Just sharing some experiences during the development and studying.   Although, it appears some hardwares, it focuses on software to speed up your developing on your  hardware.     杂记共享一下在开发和学习过程中的经验。    虽然涉及一些硬件，但其本身关注软件，希望这些能加速您在自己硬件上的开发。   02/07/2024 i.MX8X security overview and AHAB deep dive i.MX8X security overview and AHAB deep dive - NXP Community   11/23/2023 “Standalone” Compile Device Tree https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/Standalone-Compile-Device-Tree/ta-p/1762373     10/26/2023 Linux Dynamic Debug https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/Linux-Dynamic-Debug/ta-p/1746611   08/10/2023 u-boot environment preset for sdcard mirror u-boot environment preset for sdcard mirror - NXP Community   06/06/2023 all(bootloader, device tree, Linux kernel, rootfs) in spi nor demo imx8qxpc0 mek all(bootloader, device tree, Linux kernel, rootfs)... - NXP Community     09/26/2022 parseIVT - a script to help i.MX6 Code Signing parseIVT - a script to help i.MX6 Code Signing - NXP Community   Provide  run under windows   09/16/2022   create sdcard mirror under windows create sdcard mirror under windows - NXP Community     08/03/2022   i.MX8MM SDCARD Secondary Boot Demo https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX8MM-SDCARD-Secondary-Boot-Demo/ta-p/1500011     02/16/2022 mx8_ddr_stress_test without UI   https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/mx8-ddr-stress-test-without-UI/ta-p/1414090   12/23/2021 i.MX8 i.MX8X Board Reset https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX8-i-MX8X-Board-Reset/ta-p/1391130       12/21/2021 regulator userspace-consumer https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/regulator-userspace-consumer/ta-p/1389948     11/24/2021 crypto af_alg blackkey demo crypto af_alg blackkey demo - NXP Community   09/28/2021 u-boot runtime modify Linux device tree(dtb) u-boot runtime modify Linux device tree(dtb) - NXP Community     08/17/2021 gpio-poweroff demo https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/gpio-poweroff-demo/ta-p/1324306         08/04/2021 How to use gpio-hog demo https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-to-use-gpio-hog-demo/ta-p/1317709       07/14/2021 SWUpdate OTA i.MX8MM EVK / i.MX8QXP MEK https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/SWUpdate-OTA-i-MX8MM-EVK-i-MX8QXP-MEK/ta-p/1307416     04/07/2021 i.MX8QXP eMMC Secondary Boot https://community.nxp.com/t5/i-MX-Community-Articles/i-MX8QXP-eMMC-Secondary-Boot/ba-p/1257704#M45       03/25/2021 sc_misc_board_ioctl to access the M4 partition from A core side sc_misc_board_ioctl to access the M4 partition fr... - NXP Community     03/17/2021 How to Changei.MX8X MEK+Base Board  Linux Debug UART https://community.nxp.com/t5/i-MX-Community-Articles/How-to-Change-i-MX8X-MEK-Base-Board-Linux-Debug-UART/ba-p/1246779#M43     03/16/2021 How to Change i.MX8MM evk Linux Debug UART https://community.nxp.com/t5/i-MX-Community-Articles/How-to-Change-i-MX8MM-evk-Linux-Debug-UART/ba-p/1243938#M40       05/06/2020 Linux fw_printenv fw_setenv to access U-Boot's environment variables Linux fw_printenv fw_setenv to access U-Boot's env... - NXP Community     03/30/2020 i.MX6 DDR calibration/stress for Mass Production https://community.nxp.com/docs/DOC-346065     03/25/2020 parseIVT - a script to help i.MX6 Code Signing https://community.nxp.com/docs/DOC-345998     02/17/2020 Start your machine learning journey from tensorflow playground Start your machine learning journey from tensorflow playground      01/15/2020 How to add  iMX8QXP PAD（GPIO) Wakeup How to add iMX8QXP PAD（GPIO) Wakeup    01/09/2020 Understand iMX8QX Hardware Partitioning By Making M4 Hello world Running Correctly https://community.nxp.com/docs/DOC-345359   09/29/2019 Docker On i.MX6UL With Ubuntu16.04 https://community.nxp.com/docs/DOC-344462   09/25/2019 Docker On i.MX8MM With Ubuntu https://community.nxp.com/docs/DOC-344473 Docker On i.MX8QXP With Ubuntu https://community.nxp.com/docs/DOC-344474     08/28/2019 eMMC5.0 vs eMMC5.1 https://community.nxp.com/docs/DOC-344265     05/24/2019 How to upgrade  Linux Kernel and dtb on eMMC without UUU How to upgrade Linux Kernel and dtb on eMMC without UUU     04/12/2019 eMMC RPMB Enhance and GP https://community.nxp.com/docs/DOC-343116   04/04/2019 How to Dump a GPT SDCard Mirror(Android O SDCard Mirror) https://community.nxp.com/docs/DOC-343079   04/04/2019 i.MX Create Android SDCard Mirror https://community.nxp.com/docs/DOC-343078   04/02/2019: i.MX Linux Binary_Demo Files Tips  https://community.nxp.com/docs/DOC-343075   04/02/2019:       Update Set fast boot        eMMC_RPMB_Enhance_and_GP.pdf   02/28/2019: imx_builder --- standalone build without Yocto https://community.nxp.com/docs/DOC-342702   08/10/2018: i.MX6SX M4 MPU Settings For RPMSG update    Update slide CMA Arrangement Consideration i.MX6SX_M4_MPU_Settings_For_RPMSG_08102018.pdf   07/26/2018 Understand ML With Simplest Code https://community.nxp.com/docs/DOC-341099     04/23/2018:     i.MX8M Standalone Build     i.MX8M Standalone Build.pdf     04/13/2018:      i.MX6SX M4 MPU Settings For RPMSG  update            Add slide CMA Arrangement  Consideration     i.MX6SX_M4_MPU_Settings_For_RPMSG_04132018.pdf   09/05/2017:       Update eMMC RPMB, Enhance  and GP       eMMC_RPMB_Enhance_and_GP.pdf 09/01/2017:       eMMC RPMB, Enhance  and GP       eMMC_RPMB_Enhance_and_GP.pdf 08/30/2017:     Dual LVDS for High Resolution Display(For i.MX6DQ/DLS)     Dual LVDS for High Resolution Display.pdf 08/27/2017:  L3.14.28 Ottbox Porting Notes:         L3.14.28_Ottbox_Porting_Notes-20150805-2.pdf MFGTool Uboot Share With the Normal Run One:        MFGTool_Uboot_share_with_NormalRun_sourceCode.pdf Mass Production with programmer        Mass_Production_with_NAND_programmer.pdf        Mass_Production_with_emmc_programmer.pdf AndroidSDCARDMirrorCreator https://community.nxp.com/docs/DOC-329596 L3.10.53 PianoPI Porting Note        L3.10.53_PianoPI_PortingNote_151102.pdf Audio Codec WM8960 Porting L3.10.53 PianoPI        AudioCodec_WM8960_Porting_L3.10.53_PianoPI_151012.pdf TouchScreen PianoPI Porting Note         TouchScreen_PianoPI_PortingNote_151103.pdf Accessing GPIO From UserSpace        Accessing_GPIO_From_UserSpace.pdf        https://community.nxp.com/docs/DOC-343344 FreeRTOS for i.MX6SX        FreeRTOS for i.MX6SX.pdf i.MX6SX M4 fastup        i.MX6SX M4 fastup.pdf i.MX6 SDCARD Secondary Boot Demo        i.MX6_SDCARD_Secondary_Boot_Demo.pdf i.MX6SX M4 MPU Settings For RPMSG        i.MX6SX_M4_MPU_Settings_For_RPMSG_10082016.pdf Security        Security03172017.pdf    NOT related to i.MX, only a short memo

Design Check Lists: HW Design Checking List for i.MX6DQSDL HW Design Checking List for i.Mx53 Hardware Design Checklist for i.MX28 HW_Design_Checking_List_for_i.MX6SoloX i.MX6UL Hardware design checklist   DDR Design Tool: I.MX53 DDR3 Script Aid imx53 DDR stress tester V0.042 i.Mx6DQSDL DDR3 Script Aid MX6DQP DDR3 Script Aid i.Mx6DQSDL LPDDR2 Script Aid i.Mx6SL LPDDR2 Script Aid i.MX6SX DDR3 Script Aid I.MX6UL DDR3 Script Aid i.MX6UL_LPDDR2_Script_Aid i.MX6ULL_DDR3_Script_Aid  i.MX6ULL_LPDDR2_Script_Aid  MX6SLL_LPDDR2_Script_Aid  MX6SLL_LPDDR3_Script_Aid  i.MX6 DDR Stress Test Tool V1.0.3 i.MX6/7 DDR Stress Test Tool V3.00 i.MX8MSCALE DDR Tool Release  i.MX8M DDR3L register programming aid  i.MX 8/8X Family DDR Tools Release   Application Notes: MX_Design_Validation_Guide I.MX6 series USB Certification Guides

