1. HW Environment:     IMX8mm-evk board.     ITE6122 mipi dsi to lvds bridge board.     B101UAN02.1 1920x1200 LVDS panel   2. SW Environment:     IMX YOCTO 4.14.98-2.0.0ga release.   3. Patch operation:     a. git clone https://source.codeaurora.org/external/imx/linux-imx.git     b. git checkout -b  imx_4.14.98_2.0.0_ga remotes/origin/imx_4.14.98_2.0.0_ga     c. patch -p1 < ../ite6122_imx8mm_4.14.98ga_18c3fd8837fc3c6_0512.patch   4. Tested on imx8mm-evk board:   5. Attached doc list:      i.MX8MM(MN)_IT6122FN_ user guide_V0.20.pdf ------  ite6122 bridge board HW guide      i.MX8MM(MN)_IT6122FN_V11_20200513.pdf  ------  ite6122 bridge board SCH      ite6122_imx8mm_4.14.98ga_18c3fd8837fc3c6_0512.patch  ------  Linux kernel driver patch      B101UAN02.1_Ver1.0.pdf -------  panel spec              2020/10/30： 6122-hw-version-2010-10-30.zip ------ updated new HW design.        

By default Linux BSP will work with LVDS screen on i.MX 6SoloX SABRE board. To enable MCIMX28LCD on the board, following need to be modified in u-boot: setenv panel 'MCIMX28LCD' setenv fdt_file 'imx6sx-sdb-lcdif1.dtb' #add video=mxc_lcdif:SEIKO-WVGA,bpp=16 to kernel command line you’re using #For example, when booting from MMC it will be: #  setenv mmcargs 'setenv bootargs console=${console},${baudrate} root=${mmcroot} video=mxc_lcdif:SEIKO-WVGA,bpp=16' saveenv

I've been asked to help to upload the doc in MPU support space. The doc describes some ideas about how to support a customer to enable a mipi-csi2 sensor connected with i.MX6DQ/6DL. Hope this may be helpful.

The i.MX Android O8.0.0_1.0.0 GA release is now available from IMX_SW page. Overview -> BSP Updates and Releases -> Android 8.0.0 Oreo (O8.0.0_1.0.0, 4.9 kernel)   Files available: # Name Description 1 android_O8.0.0_1.0.0_docs.tar.gz i.MX Android O8.0.0_1.0.0 BSP Documentation 2 imx-o8.0.0_1.0.0_ga.tar.gz i.MX Android O8.0.0_1.0.0 proprietary surce code for i.MX 6QuadPlus, i.MX 6Quad, i.MX 6DualPlus, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo  i.MX 6Sololite, i.MX6SX and i.MX7D 3 android_O8.0.0_1.0.0_image_6dqpsabreauto.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - SABRE for Automotive Infotainment based on i.MX 6QuadPlus, i.MX 6Quad, and i.MX 6DualLite 4 android_O8.0.0_1.0.0_image_6dqpsabresd.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - SABRE Platform and SABRE Board based on i.MX 6QuadPlus, i.MX 6Quad and i.MX 6DualLite. 5 android_O8.0.0_1.0.0_image_6slevk.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - i.MX 6Sololite evaluation kit. 6 android_O8.0.0_1.0.0_image_6sxsabresd.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - SABRE Board based on i.MX 6SoloX 7 android_O8.0.0_1.0.0_image_6sxsabreauto.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - SABRE for Automotive infotainment based on i.MX 6SoloX 8 android_O8.0.0_1.0.0_image_7dsabresd.tar.gz Binary Demo Files of Android O8.0.0_1.0.0 BSP - SABRE Board based on i.MX 7Dual 9 fsl_aacp_dec_O8.0.0_1.0.0.tar.gz AAC Plus Codec for O8.0.0_1.0.0 10 android_O8.0.0_1.0.0_tools.tar.gz Manufacturing Toolkit and VivanteVTK for O8.0.0_1.0.0   Supported Hardware SoC/Boards: i.MX 6Quad, i.MX 6QuadPlus, and i.MX 6DualLite SABRE-SD board and platform i.MX 6Quad, i.MX 6QuadPlus, and i.MX 6DualLite SABRE-AI board and platform i.MX 6SoloLite EVK platform i.MX 6SoloX SABRE-SD board and platforms i.MX 6SoloX SABRE-AI board and platforms i.MX 7Dual SABRE-SD board and platform   Changes: Compared to the N7.1.2_2.0.0 release, this release has the following major changes: Upgraded the Android code base from android-7.1.2_r9 to android-8.0.0_r25. Removed the device partition and added the vendor partition. Enabled ION-based gralloc and EGL. Feature: For features please consult the release notes.   Known issues For known issues and more details please consult the Release Notes.

