mitigation, Hardened usercopy Kernel Hardening  |  Android Open Source Project  LSM: Add kernel lockdown functionality When enabled, the new "lockdown" feature will restrict some kernel functionality, even for the root user, making it harder for compromised root accounts to compromise the rest of the OS Kernel lockdown in 4.17? [LWN.net]  Networking Enable MSG_ZEROCOPY for udp sockets Improve the UDP sending performance. Pay attention that the zero copy UDP sockets only limit to the send operations, not receive. Also require application code change, not efficient at small MTU. Zero-copy networking [LWN.net]  ARM/ARM64 New SoCs: i.MX7ULP with EVK i.MX8MQ with EVK i.MX8MM  i.MX8QXP perf vendor events: Add Cortex-A57 and Cortex-A72 events  support all ARMv8 recommended events Make CONFIG_ZONE_DMA32 configurable commit Which means you can remove the DMA zone, and use only one single normal zone in kernel. Drivers drm: Initial merge of timeline sync objects Timeline syncobj gives user more flexibility and convenience to do sychronization. Android does not used. Staging driver: i.MX7 MIPI CSI subdev NXP QuadSPI driver Introduce Sound Open Firmware (SOF) for audio DSP devices Big changes to the current HiFi4 DSP (in i.MX8QM/QXP) infrastructure. The SOF is an open source audio DSP firmware and SDK that provides audio firmware infrastructure and development tools. Also integrated with current kernel alsa subsystem.  Home - Sound Open Firmware  Firmware - AlsaProject  How to build i.MX8 HiFi4 firmware Add NXP SJA1105 DSA network driver with ptp support Used for networking switch Add TJA11xx PHY driver Add lpspi driver support fsl_lpuart: add imx8qxp support Add SCU watchdog/RTC support regmap: add i3c bus support commit Means we can have i3c bus support in regmap now. References Linux_Kernel_Newbies - Linux Kernel Newbies  Welcome to LWN.net [LWN.net]  kernel/git/torvalds/linux.git - Linux kernel source tree 

Recently many customers faced the issue about connecting the git.freesacle .com failed when they built old bsp version like 4.1.15 or 3.14.52,  when the customer repo init according to the yocto user guide, they get the error message like ： repo init -u git://git.freescale.com/imx/fsl-arm-yocto-bsp.git -b imx-4.1-krogoth manifests:  escale.com[0: 192.88.156.202]: errno=Connection refused  fatal: cannot obtain manifest git://git.freescale.com/imx/fsl-arm-yocto-bsp.git ///// git clone git://git.freescale.com:9418/imx/fsl-arm-yocto-bsp.git -b imx-4.1.15-1.0.0_ga Cloning into 'fsl-arm-yocto-bsp'... fatal: unable to connect to git.freescale.com: git.freescale.com[0: 192.88.156.202]: errno=Connection refused the reason is that the old bsp source code was moved to "https://source.codeaurora.org/external/imx", customer needs to change "git://git.freescale.com/imx"  to "https://source.codeaurora.org/external/imx", for new repo init commands, try to use the commands like “repo init -u https://source.codeaurora.org/external/imx/fsl-arm-yocto-bsp -b <branch> [-m <manifest>]” for example: 4.1.15_1.0.0: repo init -u https://source.codeaurora.org/external/imx/fsl-arm-yocto-bsp -b imx-4.1.15-1.0.0_ga 4.1.15_2.0.0: repo init -u https://source.codeaurora.org/external/imx/fsl-arm-yocto-bsp -b imx-4.1-krogoth -m imx-4.1.15-2.0.0.xml 4.1.15_2.1.1: repo init -u https://source.codeaurora.org/external/imx/fsl-arm-yocto-bsp -b imx-4.1-krogoth -m imx-4.1.15-2.1.1.xml then you can "repo sync" and "bitbake", but some customers still has the connection error on building firmware-imx package, the error message like : ERROR: firmware-imx-1_5.4-r0 do_fetch: Fetcher failure: Fetch command failed with exit code 128, output: Cloning into bare repository '/opt/yocto/fsl-release-bsp/downloads//git2/git.freescale.com.imx.imx-firmware.git'... fatal: unable to connect to git.freescale.com: git.freescale.com[0: 192.88.156.202]: errno=Connection refused ERROR: firmware-imx-1_5.4-r0 do_fetch: Function failed: Fetcher failure for URL: 'git://git.freescale.com/imx/imx-firmware.git;branch=master;destsuffix=/opt/yocto/fsl-release-bsp/fsl_build_x11/tmp/work/cortexa9hf-neon-mx6qdl-poky-linux-gnueabi/firmware-imx/1_5.4-r0/firmware-imx-5.4/git'. Unable to fetch URL from any source. this reason is that 4.1.15 needs to download git2 package from git.freescale.com, then I uploaded the firmwar-imx git2 package, try to unzip first, then put packages under downloads/git2, then "bitbake firmware-imx" again