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. i.MX 8M Family DDR Tools Overview The i.MX 8M Family DDR Tool is a Windows-based software to help users to do LPDDR4/DDR4/DDR3L training, stress test and DDR initial code generation for u-boot SPL. This page contains the latest releases for the i.MX 8M Family DDR Tools and cover the following SoCs : i.MX 8M Quad and its derivatives i.MX 8M Quadlite and i.MX 8M Dual i.MX 8M Mini Quad and its derivatives i.MX 8M Mini Quadlite/Dual/DualLite/Solo/SoloLite  i.MX 8M Nano Quad and its derivatives i.MX 8M Nano Quadlite/Dual/DualLite/Solo/SoloLite  i.MX 8M Plus   NOTE: For the i.MX 8/8X Family of DDR tools please refer to the: i.MX 8/8X Family DDR Tools Release   The purpose of the i.MX 8M Family DDR Tools is to enable users to generate and test a custom DRAM initialization based on their device configuration (density, number of chip selects, etc.) and board layout (data bus bit swizzling, etc.).  This process equips the user to then proceed with the bring-up of a boot loader and an OS.  Once the OS is brought up, it is recommended to run an OS-based memory test (like Linux memtester) to further verify and test the DDR memory interface.     The i.MX 8M Family DDR Tools consist of: DDR Register Programming Aid (RPA) MSCALE DDR Tool   For more details regarding these DDR tools and their usage, refer to the i.MX 8M DDR Tools User Guide.   i.MX 8M Family DDR Tool    The i.MX 8M Family DDR stress test tool is a Windows-based software tool that is used as a mechanism to verify that the DDR initialization is operational for use with u-boot and OS bring-up. To install the DDR Stress Test, save and extract the zip file mscale_ddr_tool_vXXX_setup.exe.zip   (where 'xxx' is the current version number) and follow the on-screen installation instructions.     i.MX 8M Family DDR Tool Requirements   The tool requires access to the Windows registry, hence users must run it in administrator mode. When users design new i.MX 8M Family boards, please make sure to follow the rules outlined in the respective Hardware Developers Guide and the MSCALE_DDR_Tool_User_Guide, which can help users bring up DDR devices on their respective i.MX 8M boards.   i.MX 8M Family DDR Tool User Guide   The i.MX 8M DDR tool includes the document: MSCALE_DDR_Tool_User_Guide NOTE: Please read the MSCALE_DDR_Tool_User_Guide inside the package carefully before you use this tool.   i.MX8M DDR Tool Revision History   Rev Major Changes* (Features) Comments 3.31 Integration of the workaround for 8MQ ERR051273   3.30 Fix DBI enabled issue for all i.MX 8M series Automatically identify ROHM and PCA9450 PMICs on i.MX 8M Nano board Fix 4GB/8GB memory tester issues   3.20 Add support to i.MX 8M Plus   3.10 Fixe UART communication issues for some specific characters between the PC software and the target board. Fine-tune DDRPHY registers in generated C code.   3.00 Add support to i.MX8M-nano Add support to different PMIC or PMIC configuration Add support to stress test for all DDR frequency points RPA tools for Nano include support for DDR3L, DDR4, and LPDDR4.   Note that the DDR3L and LPDDR4 RPAs contain the name preliminary only to denote that these RPAs are based on internal NXP validation boards where the DDR4 RPA is based on the released EVK.   2.10 Change DDR4 capacity computing method   2.00 Add support to i.MX8M-mini   * Further details available in the release notes   Sample configuration in the .ds script for i.MX 8M debug UART2: ################step 0: configure debug uart port. Assumes use of UART IO Pads.   ##### ##### If using non-UART pads (i.e. using other pads to mux out the UART signals), ##### ##### then it is up to the user to overwrite the following IO register settings   ##### memory set 0x3033023C 32 0x00000000 #IOMUXC_SW_MUX_UART2_RXD memory set 0x30330240 32 0x00000000 #IOMUXC_SW_MUX_UART2_TXD memory set 0x303304A4 32 0x0000000E #IOMUXC_SW_PAD_UART2_RXD memory set 0x303304A8 32 0x0000000E #IOMUXC_SW_PAD_UART2_TXD memory set 0x303304FC 32 0x00000000 #IOMUXC_SW_MUX_UART2_SEL_RXD sysparam set debug_uart   1 #UART index from 0 ('0' = UART1, '1' = UART2, '2' = UART3, '3' = UART4)   Sample configuration in the front of the .ds script for i.MX 8M debug UART3  ################step 0: configure debug uart port. Assumes use of UART IO Pads.   ##### ##### If using non-UART pads (i.e. using other pads to mux out the UART signals), ##### ##### then it is up to the user to overwrite the following IO register settings   ##### memory set 0x30330244 32 0x00000000 #IOMUXC_SW_MUX_UART3_RXD memory set 0x30330248 32 0x00000000 #IOMUXC_SW_MUX_UART3_TXD memory set 0x303304AC 32 0x0000000E #IOMUXC_SW_PAD_UART3_RXD memory set 0x303304B0 32 0x0000000E #IOMUXC_SW_PAD_UART3_TXD memory set 0x30330504 32 0x00000002 #IOMUXC_SW_MUX_UART3_SEL_RXD sysparam set debug_uart   2 #UART index from 0 ('0' = UART1, '1' = UART2, '2' = UART3, '3' = UART4)   Sample configuration in the front of the .ds script for i.MX 8M Mini PMIC configuration: ##############step 0.5: configure I2C port IO pads according to your PCB design.   ##### ########### You can modify the following instructions to adapt to your board PMIC ####### memory set 0x30330214 32 0x00000010  #IOMUXC_SW_MUX_I2C1_SCL memory set 0x30330218 32 0x00000010  #IOMUXC_SW_MUX_I2C1_SDA memory set 0x3033047C 32 0x000000C6 #IOMUXC_SW_PAD_I2C1_SCL memory set 0x30330480 32 0x000000C6  #IOMUXC_SW_PAD_I2C1_SDA sysparam set pmic_cfg 0x004B #bit[7:0] = PMIC addr,bit[15:8]=I2C Bus. Bus index from 0 ('0' = I2C1, '1' = I2C2, '2' = I2C3, '3' = I2C4) sysparam set pmic_set 0x2F01 #bit[7:0] = Reg val, bit[15:8]=Reg addr. #REG(0x2F) = 0x01 sysparam set pmic_set 0x0C02   #REG(0x0C) = 0x02 sysparam set pmic_set 0x171E   #REG(0x17) = 0x1E sysparam set pmic_set 0x0C00   #REG(0x0C) = 0x00 sysparam set pmic_set 0x2F11    #REG(0x2F)=0x11     i.MX 8M Family DDR Register Programming Aid (RPA) The i.MX 8M DDR RPA (or simply RPA) is an Excel spreadsheet tool used to develop DDR initialization for a user’s specific DDR configuration (DDR device type, density, etc.). The RPA generates the DDR initialization(in a separate Excel worksheet tab):   DDR Stress Test Script: This format is used specifically with the DDR stress test by first copying the contents in this worksheet tab and then pasting it to a text file, naming the document with the “.ds” file extension. The user will select this file when executing the DDR stress test. The How to Use Excel worksheet tab provides instructions on using the RPA   i.MX 8M Family DDR Register Programming Aid (RPA): Current Versions To obtain the latest RPAs, please refer to the following links (note, existing RPAs have been removed from this main page and moved to the SoC specific links below): i.MX 8M Quad : https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX8M-m850D-DDR-Register-Programming-Aid-RPA/ta-p/1172441 i.MX 8M Mini : https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX8MMini-m845S-DDR-Register-Programming-Aid-RPA/ta-p/1172443 i.MX 8M Nano: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX8MNano-m815S-DDR-Register-Programming-Aid-RPA/ta-p/1172444 i.MX 8M Plus: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-8MPlus-m865S-DDR-Register-Programming-Aids-RPA/ta-p/1235352   Processor Mask Revisions Memory Supported Latest RPA Version * i.MX 8M Quad & Derivatives All LPDDR4 Rev 33 i.MX 8M Quad & Derivatives All DDR4 Rev 18 i.MX 8M Quad & Derivatives All DDR3L Rev 9 i.MX 8M Mini & Derivatives A0 LPDDR4 Rev 22 i.MX 8M Mini & Derivatives A0 DDR4 Rev 21 i.MX 8M Mini & Derivatives A0 DDR3L Rev 10 i.MX 8M Nano & Derivatives A0 LPDDR4 Rev 9 i.MX 8M Nano & Derivatives A0 DDR4 Rev 12 i.MX 8M Nano & Derivatives A0 DDR3L Rev 6 i.MX 8M Plus & Derivatives A1 LPDDR4 Rev 9 i.MX 8M Plus & Derivatives A1 DDR4 Rev 9 * For the details about the updates, please refer to the Revision History tab of the respective RPA.    To modify the DRAM Frequency for a custom setting refer to iMX 8M Mini Register Programming Aid DRAM PLL setting    Related Resources Links: iMX 8M Mini Register Programming Aid DRAM PLL setting  i.MX 8/8X Series DDR Tool Release  i.MX 6/7 DDR Stress test GUI Tool i.MX 8M Application Processor Related Resources i.MX8M (m850D) DDR Register Programming Aid (RPA)  i.MX8MMini (m845S) DDR Register Programming Aid (RPA)  i.MX8MNano (m815S) DDR Register Programming Aid (RPA) i.MX 8MPlus (m865S) DDR Register Programming Aids (RPA)   i.MX 8ULP DDR tools: i.MX Software and Development Tools | NXP Semiconductors Scroll down to “Other Resources --> Tools --> DDR Tools”  

Application Note AN13872 - Enabling SWUpdate on i.MX 6ULL  is available on www.nxp.com    SWUpdate: Embedded Systems become more and more complex. Software for Embedded Systems have new features and fixes can be updated in a reliable way. Most of time, we need OTA(Over-The-Air) to upgrade the system. Like Android has its own update system. Linux also need an update system. SWUpdate project is thought to help to update an embedded system from a storage media or from network. However, it should be mainly considered as a framework, where further protocols or installers (in SWUpdate they are called handlers) can be easily added to the application. Mongoose daemon mode: Mongoose is a daemon mode of SWUpdate that provides a web server, web interface and web application. Mongoose is running on the target board(i.MX8MM EVK/i.MX8QXP MEK).Using Web browser to access it.   Suricatta daemon mode: Suricatta regularly polls a remote server for updates, downloads, and installs them. Thereafter, it reboots the system and reports the update status to the server. The screenshot is SWUpdate scuricatta working with hawkbit server.          

Symptoms   Trying to initialize a repo, for example:  $repo init -u https://github.com/nxp-imx/imx-manifest -b imx-linux-mickledore -m imx-6.1.36-2.1.0.xml we have the below log: File "/home/username/bin/repo", line 51 def print(self, *args, **kwargs): ^ SyntaxError: invalid syntax   Workaround (1)   The first workaround consist in change the python alternatives (caused when you have installed two or more python versions). NOTE: in my case, the python version that i want to change as first priority is python3.8 $sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.8 1   Then we run: $sudo update-alternatives --config python    To verify if your python priority was changed successfully try: $python --version   You should see the version configured as priority number 1.     Workaround (2)   The workaround is very simple, only we need modify the repo file $ nano ~/bin/repo   and we will change the python interpreter in the first line (from python to python3): ORIGINAL FILE   EDITED FILE   After to do this change, repo will works fine again.     I hope this can helps to you!   Best regards.