Use the EPDC Unit Test to exercise your EPD panel 1.  Introduction The i.MX 6Solo/6DualLite and i.MX 6SoloLite processors contain an Electrophoretic Display Controller (EPDC) designed to drive E-INK(TM) EPD panels supporting a wide variety of TFT backplanes. Detailed information about the EPDC is available in the i.MX 6Solo/6DualLite and i.MX 6SoloLite Reference Manuals. Information about programming the EPDC and integrating support for a particular panel into the Linux BSP is provided in the Linux BSP Reference Manual. Now that you have your panel hardware and software integrated, how can you tell if it is all working? Or perhaps you're using a standard panel that doesn't seem to be working - how can you test it at the lowest level? The answer is the EDPC Unit Test. 2. Running the EPDC Unit Test Most i.MX processor hardware modules have an associated unit test in the unit_tests directory of the root file system image. The basics of running the EPDC unit test are simple. After logging in as root on the debug console, change to the unit tests directory and execute the test as follows: $ cd /unit_tests $ ./mxc_epdc_fb_test.out Without any arguments, the unit test runs thirteen individual tests and takes about 8 minutes to complete. You will get a lot of output on the panel and it may not be obvious that the images are displaying correctly. Running the unit test with no arguments is a nice automated way to make sure your panel is at least displaying something, and is not causing a crash or hang. But to really verify correctness each test should be run individually and the output carefully reviewed. This can be accomplished by passing a test number option as follows: $ ./mxc_epdc_fb_test.out -n 1 To show a list of all the available options, as well as a list of the individual test numbers, use the "-h" argument. The helpful output is shown below. $ ./mxc_epdc_fb_test.out -h EPDC framebuffer driver test program. Usage: mxc_epdc_fb_test [-h] [-a] [-p delay] [-u s/q/m] [-n ]         -h        Print this message         -a        Enabled animation waveforms for fast updates (tests 8-9)         -p        Provide a power down delay (in ms) for the EPDC driver                   0 - Immediate (default)                   -1 - Never                    ms - After ms milliseconds         -u        Select an update scheme                   s - Snapshot update scheme                   q - Queue update scheme                   m - Queue and merge update scheme (default)         -n        Execute the tests specified in expression                   Expression is a set of comma-separated numeric ranges                   If not specified, tests 1-13 are run Example: ./mxc_epdc_fb_test.out -n 1-3,5,7 EPDC tests: 1 - Basic Updates 2 - Rotation Updates 3 - Grayscale Framebuffer Updates 4 - Auto-waveform Selection Updates 5 - Panning Updates 6 - Overlay Updates 7 - Auto-Updates 8 - Animation Mode Updates 9 - Fast Updates 10 - Partial to Full Update Transitions 11 - Test Pixel Shifting Effect 12 - Colormap Updates 13 - Collision Test Mode 14 - Stress Test In addition to "-n" to run individual tests, the "-a" and "-u" options are provided to set animation mode and waveform used, respectively. These options make sense only for some of the individual tests, as noted in the next section. The "-u s" (snapshot) mode purposely does not allow pending updates, so some of the tests will cause the driver to issue the following warning in snapshot mode: imx_epdc_fb: No free intermediate buffers available. The "-p" (power down delay) option allows you to specify how soon the device driver automatically powers down the controller after all pending updates have completed. The default is 0 (zero), meaning power down immediately. Use "-1" to disable power down (i.e. never power down). Sidebar: You can use another unit test, "dump-clocks.sh", to view the state of the EPDC clocks (i.e. the power state of the module). In the example below, a "1" in the third column indicates that the clock is running; a "0" indicates the clock is gated: $ ./dump-clocks.sh | grep epdc epdc_pix_clk             pll5_video_main_clk       1   26666667 epdc_axi_clk             pll2_pfd2_400M             1  198000000 3.  Individual Test Details Important! The notes below assume you are running the version of the unit test binary in the tar file attached to this How-to. Please extract the file mxc_epdc_fb_tests.out from the tar file into your rootfs unit_tests directory before running the test. Most tests begin with a screen blank operation (all white pixels). Each test works with all three update schemes (snapshot, queue, queue and merge) unless otherwise noted. 3.1 Test 1: Basic Updates Draws the following patterns: Crosshatch Squares Text Ginger image Colorbar 3.2 Test 2: Rotation Updates Draws text, squares, crosshatch, and square outlines in all rotation modes: No rotation Clockwise (90 degrees) Upside down (180 degrees) Counterclockwise (270 degrees) The square outlines are drawn first in RGB format and then in Y8 format. 3.3 Test 3: Grayscale Framebuffer Updates Draws a top half black screen and then a colorbar, rotated clockwise. First draws in normal Y8 format and then in inverted Y8 format. 3.4 Test 4: Auto-waveform Selection Updates Draws several small squares using auto-waveform selection. Note: unlike the i.MX508 EPDC driver, the i.MX 6 driver does not report the final waveform selection to user-level applications. This test also verifies that squares at non-8-bit aligned pixels can be drawn. 3.5 Test 5: Panning Updates Draws a colorbar to an off-screen region. Draws the Ginger image to the frame buffer. Sets the focus (pan) to the colorbar, then updates portions of the screen. You should see the colorbar poke through. Slowly pans from Ginger to the entire colorbar. Use pan to flip between black and white buttons. Flashes buttons using pixel inversion. Flashes buttons using panning. 3.6 Test 6: Overlay Updates Switches between the frame buffer (FB) and the alternate (overlay) frame buffer as follows: Draws Ginger to the FB. Draws the colorbar to the alternate frame buffer. Shows the FB (Ginger). Shows the alternate FB (colorbar). Shows FB again (Ginger). Shows half FB, half alternate FB. Shows cutout region of alternate FB. Shows cutout in upper corner. Shows black screen. Shows clockwise-rotated text overlay in center. 3.7 Test 7: Auto-Updates Important! The auto-update mechanism must be enabled in the kernel configuration for this test to work. Enable it using the LTIB Kernel configuration menu item "Device Drivers->Graphics support->E-Ink Auto-update Mode Support." Also, please check the Linux BSP Release Notes for any issues with this feature. 3.8 Test 8: Animation Mode Updates Shows how normal (gray level) and monochrome (black and white) updates compare in appearance and performance. Quickly flashes back and forth between black and white screens. Draws normal squares. Draws black and white squares. Draws Ginger in gray scale and monochrome. Draws colorbar in gray scale and monochrome. Draws normal Y8 colorbar and monochrome colorbar. Draws inverted normal Y8 colorbar and inverted monochrome colorbar. You can run this test in animation mode using the "-a" command line option. Animation mode only updates monochrome pixels, so you will notice a drawing speed improvement. Also, you will see the implementation of one of the "rules" of using this mode: The screen must be blanked (all white or all black) when switching in and out of animation mode. 3.9 Test 9: Fast Updates Animates a square across the screen and down one side. This test can also be run in animation mode using "-a". See the animation mode notes in the Test 8 description above. 3.10 Test 10: Partial to Full Update Transitions Draws small gray squares using separate updates in partial update mode (only pixels that change are updated). Then re-draws the entire screen in one update using full update mode. In full update mode, you will notice the entire screen transition from black to the final grey value. 3.11 Test 11: Test Pixel Shifting Effect Draws a short, two pixel line and then sends two updates one pixel apart in distance and 5 seconds apart in time. Nothing much to see here; just verifies that a one pixel update shift works. 3.12 Test 12: Colormap Updates Creates a colormap and uses it to draw full screen blanks and to draw a color bar. In this test, you should follow along with the text printed in the debug console and verify each state: Screen should be black. Screen should be white now. Screen should still be white. Should be inverted color bar (white to black, left to right). Colorbar again, with no CMAP (black to white, left to right). Posterized colorbar. In the above output, "CMAP" means colormap and "Posterized colorbar" is a colorbar drawn from only black and white components. 3.13 Test 13: Collision Test Mode Draws two overlapping rectangles. Tests for collision on the first rectangle, which should result in the message: Collision test result = 0 Then draws the same overlapping rectangles, this time testing for collision on the second rectangle. The result should be: Collision test result = 1 Note: This test cannot be run using the snapshot scheme. If you try to use "-u s" it will print a message and return. 3.14 Test 14: Stress Test Draws thousands of random rectangles on the screen in different rotations. Runs for about 8 minutes. This test must be explicitly specified on the command line; it does not run by default. For example: $ ./mxc_epdc_fb_test.out -n 14 Note: This test cannot be run using the snapshot scheme. If you try to use "-u s" it will print a message and return. 4. Customizing A great way to know what's really going on in each test is to look at the source code. You may want to customize the source as well - say to add a new test that exercises some cool feature of your panel. Fortunately, the source is included in the BSP distribution so you can extract, customize, and rebuild it as needed. The magic of LTIB is beyond the scope of this article, but here are some hints: # Extract the unit test source from the imx-test package: $ ./ltib -m prep -p imx-test # Source is now in rpm/BUILD/imx-test-12.08.00/test/mxc_fb_test/mxc_epdc_fb_test.c (your package version number my be different). # Build from source: $ ./ltib -m scbuild -p imx-test # Deploy all unit test binaries to ltib rootfs directory: $ ./ltib -m scdeploy -p imx-test # Alternatively you can copy just the epdc unit test binary as follows: $ sudo cp rpm/BUILD/imx-test-12.08.00/platform/IMX6S/mxc_epdc_fb_test.out rootfs/unit_tests/ As noted in the Individual Test Details section, you should replace the file mxc_epdc_fb_test.c referenced above with the one found in the tar file attached to this How-to. 5. Something is wrong! Of course there are many things that can go wrong that are beyond the scope of this article, but assuming your hardware is working and the panel options are correctly configured in the BSP (again, beyond our scope), here are some things to check: Is the kernel configured correctly for EPDC support? Check that the following item is enabled in the LTIB Kernel configuration menu: "Device Drivers->Graphics support->E-Ink Panel Framebuffer." Are the U-boot kernel command line arguments set correctly for EPDC? For example, "video=mxcepdcfb:E060SCM consoleblank=0". The "consoleblank=0" command is useful to prevent entering low power suspend mode while you are testing. Does the "Tux" image display correctly on your panel after system boot? If so, the EPDC driver was a least able to perform the initial framebuffer update to your panel. Note: for Tux to display at boot, you need to disable LCDIF support at "Device Drivers->Graphics support->Support MXC ELCDIF framebuffer." Are there any EPDC-related error messages in the kernel log after boot? You can check with "dmesg | grep epdc".

