本文旨在说明基于i.MX8X如何设计硬件平 台，包括相关设计资源的收集与学习，硬件原 理图设计，layout，启动(bring up)，量产准备， 及正式量产后的失效分析与失效控制。主要是 帮助厘清硬件开发相关从头到尾的问题。 请注意本文为培训和辅助文档，部分内容源 自PMIC/i.MX8X硬件开发指南，并作中文翻 译，强调重点，和查缺补漏，本文不是官方文 档的替代，请一切以官方文档为准。 目录： i.MX8X硬件参考平台 ................................................. 3 2 i.MX8X硬件设计资源 ................................................. 5 i.MX8X芯片相关设计资源 ............................................... 5 i.MX8QXP MEK板外设相关设计资源 ........................... 10 i.MX8QXP 硬件接口规范 .............................................. 11 3 i.MX8X原理图设计检查点 ........................................ 13 PMIC+i.MX8X供电能力和上电时序 .............................. 13 PMIC电源输出端设计 ................................................... 17 I.MX8X电源输入端及去耦设计 ..................................... 22 LPDDR4内存设计 ........................................................ 23 DDR3L内存设计 ........................................................... 25 I2C总线设计 ................................................................. 26 Reset，Wdog reset和On/Off设计建议 ......................... 27 PCIe设计 ...................................................................... 29 USB设计 ...................................................................... 30 晶体时钟设计 ............................................................... 32 JTAG信号端接设计 ...................................................... 34 未使用接口管脚的端接处理 .......................................... 35 GPIO管脚的设计策略 ................................................... 37 调试接口建议 ............................................................... 37 4 i.MX8X 布线设计检查点 ........................................... 40 PMIC电源输出端布线建议 ............................................ 40 i.MX8X端去耦电容摆放 ................................................ 41 电源布线建议 ............................................................... 41 PCB叠层建议 ............................................................... 43 内存布线通用建议 ........................................................ 43 LPDDR4内存布线建议 ................................................. 44 DDR3L内存布线建议.................................................... 45 内存信号完整性仿真建议 ............................................. 47 内存JEDEC信号兼容性测试 ......................................... 48 高速电路板布线建议..................................................... 49 时钟建议 ...................................................................... 50 信号线阻抗建议 ............................................................ 53 USB布线建议 ............................................................... 54 5 i.MX8X硬件散热设计 ............................................... 54 6 i.MX8X硬件启动bring up .......................................... 56 Bring up需要参考的文档与使用工具............................. 56 i.MX8X Bring up需要准备的文档与使用工具 ............................. 60 Bring up检查列表 .......................................................... 65 7 试产与量产前检查点 ................................................. 67 内存稳定性 ................................................................... 67 ESD与EMI考虑 ............................................................. 68 产线设计 ....................................................................... 69 8 i.MX8X失效分析流程 ................................................ 70 NXP失效分析服务 ........................................................ 70 NXP FA失效分析流程 ................................................... 70 筛查是否是芯片原生问题 .............................................. 72 9 量产厂线的EOS/ESD控制 ........................................ 73 什么是EOS/ESD ........................................................... 73 设计中的EOS/ESD风险检查点 ..................................... 75 生产产线中的EOS/ESD风险与防护 .............................. 78

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.

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-341641 

The i.MX28 family of multimedia applications processors is the latest extension of Freescale's ARM9 product portfolio. The i.MX28 family integrates display, power management, and connectivity features unmatched in ARM9-based devices, reducing system cost and complexity for cost sensitive applications. It also integrates CAN, USB and Ethernet connectivity with full AEC-Q100 automotive qualification for automotive applications. i.MX Family Comparison Product Information on Freescale.com i.MX280 i.MX280 Multimedia Applications Processor i.MX281 i.MX281 Multimedia Applications Processor i.MX283 i.MX283 Multimedia Applications Processor i.MX285 i.MX285 Multimedia Applications Processor i.MX286 i.MX286 Multimedia Applications Processor i.MX287 i.MX287 Multimedia Applications Processor Evaluation/Development Boards and Systems MCIMX28EVKJ: i.MX28 Evaluation Kit How to add support for a new NAND How to add a New on imx28 with Win CE Running a mainline kernel on a MX28EVK board How to enable SPI NOR boot for iMX28 (Spansion s25fl256s) Embedded Software and Tools Android OS for i.MX Applications Processors i.MX28 Software and Development Tool Resources Additional Resources Adding Support For a New NAND with i.MX28–NAND Analysis Adding Support For a New NAND with i.MX28 on Win CE Board bring-up and DDR initialization tools i.MX as a USB Playback/Capture Device on One OTG Port i.MX28: GPIO interrupt on both rising and falling edges How to enable SPI NOR boot for iMX28 (Spansion s25fl256s) Running a Mainline Kernel on an i.MX28 EVK Board Running mk_mx28_sd on Ubuntu 12.04 Ubuntu 12.04 64-bit Precise Pangolin Host Setup for Building i.MX28 L2.6.35_MX28_SDK_10.12_SOURCE Use LCD_D11 pin for enet reset in iMX28