  Test environment   i.MX8MP EVK LVDS0 LVDS-HDMI  bridge(it6263) L5.15.5_1.0.0 Background   Some customers need show logo using LVDS panel. Current BSP doesn't support LVDS driver in Uboot. This patch provides i.MX8MPlus LVDS driver support in Uboot. If you want to connect it to LVDS panel , you need port your lvds panel driver like  simple-panel.c   Update [2022.9.19] Verify on L5.15.32_2.0.0  0001-L5.15.32-Add-i.MX8MP-LVDS-driver-in-uboot 'probe device is failed, ret -2, probe video device failed, ret -19' is caused by below code. It has been merged in attachment. // /* Only handle devices that have a valid ofnode */ // if (dev_has_ofnode(dev) && !(dev->driver->flags & DM_FLAG_IGNORE_DEFAULT_CLKS)) { // /* // * Process 'assigned-{clocks/clock-parents/clock-rates}' // * properties // */ // ret = clk_set_defaults(dev, CLK_DEFAULTS_PRE); // if (ret) // goto fail; // }   [2023.3.14] Verify on L5.15.71 0001-L5.15.71-Add-i.MX8MP-LVDS-support-in-uboot   [2023.9.12] For some panel with low DE, you need uncomment CTRL_INV_DE line and set this bit to 1. #include <linux/string.h> @@ -110,9 +111,8 @@ static void lcdifv3_set_mode(struct lcdifv3_priv *priv, writel(CTRL_INV_HS, (ulong)(priv->reg_base + LCDIFV3_CTRL_SET)); /* SEC MIPI DSI specific */ - writel(CTRL_INV_PXCK, (ulong)(priv->reg_base + LCDIFV3_CTRL_CLR)); - writel(CTRL_INV_DE, (ulong)(priv->reg_base + LCDIFV3_CTRL_CLR)); - + //writel(CTRL_INV_PXCK, (ulong)(priv->reg_base + LCDIFV3_CTRL_CLR)); + //writel(CTRL_INV_DE, (ulong)(priv->reg_base + LCDIFV3_CTRL_CLR)); }      

UPDATE: Note that this document describes eIQ Machine Learning Software for the NXP L4.14 BSP release. Beginning with the L4.19 BSP, eIQ Software is pre-integrated in the BSP release and this document is no longer necessary or being maintained. For more information on eIQ Software in these releases (L4.19, L5.4, etc), please refer to the "NXP eIQ Machine Learning" chapter in the Linux User Guide for that specific release.  Original Post: eIQ Machine Learning Software for iMX Linux 4.14.y kernel series is available now. The NXP eIQ™ Machine Learning Software Development Environment enables the use of ML algorithms on NXP MCUs, i.MX RT crossover processors, and i.MX family SoCs. eIQ software includes inference engines, neural network compilers, and optimized libraries and leverages open source technologies. eIQ is fully integrated into our MCUXpresso SDK and Yocto development environments, allowing you to develop complete system-level applications with ease. Source download, build and installation Please refer to document NXP eIQ(TM) Machine Learning Enablement (UM11226.pdf) for detailed instructions on how to download, build and install eIQ software on your platform. Sample applications To help get you started right away we've posted numerous howtos and sample applications right here in the community. Please refer to eIQ Sample Apps - Overview. Supported platforms eIQ Machine learning software for i.MX Linux 4.14.y supports the L4.14.78-1.0.0 and L4.14.98-2.0.0 GA releases running on i.MX 8 Series Applications Processors. For more information on artificial intelligence, machine learning and eIQ Software please visit AI & Machine Learning | NXP.

Hello everyone, this document will explain on how to use the UUU (Universal Update Utility) tool to flash Linux to an i.MX device (i.MX 8MM).   Requirements:   MX 8M Mini EVK UUU tool documentation, available here Linux Binary Demo Files - i.MX 8MMini EVK UUU 1.2.135 binary Serial console emulator (tera term or putty)   UUU auto script For this example is used the L4.14.98_2.0.0_ga demo image for the i.MX 8MM, inside the demo image we will find the auto script, which by default flash the eMMC of the board, the structure of the script is as following   /***********************************************************************************/ uuu_version 1.2.39   # This command will be run when i.MX6/7 i.MX8MM, i.MX8MQ SDP: boot -f imx-boot-imx8mmevk-sd.bin-flash_evk   # This command will be run when ROM support stream mode # i.MX8QXP, i.MX8QM SDPS: boot -f imx-boot-imx8mmevk-sd.bin-flash_evk   # These commands will be run when use SPL and will be skipped if no spl # SDPU will be deprecated. please use SDPV instead of SDPU # { SDPU: delay 1000 SDPU: write -f imx-boot-imx8mmevk-sd.bin-flash_evk -offset 0x57c00 SDPU: jump # }   # These commands will be run when use SPL and will be skipped if no spl # if (SPL support SDPV) # { SDPV: delay 1000 SDPV: write -f imx-boot-imx8mmevk-sd.bin-flash_evk -skipspl SDPV: jump # }   FB: ucmd setenv fastboot_dev mmc FB: ucmd setenv mmcdev ${emmc_dev} FB: ucmd mmc dev ${emmc_dev} FB: flash -raw2sparse all fsl-image-validation-imx-imx8mmevk.sdcard FB: flash bootloader imx-boot-imx8mmevk-sd.bin-flash_evk FB: ucmd if env exists emmc_ack; then ; else setenv emmc_ack 0; fi; FB: ucmd mmc partconf ${emmc_dev} ${emmc_ack} 1 0 FB: done /***********************************************************************************/    In short, when the board goes into serial downloader mode UUU downloads the bootloader to internal RAM, once done and uboot is running, through fastboot utility it will flash .sdcard file and uboot to the eMMC on the board.   More information about the protocol UUU use please refer to the UUU documentation (UUU.pdf) section 5 Supported protocol.   Running the tool In order to run the tool the binary of uuu needs to be downloaded, the binary files can be downloaded from the link above, uuu.exe is for Windows and uuu is for Linux. Once downloaded it can be placed inside the same file as the demo image, this so it is easy to run and cleaner on the shell commands.   Windows In windows OS the tool should be run using the Windows PowerShell in administrator mode, once open we will run the next commands: > .\uuu.exe uuu.auto   Linux >$ sudo ./uuu uuu.auto   The tool will start running and should be waiting for any i.MX device to be detected by host pc   Preparing the board For the board to be flashed it is needed to be in download mode, the switch configuration (i.MX 8MM EVK) is as following: SW1101  -  1010XXXXXX SW1102  -  XXXXXXXXX0   Connect a USB cable from the host pc which will run the tool to the USB OTG/TYPE C port, usually specified as download, on the board.   Connect a USB cable from the host to the OTG-to-UART for console output, usually specified as debug, on the board.   Open terminal emulator program with the following settings: Bits per second - 115200 Data bits - 8 Parity - None Stop bits - 1 Flow control - None   Power on the board, the download will start and the serial prompt will show the progress in uboot, wait until the tool show success.   Finally power off the board and change the switch configuration to boot from the eMMC, power on the board again and it should boot successfully!   Built in scripts One can use the built in scripts using the -b option to burn the bootloader  and the rootfs to the target flash, just type the command accordingly to the target flash device.    SD Write bootloader only: Windows: > .\uuu.exe -b sd <bootloader> Linux: $ sudo ./uuu -b sd <bootloader>   Replace <bootloader> for your .imx/.bin file, example using the i.MX 8MM for Windows and Linux respectively below. > .\uur.exe -b sd imx-boot-imx8mmevk-sd.bin-flash_evk $ sudo ./uuu -b sd imx-boot-imx8mmevk-sd.bin-flash_evk    Write whole Linux image Windows: > .\uuu.exe -b sd_all <bootloader> <rootfs>.sdcard Linux: $ sudo ./uuu -b sd_all <bootloader> <rootfs>.sdcard   Replace <bootloader> and <rootfs> for the name of your .imx/.bin and .sdcard files respectively, example using the i.MX 8MM below. > .\uuu.exe -b sd_all  imx-boot-imx8mmevk-sd.bin-flash_evk fsl-image-validation-imx-imx8mmevk.sdcard $ sudo ./uuu -b sd_all  imx-boot-imx8mmevk-sd.bin-flash_evk fsl-image-validation-imx-imx8mmevk.sdcard   eMMC Write bootloader only Windows: > .\uuu.exe -b emmc <bootloader> Linux: $ sudo ./uuu -b emmc <bootloader>   Example using i.MX 8MM > .\uuu.exe -b emmc imx-boot-imx8mmevk-sd.bin-flash_evk $ sudo ./uuu -b emmc imx-boot-imx8mmevk-sd.bin-flash_evk   Write whole Linux image Windows: > .\uuu.exe -b emmc_all <bootloader> <rootfs>.sdcard Linux: $ sudo ./uuu -b emmc_all <bootloader> <rootfs>.sdcard   Example using i.MX 8MM > .\uuu.exe -b emmc_all imx-boot-imx8mmevk-sd.bin-flash_evk fsl-image-validation-imx-imx8mmevk.sdcard $ sudo ./uuu -b emmc_all imx-boot-imx8mmevk-sd.bin-flash_evk fsl-image-validation-imx-imx8mmevk.sdcard   Hope this will helpful for everyone who is starting to use this flashing tool.

This document describes the i.MX 8MQ EVK HDMI output and mini-SAS connectors features on Linux and Android use cases, covering the supported daughter-board, the process to change Device Tree (DTS) files or Boot Images, and enable these different display options on the board.