Some customers often use LVDS LCD with low resolution on i.MX6 platform, such as 320x240, but by defualt , linux bsp doesn't support low frequency pixel clock for LVDS module input. Question:     When we port LVDS LCD with 320x240 resolution to android4.2.2, we found pixel clock is not correct, it always output 38.9MHz, it is no probem for big resolution , for example 1024x768, but the clock we need for 320x240 LCD is 6.4MHz.     According to the quesiton, Let us check IPU & LDB clock in i.MX6 datasheet at first : From above table, if ldb clock is from IPU, we will not get 6.4MHz pixel clock, so we will have to adjust its source clock: The following steps are procedure that ports LVDS LCD with 320x240 resolution to i.MX6Q. 1. Adding LVDS LCD timing structure to ldb.c static struct fb_videomode ldb_modedb[] = { {       "LDB-XGA", 60, 320, 240, 155914,       38, 20,       15, 4,       30, 3,       0,       FB_VMODE_NONINTERLACED,       FB_MODE_IS_DETAILED, }, {      "LDB-1080P60", 60, 1920, 1080, 7692,      100, 40,      30, 3,      10, 2,      0,      FB_VMODE_NONINTERLACED,      FB_MODE_IS_DETAILED,}, }; 2.Modifying clock source of ldb module Checking /arch/arm/mach-mx6/clock.c, we can find there are 3 ldb's clock source : &pll5_video_main_clk, &pll2_pfd_352M, &pll2_pfd_400M, static int _clk_ldb_di1_set_parent(struct clk *clk, struct clk *parent) {        u32 reg, mux;        int rev = mx6q_revision();        reg = __raw_readl(MXC_CCM_CS2CDR)               & ~MXC_CCM_CS2CDR_LDB_DI1_CLK_SEL_MASK;        mux = _get_mux6(parent, &pll5_video_main_clk,               &pll2_pfd_352M, &pll2_pfd_400M,               (rev == IMX_CHIP_REVISION_1_0) ?                &pll3_pfd_540M :       /* MX6Q TO1.0 */                &mmdc_ch1_axi_clk[0],     /* MX6Q TO1.1 and MX6DL */               &pll3_usb_otg_main_clk, NULL);        reg |= (mux << MXC_CCM_CS2CDR_LDB_DI1_CLK_SEL_OFFSET);        __raw_writel(reg, MXC_CCM_CS2CDR);        return 0; } By default, pll2_pfd_352M is configured as the clock source of ldb: clk_set_parent(&ldb_di0_clk, &pll2_pfd_352M);        clk_set_parent(&ldb_di1_clk, &pll2_pfd_352M); We should change the clock source to be pll5_video_main_clk clk_set_parent(&ldb_di0_clk, &pll5_video_main_clk,);        clk_set_parent(&ldb_di1_clk, &pll5_video_main_clk,); 3. Configuring initial clock in board-mx6q_sabresd.c static struct ipuv3_fb_platform_data sabresd_fb_data[] = {        { /*fb0*/        .disp_dev = "ldb",        .interface_pix_fmt = IPU_PIX_FMT_RGB666,        .mode_str = "LDB-XGA",        .default_bpp = 16,        .int_clk = false,        .late_init = false, } int_clk=false means LDB clock is from PLL2_PFD_352 or pll5_video_main_clk; int_clk=true mean LDB clock if from IPU. OK, after doing above steps, LVDS LCD with low resolution should normally work. Freescale TICS team Weidong.sun 2015-08-18

For long I looked for a working tutorial to build Qt5 with YOCTO (Yocto Training - HOME) both the libraries for the board image and also a toolchain to build Qt5 applications for the board. See the full tutorial here: Building Qt5 using yocto on Wandboard - Wandboard Wiki The Tutorial is written for the Wandboard that also uses an i.MX6 CPU but you can adapt the tutorial for most of the boards of the i.MX6 family I think - in my case it worked with the i.MX6 SABRE AI without problems. You only have to adjust the sysroot and maybe also the toolchain-path because the wiki entry is a little bit older Ask your questions for this topic - maybe I can help.