[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-343054 

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

We will cross compile L5.4.3_1.0.0 on ubuntu18.04 LTS platform in three steps. 1. Installing Ubuntu 18.04 to vmplayer14 & Configuring Ubuntu 18.04 LTS 2. Compiling L5.4.3_1.0.0 BSP According to Steps in i.MX_Yocto_Project_User's_Guide.pdf 3. Handling tensorflow-lite compilation errors. --BEGIN No.1 Installing Ubuntu 18.04 to vmplayer14 & Configuring Ubuntu 18.04 LTS 1. Install 18.04 on vmplayer After installation is done, root user should be set at first. # sudo passwd root Then follow these steps to configuration ubuntu 18.04 for environment of compiliation --Changing sources of ubuntu 18.04 mirror If you are Chinese users, you can do the step, which can improve your system performance. # sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak # sudo geit /etc/apt/source.list Comment I.MX customers outside China do not need to modify Ubuntu source list, or can modify it to local mirror site of Ubuntu 18.04, which can improve the speed of software upgrade. Delet all sources and copy following lines here, Then save it and exit Update ubuntu source deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse # deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse # deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse Then running these 2 commands to update sources and packages # sudo apt-get update # sudo apt-get upgrade 2. Installing packages for compiliation Packages For Compiling BSP # sudo apt-get install flex bison gperf build-essential zlib1g-dev lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z1-dev libgl1-mesa-dev tofrodos python-markdown libxml2-utils xsltproc # sudo apt-get install uuid-dev:i386 liblzo2-dev:i386 gcc-multilib g++-multilib subversion openssh-server openssh-client uuid uuid-dev zlib1g-dev liblz-dev lzop  liblzo2-2 liblzo2-dev git-core curl # sudo apt-get install u-boot-tools mtd-utils android-tools-fsutils openjdk-8-jdk device-tree-compiler aptitude libcurl4-openssl-dev nss-updatedb # sudo apt-get install chrpath texinfo gawk cpio diffstat No.2 Compiling L5.4.3_1.0.0 BSP According to Steps in i.MX_Yocto_Project_User's_Guide.pdf          The detailed BSP compilation steps are given in i.MX_Yocto_Project_User's_Guide.pdf. Here are just some tips and simple steps. For Chinese customers, the system may not respond when the repo init or repo sync command is executed after obtaining the repo script. Detailed description is below: (1)Getting repo script # mkdir ~/bin (this step may not be needed if the bin folder already exists) # curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo # chmod a+x ~/bin/repo # export PATH=~/bin:$PATH (2)Getting Yocto source # mkdir imx-yocto-bsp # cd imx-yocto-bsp # repo init -u https://source.codeaurora.org/external/imx/imx-manifest -b imx-linux-zeus -m imx-5.4.3-1.0.0.xml # repo sync          After running repo init or repo sync, you may encounter a situation where there is no progress for a long time, and repo sync stops there without any prompt. This may be caused by googlesource site being inaccessible.          