NXP i.MX 8 series of application processors support running ArmV8a 64-bit and ArmV7a 32-bit user space programs.  A Hello World program that prints the size of a long int is cross-compiled as 32-bit and as 64-bit from an Ubuntu host and then each is copied to MCIMX8MQ-EVK and run. Resources: Ubuntu 18.04 LTS Host i.MX 8M Evaluation Kit|NXP  MCIMX8MQ-EVK Linux Binary Demo Files - i.MX 8MQuad EVK L4.9.88_2.0.0_GA release Source Code: Create a file with contents below using your favorite editor, example name hello-sizeInt.c. #include <stdio.h> int main (int argc, char **argv) { printf ("Hello World, size of long int: %zd\n", sizeof (long int)); return 0; }‍‍‍‍‍‍‍ Ubuntu host packages: $ sudo apt-get install -y gcc-arm-linux-gnueabihf $ sudo apt-get install -y gcc-aarch64-linux-gnu‍‍‍‍ Line 1 installs the ArmV7a cross-compile tools: arm-linux-gnueabihf-gcc is used to cross compile on Ubuntu host Line 2 install the ArmV8a cross-compile tools: aarch64-linux-gnu-gcc is used to cross compile on Ubuntu host Create Linux User Space Applications Build each application and use the static option to gcc to include run time libraries. Build ArmV7a 32-bit application: $ arm-linux-gnueabihf-gcc -static hello-sizeInt.c -o hello-armv7a‍-static‍‍ Build ArmV8a 64-bit application: $ aarch64-linux-gnu-gcc -static  hello-sizeInt.c -o hello-armv8a‍-static‍‍ Copy Hello applications from Ubuntu host and run on MCIMX8MQ-EVK Using a SDCARD written with images from L4.9.88_2.0.0 Linux release (see resources for image link), power on EVK with Ethernet connected to network and Serial Console port which was connected to a windows 10 PC. Launched a terminal client (TeraTerm) to access console port. Login credentials: root and no password needed. Since Ethernet was connected a DHCP IP address was acquired, 192.168.1.241 on the EVK.  On the Ubuntu host, secure copy the hello applications to EVK: $ scp hello-armv7a-static root@192.168.1.241:~/ hello-armv7a-static                           100%  389KB   4.0MB/s   00:00    $ scp hello-armv8a-static root@192.168.1.241:~/ hello-armv8a-static                           100%  605KB   4.7MB/s   00:00 ‍‍‍‍‍‍‍‍‍‍ Run: root@imx8mqevk:~# ./hello-armv8a-static Hello World, sizeof long int: 8 root@imx8mqevk:~# ./hello-armv7a-static Hello World, sizeof long int: 4‍‍‍‍‍‍‍‍

Here are some debug methods for kernel performance requirements or related issues. It includes all the common methods such as oops/panic issues, memory issues, and so on. Please check it in the attachments for details. OS and System analysis Oops/Panic case addr2line objdump gdb Pstore Kdump Memory debugging SLAB KASAN Kmemleak Performance Perf Ftrace eBPF/bcc

目录 1 i.MX8Mmini 板级开发包镜像结构 ............................... 2 2 创建 i.MX8Mmini Linux 4.14.78_ga 板级开发包编译环境 3 2.1 下载板级开发包 ...................................................... 3 2.2 创建yocto编译环境: ................................................ 4 2.3 编译sdk及安装 ........................................................ 7 2.4 独立编译 ................................................................. 8 3 DDR配置，测试与输出 ............................................ 13 4 i.MX8Mmini ATF ...................................................... 15 5 FSL Uboot SPL 定制 ............................................... 17 5.1 SPL的编译............................................................ 17 5.2 SPL的启动流程 .................................................... 26 5.3 SPL的定制............................................................ 33 6 FSL Uboot 定制 ....................................................... 39 6.1 FDT支持 ............................................................... 40 6.2 DM(driver model)支持 .......................................... 45 6.3 Uboot目录 结构 .................................................... 59 6.4 Uboot编译 ............................................................ 61 6.5 Uboot初始化流程 .................................................. 62 6.6 uboot 定制 ............................................................ 72 6.7 uboot debug信息 .................................................. 78