Question: Is it true ture that MX6 VPU is capable of encoding dual H.264 streams that are 1024x600 at 60fps?  There are slides that claim three 720p30 streams or two 1080p30 streams simultaneously. There is little guidance as to what the VPU limits in resolution, frame rate and bit rate are for other resoluitons and frame rates. Is there any information that can be used to decide if  the VPU can encode an arbitrary video stream or multiple arbitrary video streams?  Since memory bandwidth will enter into this decision at some point has anyone quantified the memory bandwidth requirements verses video resolution and frame rate? Answer: Maximum supported trhoughput,  is 72,576,000 pixels /s @ VPU frecuency of 266 mhz 2 x  1024 x 600 x 60hz = 73,728,000 So this is not supported. If framerate is lower i.e.  30hz  then it will be supported.

 This article uses i.MX Linux® User's Guide, Rev. L4.1.15_2.1.0-ga, 05/2017 as an example (it may be found as attachment), please refer to section 4.5.12 (How to build U-Boot and Kernel in standalone environment).   First, generate a development SDK, which includes the tools, toolchain, and small rootfs to compile against to put on the host machine.     • Generate an SDK from the Yocto Project build environment with the following command. To set up the Yocto Project build environment, follow the steps in the i.MX Yocto Project User's Guide (IMXLXYOCTOUG). In the following command, set <Target-Machine> to the machine you are building for.   <Target-Machine> may be one of the following :   • imx6qpsabreauto • imx6qpsabresd • imx6ulevk • imx6ull14x14evk • imx6ull9x9evk • imx6dlsabreauto • imx6dlsabresd • imx6qsabreauto • imx6qsabresd • imx6slevk • imx6sllevk • imx6solosabreauto • imx6solosabresd • imx6sxsabresd • imx6sxsabreauto • imx7dsabresd  The «populate_sdk» generates an script file that sets up environment without Yocto Project. This SDK should be updated for each release to pick up the latest headers, toolchain, and tools from the current release.   $ DISTRO=fsl-imx-fb MACHINE=<Target-Machine> source fsl-setup-release.sh -b build-fb   $ DISTRO=fsl-imx-fb MACHINE=<Target-Machine> bitbake core-image-minimal -c populate_sdk   or   $ bitbake meta-toolchain       • From the build directory, the bitbake was run in, copy the sh file in tmp/deploy/sdk to the host machine to build on and execute the script to install the SDK. The default location is in /opt but can be placed anywhere on the host machine.     Note. Each time you wish to use the SDK in a new shell session, you need to source the environment setup script e.g.    $ . /opt/fsl-imx-fb/4.1.15-2.0.0/environment-setup-cortexa9hf-neon-poky-linux-gnueabi   or    $ source /opt/fsl-imx-fb/4.1.15-2.0.0/environment-setup-cortexa9hf-neon-poky-linux-gnueabi   From  Yocto Project Mega-Manual  Note By default, this toolchain does not build static binaries. If you want to use the toolchain to build these types of libraries, you need to be sure your image has the appropriate static development libraries. Use the  IMAGE_INSTALL  variable inside your  local.conf  file to install the appropriate library packages. Following is an example using  glibc  static development libraries:      IMAGE_INSTALL_append = " glibc-staticdev"   On the host machine, these are the steps to build U-Boot and Kernel:  • On the host machine, set the environment with the following command before building.   $ export CROSS_COMPILE=/opt/fsl-imx-fb/4.1.15/environment-setup-cortexa9hf-vfp-neon-pokylinux-gnueabi   $ export ARCH=arm • To build U-Boot, find the configuration for the target boot. In the following example, i.MX 6ULL is the target.     Download source by cloning with   $ git clone http://git.freescale.com/git/cgit.cgi/imx/uboot-imx.git -b imx_v2016.03_4.1.15_2.0.0_ga   $ cd uboot-imx $ make clean $ make mx6ull_14x14_evk_defconfig $ make u-boot.imx   • To build the kernel, execute the following commands:   Download source by cloning with   $ git clone http://git.freescale.com/git/cgit.cgi/imx/linux-imx.git -b imx_4.1.15_2.0.0_ga   $ cd linux-imx $ make defconfig $ make   • To build an application (Hello World) as test.c:   $ source /opt/fsl-imx-fb/4.1.15-2.0.0/environment-setup-cortexa9hf-neon-poky-linux-gnueabi $ cd ~/test/ $ arm-poky-linux-gnueabi-gcc --sysroot=/opt/fsl-imx-fb/4.1.15-2.0.0/sysroots/cortexa9hf-neon-poky-linux-gnueabi -mfloat-abi=hard test.c To check if the the compiled code (a.out) is ARM executable   $ file ./a.out   ./a.out: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 2.6.32, BuildID[sha1]=0e5c22dcf021748ead2c0bd51a4553cb7d38f6f2, not stripped   Copy file a.out to target Linux filesystem and before run it check again :   root@imx6ul7d:/unit_tests/1# file a.out   a.out: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 2.6.32, BuildID[sha1]=0e5c22dcf021748ead2c0bd51a4553cb7d38f6f2, not stripped   To define what Linux libs are needed to run our application :   root@imx6ul7d:/unit_tests/1# ldd a.out     linux-vdso.so.1 (0x7ee93000)   libc.so.6 => /lib/libc.so.6 (0x76e64000)   /lib/ld-linux-armhf.so.3 (0x76f9d000)   If some libs are not located in the filesystem you can observe the following message :   -sh: root@imx6ul7d:/unit_tests/1#./a.out: No such file or directory   Finally - run a.out:   root@imx6ul7d:/unit_tests/1# ./a.out Hello World root@imx6ul7d:/unit_tests/1#

