Useful information about push buttons.   Physical level.            When there is a change of voltage level on P0-P7 pins, PCA9555PW will generate interrupt on INT pin. The driver (running on SoC) can read the status of P0-P7 pins via I2C (SCL/SDA pins) and generate separate interrupts for each of P0-P7 pins. This is why this driver acts as interrupt controller. Consider next configuration:        One push button changes level on P4 pin, tempting PCA9555PW to generate interrupt. Interrupt from PCA9555PW is connected to GPIO5 IP-core (inside of SoC), and it uses line #9 of that GPIO5 module to notify CPU about interrupt. So we can say that PCA9555PW is cascaded to GPIO5 controller. GPIO5 also acts as interrupt controller, and it's cascaded to GIC interrupt controller.   Device tree properties.   The meaning of properties is as follows: interrupt-controller  property defines that device generates interrupts; it will be needed further to use this node as interrupt-parent in each push button node. #interrupt-cells defines format of interrupts property; in our case it's 2 : 1 cell for line number and 1 cell for interrupt type interrupt-parent and interrupts properties are describing interrupt line connection   Interrupt handling.   CPU now is in interrupt context in GIC interrupt handler. From gic_handle_irq() it calls handle_domain_irq() , which in turn calls generic_handle_irq() . See Documentation/gpio/driver.txt for details. Now we are in SoC's GPIO controller IRQ handler. SoC's GPIO driver also calls generic_handle_irq() to run handler, which is set for each particular pin. See for example how it's done in omap_gpio_irq_handler() . Now we are in PCA9555PW IRQ handler. PCA9555PW IRQ handler calls handle_nested_irq() . Finally, gpio_keys_gpio_isr() is called.      The following steps allow you to enable rgb led's and push buttons on 8MIC-RPI-MX8 board with i.MX 8M Mini Applications Processor Evaluation Kit (EVKB). You have to use a led driver and change the device tree. On the Host. Cloning the Linux kernel repository.   Clone the i.MX Linux Kernel repo to the home directory. cd ~ git clone https://source.codeaurora.org/external/imx/linux-imx This guide will use the following commit which corresponds to Kernel 5.10.35-2.0. cd linux-imx/ git checkout -b RGB ef3f2cfc6010 Patching the device tree.   Download the "0001-Enable-RGB-LED-s-and-push-buttons-on-8MIC-RPI-MX8-bo.patch" file attached to this post and copy it into linux-imx directory, then apply the patch. cp 0001-Enable-RGB-LED-s-and-push-buttons-on-8MIC-RPI-MX8-bo.patch ~/linux-imx/ cd ~/linux-imx/ patch < 0001-Enable-RGB-LED-s-and-push-buttons-on-8MIC-RPI-MX8-bo.patch When prompted, select the file to patch: File to patch: arch/arm64/boot/dts/freescale/imx8mm-evk-8mic-revE.dts patching file arch/arm64/boot/dts/freescale/imx8mm-evk-8mic-revE.dts Then setup your toolchain, for example: source /opt/fsl-imx-wayland/5.10-hardknott/environment-setup-cortexa53-crypto-poky-linux Generate config file. make imx_v8_defconfig Compile the device tree. make freescale/imx8mm-evk-8mic-revE.dtb Copy the .dtb file to the EVK, for example with scp: scp imx8mm-evk-8mic-revE.dtb root@<EVK_IP>:/home/root Alternatively, you may copy the .dtb file directly to the FAT32 partition where the Kernel and Device Tree files are located. Compiling the Led driver.   Obtain the leds-pca995x.h file in the next site: https://github.com/TechNexion/linux-tn-imx/blob/tn-imx_5.4.70_2.3.0-stable/include/linux/platform_data/leds-pca995x.h  Copy it into the next path: cp leds-pca995x.h ~/linux-imx/include/linux Create a new directory. mkdir ~/linux-imx/PCA9955 Create a makefile. cd ~/linux-imx/PCA9955 vim Makefile   KERNEL_ROOT?