In defaut Linux BSP, NXP implemented LVDS to HDMI(it6263) and MIPI-DSI to HDMI(adv7535) bridge chip drivers. And these drivers need read the EDID from display, then apply the timing parameters to DRM driver. But for the use case that bridge chip -> Serializer -> Deserializer -> LCD Panel use case, there is no EDID. The attached are reference patches for such use case, it combined the bridge chip to panel directly, and no EDID is needed. The patches are tested on iMX8QXP MEK with bridge chip + panel mode, both of them can see the fb0 device under /sys/class/graphics/ folder, also can see card under  /sys/class/drm/. Display works fine with DTS selected 720P panel mode. [2020-06-24]: Add patches for L4.14.98 kernel: Android_Auto_P9.0.0_GA2.1.0_Kernel_No_EDID_IT6263.patch L4.14.98-iMX8QXP-MEK-ADV7535-MIPI-DSI-to-HDMI-bridge-chip-com.patch

Although you can develop your own driver to control GPIOs inside kernel space, there is a much simpler way for accessing GPIOs from user space. When timing requirements are not an issue, you are able to use GPIO-SYSFS. SYSFS is a virtual file system that exports some kernel internal framework functionalities to user space and GPIO is one of the frameworks that can have functionalities exported through SYSFS. The GPIO-SYSFS feature is available in all mainline kernels from 2.6.27 onwards. Configuring Kernel to export GPIO through SYSFS To enable GPIO in SYSFS, select the following kernel option: Device Drivers --->       --- GPIO Support             [*] /sys/class/gpio/... (sysfs interface) If you are using i.MX233 or i.MX28, after recompiling the kernel, do not forget to generate boot streams again, because this is not automatic even in ltib. Be sure that the pins you will try to use are really accessible as GPIO pins and were not requested by the kernel (gpio_request). If pin was gpio_request'ed, you will need to gpio_export the same pin inside the kernel in order to have it accessible through SYSFS. If pin is not set as GPIO by default, you will need to set IO MUX in the proper file inside <kernel>/arch/arm/mach-XXX. Accessing GPIO in user space After enabling GPIO-SYSFS feature, you can boot your device with the new kernel to make some tests. First you need to export the GPIO you want to test to the user space: echo XX > /sys/class/gpio/export XX shall be determined by the following algorithm: GPIOA_[B] is the GPIO you want to export, where "A" is the GPIO bank and "B" is the offset of the pin in the bank. if the first available GPIO bank is 0 // (iMX.28, for example)     XX = A*32 + B; else // first GPIO bank is 1     XX = (A-1)*32 + B; After exporting a GPIO pin, you shall be able to see the GPIO interface exported to: /sys/class/gpio/gpioXX Through this interface, you are now able to do things like: # Reading the pin value cat /sys/class/gpio/gpioXX/value # Changing pin direction echo in > /sys/class/gpio/gpioXX/direction echo out > /sys/class/gpio/gpioXX/direction # Toggling GPIO output level echo 0 > /sys/class/gpio/gpioXX/value echo 1 > /sys/class/gpio/gpioXX/value It is important to note that through the GPIO virtual filesystem it is only possible to deal with one GPIO pin at a time (per command).