  IMX6 UL boot process is described in Chapter 8 (System Boot) of the Reference Manual. Also you may look at the following Community regarding i.MX6 boot ROM activity. How to build bootable SD image (for i.MX6 SL as example)  U-boot is used as Linux bootloader and U-boot image should be located in SD area, used by i.MX6 boot ROM. The simplest way to get bootable SD card is just to copy system image in so called .sdcard format. Such image is prepared in Yocto by default and can be transfered to SD card with Linux dd command or Windows win32diskimager utility. Guide to the .sdcard format  Win32 Disk Imager download | SourceForge.net   The full SD image (.sdcard) should contain all parts, needed for Linux boot (U-boot, kernel, dtb, file system), maybe except U-boot environment. Carry out the following command to copy the SD card image to the SD/MMC card. Change sdx below to match the one used by the SD card. $ sudo dd if=<image name>.sdcard of=/dev/sdx bs=1M && sync   Note, U-boot environment (described below) should be set (and saved) in U-boot after the first start.   In any case it makes sense to understand general structure and implementation details of bootable SD card. Instructions are provided in section 4.3 (Preparing an SD/MMC card to boot) of i.MX Linux® User's Guide in Linux doc package (L4.1.15_2) http://www.nxp.com/webapp/Download?colCode=L4.1.15_2.1.0_LINUX_DOCS&Parent_nodeId=1337699481071706174845&Parent_pageType…  Summary page : i.MX 6 / i.MX 7 Series Software and Development Tool|NXP    For a Linux image to be able to run, four separate pieces are needed: • Linux OS kernel image (zImage) • Device tree file (*.dtb) • U-Boot bootloader image • Root file system (*.ext3 or *.ext4)   The mentioned files may be found in demo images on NXP Web or generated with Yocto. After a build is complete, the created image resides in <build directory>/tmp/deploy/images The device tree file (.dtb) contains board and configuration-specific changes to the kernel. Change the device tree file to change the kernel for a different i.MX board or configuration.    By default, the kernel image and DTB are located on FAT partition without a fixed raw address on the SD card. Generally fix addresses / blocks of SD card may be applied for kernel and DTB location. The users have to change the U-Boot boot environment if the fixed raw address is required. In example below the following image layout on SD card is assumed : Start address (sectors) = 0x400 bytes (2) for U-boot (i.MX6 boot ROM reads first 4K bytes of SD card). Start address (sectors) = 0xa00000 bytes (20480) for FAT partition, size=500MB, intended for Kernel zImage and DTBs. Start address (sectors) = 0x25800000 bytes (1228800) for rootfs.    Preparing the card   An SD/MMC card reader, such as a USB card reader, is required. Any Linux distribution can be used. Further follow instructions in sections 4.3.1 (Preparing the card), 4.3.3 (Partitioning the SD/MMC card), 4.3.4 (Copying a bootloader image), 4.3.5 (Copying the kernel image and DTB file), 4.3.6 Copying the root file system (rootfs) of attached "i.MX_Graphics_User's_Guide.pdf". The next step - try to insert the SD card to slot in i.MX6UL board, select proper boot options for SD boot and power the system. U-boot prompt should appear. Finally it is needed to configure environment for further Linux boot from SD. U-Boot > setenv mmcdev 1 U-Boot > setenv mmcpart 1 U-Boot > setenv mmcroot '/dev/mmcblk1p2 rootwait rw' U-Boot > setenv loadaddr 0x80800000 U-Boot > setenv fdt_addr=0x83000000 U-Boot > setenv fdt_file imx6ul-9x9-evk.dtb U-Boot > setenv mmcpart 1 U-Boot > setenv loadfdt 'fatload mmc ${mmcdev}:${mmcpart} ${fdt_addr} ${fdt_file}' U-Boot > setenv loadkernel 'fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} zImage' U-Boot > setenv bootcmd 'mmc dev ${mmcdev}; run loadkernel; run mmcargs; run loadfdt; bootz $ {loadaddr} - ${fdt_addr};' U-boot > saveenv fdt_file should be set for your case ( on example “imx6ul-9x9-evk.dtb”) Try reboot with new environment.