=~/linux-imx obj-m += leds-pca995x.o all: make -C $(KERNEL_ROOT) M=$(PWD) modules clean: make -C $(KERNEL_ROOT) M=$(PWD) clean   Press the key "Esc" and then: :wq Obtain the leds-pca995x.c file in the next site: https://github.com/TechNexion/linux-tn-imx/blob/tn-imx_5.4.70_2.3.0-stable/drivers/leds/leds-pca995x.c Copy it into the next path: cp leds-pca995x.c ~/linux-imx/PCA9955 Obtain 0001-PCA9955BTW.patch file and copy it into the next path: cp 0001-PCA9955BTW.patch ~/linux-imx/PCA9955 Apply the patch. patch < 0001-PCA9955BTW.patch Then setup your toolchain, for example: source /opt/fsl-imx-wayland/5.10-hardknott/environment-setup-cortexa53-crypto-poky-linux Generate .ko file. cd ~/linux-imx/PCA9955 make all Copy the .ko file to the EVK, for example with scp: scp leds-pca995x.ko root@192.168.100.105:/home/root NOTE: The linux version of .ko file must be the same as EVK. On the EVK. Switching the device tree.   To copy the updated device tree to the corresponding partition, first create a directory. mkdir Partition_1 Mount the partition one. mount /dev/mmcblk1p1 Partition_1/ Copy or move the device tree into partition one. cp imx8mm-evk-8mic-revE.dtb Partition_1/ Reboot the board. reboot Stop on u-boot and modify the .dtb file to use the device tree for 8mic board. u-boot=> editenv fdtfile edit: imx8mm-evk-8mic-revE.dtb u-boot=> saveenv Saving Environment to MMC... Writing to MMC(1)... OK u-boot=> boot Installing a led driver.   Execute the following command to load the led driver into the kernel. insmod leds-pca995x.ko And you will see something like: [ 249.359103] leds_pca995x: loading out-of-tree module taints kernel. [ 249.366864] ALL [ 249.368740] ALL 0 [ 249.370667] ALL 1 [ 249.372609] ALL 2 [ 249.374536] ALL 2 [ 249.376475] ALL 2 [ 249.378401] ALL 2 [ 249.380338] ALL 2 [ 249.382264] ALL 2 [ 249.384202] ALL 2 [ 249.386127] ALL 2 [ 249.388063] ALL 2 [ 249.389989] ALL 2 [ 249.391913] ALL 2 [ 249.393847] ALL 2 [ 249.395774] ALL 2 [ 249.397709] ALL 2 [ 249.399635] ALL 2 [ 249.401568] ALL 2 [ 249.403496] ALL 3 Turning on a Led.   If you changed the device tree, you can turn on a led with the following command: echo 250 > /sys/class/leds/pca995x\:blue0/brightness To turn off a led: echo 0 > /sys/class/leds/pca995x\:blue0/brightness The red, blue and green leds can be turned on at different intensities provided. Testing the push buttons.   If you changed the device tree, you can test the push buttons with the following command: evtest Select the correct number: No device specified, trying to scan all of /dev/input/event* Available devices: /dev/input/event0: 30370000.snvs:snvs-powerkey /dev/input/event1: sw_keys /dev/input/event2: gpio_ir_recv Select the device event number [0-2]: 1 And you will see: Input driver version is 1.0.1 Input device ID: bus 0x19 vendor 0x1 product 0x1 version 0x100 Input device name: "sw_keys" Supported events: Event type 0 (EV_SYN) Event type 1 (EV_KEY) Event code 67 (KEY_F9) Event code 113 (KEY_MUTE) Event code 114 (KEY_VOLUMEDOWN) Event code 115 (KEY_VOLUMEUP) Properties: Testing ... (interrupt to exit) Event: time 1642457988.1642457988, type 1 (EV_KEY), code 114 (KEY_VOLUMEDOWN), value 1 Event: time 1642457988.1642457988, -------------- SYN_REPORT ------------ Event: time 1642457988.1642457988, type 1 (EV_KEY), code 114 (KEY_VOLUMEDOWN), value 0 Event: time 1642457988.1642457988, -------------- SYN_REPORT ------------