At this time, you can modify the googlesource URL to the URL of Tsinghua University. # gedit ./repo          Changing REPO_URL = 'https://gerrit.googlesource.com/git-repo'          To be:                    REPO_URL = 'https://mirrors.tuna.tsinghua.edu.cn/git/git-repo'          Save and exit. Then run “repo init -u https://source.codeaurora.org/external/imx/imx-manifest -b imx-linux-zeus -m imx-5.4.3-1.0.0.xml”. or repo sync No.3 Handling tensorflow-lite compilation errors       If you encounter a tensorflow-lite compilation error during the compilation process, the following processing methods may be helpful to you. Cause Analysis:          Compiling tensorflow-lite requires three steps: fetching packages, configuring environment, and compiling code.          During the configuring environment, the following 8 software packages need to be downloaded. If any of the 8 files are not successfully downloaded, an error will be reported and compilation will be terminated.          ①9f48e814419e.tar.gz          ②38ebac7b059e84692f53e5938f97a9943c120d98.zip          ③release-1.8.0.tar.gz          ④389ec3f906f018661a5308458d623d01f96d7b23.tar.gz          ⑤master.zip          ⑥816a4ae622e964763ca0862d9dbd19324a1eaf45.tar.gz          ⑦1f5eae5d6a135ff6811724f6c57f911d1f46bb15.tar.gz          ⑧fft.tgz          If you encounter this problem, you can refer to the following methods to solve it. Open the file with editor: ~/imx-yocto-bsp/build-xwayland/tmp/work/aarch64-poky-linux/tensorflow-lite/1.13.2-r0/git/tensorflow/lite/tools/make/download_dependencies.sh URLs EIGEN_URL="https://bitbucket.org/eigen/eigen/get/9f48e814419e.tar.gz" GEMMLOWP_URL="https://github.com/google/gemmlowp/archive/38ebac7b059e84692f53e5938f97a9943c120d98.zip" GOOGLETEST_URL="https://github.com/google/googletest/archive/release-1.8.0.tar.gz" ABSL_URL="https://github.com/abseil/abseil-cpp/archive/389ec3f906f018661a5308458d623d01f96d7b23.tar.gz" NEON_2_SSE_URL="https://github.com/intel/ARM_NEON_2_x86_SSE/archive/master.zip" FARMHASH_URL="https://github.com/google/farmhash/archive/816a4ae622e964763ca0862d9dbd19324a1eaf45.tar.gz" FLATBUFFERS_URL="https://github.com/google/flatbuffers/archive/1f5eae5d6a135ff6811724f6c57f911d1f46bb15.tar.gz" FFT2D_URL="http://www.kurims.kyoto-u.ac.jp/~ooura/fft.tgz" Save and exit. [comment]     Don’t run “bitbake tensorflow-lite -c cleanall before you modify it”, otherwise files will be deleted.  Then try to compile tensorflow-lite like below: # bitbake tensorflow-lite -c compile   At the same time, we can open this directory and check if the following directories are created. If these 8 directories are successfully created, it means that links we modified are no problem.          After tensorflow-lite is successfully built, we can continue to compile full images. # bitbake imx-image-full --END NXP TIC team Weidong Sun 2020/3/30