Using a RAW NAND is more difficult compared to eMMC, but for lower capacity it is still cheaper. Even with the ONFI (Open NAND Flash Interface) you can face initialization issue you can find by measure performance. I will take example of a non-well supported flash, I have installed on my evaluation board (SABRE AI). I wanted to do a simple performance test, to check roughly the MB/s I can expected with this NAND. One of a simplest test is to use the dd command: root@imx6qdlsolo:~# time dd if=/dev/mtd4 of=/dev/null 851968+0 records in 851968+0 records out 436207616 bytes (436 MB, 416 MiB) copied, 131.8884 s, 3.3 MB/s ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ As my RAW was supposed to work in EDO Mode 5, I could expect more than 20MB/s. To check what was wrong, read you kernel startup log: Booting Linux on physical CPU 0x0 Linux version 4.1.15-2.0.0+gb63f3f5 (bamboo@yb6) (gcc version 5.3.0 (GCC) ) #1 SMP PREEMPT Fri Sep 16 15:02:15 CDT 2016 CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c53c7d CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache Machine model: Freescale i.MX6 DualLite/Solo SABRE Automotive Board [...] Amd/Fujitsu Extended Query Table at 0x0040 Amd/Fujitsu Extended Query version 1.3. number of CFI chips: 1 nand: device found, Manufacturer ID: 0xc2, Chip ID: 0xdc nand: Macronix MX30LF4G18AC nand: 512 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64 gpmi-nand 112000.gpmi-nand: mode:5 ,failed in set feature. Bad block table found at page 262080, version 0x01 Bad block table found at page 262016, version 0x01 nand_read_bbt: bad block at 0x00000a7e0000 nand_read_bbt: bad block at 0x00000dc80000 4 cmdlinepart partitions found on MTD device gpmi-nand Creating 4 MTD partitions on "gpmi-nand":‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ On line 13 you can read "mode:5, failed in set feature", meaning you are not in mode 5... so you have the "relaxed" timing you have at boot. After debuging your code (I have just remove the NAND back reading security check), you can redo the test: root@imx6qdlsolo:~# time dd if=/dev/mtd4 of=/dev/null 851968+0 records in 851968+0 records out 436207616 bytes (436 MB, 416 MiB) copied, 32.9721 s, 13.2 MB/s‍‍‍‍‍‍‍‍‍‍‍‍ So you multiplied the performances by 4! Anyway, you have a better tool to measure your NAND performance, it is mtd_speedtest, but you have to rebuild your kernel. In Yocto, reconfigure your kernel (on your PC of couse!): bitbake virtual/kernel -c menuconfig‍‍‍ Choose in the menu "Device Drivers" -> "Memory Technology Device (MTD) support" -> "MTD tests support", even it it not recommended! bitbake virtual/kernel -f -c compile bitbake virtual/kernel -f -c build bitbake virtual/kernel -f -c deploy‍‍‍‍‍‍‍‍‍ Then reflash you board (kernel + rootfs as tests are .ko files): Then you can do more accurate performance test: insmod /lib/modules/4.1.29-fslc+g59b38c3/kernel/drivers/mtd/tests/mtd_speedtest.ko dev=2 ================================================= mtd_speedtest: MTD device: 2 mtd_speedtest: MTD device size 16777216, eraseblock size 131072, page size 2048, count of eraseblocks 128, pages per eraseblock 64, OOB size 64 mtd_test: scanning for bad eraseblocks mtd_test: scanned 128 eraseblocks, 0 are bad mtd_speedtest: testing eraseblock write speed mtd_speedtest: eraseblock write speed is 4537 KiB/s mtd_speedtest: testing eraseblock read speed mtd_speedtest: eraseblock read speed is 16384 KiB/s mtd_speedtest: testing page write speed mtd_speedtest: page write speed is 4250 KiB/s mtd_speedtest: testing page read speed mtd_speedtest: page read speed is 15784 KiB/s mtd_speedtest: testing 2 page write speed mtd_speedtest: 2 page write speed is 4426 KiB/s mtd_speedtest: testing 2 page read speed mtd_speedtest: 2 page read speed is 16047 KiB/s mtd_speedtest: Testing erase speed mtd_speedtest: erase speed is 244537 KiB/s mtd_speedtest: Testing 2x multi-block erase speed mtd_speedtest: 2x multi-block erase speed is 252061 KiB/s mtd_speedtest: Testing 4x multi-block erase speed mtd_speedtest: 4x multi-block erase speed is 256000 KiB/s mtd_speedtest: Testing 8x multi-block erase speed mtd_speedtest: 8x multi-block erase speed is 260063 KiB/s mtd_speedtest: Testing 16x multi-block erase speed mtd_speedtest: 16x multi-block erase speed is 260063 KiB/s mtd_speedtest: Testing 32x multi-block erase speed mtd_speedtest: 32x multi-block erase speed is 256000 KiB/s mtd_speedtest: Testing 64x multi-block erase speed mtd_speedtest: 64x multi-block erase speed is 260063 KiB/s mtd_speedtest: finished =================================================‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ You can now achieve almost 16MB/s, better than the dd test. Of course you cannot achieve more than 20MB/s, but you are not that far, and the NAND driver need optimizations. To redo the test: rmmod /lib/modules/4.1.29-fslc+g59b38c3/kernel/drivers/mtd/tests/mtd_speedtest.ko insmod /lib/modules/4.1.29-fslc+g59b38c3/kernel/drivers/mtd/tests/mtd_speedtest.ko dev=2 To check your NAND is in EDO mode 5, you can check your clock tree: /unit_tests/dump-clocks.sh clock          parent   flags    en_cnt pre_cnt      rate [...] gpmi_bch_apb   ---      00000005   0       0       198000000 gpmi_bch       ---      00000005   0       0       198000000 gpmi_io        ---      00000005   0       0        99000000 gpmi_apb       ---      00000005   0       0       198000000‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ The IO are clocked now at 99MHz, thus you can read at 49.5MHz (20ns in EDO mode 5 definition).

Please make sure design is follow below checking list before checking this guide. HW Design Checking List for i.MX6DQSDL