When working with IPU applications, sometimes image format converter is needed to check images generated by IPU that are not readable by PC (e.g. RGB565, common i.MX framebuffer format -> png or jpg) or generate a RGB picture from an encoded file to be read by IPU (e.g. png -> RGB565 framebuffer). There are some useful tools on Linux and some also available on Windows that can perform these conversions. I listed 5 tools with some usage examples below. IMAGEMAGICK // Display a 800x600 rgb image display -size 800x600 -depth 8 rgb:output.rgb // Show information of output.rgb identify -size 1296x972 -depth 8 output.rgb // Convert a 640x480 grayscale raw rgb file to png convert -size 640x480 -depth 8 imagefile.rgb image.png // To list all available color formats identify -list format For more information about Imagemagick and its format support. access: http://www.imagemagick.org/script/formats.php FFMPEG // List available formats for ffmpeg ffmpeg -pix_fmts // Convert raw rgb565 image to png ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt rgb565 -s 1024x768 -i freescale_1024x768.raw -f image2 -vcodec png screen.png // Convert png to raw rgb565 ffmpeg -vcodec png -i image.png -vcodec rawvideo -f rawvideo -pix_fmt rgb565 image.raw // Convert a 720x480 NV12 (YUV 420 semi-planar) image to png ffmpeg -s 720x480 -pix_fmt nv12 -i image-nv12.yuv -f image2 -pix_fmt rgb24 image-png.png // Convert a 640x480 uyvy422 image to png ffmpeg -s 640x480 -pix_fmt uyvy422 -i image-uyvy422.yuv -f image2 -pix_fmt rgb24 image-uyvy422.png MENCODER http://www.mplayerhq.hu/DOCS/HTML/en/encoding-guide.html TRANSCODING http://www.transcoding.org/cgi-bin/transcode?Examples GRAPHICSMAGICK http://www.graphicsmagick.org/

Freescale does not have a specific GStreamer element to do JPEG encoding, so the standard 'jpegenc' should be used. Image Capture With a web camera gst-launch v4l2src num-buffers=1 ! jpegenc ! filesink location=sample.jpeg With an embedded camera gst-launch mfw_v4lsrc num-buffers=1 !  jpegenc ! filesink location=sample.jpeg More pipelines on GStreamer i.MX6 Pipelines