    Xenomai is real-time framework, which can run seamlessly side-by-side Linux as a co-kernel system, or natively over mainline Linux kernels (with or without PREEMPT-RT patch). The dual kernel nicknamed Cobalt, is a significant rework of the Xenomai 2.x system. Cobalt implements the RTDM specification for interfacing with real-time device drivers. The native linux version, an enhanced implementation of the experimental Xenomai/SOLO work, is called Mercury. In this environment, only a standalone implementation of the RTDM specification in a kernel module is required, for interfacing the RTDM-compliant device drivers with the native kernel. You can get more detailed information from Home · Wiki · xenomai / xenomai · GitLab       I have ported xenomai 3.1 to i.MX Yocto 4.19.35-1.1.0, and currently support ARM64 and test on i.MX8MQ EVK board. I did over night test( 5 real-time threads + GPU SDK test case) and stress test by tool stress-ng on i.MX8MQ EVK board. It looks lile pretty good. Current version (20200730) also support i.MX8MM EVK.     You need git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git, and git checkout xenomai-4.19.35-1.1.0-20200818 (which inlcudes all patches and bb file) and add the following variable in conf/local.conf before build xenomai by command bitbake xenomai.  XENOMAI_KERNEL_MODE = "cobalt"  PREFERRED_VERSION_linux-imx = "4.19-${XENOMAI_KERNEL_MODE}" IMAGE_INSTALL_append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" PREFERRED_VERSION_linux-imx = "4.19-${XENOMAI_KERNEL_MODE}" IMAGE_INSTALL_append += " xenomai" If XENOMAI_KERNEL_MODE = "cobalt", you can build dual kernel version. And If XENOMAI_KERNEL_MODE = "mercury", it is single kernel with PREEMPT-RT patch. The following is test result by the command (/usr/xenomai/demo/cyclictest -p 99 -t 5 -m -n -i 1000  -l 100000😞 //Over normal Linux kernel without GPU SDK test case T: 0 ( 4220) P:99 I:1000 C: 100000 Min: 7 Act: 10 Avg: 9 Max: 23 T: 1 ( 4221) P:99 I:1500 C: 66672 Min: 7 Act: 10 Avg: 10 Max: 20 T: 2 ( 4222) P:99 I:2000 C: 50001 Min: 7 Act: 12 Avg: 10 Max: 81 T: 3 ( 4223) P:99 I:2500 C: 39998 Min: 7 Act: 11 Avg: 10 Max: 29 T: 4 ( 4224) P:99 I:3000 C: 33330 Min: 7 Act: 13 Avg: 10 Max: 26 //Over normal Linux kernel with GPU SDK test case T: 0 ( 4177) P:99 I:1000 C: 100000 Min: 7 Act: 10 Avg: 11 Max: 51 T: 1 ( 4178) P:99 I:1500 C: 66673 Min: 7 Act: 12 Avg: 10 Max: 35 T: 2 ( 4179) P:99 I:2000 C: 50002 Min: 7 Act: 12 Avg: 11 Max: 38 T: 3 ( 4180) P:99 I:2500 C: 39999 Min: 7 Act: 12 Avg: 11 Max: 42 T: 4 ( 4181) P:99 I:3000 C: 33330 Min: 7 Act: 12 Avg: 11 Max: 36   //Cobalt with stress-ng --cpu 4 --io 2 --vm 1 --vm-bytes 512M --timeout 600s --metrics-brief T: 0 ( 4259) P:50 I:1000 C:3508590 Min:      0 Act:    0 Avg:    0 Max:      42 T: 1 ( 4260) P:50 I:1500 C:2338831 Min:      0 Act:    1 Avg:    0 Max:      36 T: 2 ( 4261) P:50 I:2000 C:1754123 Min:      0 Act:    1 Avg:    1 Max:      42 T: 3 ( 4262) P:50 I:2500 C:1403298 Min:      0 Act:    1 Avg:    1 Max:      45 T: 4 ( 4263) P:50 I:3000 C:1169415 Min:      0 Act:    1 Avg:    1 Max:      22   //Cobalt without GPU SDK test case T: 0 ( 4230) P:50 I:1000 C: 100000 Min: 0 Act: 0 Avg: 0 Max: 4 T: 1 ( 4231) P:50 I:1500 C:   66676 Min: 0 Act: 1 Avg: 0 Max: 4 T: 2 ( 4232) P:50 I:2000 C:   50007 Min: 0 Act: 1 Avg: 0 Max: 8 T: 3 ( 4233) P:50 I:2500 C:   40005 Min: 0 Act: 1 Avg: 0 Max: 3 T: 4 ( 4234) P:50 I:3000 C:   33338 Min: 0 Act: 1 Avg: 0 Max: 5 //Cobalt with GPU SDK test case T: 0 ( 4184) P:99 I:1000 C:37722968 Min: 0 Act: 1 Avg: 0 Max: 24 T: 1 ( 4185) P:99 I:1500 C:25148645 Min: 0 Act: 1 Avg: 0 Max: 33 T: 2 ( 4186) P:99 I:2000 C:18861483 Min: 0 Act: 1 Avg: 0 Max: 22 T: 3 ( 4187) P:99 I:2500 C:15089187 Min: 0 Act: 1 Avg: 0 Max: 23 T: 4 ( 4188) P:99 I:3000 C:12574322 Min: 0 Act: 1 Avg: 0 Max: 29 //Mercury without GPU SDK test case T: 0 ( 4287) P:99 I:1000 C:1000000 Min: 6 Act: 7 Avg: 7 Max: 20 T: 1 ( 4288) P:99 I:1500 C:  666667 Min: 6 Act: 9 Avg: 7 Max: 17 T: 2 ( 4289) P:99 I:2000 C:  499994 Min: 6 Act: 8 Avg: 7 Max: 24 T: 3 ( 4290) P:99 I:2500 C:  399991 Min: 6 Act: 9 Avg: 7 Max: 19 T: 4 ( 4291) P:99 I:3000 C:  333322 Min: 6 Act: 8 Avg: 7 Max: 21 //Mercury with GPU SDK test case T: 0 ( 4222) P:99 I:1000 C:1236790 Min: 6 Act: 7 Avg: 7 Max: 55 T: 1 ( 4223) P:99 I:1500 C:  824518 Min: 6 Act: 7 Avg: 7 Max: 44 T: 2 ( 4224) P:99 I:2000 C:  618382 Min: 6 Act: 8 Avg: 8 Max: 88 T: 3 ( 4225) P:99 I:2500 C:  494701 Min: 6 Act: 7 Avg: 8 Max: 49 T: 4 ( 4226) P:99 I:3000 C:  412247 Min: 6 Act: 7 Avg: 8 Max: 53 //////////////////////////////////////// Update for Yocto L5.4.47 2.2.0  /////////////////////////////////////////////////////////// New release for Yocto release L5.4.47 2.2.0 and it supports i.MX8M series (8MQ,8MM,8MN and 8MP). You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git,  and git checkout xenomai-5.4.47-2.2.0. You need to add the following variable in conf/local.conf before build xenomai by command bitbake imx-image-multimedia.  XENOMAI_KERNEL_MODE = "cobalt"  PREFERRED_VERSION_linux-imx = "5-${XENOMAI_KERNEL_MODE}" IMAGE_INSTALL_append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" PREFERRED_VERSION_linux-imx = "5-${XENOMAI_KERNEL_MODE}" IMAGE_INSTALL_append += " xenomai" //////////////////////////////////////// Update for Yocto L5.4.70 2.3.0  /////////////////////////////////////////////////////////// New release  for Yocto release L5.4.70 2.3.0 and it supports i.MX8M series (8MQ,8MM,8MN and 8MP) and i.MX8QM/QXP. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git and git checkout xenomai-5.4.70-2.3.0. Updating: 1, Support i.MX8QM and i.MX8QXP 2, Fix altency's the issue which uses legacy API to get time   //////////////////////////////////////// update for Yocto L5.4.70 2.3.2  /////////////////////////////////////////////////////////// New release for Yocto release L5.4.70 2.3.2. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git, and git checkout xenomai-5.4.70-2.3.2. Updating: 1, Enable Xenomai RTDM driver in Linux Kernel 2, Currently CAN, UART, GPIO,  SPI and Ethernet (in debug for RTNet)  are added in Xenomai. 3, Add KERNEL_DEVICETREE += " freescale/imx8mp-rt-evk.dtb " in sources/meta-imx/meta-bsp/conf/machine/imx8mpevk.conf to enable relative device in Xenomai domain, for example rt-imx8mp-flexcan.   //////////////////////////////////////// Update for Yocto L5.4.70 2.3.4  /////////////////////////////////////////////////////////// New release for Yocto release L5.4.70 2.3.4. You need to git clone  https://gitee.com/zxd2021-imx/xenomai-arm64.git and git checkout xenomai-5.4.70-2.3.4. Updating: 1, Enable RTNet FEC driver 2, Currently CAN, UART, GPIO,  SPI and Ethernet ( FEC Controller)  are added in Xenomai. 3, Add KERNEL_DEVICETREE += " freescale/imx8mp-rt-evk.dtb " in sources/meta-imx/meta-bsp/conf/machine/imx8mpevk.conf and KERNEL_DEVICETREE += " freescale/imx8mm-rt-ddr4-evk.dtb " in sources/meta-imx/meta-bsp/conf/machine/imx8mmddr4evk.conf to enable rt_fec device in Xenomai domain. Verifying the network connection by RTnet Ping Between i.MX8M Mini EVK and i.MX8M Plus EVK a, Setup test environment 1, Connect ENET1 of  i.MX8M Plus EVK (used as a master) and  ENET of i.MX8M Mini EVK (used as a slave) of  to a switch or hub 2, Modify /usr/xenomai/etc/rtnet.conf in i.MX8M Plus EVK board as the following: @@ -16,7 +16,7 @@ MODULE_EXT=".ko" # RT-NIC driver -RT_DRIVER="rt_eepro100" +RT_DRIVER="rt_fec" RT_DRIVER_OPTIONS="" # PCI addresses of RT-NICs to claim (format: 0000:00:00.0) @@ -30,8 +30,8 @@ REBIND_RT_NICS="" # The TDMA_CONFIG file overrides these parameters for masters and backup # masters. Leave blank if you do not use IP addresses or if this station is # intended to retrieve its IP from the master based on its MAC address. -IPADDR="10.0.0.1" -NETMASK="" +IPADDR="192.168.100.101" +NETMASK="255.255.255.0" # Start realtime loopback device ("yes" or "no") RT_LOOPBACK="yes" @@ -65,7 +65,7 @@ TDMA_MODE="master" # Master parameters # Simple setup: List of TDMA slaves -TDMA_SLAVES="10.0.0.2 10.0.0.3 10.0.0.4" +TDMA_SLAVES="192.168.100.102" # Simple setup: Cycle time in microsecond TDMA_CYCLE="5000" 3, Modify /usr/xenomai/etc/rtnet.conf in i.MX8M Mini EVK board as the following: @@ -16,7 +16,7 @@ MODULE_EXT=".ko" # RT-NIC driver -RT_DRIVER="rt_eepro100" +RT_DRIVER="rt_fec" RT_DRIVER_OPTIONS="" # PCI addresses of RT-NICs to claim (format: 0000:00:00.0) @@ -30,8 +30,8 @@ REBIND_RT_NICS="" # The TDMA_CONFIG file overrides these parameters for masters and backup # masters. Leave blank if you do not use IP addresses or if this station is # intended to retrieve its IP from the master based on its MAC address. -IPADDR="10.0.0.1" -NETMASK="" +IPADDR="192.168.100.102" +NETMASK="255.255.255.0" # Start realtime loopback device ("yes" or "no") RT_LOOPBACK="yes" @@ -59,13 +59,13 @@ STAGE_2_CMDS="" # TDMA mode of the station ("master" or "slave") # Start backup masters in slave mode, it will then be switched to master # mode automatically during startup. -TDMA_MODE="master" +TDMA_MODE="slave" # Master parameters # Simple setup: List of TDMA slaves -TDMA_SLAVES="10.0.0.2 10.0.0.3 10.0.0.4" +TDMA_SLAVES="192.168.100.102" # Simple setup: Cycle time in microsecond TDMA_CYCLE="5000" 4, rename imx8mm-rt-ddr4-evk.dtb to imx8mm-ddr4-evk.dtb in /run/media/mmcblk1p1,  rename imx8mp-rt-evk.dtb to imx8mp-evk.dtb in /run/media/mmcblk1p1, and reboot board. 5, Run the below command on i.MX8M Mini EVK board. cd /usr/xenomai/sbin/ ./rtnet start & 5, Run the below command on i.MX8M Plus EVK board. cd /usr/xenomai/sbin/ ./rtnet start & When you see the log (rt_fec_main 30be0000.ethernet (unnamed net_device) (uninitialized): Link is Up - 100Mbps/Full - flow control rx/tx) and you can run command "./rtroute" to check route table if the slave IP (192.168.100.102) is in route.. b, Verify the network connection using the command below: ./rtping -s 1024 192.168.100.102 //////////////////////////////////////// Update for Yocto L5.10.52 2.1.0  /////////////////////////////////////////////////////////// New release for Yocto release L5.10.52 2.1.0. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git and git checkout xenomai-5.10.52-2.1.0. Updating: 1, Upgrade Xenomai to v3.2 2, Enable Dovetail instead of ipipe. Copy xenomai-arm64 to <Yocto folder>/sources/meta-imx/meta-bsp/recipes-kernel, and add the following variable in conf/local.conf before build Image with xenomai enable by command bitbake imx-image-multimedia. XENOMAI_KERNEL_MODE = "cobalt" IMAGE_INSTALL_append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" IMAGE_INSTALL_append += " xenomai" Notice: If XENOMAI_KERNEL_MODE = "cobalt", you can build dual kernel version. And If XENOMAI_KERNEL_MODE = "mercury", it is single kernel with PREEMPT-RT patch.  Latency testing of Xenomai3.2+Dovetail with isolating CPU 2,3 ( Xenomai 3.2 on 8MM DDR4 EVK with GPU test case (GLES2/S08_EnvironmentMappingRefraction_Wayland) + iperf3 + 2 ping 65000 size + stress-ng --cpu 2 --io 2 --vm 1 --vm-bytes 256M --metrics-brief )😞 The following is test result by the command (/usr/xenomai/demo/cyclictest -a 2,3 -p 50 -t 5 -m -n -i 1000) root@imx8mmddr4evk:~# /usr/xenomai/demo/cyclictest -a 2,3 -p 50 -t 5 -m -n -i 1000 # /dev/cpu_dma_latency set to 0us policy: fifo: loadavg: 5.96 6.04 6.03 7/155 1349 T: 0 ( 615) P:50 I:1000 C:63448632 Min: 0 Act: 0 Avg: 0 Max: 55 T: 1 ( 616) P:50 I:1500 C:42299087 Min: 0 Act: 0 Avg: 1 Max: 43 T: 2 ( 617) P:50 I:2000 C:31724315 Min: 0 Act: 0 Avg: 1 Max: 51 T: 3 ( 618) P:50 I:2500 C:25379452 Min: 0 Act: 0 Avg: 1 Max: 53 T: 4 ( 619) P:50 I:3000 C:21149543 Min: 0 Act: 0 Avg: 1 Max: 47 //////////////////////////////////////// Update for Yocto L5.10.72 2.2.2  /////////////////////////////////////////////////////////// New release for Yocto release L5.10.72 2.2.2. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git and git checkout xenomai-5.10.72-2.2.2. Updating: 1, Upgrade Xenomai to v3.2.1 Copy xenomai-arm64 to <Yocto folder>/sources/meta-imx/meta-bsp/recipes-kernel, and add the following variable in conf/local.conf before build Image with xenomai enable by command bitbake imx-image-multimedia. XENOMAI_KERNEL_MODE = "cobalt" IMAGE_INSTALL_append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" IMAGE_INSTALL_append += " xenomai" //////////////////////////////////////// Update for Yocto L5.15.71 2.2.0  /////////////////////////////////////////////////////////// New release for Yocto release L5.15.71 2.2.0. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git and git checkout xenomai-5.15.71-2.2.0. Updating: 1, Upgrade Xenomai to v3.2.2 Copy xenomai-arm64 to <Yocto folder>/sources/meta-imx/meta-bsp/recipes-kernel, and add the following variable in conf/local.conf before build Image with xenomai enable by command bitbake imx-image-multimedia. XENOMAI_KERNEL_MODE = "cobalt" IMAGE_INSTALL:append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" IMAGE_INSTALL:append += " xenomai"   //////////////////////////////////////// Update for Yocto L6.1.55 2.2.0  /////////////////////////////////////////////////////////// New release for Yocto release L6.1.55 2.2.0. You need to git clone https://gitee.com/zxd2021-imx/xenomai-arm64.git recipes-rtlinux-xenomai -b Linux-6.1.x Updating: 1, Upgrade Xenomai to v3.2.4 and support i.MX93 2, Enable EVL (aka Xenomai 4) for i.MX93 and legacy i.MX(6/7D/8X/8M) Copy recipes-rtlinux-xenomai to <Yocto folder>/sources/meta-imx/meta-bsp/, and add the following variable in conf/local.conf before build Image with xenomai enable by command bitbake imx-image-multimedia. XENOMAI_KERNEL_MODE = "cobalt" IMAGE_INSTALL:append += " xenomai" or XENOMAI_KERNEL_MODE = "mercury" IMAGE_INSTALL:append += " xenomai" or XENOMAI_KERNEL_MODE = "evl" IMAGE_INSTALL:append += " libevl"  