-BACKGROUND       Since the release of i.MX8MQ and i.MX8M Mini, some customers have submitted questions about the design of USB2.0 for these two processors: due to the needs of the project, there is no need to use USB3.0 and USB TYPE-C. Therefore, these applications need to use a conventional USB2.0 interface design similar to i.MX6Q.       In order for customers with similar needs to complete the design smoothly, this document summarizes the answers to previous customer responses and draws two USB2.0 design schematics. At the same time, the i.MX expert hardware team member helped review these two drawings, and the i.MX Expert software team gave suggestions on software adjustments. -BEGIN       i.MX8MQ supports USB3.0 and is compatible with USB2.0, i.MX8M Mini only supports USB2.0, not USB3.0. In both development boards, the USB TYPE-C design scheme is used. We must remove the USB TYPE-C, PD chip and logic chip. At the same time, change the connector to MicroUSB and USB TYPE-A-F. No.1 Hardware Design 1. IOMUX list 2 、USB circuit design (1) USB Power & OC control I.MX8MM i.MX8MQ                                                 i.MX8MQ                                              i.MX8MQ [Comment] For i.MX8MQ -USB1 is configured as Dual Role Mode, USB1 OTG ID is used for detection -USB2 is configured as fixed Host mode, USB2 OTG ID is used for detection -i.MX8M Mini USB2.0                                        i.MX8M Mini                                     i.MX8M Mini [Comment] For i.MX8M Mini -USB1 is configured as Dual Role Mode, USB1 OTG ID is used for detection -USB2 is configured as fixed Host mode, USB2 OTG ID is used for detection (3) Additional description --About USB1_VBUS & USB2_VBUS of i.MX8M Mini          According to i.MX8M Mini datasheet, USB1_VBUS & USB2_VBUS allows 0~3.9V input. See below, please! Therefore, some customers have questioned the USB1_VBUS on the I.MX8M Mini-EVK. From the drawings, the external input voltage exceeds this range.          In fact, customers do not need to worry about this problem. There are internal voltage-dividing resistors on the USB1_VBUS and USB2_VBUS pins. As long as the customer refers to the design method on the I.MX8M Mini-EVK, the input voltage of these 2 pins can be guaranteed Inside. --About USBx OTG ID & USBx_ID (1) USBx_OTG_ID          USBx OTG ID is also called GPIO ID, which is the same as that of i.MX6Q. During the work process, the software changes the role between device and host according to the level of the ID pin from high to low or from low to high. (2)USBx_ID          USBx_ID is called USB PHY ID, which can also perform the same function as USBx OTG ID. (3)Using USBx_OTG_ID or USBx_ID          USBx_OTG_ID is recommended. But if customer wants to use USBx_ID, for i.MX8MQ, she can configure USB_CTL0_ADDR[utmiotg_iddig_sel] register. And for I.MX8M Mini, USBNC_n_CTRL2[DIG_ID_SEL] register. [Comment]          The configuration is got from reference manual of these 2 processors, due to no suitable board, this configuration is not validated on board. Customers can try it. (4) About Flashing Images to the Storage of Board          For an empty board or a board that requires an update image, we need to use the USB interface to program the image. At this time, we need the USB interface to work in device mode. For this, the ROM CODE inside the CPU will ensure that the USB works in device mode. No.2 Tuning Software 1.IOMUX According to the actual application, the signals to be used are multiplexed in the dts file. This step is relatively simple and will not be described here 2. Tuning USB configuration in u-boot / device tree For i.MX8M Mini & i.MX8MQ, i.MX Expert softer team gives the following suggestions, I quote their suggestions here:       Customer can try it by removing CONFIG_USB_TCPC in imx8mm_evk_defconfi and well as removing the typec_ptn5110_1/2 dependencies in the fsl-imx8mm-evk.dts. The uboot does check the state of the Type C ICs and crash or gets stuck if they are removed. --i.MX8M Mini U-BOOT:  CONFIG_USB_TCPC=n Device Tree: &usbotg1 {     status = "okay"; }; &usbotg2 {     status = "okay"; --------------------------------------------------------- --i.MX8MQ --u-boot CONFIG_USB_TCPC=n --Node of Device tree &usb_dwc3_0 {              status = "okay";              /*extcon = <&typec_ptn5100>;*/              dr_mode = "otg";              hnp-disable;              srp-disable;              adp-disable;              maximum-speed = "high-speed"; }; ---------------------------------------------- -END [Comment] If you encounter problems while using this document, please submit a ticket to me. Here are the steps to submit a ticket: 1. Open below SUPPORT site, click blue "Go to Tickets" in the middle. http://www.nxp.com/support/support:SUPPORTHOME 2.Then you will be requested to Login, if you have no an account, please first Register with your business email. 3.After login, please "Create New Cases" button in the middle, then you can submit your question. NXP TIC team Weidong Sun 2020/3/30

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343059 

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343113