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-343116 

Introduction The NFC Reader Library is a feature complete software support library for NXP's NFC Frontend ICs. It is designed to give developers a faster and simpler way to deliver NFC-enabled products. This multi-layer library, written in C, makes it easy to create NFC based applications. The purpose of this document is to provide instructions on how to install the NFC Reader Library on imx7dsabresd and communicate with PN5180, a NFC frontend. It will describe all the steps required to connect the board to an OM25180TWR, the wire connections, the changes in the device tree, and the library configuration. Building the Linux image and the Bal kernel module This section describes how to build the Linux image using Yocto and how to compile the Bal kernel module. Informations specific for this library start from the next section. Requirements: a Linux host PC (ex. Ubuntu 14.04/16.04) and root permissions. To download the required host packages, use: $ sudo apt-get install gawk wget git-core diffstat unzip texinfo gcc-multilib build-essential chrpath socat libsdl1.2-dev Specific for Ubuntu: $ sudo apt-get install libsdl1.2-dev xterm sed cvs subversion coreutils texi2html docbook-utils python-pysqlite2 help2man make gcc g++ desktop-file-utils \ libgl1-mesa-dev libglu1-mesa-dev mercurial autoconf automake groff curl lzop asciidoc To setup the repo utility (a tool written on top of git), run the commands: $ mkdir ~/bin (this step may not be needed if the bin folder already exists) $ curl http://commondatastorage.googleapis.com/git-repo-downloads/repo > ~/bin/repo $ chmod a+x ~/bin/repo Then add the following line to .bashrc to ensure the ~/bin is in the PATH variable. export PATH=~/bin:$PATH To download the Freescale Yocto Project Community BSP: $ mkdir fsl-release-bsp $ cd fsl-release-bsp $ repo init -u git://git.freescale.com/imx/fsl-arm-yocto-bsp.git -b imx-4.1-krogoth $ repo sync To build the image, in the fsl-release-bsp run the commands: $ mkdir buildDevSpi $ DISTRO=fsl-imx-xwayland MACHINE=imx7dsabresd source fsl-setup-release.sh -b buildDevSpi $ bitbake fsl-image-machine-test To build the toolchain, run: $ bitbake meta-toolchain $ cd buildDevSpi/tmp/deploy/sdk/ $ ./fsl-imx-xwayland-glibc-x86_64-meta-toolchain-cortexa7hf-neon-toolchain-4.1.15-2.1.0.sh Accept the default parameters. In order to deploy the image on an SD card use: $ sudo dd if=fsl-image-machine-test-imx7dsabresd.sdcard of=<sd card> bs=1M && sync The image is found in buildDevSpi/tmp/deploy/images/imx7dsabresd. For the kernel module compilation, setup the console environment: $ . /opt/fsl-imx-xwayland/4.1.14-2.1.0/environment-setup-cortexa7hf-neon-poky-linux-gnueabi Then, in the kernel module directory, replace the path with your linux build directory in the Makefile and run: $ make The bal.ko is the compiled module. To use the kernel menuconfig, run: $ bitbake -c menuconfig linux-imx Another useful command, for rebuilding the linux kernel image, is: $ bitbake -f -c compile linux-imx; bitbake -f -c deploy linux-imx; bitbake -f -c compile fsl-image-machine-test; bitbake -f fsl-image-machine-test Host interface The interface of the PN5180 to a host is based on a SPI interface, extended by the signal line BUSY. Only half-duplex data transfer is supported and no chaining is allowed, meaning that the whole instruction has to be sent, or the whole receiver buffer has to be read out. The module is connected to the i.MX7D board using the mikro bus expansion port in the following way: MK_BUS_CS, MK_BUS_SCK, MK_BUS_MOSI, MK_BUS_MISO are used for the SPI bus lines. MK_BUS_INT, MK_BUS_RX, MK_BUS_TX are used for the BUSY, RESET and IRQ lines. The pin configuration will be the following: GPIO6_IO22 will be the CS, GPIO6_IO14 will be BUSY, GPIO_IO12 will be RESET and GPIO_IO13 will be IRQ. The DWL pin, which can be used for firmware update, will be connected to GND. A common ground is also required. Connections table: Jumper Jumper Pins Description i.MX7D I/O Tower Edge J4 1 - 2 SPI Clk Selection ECSPI3_SCLK (SAI2_RX_DATA) B7 J20 1 - 2 PN5180 Reset GPIO6_IO12 (SAI1_RX_DATA) B8 J1 1 - 2 SPI SS0 GPIO6_IO22 (SAI2_TX_DATA) B9 J3 1 - 2 SPI MOSI ECSPI3_MOSI (SAI2_TX_BCLK) B10 J2 1 - 2 SPI MISO ECSPI3_MISO (SAI2_TX_SYNC) B11 J19 2 - 3 PN5180 BUSY GPIO6_IO14 (SAI1_TX_SYNC) B58 J5 1 - 2 PN5180 IRQ GPIO6_IO13 (SAI1_TX_BCLK) B62 X X PN5180 DWL GND B52 X X GND GND B2 Kernel Configuration In order to allow the library to manage the RESET, IRQ and BUSY pins, the options for Debug GPIO and Userspace I/O drivers must be enabled (in menuconfig, Device Drivers -> GPIO Support -> Debug GPIO and Device Drivers -> Userspace I/O -> Userspace I/O platform driver with generic IRQ). For controlling the SPI, there are two options: spidev or NXP bal. For spidev, it is necessary to select Device Drivers -> SPI support -> User mode SPI and apply the imx7d-sdb_spidev.patch (it also does the pinmuxing, it is attached to the document). When using NXP bal, it is necessary to compile the module, initialize it with insmod and apply the imx7d-sdb_bal.patch (it also does the pinmuxing, the patch and the module are attached to this document). Library Configuration For the library configuration, <lib-folder>/Platform/DAL/Board_Imx6ulevkPn5180.h must be replaced with Board_Imx7dsabresdPn5180_bal.h or Board_Imx7dsabresdPn5180_spidev.h (based on the selected spi interface). For compilation, the command is: $ ./build.sh yocto /opt/fsl-imx-xwayland/4.1.15-2.1.0/sysroots/ The last parameter is the location of the toolchain generated by yocto. A build folder is generated outside of the source code folder. The applications from the ComplianceApp can be deployed on the board in order to test the functionality provided. Other useful resources: – i.MX Yocto Project User's Guide: https://www.nxp.com/webapp/sps/download/preDownload.jsp?render=true – NFC Reader Library for Linux Installation: https://www.nxp.com/docs/en/application-note/AN11802.pdf – PN5180 component: https://www.nxp.com/docs/en/data-sheet/PN5180A0XX-C1-C2.pdf

The attached document describes how to integrate the souphttpsrc plugin and make it work.