This guide is about how to use EVIS to create user nodes and kernels in OpenVX to implement image processing on NPU(i.MX8MP)/GPU(i.MX8QM). Take gaussian filter as an example. It is tested on i.MX8QM and i.MX8MP. User Node Creation from User Kernel 1. Define a user node Register a user kernel by its ID or name For example, #define VX_KERNEL_NAME_GAUSSIAN "com.nxp.extension.gaussian" #define VX_KERNEL_ENUM_GAUSSIAN 100 Get the kernel reference by the ID or name For example, vx_kernel kernel = vxGetKernelByName(context, VX_KERNEL_NAME_GAUSSIAN); vx_kernel kernel = vxGetKernelByEnum(context, VX_KERNEL_ENUM_GAUSSIAN ); Create a user node vx_node node = vxCreateGenericNode(graph, kernel); Set input/output node parameters For example, vx_status status = vxSetParameterByIndex(node, index++, (vx_reference)in_image); status |= vxSetParameterByIndex(node, index++, (vx_reference)out_image); 2. Create InputValidator/OutputValidator functions for the node The validators are only used for graph verification. For example, static vx_status VX_CALLBACK vxGaussianInputValidator(vx_node node, vx_uint32 index) static vx_status VX_CALLBACK vxGaussianOutputValidator(vx_node node, vx_uint32 index, vx_meta_format metaObj) ToDo: a. InputValidator: Get the reference to the parameter object   vx_parameter paramObj = NULL; vx_image imgObj = NULL; paramObj=vxGetParameterByIndex(node, index); vxQueryParameter(paramObj, VX_PARAMETER_REF, &imgObj, sizeof(vx_image)); Check meta-data restriction vxQueryImage(imgObj, VX_IMAGE_FORMAT, &imgFmt, sizeof(imgFmt)); Check consistency with other parameters if (VX_DF_IMAGE_U8==imgFmt) status = VX_SUCCESS; else status = VX_ERROR_INVALID_VALUE; b. OutputValidator Set the meta_format object with expected meta-data for the output status |= vxSetMetaFormatAttribute(metaObj, VX_IMAGE_FORMAT, &imgFmt, sizeof(imgFmt)); status |= vxSetMetaFormatAttribute(metaObj, VX_IMAGE_WIDTH, &width, sizeof(width)); status |= vxSetMetaFormatAttribute(metaObj, VX_IMAGE_HEIGHT, &height, sizeof(height)); 3. Create Initializer function for the node. The initializer is used to specify workdim, global work size and local work size for the user kernel. These parameters are similiar to that in OpenCL. For example,                                                                                    /* workdim, globel offset, globel scale, local size, globel size */ vx_kernel_execution_parameters_t shaderParam = {2,               {0, 0, 0},        {0, 0, 0},        {0, 0, 0},   {0, 0, 0}}; vx_status VX_CALLBACK vxGaussianInitializer(vx_node nodObj, const vx_reference *paramObj, vx_uint32 paraNum) Set attribute to the node vxSetNodeAttribute(nodObj, VX_NODE_ATTRIBUTE_KERNEL_EXECUTION_PARAMETERS, &shaderParam, sizeof(vx_kernel_execution_parameters_t)); Note: The links below are guides about OpenCL on GPU, which are helpful to understand OpenVX implemented on GPU/NPU. OpenCL Work Item Ids: Global/Group/Local OpenCL Programming Guide OpenCL Resources Introduction to OpenCL 4. Create Deinitializer function for the node (Optional) It is used to de-allocate memory allocated at initializer. User Kernel on NPU/GPU Creation 1. Create description of a user kernel For example, vx_kernel_description_t vxGaussianKernelVXCInfo = { VX_KERNEL_ENUM_GAUSSIAN, VX_KERNEL_NAME_GAUSSIAN, nullptr, vxGaussianKernelParam, (sizeof(vxGaussianKernelParam)/sizeof(vxGaussianKernelParam[0])), vxGaussianValidator, nullptr, nullptr, vxGaussianInitializer, nullptr }; 2. Register the new kernel For example, static vx_kernel_description_t* kernels[] = { &vxGaussianKernelVXCInfo, }; 3. Write kernel source implemented on NPU/GPU For example, char vxcKernelSource[] = { "#include \ \n\ \n\ \n\ __kernel void gaussian\n\ ( \n\ __read_only image2d_t in_image, \n\ __write_only image2d_t out_image \n\ ) \n\ { \n\ int2 coord = (int2)(get_global_id(0), get_global_id(1)); \n\ int2 coord_out = coord; \n\ vxc_uchar16 lineA, lineB, lineC, out;\n\ int2 coord_in1 = coord + (int2)(-1, -1);\n\ VXC_OP4(img_load, lineA, in_image, coord_in1, 0, VXC_MODIFIER(0, 15, 0, VXC_RM_TowardZero, 0));\n\ int2 coord_in2 = coord + (int2)(-1, 0);\n\ VXC_OP4(img_load, lineB, in_image, coord_in2, 0, VXC_MODIFIER(0, 15, 0, VXC_RM_TowardZero, 0));\n\ int2 coord_in3 = coord + (int2)(-1, 1);\n\ VXC_OP4(img_load, lineC, in_image, coord_in3, 0, VXC_MODIFIER(0, 15, 0, VXC_RM_TowardZero, 0));\n\ int info = VXC_MODIFIER_FILTER(0, 13, 0, VXC_FM_Guassian, 0);\n\ VXC_OP4(filter, out, lineA, lineB, lineC, info); ;\n\ VXC_OP4_NoDest(img_store, out_image, coord_out, out, VXC_MODIFIER(0, 13, 0, VXC_RM_TowardZero, 0)); \n\ }\n\ " }; Note: the source is written by EVIS instructions with less latency. But the EVIS instructions are limited. These fucntions defination can be found in "cl_viv_vx_ext.h" located at "/usr/include/CL/cl_viv_vx_ext.h". Read back the processed data by GPU/NPU to check if the operations are correct. For example, status = vxCopyImagePatch(vx_out_image, &rect, 0, &addressing, data2, VX_READ_ONLY, VX_MEMORY_TYPE_HOST); 4. Build the NPU/GPU source code runtime For example, programObj = vxCreateProgramWithSource(ContextVX, 1, programSrc, &programLen); vxBuildProgram(programObj, "-cl-viv-vx-extension"); 5. Add kernel to the program For example, ... kernelObj = vxAddKernelInProgram(programObj, kernels[i]->name, kernels[i]->enumeration, kernels[i]->numParams, kernels[i]->validate, kernels[i]->initialize, kernels[i]->deinitialize ); ... for(vx_uint32 j=0; j < kernels[i]->numParams; j++) { status = vxAddParameterToKernel(kernelObj, j, kernels[i]->parameters[j].direction, kernels[i]->parameters[j].data_type, kernels[i]->parameters[j].state ); 6. Finalize the kernel creation For example, status = vxFinalizeKernel(kernelObj); Exercise The example is attached. You can build and test it on i.MX8QM or i.MX8MP. Results on i.MX8QM: References: Khronosdotorg/resources.md at master · KhronosGroup/Khronosdotorg · GitHub  Further Reading: OpenVX Vision Image Extension API Introduction - Basic API OpenVX Vision Image Extension API Introduction - DP Dot Products

This document is a user guide for the GStreamer version 1.0 based accelerated solution included in all the i.MX 8 family SoCs supported by NXP BSP L5.4.24_1.1.0. Some instructions assume a host machine running a Linux distribution, such as Ubuntu, connected to i.MX 8 device. These commands were tested using Ubuntu 18.04 LTD, and while Ubuntu is not required on the host machine, other distributions have not been tested. These instructions are targeted for use with the following hardware: • i.MX 8MQ EVK • i.MX 8MN EVK • i.MX 8MN EVK • i.MX 8QXP MEK B0 • i.MX 8QM MEK B0   Release History v1.0 - Mar 2020 - Initial release. v2.0 - Sep 2020: Added the following content: - Mux/Demux Examples - Audio Examples - Image Examples - Transcode Examples - Streaming Examples - Multi-Display Examples - Scaling and Rotation Examples - Zero-copy Examples - Debug Examples Maintainers: . Marco Franchi . Pedro Jardim