I²C is a communication protocol used to exchange information between cores. To see more about I²C, please follow this link Wikipedia:I²C. Enable I2C-tools in LTIB into Package List: Reboot your file system, there are three new I²C commands: i2cdetect, i2cdump and i2cset. All examples below were tested in a iMX27ADS, but this programs seems to have the same behavior to all platforms. Detecting busses This command lists all installed bus. mx27# i2cdetect -l i2c-0   unknown         MXC I2C Adapter                         Algorithm unavailable There is one installed bus with address 0. Installed Chips I2cdetect shows the installed chips too. mx27# i2cdetect 0     WARNING! This program can confuse your I2C bus, cause data loss and worse!     I will probe file /dev/i2c/0.     I will probe address range 0x03-0x77.         0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f 00:          XX XX XX XX XX XX XX XX XX XX XX XX XX 10: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX 20: XX XX XX XX XX XX XX XX XX XX XX XX XX 2d XX XX 30: UU XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX 40: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX 50: XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX 60: XX XX XX XX XX XX XX XX XX XX UU XX XX XX XX XX 70: XX XX XX XX XX XX XX XX There are several cores installed into bus i2c-0. If you received an error message like this: # i2cdetect 0 Error: Could not open file `/dev/i2c-0' or `/dev/i2c/0': No such file or directory You will need to create the special file /dev/i2c-0 : # mknod /dev/i2c-0 c 89 0 Chip Registers i2cdump shows a list of all registers for a core. For example, the command above shows registers for core with address 0x6a: mx27# i2cdump 0 0x6a No size specified (using byte-data access)     WARNING! This program can confuse your I2C bus, cause data loss and worse!     I will probe file /dev/i2c/0, address 0x6a, mode byte         0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef 00: 00 00 28 00 00 03 15 03 00 00 00 00 00 00 03 01    ..(..???......?? 10: 04 01 00 00 04 01 00 00 17 41 1d 00 09 09 1f 03    ??..??..?A?.???? 20: 00 00 40 00 08 00 0c 00 0f 01 00 00 00 00 08 11    ..@.?.?.??....?? 30: 00 0f 05 fe 0b 00 00 00 82 00 0c 02 00 00 01 00    .????...?.??..?. 40: 21 f0 7c 1f 00 00 01 00 7a 40 80 38 00 01 47 00    !?|?..?.z@?8.?G. 50: 3c 00 17 21 1b 1b 24 9f 00 3e 0f 0f 60 05 cd 03    <.?!??$?.>??`??? 60: 89 04 89 01 02 00 0a 05 00 19 ff 03 24 0f 78 00    ?????.??.?.?$?x. 70: 00 b2 06 14 04 08 00 a3 c8 15 05 15 3c 00 00 20    .?????.?????<.. 80: 07 2f 07 00 00 00 00 00 00 00 00 ff 03 1a 1a 1a    ?/?.........???? 90: 1a 1a 40 03 00 00 00 00 00 00 00 00 00 00 e4 00    ??@?..........?. a0: 00 02 4d 00 96 00 1d 00 a0 00 db 00 7e 00 00 00    .?M.?.?.?.?.~... b0: 00 00 00 00 00 00 f0 00 00 00 00 00 00 00 00 00    ......?......... c0: 00 00 00 00 48 9c 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a    ....H??????????? d0: 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a    ???????????????? e0: 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a    ???????????????? f0: 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a 1a    ???????????????? Setting a register To change some register value, use i2cset like in example below: mx27# i2cset 0 0x6a 01 0x0008 w     WARNING! This program can confuse your I2C bus, cause data loss and worse!     I will write to device file /dev/i2c/0, chip address 0x6a, data address     0x00, data 0x08, mode word. Value 0x8 written, readback matched Where: 0 is the bus address 0x6a is the slave address 01 is the register address 0x0008 is the new value for register w is the word mode for the setting

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

INTRODUCTION REQUIREMENTS HARDWARE CONNECTIONS IMPLEMENTATION FUNCTIONAL DEMONSTRATION     1. INTRODUCTION   This document explains how to establish communication between the A9 core running Linux and the M4 core running an Arduino sketch on a UDOO NEO board to remotely control a robotic arm over Wi-Fi.   Figure 1: UDOO NEO board connected to the robotic arm   For more information about getting started with UDOO NEO board please refer to: Introduction - UDOO Neo Docs     2. REQUIREMENTS a) UDOO NEO board with UDOObuntu image and proper connectivity. The Linux image used is UDOObuntu 2 RC1 or RC2 (Ubuntu 14.04), available for download from the following link:      ARM Development Boards | Extended Support from UDOO For creating a bootable SD card and other basic setup please refer to the following guidelines:      Very First Start - UDOO Neo Docs Then, it is required to install the proper drivers to ensure connectivity, including USB communication with Linux terminal of the target board. Please refer to the link below:      Usb Direct Connection - UDOO Neo Docs b) The robotic arm itself. In this case, the used arm has four servomotors: three for articulation and one for open/close the clamp. c) A Wi-Fi router, and an additional Wi-Fi device with any SSH client application for the remote control of the arm.     3. HARDWARE CONNECTIONS   a) The first connection to consider is the USB Direct connection of the UDOO NEO board with the host PC, in order to configure the Wi-Fi network and remotely view of the desktop (VNC client) for Arduino sketch programming.   b) Then, it is required to consider the arm connection, which consists of four servomotors. Therefore, the motors must be powered by a separate power supply and controlled by four PWM signals. In this case, they will be connected to PWM_1, PWM_2, PWM_3 and PWM_4 signals of J4 connector (Arduino signals). Figure 2 shows the mentioned connection:   Figure 2: Servomotors connection to UDOO NEO board.     4. IMPLEMENTATION   4.1 Connecting to a Wi-Fi network. After turning on the UDOO NEO board, the USB Direct connection will install a virtual NIC on the host PC, in order to access to the “Dashboard”, a configuration webpage loaded on the NEO board that could be viewed from any web browser at address 192.168.7.2. You can connect to wireless networks by using the Web Control Panel, in Configuration/Network settings. After establishing connection with the Wi-Fi router, the Dashboard must indicate the assigned IP address of the NEO board as indicated on Figure 3. It is important to remember such address in order to establish the wireless access to the NEO board later (optionally, the NEO could be configured for a static IP address, or the router could be configure to assign the same IP address to the NEO board).   Figure 3: Dashboard showing the IP address of the NEO board.   Now the USB direct connection could be removed, as the Dashboard, remote terminal and VNC server are also available over Wi-Fi using the Wi-Fi IP address.   4.2. Programming the Arduino sketch. The remote desktop of the NEO could be viewed with any VNC client on the host PC, indicating the NEO’s IP address, user and password (same as SSH remote Terminal). The UDOObuntu image already include Arduino IDE configured for UDOO NEO board, so it is just required opening it to start writing the code. Figure 3 shows the UDOO NEO Desktop, which includes a Terminal window and the Arduino IDE. The sketch is available as attachment.   Figure 4: Desktop of UDOO NEO board.   4.3. Arduino sketch functionality. The Arduino program starts waiting for any incoming data over the serial port. After receiving any serial data, the four servomotors are initialized to the default position (90°). The serial port communication is established between a virtual serial port on Arduino side (Serial0), and the virtual serial port for the Multi-Core Communication (ttyMCC), like shown on Figure 5. For additional information please refer to the link below: Communication - UDOO Neo Docs Figure 5: Communication between cores. Once the motors are initialized, each movement is defined by a key to increase and decrease the angle position of the motors, except for the clamp, which is adjusted to open/close positions. Keys 'Q' and 'W' adjust the first motor; keys 'A' and 'S' adjust the second motor; keys 'D' and 'F' adjust the third motor, and finally, keys 'Z' and 'X' are used to open/close the clamp. Additionally, key 'R' resets all motors to default positions; key 'C' is used to enable/disable the PWM signals, and key 'V' prints the angle values of all motors. The adjust step of motors is defined with the macro “ANGLE_STEP”; the units are degrees.     5. FUNCTIONAL DEMONSTRATION   For demonstrative functionality, the UDOO NEO board running the Arduino sketch was connected to a Wi-Fi network, and it is also connected to the same network an Android phone with SSH app used to control the robotic arm. Figure 6 shows a screen capture of the mentioned app controlling the robotic arm. Figure 6: SSH app accessing to UDOO NEO.   Finally, the following video shows the functionality of the application:   Original Attachment has been moved to: robo_arm.ino.zip