The customer would like to test BT.656 using Test mode. Is it supported? 38.4.3.3 Test mode in RM shows only one CSIx_SENS_CONG setting. Does it mean Test mode support only one as follows? Does Test mode support other settings? CSIx_EXT_VSYNC = 0x1 CSIx_DATA_WIDTH = 0x1 CSIx_SENS_DATA_FORMAT = 0x0 CSIx_PACK_TIGHT = 0x0 CSIx_SENS_PRTCL = 0x1 CSIx_SENS_PIX_CLK_POL = 0x1 CSIx_DATA_POL = 0x0 CSIx_HSYNC_POL = 0x0 CSIx_VSYNC_POL = 0x0 For example, customer want to know if Test mode support  CSIx_SENS_PRTCL=0x2or 0x3 instead of 0x1? customer want to know if Test mode support CSIx_SENS_DATA_FORMAT=0x1or 0x2 instead of 0x0? Answer: CSI CM TEST MODE is working as below: 1,only ungated mode. 2,data width should be configured to 8 3,data format should be configured to rgb888 It cannot be other format such as bt656. It uses CSI1_TST_CTRL register to configure {R,G,B} 24 bit value and taking it as RGB888/YUV444 format for further process.  The generated image size is due to the configured width & height in the registers.

Important: If you have any questions or would like to report any issues with the DDR tools or supporting documents please create a support ticket in the i.MX community. Please note that any private messages or direct emails are not monitored and will not receive a response.   This is a detailed programming aid for the registers associated with MMDC initialization. The last sheet formats the register settings for use with ARM RealView ICE. It can also be used with the windows executable for the DDR Stress Test. This programming aid was used for internal NXP validation boards.

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-344579 

Hardware connection: there are two board-to-board connectors on E-INK daughter card IMXEBOOKDC4, while there is only one on i.MX7D Sabre board, as the picture below. This might be a bit confusing to connect the two: Checked with internal, the original design was trying to wire both eLCDIF and EPDC bus out to one daughter card, add the flexibility to have different configurations on one display daughter card(LCD/EPD). On i.MX7D Sabre board, only one connector is available for EPDC bus. Here is how we connect i.MX7D Sabre and IMXEBOOKDC4: Software setup: here we use pre-build L3.14.38_6UL7D_Beta Linux as our boot-image, steps to setup/boot/test EPDC: 1. download and decompress BSP pre-build image package "L3.14.38_beta_images_MX6UL7D.tar.gz", you should be able to find the SD image in it -- "fsl-image-gui-x11-imx7dsabresd.sdcard" 2. program the SD image on your SD card(>800 MBytes) with command(I'm running this in Ubuntu): "dd if=fsl-image-gui-x11-imx7dsabresd.sdcard of=/dev/sdb;sync" 3. insert SD card to the slot(J6) on i.MX7D Sabre board, connect debug-UART and power-on the board 4. modify the u-boot environment variables as below:      a.) setenv fdt_file imx7d-sdb-epdc.dtb           (originally this is "fdt_file=imx7d-sdb.dtb")      b.) setenv mmcargs 'setenv bootargs console=${console},${baudrate} root=${mmcroot} epdc video=mxcepdcfb:E060SCM,bpp=16'           (originally this is "mmcargs=setenv bootargs console=${console},${baudrate} root=${mmcroot}") 5. boot into Linux kernel, run unit-test: "/unit_tests/mxc_epdc_fb_test.out", should be able to have test patterns running on EPD.

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-345751 

This table shows how to configure i.MX51 EVK DIP Switches to boot from SD card and how to boot from internal ROM to use ATK: DS1 DS2 DS3 DS4 DS5 DS5 DS7 DS8 DS9 DS10 Boot from SD/MMC Card 0 0 0 0 0 0 1 1 0 0 Boot from i.ROM (ATK) 1 1 0 0 0 0 1 1 0 1

[中文翻译版] 见附件   原文链接： https://community.nxp.com/docs/DOC-344474