1.Test environment Board: i.MX8MPlus, RM67199 BSP: uboot 2022.04, linux-6.1.1-1.0.1 2.Modification of uboot  In uboot, you need comment the video_link_shut_down and dm_remove_devices_flags in announce_and_cleanup function. #if defined(CONFIG_VIDEO_LINK) //video_link_shut_down(); #endif board_quiesce_devices(); printf("\nStarting kernel ...%s\n\n", fake ? "(fake run for tracing)" : ""); /* * Call remove function of all devices with a removal flag set. * This may be useful for last-stage operations, like cancelling * of DMA operation or releasing device internal buffers. */ // #ifndef CONFIG_POWER_DOMAIN // dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL | DM_REMOVE_NON_VITAL); // /* Remove all active vital devices next */ // dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL); // #endif cleanup_before_linux(); }  After doing this, the uboot logo will not be cleaned before Linux PM framework. 3.Modification of Linux You need add  CONFIG_LOGO=n into defconfig file to disable kernel logo.  3.1 Disable the power down of mediamix and mipi-dphy in gpcv2.c Please add below code into the beginning of  imx_pgc_power_down function if ((strcmp(genpd->name, "mipi-phy1") == 0) || (strcmp(genpd->name, "mediamix") == 0)) { return 0; }  3.2 Only reset lcdif in the last call of drm framework Please modify imx_lcdifv3_runtime_resume function like this. The imx_lcdifv3_runtime_resume function will be called two times, thus the lcdif will be reset two times.We can let it only reset last time,which before the rootfs mount. bool rst = false; ////////////////////////////// static int imx_lcdifv3_runtime_resume(struct device *dev) { int ret = 0; struct lcdifv3_soc *lcdifv3 = dev_get_drvdata(dev); if (unlikely(!atomic_read(&lcdifv3->rpm_suspended))) { dev_warn(lcdifv3->dev, "Unbalanced %s!\n", __func__); return 0; } if (!atomic_dec_and_test(&lcdifv3->rpm_suspended)) return 0; /* set LCDIF QoS and cache */ if (of_device_is_compatible(dev->of_node, "fsl,imx93-lcdif")) regmap_write(lcdifv3->gpr, 0xc, 0x3712); request_bus_freq(BUS_FREQ_HIGH); ret = lcdifv3_enable_clocks(lcdifv3); if (ret) { release_bus_freq(BUS_FREQ_HIGH); return ret; } ////////////////////////////// if (rst) { /* clear sw_reset */ writel(CTRL_SW_RESET, lcdifv3->base + LCDIFV3_CTRL_CLR); rst = false; } rst = true; ////////////////////////////// /* enable plane FIFO panic */ lcdifv3_enable_plane_panic(lcdifv3); return ret; } 4.Conclusion The uboot logo will be cleaned at log "imx-drm 1.0.0 20120507 for display-subsystem on minor 1". The boot time of  systemd service on evk is very long. For weston.service, it needs 3 seconds. From log here we test, the pcie and ethernet probe after drm system also cost about 1 second. If you want to reduce the boot time of other modules, you can try to reduce the system service and disable pcie/ethernet drivers if you don't need them. [ 2.505616] [drm] Initialized imx-drm 1.0.0 20120507 for display-subsystem on minor 1 [ 2.620324] imx6q-pcie 33800000.pcie: iATU unroll: enabled [ 2.620335] imx6q-pcie 33800000.pcie: iATU regions: 4 ob, 4 ib, align 64K, limit 16G [ 2.720689] imx6q-pcie 33800000.pcie: PCIe Gen.1 x1 link up [ 2.820996] imx6q-pcie 33800000.pcie: PCIe Gen.2 x1 link up [ 2.821003] imx6q-pcie 33800000.pcie: Link up, Gen2 [ 2.821010] imx6q-pcie 33800000.pcie: PCIe Gen.2 x1 link up [ 2.821112] imx6q-pcie 33800000.pcie: PCI host bridge to bus 0000:00 [ 2.821119] pci_bus 0000:00: root bus resource [bus 00-ff] [ 2.821126] pci_bus 0000:00: root bus resource [io 0x0000-0xffff] [ 2.821133] pci_bus 0000:00: root bus resource [mem 0x18000000-0x1fefffff] [ 2.821161] pci 0000:00:00.0: [16c3:abcd] type 01 class 0x060400 [ 2.821176] pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x000fffff] [ 2.821187] pci 0000:00:00.0: reg 0x38: [mem 0x00000000-0x0000ffff pref] [ 2.821232] pci 0000:00:00.0: supports D1 [ 2.821237] pci 0000:00:00.0: PME# supported from D0 D1 D3hot D3cold [ 2.824664] pci 0000:01:00.0: [1b4b:2b42] type 00 class 0x020000 [ 2.824725] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x000fffff 64bit pref] [ 2.824761] pci 0000:01:00.0: reg 0x18: [mem 0x00000000-0x000fffff 64bit pref] [ 2.825066] pci 0000:01:00.0: supports D1 D2 [ 2.825072] pci 0000:01:00.0: PME# supported from D0 D1 D3hot D3cold [ 2.835499] pci 0000:00:00.0: BAR 0: assigned [mem 0x18000000-0x180fffff] [ 2.835511] pci 0000:00:00.0: BAR 15: assigned [mem 0x18100000-0x182fffff pref] [ 2.835519] pci 0000:00:00.0: BAR 6: assigned [mem 0x18300000-0x1830ffff pref] [ 2.835530] pci 0000:01:00.0: BAR 0: assigned [mem 0x18100000-0x181fffff 64bit pref] [ 2.835561] pci 0000:01:00.0: BAR 2: assigned [mem 0x18200000-0x182fffff 64bit pref] [ 2.835590] pci 0000:00:00.0: PCI bridge to [bus 01-ff] [ 2.835598] pci 0000:00:00.0: bridge window [mem 0x18100000-0x182fffff pref] [ 2.835899] pcieport 0000:00:00.0: PME: Signaling with IRQ 218 [ 2.897767] Console: switching to colour frame buffer device 135x120 [ 3.098361] imx-drm display-subsystem: [drm] fb0: imx-drmdrmfb frame buffer device [ 3.111239] pps pps0: new PPS source ptp0 [ 3.316650] fec 30be0000.ethernet eth0: registered PHC device 0 [ 3.323645] imx-dwmac 30bf0000.ethernet: IRQ eth_lpi not found [ 3.329593] imx-dwmac 30bf0000.ethernet: force_sf_dma_mode is ignored if force_thresh_dma_mode is set. [ 3.340074] imx-dwmac 30bf0000.ethernet: User ID: 0x10, Synopsys ID: 0x51 [ 3.346883] imx-dwmac 30bf0000.ethernet: DWMAC4/5 [ 3.351684] imx-dwmac 30bf0000.ethernet: DMA HW capability register supported [ 3.358825] imx-dwmac 30bf0000.ethernet: RX Checksum Offload Engine supported [ 3.365966] imx-dwmac 30bf0000.ethernet: Wake-Up On Lan supported [ 3.372113] imx-dwmac 30bf0000.ethernet: Enable RX Mitigation via HW Watchdog Timer [ 3.379778] imx-dwmac 30bf0000.ethernet: Enabled L3L4 Flow TC (entries=8) [ 3.386573] imx-dwmac 30bf0000.ethernet: Enabled RFS Flow TC (entries=10) [ 3.393373] imx-dwmac 30bf0000.ethernet: Enabling HW TC (entries=256, max_off=256) [ 3.400950] imx-dwmac 30bf0000.ethernet: Using 34 bits DMA width [ 3.608045] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller [ 3.613580] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 1 [ 3.621621] xhci-hcd xhci-hcd.1.auto: hcc params 0x0220fe6d hci version 0x110 quirks 0x0000002001010010 [ 3.631059] xhci-hcd xhci-hcd.1.auto: irq 226, io mem 0x38200000 [ 3.637197] xhci-hcd xhci-hcd.1.auto: xHCI Host Controller [ 3.642698] xhci-hcd xhci-hcd.1.auto: new USB bus registered, assigned bus number 2 [ 3.650365] xhci-hcd xhci-hcd.1.auto: Host supports USB 3.0 SuperSpeed [ 3.657695] hub 1-0:1.0: USB hub found [ 3.661473] hub 1-0:1.0: 1 port detected [ 3.665669] usb usb2: We don't know the algorithms for LPM for this host, disabling LPM. [ 3.674445] hub 2-0:1.0: USB hub found [ 3.678220] hub 2-0:1.0: 1 port detected [ 3.683428] imx-cpufreq-dt imx-cpufreq-dt: cpu speed grade 7 mkt segment 2 supported-hw 0x80 0x4 [ 3.693184] Hot alarm is canceled. GPU3D clock will return to 64/64 [ 3.702683] sdhci-esdhc-imx 30b50000.mmc: Got CD GPIO [ 3.703346] mxc-mipi-csi2-sam 32e40000.csi: supply mipi-phy not found, using dummy regulator [ 3.716645] : mipi_csis_imx8mp_phy_reset, No remote pad found! [ 3.722602] mxc-mipi-csi2-sam 32e40000.csi: lanes: 2, hs_settle: 13, clk_settle: 2, wclk: 1, freq: 500000000 [ 3.739353] mmc1: SDHCI controller on 30b50000.mmc [30b50000.mmc] using ADMA [ 3.752018] isi-m2m 32e00000.isi:m2m_device: Register m2m success for ISI.0 [ 3.759172] cfg80211: Loading compiled-in X.509 certificates for regulatory database [ 3.768303] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7' [ 3.787598] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2 [ 3.795171] ALSA device list: [ 3.796227] platform regulatory.0: Falling back to sysfs fallback for: regulatory.db [ 3.799186] No soundcards found. [ 3.819630] EXT4-fs (mmcblk2p2): mounted filesystem with ordered data mode. Quota mode: none. [ 3.828212] VFS: Mounted root (ext4 filesystem) on device 179:2. [ 3.834944] devtmpfs: mounted

Hello, here Jorge. On this post I will explain how to configure, record and play audio using an i.MX 8MIC-RPI-MX8 Board. Requirements: I.MX 8M Mini EVK Linux Binary Demo Files - i.MX 8MMini EVK (L5.15.52_2.1.0) i.MX 8MIC-RPI-MX8 Board Serial console emulator (Tera Term, Putty, etc.) Headphones/speakers The 8MIC-RPI-MX8 accessory board is designed for voice enabled application prototyping and development on the i.MX 8M family. The board plugs directly into the 40-pin expansion connector on the i.MX 8M Mini and Nano EVK’s. Some features about this board are: 8 PDM Microphones 8 monochrome LEDs 4 multi-color LEDs 2 status LEDs 4 pushbuttons Microphone Mute Switch Microphone geometry switch Connecting the i.MX 8MIC-RPI-MX8 Board. The i.MX 8MIC-RPI-MX8 Board has a 40-pin expansion connector that you can plug it directly to the EVK board. Ensure that pin 1 of the 8MIC-RPI-MX8 is aligned with pin 1 on the EVK J1001 as is showed on the next figure:  Selecting the device tree on the board. Once the pre-compiled image is flashed on the board (Flashing Linux BSP using UUU) and you connected the 8MIC-RPI-MX8 it is necessary to select the correct device tree to handle 8MIC board. On U-boot check the available .dtb files on the BSP using the next command: u-boot=> fatls mmc 2:1 And you will get the corresponding list of .dbt files:  On this case we are working with an I.MX 8M Mini EVK and the corresponding .dtb file is: imx8mm-evk-8mic-revE.dtb To select it you need to set the environment variable and save it with: u-boot=> setenv fdtfile imx8mm-evk-8mic-revE.dtb u-boot=> saveenv Doble check it using: u-boot=> printenv fdtfile   Now it is time to boot Linux using the next command: u-boot=> boot Recording audio with the i.MX 8MIC-RPI-MX8 Board. The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI functionality to the Linux operating system. ALSA has the following significant features: Efficient support for all types of audio interfaces, from consumer sound cards to professional multichannel audio interfaces. Fully modularized sound drivers. SMP and thread-safe design. User space library (alsa-lib) to simplify application programming and provide higher level functionality. Support for the older Open Sound System (OSS) API, providing binary compatibility for most OSS programs. Once we are on Linux, we can check our audio codecs detected on the board using: arecord -l   Now, to record audio we need to use the ALSA arecord command to start recording with IMX8 boards, there are different options that you can check on the next link. On this case we are going to use the next: arecord -D hw:imxaudiomicfil -c8 -f s16_le -r48000 -d10 sample.wav -D: selects the device. -c: selects the number of channels on the recording. -f: selects the format. -r: selects the sample rate. -d: determinate the duration recording time in seconds. sample.wav: Is the name of the resulting audio file. Running the last command, we started to record audio. It is time to make some noise and record it!   Playing audio from IMX8 boards. Now it is time to connect our headphones or speakers to the jack.   Also, as on arecord command you can check the devices where you can play audio from the board using the next command: aplay -l And you will get all the codecs to play audio:   To play our recordings we need to use the ALSA aplay command, it is important to select the correct audio codec to hear the audio from the jack on the board: aplay -Dplughw:3,0 sample.wav -D: selects the device. sample.wav: Is the name of audio file to play   Hope this will helpful for people who wants to record audio using PDM microphones and playing audio from IMX8 boards. Best regards.