Platform: imx8qm mek imx-yocto-L4.14.98_2.0.0_ga Building Step: Apply the nvp6324 patches.   Symbol: IMX8_NVP6324 [=y] Type : tristate Prompt: IMX8 NVP6324 Driver Location: -> Device Drivers -> Multimedia support (MEDIA_SUPPORT [=y]) -> V4L platform devices (V4L_PLATFORM_DRIVERS [=y]) -> MX8 Video For Linux Video Capture (VIDEO_MX8_CAPTURE [=y]) (1) -> IMX8 Camera ISI/MIPI Features support ‍‍‍‍‍‍‍‍‍ select nvp6324 to y in menuconfig(default is 'y') make Image -j8; make freescale/fsl-imx8qm-mek-nvp6324.dtb, to build kernel and dts, outputs are at  work/imx8qmmek-poky-linux/linux-imx/4.14.98-r0/build/arch/arm64/Image work/imx8qmmek-poky-linux/linux-imx/4.14.98-r0/build/arch/arm64/boot/dts/freescale/fsl-imx8qm-mek-nvp6324.dtb copy them to the sd boot partition. reboot the board, you can test the first camera with command: ./mx8_v4l2_cap_drm.out -cam 1 -ow 1280 -oh 720 mx8_v4l2_cap_drm.out is at /unit_tests/V4L2/mx8_v4l2_cap_drm.out The corresponding video device should be default to /dev/video0 ~ /dev/video3.

This tool is also for emmc user partition mirror. Just give this tool the emmc files. The typical use case is for emmc mass production by emmc offline programming. Ver 0.4.0 2/14/2017 Support Android 7 Nougat. AndroidSDCARDMirrorCreator_Version_0.4.0_02142017.tgz Ver 0.3.2: 6/13/2016 Using static link simg2img AndroidSDCARDMirrorCreator_Version_0.3.2_06132016.tgz Ver 0.3.1: 5/31/2016 Remove some redundent code   AndroidSDCARDMirrorCreator_Version_0.3.1_05312016.tgz Ver 0.3: 5/25/2016 Add Marshmallow partition layout AndroidSDCARDMirrorCreator_Version_0.3_05252016.tgz Ver 0.2: Add Lollipop partition layout 1. Directory AndroidSDCARDMirrorCreator |-- AndroidSDCARDMirrorCreator.sh        --- main script |-- CFG.INC                              --- configuration file |-- KitKat_LAYOUT.INC                    --- KitKat partition layout |-- LAYOUT.INC -> Lollipop_LAYOUT.INC    --- symbol link to partition layout |-- Lollipop_LAYOUT.INC                  --- Lollipop partition layout `-- readme.txt                           --- this file 2. Need "root" run or "sudo" to run 3. parted and kpartx must be installed    sudo apt-get instal parted kpartx 4. test pass under the debian 8.2 and ubuntu 12.04 5. The AndroidSDCARDMirrorCreator.sh will look for LAYOUT.INC.    please make symbol link to the correct partition layout.    The default symbol link has created for Lollipop_LAYOUT.INC (LAYOUT.INC -> Lollipop_LAYOUT.INC) 6. Command    AndroidSDCARDMirrorCreator.sh -c    AndroidSDCARDMirrorCreator.sh -p 7. Example:    Suppose    The AndroidSDCARDMirrorCreator directory is in    ~/AndroidSDCARDMirrorCreator       The Android Images are in    ~/SD and ~/eMMC       Sdcdard Mirror:    cd ~/SD    ~/AndroidSDCARDMirrorCreator/AndroidSDCARDMirrorCreator.sh -c    eMMC Mirror:    cd ~/eMMC    ~/AndroidSDCARDMirrorCreator/AndroidSDCARDMirrorCreator.sh -c    8. Once the Mirror has been created. Can be reused. Just use kpartx.

MX7D_DDR3_压力测试应用手册_V1_201611108.doc

When to improve kernel booting using hibernation [1], I found kernel initialized each component [2] took too much time. One solution is to remove unnecessary module to save time. Another approach is to delay those modules until user space up. Then it won’t lost some features just because hopes to gain benefit on booting speed. This is very useful since hibernation’s trigger point is at the late_initcall [3]. Kernel doesn't need do much module initialize since hibernate will restore those module status later. The detailed implementation is in the attached patch. [1]: hibernation is a technique to store system memory content to storage. Then the device can be shutdown and read the content back after power on. [2]: component means subsystem or driver. [3]: Consult kernel/power/hibernate.c, software_resume

Several customers met problem on audio codec porting. In order to figure out cpu dai setting problem or codec dai problem. Create the dummy codec for test purpose.  What this dummy codec can do This dummy codec can play up to 8 channels and record up to 6 channels. Connect SAI1 TX data pin with SAI1 RX data pin for loopback test. Environment Verified with i.MX8MM EVK  Based on Linux BSP L4.14.78 Files Kernel patch 0001-multiple-channels-dummy-audio-codec 0002-Add-capture-for-multiple-channels User space setting /etc/asound.conf /usr/share/alsa/cards/aliases.con /usr/share/alsa/cards/DUMMY.conf Audio test content PCM_48_16_8_160000_1_29_jazzshort.wav The alsa command for loopback test with multiple channels  aplay -D surround51:CARD=dummyaudio PCM_48_16_8_160000_1_29_jazzshort.wav | arecord -D surround51:CARD=dummyaudio --disable-channels --disable-format --disable-resample -f S16_LE -r 48000 -c 6 -d 5 -v test.wav