The Yocto Project is open-source, so anyone can contribute. No matter what your contribution is (bug fixing or new metadata), contributions are sent through patches to a community list. Many eyes will look into your patch and at some point it is either rejected or accepted. Follow these steps to contribute: Make sure you have previously configured your personal info $ git config --global user.name "Your Name Here" $ git config --global user.email "your_email@example.com" Subscribed to the Freescale Yocto Project Mailing List Download `master` branches fsl-community-bsp $ repo init \   -u https://github.com/Freescale/fsl-community-bsp-platform \   -b master Update fsl-community-bsp $ repo sync Create local branches so your work is *not* done on master fsl-community-bsp $ repo start <branch name> --all Where `<branch name>` is any name you want to give to your local branch (e.g. `fix_uboot_recipe`, `new_gstreamer_recipe`, etc.) Make your changes in any Freescale related folder (e.g. sources/meta-fsl-arm). In case you modified a recipe (.bb) or include (.inc) file, do not forget to *bump* (increase the value by one) either the `PR` or `INC_PR` value Commit your changes using `git`. In this example we assume your change is on `meta-fsl-arm` folder sources/meta-fsl-arm $ git add <file 1> <file 2> sources/meta-fsl-arm $ git commit On the commit's log, the title must start with the filename change or introduced, then a brief description of the patch's goal, following with a long description. Make sure you follow the standards (type ` git log --pretty=oneline` to see previous commits) Create a patch sources/meta-fsl-arm $ git format-patch -s  --subject-prefix='<meta-fsl-arm][PATCH' -1 Where the last parameter (`-1`) indicate to patch last commit. In case you want to create patches for older commits, just indicate the correct index. If your patch is done in other folder, just make sure you change the `--subject-prefix` value. Send your patch or patches with git send-email --to meta-freescale@yoctoproject.org <patch> where `<patch>` is the file created by `git format-patch`. Keep track of patch's responses on the mailing list. In case you need to rework your patch, repeat the steps but this time the patch's subject changes to `--subject-prefix='<meta-fsl-*][PATCH v2'` Once your patch has been approved, you can delete your working branches fsl-community-bsp $ repo abandon <branch name>

When flashing a Linux System on a SD card using the script mk_mx28_sd on a Ubuntu 12.04 host, one needs to modify it so partitions are created correctly.  Just follow these steps on the console: $ cd $SDK/L2.6.35_10.12.01_SDK_scripts $ cat > first_partition_sector.patch << EOF diff -Naur a/mk_mx28_sd b/mk_mx28_sd --- a/mk_mx28_sd        2010-10-06 09:47:42.000000000 -0500 +++ b/mk_mx28_sd        2012-11-30 13:38:34.508199154 -0600 @@ -178,7 +178,7 @@ n p 1 -1 +2048 +32M t b EOF $ patch -p1 < first_partition_sector.patch then, you can run the mk_mx28_sd command again with the device as parameter                $ cd $LIB $ export PATH=$PATH:$SDK/L2.6.35_10.12.01_SDK_scripts $ mk_mx28_sd /dev/$SDX

This doc show how to use i.MX8QXP Display Controller GammaCor unit to tune gamma. HW: i.MX8QXP MEK board, HDMI monitor SW: i.MX Linux 4.14.98_2.2.0 BSP release, patch in this doc 1.Introduce gamma The gamma, gamma correction, gamma encoding, gamma compression , these words all related one kind operation , see wiki page of it: The device used for image capture/print/display follow this power-law. For example the camera captured image , to view this image on display device as good as original captured image : gamma encoding when camera saved sensor data to image file,  and  gamma decoding when that image file display on your PC LCD monitor. That is : 2. i.MX8QXP Display Controller Gamma Correction Unit The Gamma Correction unit position is located between Frame Gen unit and TCon unit.   More detail see below contents from i.MX8QXP RM: So GammaCor unit could be used as adjust display gamma , or brightness or contrast. To used it, need follow the steps at RM 15.9.2.4.4.8.3.   