Tips collected from zhaoyang-b49593 and dandouglass-b41520 while enabling redundant boot: Using i.MX 8MQ, same method can be applied for other i.MX devices that support redundant boot, see SoC Reference Manual. As described on the RM, if primary image authentication fails the ROM can reset and try booting a secondary image. This feature is only available on closed mode with properly signed binaries, otherwise the ROM boots the primary image despite the auth failure. For the i.MX 8MQ, the secondary image must start with spl, not HDMI firmware. Note, there is no ROM redundancy for the hdmi fw, if it is corrupt user can store a 2nd copy on a different memory address and update at run time. Steps to generate a dual spl image: 1. Build and Sign bootable binary (spl, u-boot, atf, fw, etc) Use the Yocto BSP or follow this post to build outside the Yocto environment. To sign the binary, follow the documentation on u-boot source: <u-boot>/doc/imx/habv4/guides/mx8m_secure_boot.txt Program image to the SD card: dd if=signed_flash.bin of=<sd path> bs=1024 seek=33 After boot you can use "hab_status" to verify that no events were generated: u-boot=> hab_status Secure boot disabled HAB Configuration: 0xf0, HAB State: 0x66 2. Corrupt spl on your boot image You can corrupt anywhere on the spl signed area. For easier visualization at boot time we can corrupt the SPL banner. First create a copy: cp signed_flash.bin signed_flash_corrupt.bin Find the banner: hexdump -C signed_flash.bin | grep 2019 00020190 26 1c 40 92 04 00 80 d2 05 01 80 52 c4 20 04 aa |&.@........R. ..| 0002eac0 32 30 31 39 2e 30 34 2d 30 30 30 32 39 2d 67 34 |2019.04-00029-g4| 000dde10 3a 20 20 00 55 2d 42 6f 6f 74 20 32 30 31 39 2e |: .U-Boot 2019.| 0002eac3 is on spl area, where "9" for 2019 is, replace by "X" printf "X" > X dd if=X of=signed_flash_corrupt.bin seek=$((0x2eac3)) bs=1 conv=notrunc Verify corrupt binary hexdump -C -s 0x2eac0 -n 64 signed_flash_corrupt.bin 0002eac0 32 30 31 58 2e 30 34 2d 30 30 30 32 39 2d 67 34 |201X.04-00029-g4| 0002ead0 37 63 31 39 32 32 20 28 41 70 72 20 32 37 20 32 |7c1922 (Apr 27 2| Transfer image to SD Card dd if=signed_flash_corrupt.bin of=<sd path> bs=1024 seek=33 Now, you should see hab events after running "hab_status" on u-boot 3. Create a secondary boot image This can be the same content as your primary image without the HDMI fw or it can be a different spl image. For easier visualization, we can change the SPL banner, on the code this time. Modify banner at ./common/spl/spl.c as: - puts("\nU-Boot " SPL_TPL_NAME " " PLAIN_VERSION " (" U_BOOT_DATE " - " + puts("\nSecondary U-Boot " SPL_TPL_NAME " " PLAIN_VERSION " (" U_BOOT_DATE " - " As mentioned above, we want our boot image without the HDMI fw, when running imx-mkimage use the flash_evk_no_hdmi target: make SOC=iMX8MQ flash_evk_no_hdmi Sign the image as in step 1. If you program the new image to the SD you should see the new banner. Make sure to run hab_status to confirm that no HAB events are generated. 4. Program SRK Hash and Close SoC Follow the documentation on u-boot source for SRK programming and closing the device: <u-boot>/doc/imx/habv4/guides/mx8m_secure_boot.txt Before closing the SoC, but after the SRK is programmed, try your images to confirm no HAB events are generated. Be careful with this step, errors could brick your board. This step is irreversible. After closing the SoC it will only boot signed images. 5. Create dual bootloader image We can concatenate our binaries to create a single file, let's use 2MB distance between primary and secondary images: For the working primary image: objcopy -I binary -O binary --pad-to 0x200000 --gap-fill=0x00 signed_flash.bin 1st-spl_pad.bin cat 1st-spl_pad.bin secondary2_nohdmifw_signed_flash.bin > 1st-spl_pad_2nd-spl.bin Or for the corrupt primary image experiment: objcopy -I binary -O binary --pad-to 0x200000 --gap-fill=0x00 signed_flash_corrupt.bin 1st-spl_pad.bin cat 1st-spl_pad.bin secondary2_nohdmifw_signed_flash.bin > 1st-spl_pad_2nd-spl.bin Program it to the SD card on 0x8400 offset (33k) dd if=1st-spl_pad_2nd-spl.bin of=<sd path> bs=1024 seek=33 && sync 6. Add Secondary image table Follow the format on the RM, this is only 20 bytes long. For a 2MB distance between the table and the secondary image we can use "0x1000" on the firstSectorNumber field. 2MB/512 = 4096 (0x1000) The perl script attached, genSecTable.pl, can be used to generate it. perl genSecTable.pl 0x1000 Program it to the SD card on 0x8200 offset dd if=secTable.bin of=<sd path> bs=1 seek=$((0x8200)) && sync 7. Verify secondary image is booting If using the corrupt primary image, you should see the spl with the "Secondary U-Boot SPL..." banner. You can also read the persist secondary boot bit. u-boot=> md.l 0x30390098 1 30390098: 40000000 ...@ The work can be extended patching spl for in case of u-boot authentication failure, spl can try to authenticate and jump to the secondary u-boot.

Sometimes it is helpful/faster to build a i.MX8MM boot binary outside of the Yocto environment. There are instructions on how to accomplish this on different places, this document tries to provide an example for the i.MX8M Mini LPDDR4 EVK, whenever possible pointing how to build for other boards. For the 8MM SoC a boot image is generated by imx-mkimage tool and requires: - u-boot - ARM trusted firmware image - ddr training firmware 1. Download and Build u-boot: mkdir imx-boot-bin cdimx-boot-bin git clone https://source.codeaurora.org/external/imx/uboot-imx.git cd uboot-imx/ git checkout -b imx_v2019.04_4.19.35_1.1.0 origin/imx_v2019.04_4.19.35_1.1.0 (Optional) Here you can "git log -1" to check that the commit matches SRCREV on the recipe. Next, use the BSP SDK script to setup the cross compilation environment, instructions on how to build it are here. source /opt/fsl-imx-wayland/4.19-warrior/environment-setup-aarch64-poky-linux export ARCH=arm Build make clean Supported boards have configuration files on "configs". Using the LPDDR4 EVK here: make imx8mm_evk_defconfig make 2.   Download and build the ARM Trusted Firmware cd .. git clone https://source.codeaurora.org/external/imx/imx-atf.git cd imx-atf/ git checkout -b imx_4.19.35_1.1.0 origin/imx_4.19.35_1.1.0 (Optional) Again, you can "git log -1" to check that the commit matches SRCREV on the recipe. https://source.codeaurora.org/external/imx/meta-fsl-bsp-release/tree/imx/meta-bsp/recipes-bsp/imx-atf/imx-atf_2.0.bb?h=warrior-4.19.35-1.1.0 Build: make PLAT=imx8mm bl31 If you run into this error: aarch64-poky-linux-ld.bfd: unrecognized option '-Wl,-O1' aarch64-poky-linux-ld.bfd: use the --help option for usage information make: *** [Makefile:712: build/imx8mm/release/bl31/bl31.elf] Error 1 try:  unset LDFLAGS make PLAT=imx8mm bl31 3. Download the LPDDR4 training binaries It is on firmware-imx, recipe is here: https://source.codeaurora.org/external/imx/meta-fsl-bsp-release/tree/imx/meta-bsp/recipes-bsp/firmware-imx?h=warrior-4.19.35-1.1.0 cd .. mkdir firmware-imx cd firmware-imx wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.5.bin chmod a+x firmware-imx-8.5.bin ./firmware-imx-8.5.bin 4. Download imx-mkimage and build the boot image cd .. git clone https://source.codeaurora.org/external/imx/imx-mkimage.git cd imx-mkimage/ git checkout -b imx_4.19.35_1.1.0 origin/imx_4.19.35_1.1.0 (Optional) "git log -1" matches SRCREV on: https://source.codeaurora.org/external/imx/meta-fsl-bsp-release/tree/imx/meta-bsp/recipes-bsp/imx-mkimage/imx-mkimage_git.inc?h=warrior-4.19.35-1.1.0 Now, you can check the build targets and required binaries at iMX8M/soc.mak For the flash_evk for the imx8mm we will need binaries: u-boot: u-boot-spl.bin, u-boot-nodtb.bin, fsl-imx8mm-evk.dtb  ARM trusted firmware: bl31.bin LPDDR4 files: lpddr4_pmu_train_1d_imem.bin lpddr4_pmu_train_1d_dmem.bin lpddr4_pmu_train_2d_imem.bin lpddr4_pmu_train_2d_dmem.bin mkimage for mkimage_uboot Copy all these to imx-mkimage/iMX8M/ cp ../uboot-imx/spl/u-boot-spl.bin iMX8M/ cp ../uboot-imx/u-boot-nodtb.bin iMX8M/ cp ../uboot-imx/arch/arm/dts/fsl-imx8mm-evk.dtb iMX8M/ cp ../imx-atf/build/imx8mm/release/bl31.bin iMX8M/ cp ../firmware-imx/firmware-imx-8.5/firmware/ddr/synopsys/lpddr4_pmu_train_* iMX8M/ cp ../uboot-imx/tools/mkimage iMX8M/mkimage_uboot Build: make SOC=iMX8MM flash_evk Output binary is on ./iMX8M/flash.bin 5. Program on the SD Card: sudo dd if=iMX8M/flash.bin of=/dev/<path to your sd> bs=1024 seek=33