Something need to note: You need program 33 sample point value into the register, these sample point value range is from 0 to 1023. Note, first write is start sample point value , then the other is delta value: current sample point minus previous sample point value. You can use GammaCor unit on any channel of R/G/B. If you use normalized function f(x), the following formula should be used to clut[i = 0..32] = round( f(i * 32 / 1023) * 1023) 3. i.MX8QXP Linux device driver patch and test code Apply attached  patch 8qxp_dpu_gammacor_4.14.98_2.2.0.diff on Linux kernel. In the kernel patch, function dpu_gammacor_update, I choose not calculate delta value between each sample pint , let user space application calculate delta value and passed to kernel. Apply 8qxp-dpu-gammacor-modetst.diff on libdrm-imx, to get test application which is based on modetest.  Test app will read one greyscale image file 720P.rgb, put it under same folder of test application , calculate sample point value by pow function  , and calling drmModeCrtcSetGamma to pass related value to kernel,  next loop will change sample point value, and will see that greyscale image will changed on HDMI monitor. After system boot up, run below cmd to check result of test application systemctl stop weston ./gamma_show_rgba.out -P 29@32:1280x720@AB24 Reference: a>https://www.nxp.com/webapp/Download?colCode=IMX8DQXPRM b>https://www.nxp.com/webapp/Download?colCode=L4.14.98_2.2.0_MX8QXP&appType=license c> https://source.codeaurora.org/external/imx/libdrm-imx/ d> https://en.wikipedia.org/wiki/Gamma_correction

  Platform: i.MX8MP EVK , L6.1.22-2.0.0 LT9211 is a chip that can realize the conversion of MIPI DSI signals to LVDS signals. This patch is based on this mainline driver:https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/drivers/gpu/drm/bridge/lontium-lt9211.c Keypoint Move lt9211_host_attach function to lt9211_attach to skip bridge attach error.  

OpenGL OpenGL is the premier environment for developing portable, interactive 2D and 3D graphics applications. Since its introduction in 1992, OpenGL has become the industry's most widely used and supported 2D and 3D graphics application programming interface (API), bringing thousands of applications to a wide variety of computer platforms. OpenGL fosters innovation and speeds application development by incorporating a broad set of rendering, texture mapping, special effects, and other powerful visualization functions. Developers can leverage the power of OpenGL across all popular desktop and workstation platforms, ensuring wide application deployment. Source: http://www.opengl.org/about/overview/ On i.MX processors, OpenGL takes the advantage of GPU (Graphics Processing Unit) block to improve 3D performance. Installing and running Demos Get more information on how to install and run demos using OpenGL on i.MX31 on this application note: AN3723 - Using OpenGL Applications on the i.MX31 ADS Board - http://www.freescale.com/files/dsp/doc/app_note/AN3723.pdf?fsrch=1 Develop a simple OpenGL ES 2.0 application under Linux This tutorial shows how to develop a simple OpenGL ES 2.0 application with LTIB and an i.MX51 EVK board. This tutorial can be adapted to i.MX53 that share the same 3D GPU core (Z430) and API (OpenGL ES 2.0).

The Linux L4.1.15_2.0.3 Patch for i.MX 6ULL@900MHz Release is now available on www.nxp.com. BSP Updates and Releases -> Linux -> Linux 4.1.15_2.0.3 Patch.   Files available: # Name Description 1 L4.1.15_2.0.3_6ULL_patch_images.tar.gz i.MX 6ULL-EVK@900MHz Linux Binary Demo Files   Information of release, see: README: http://git.freescale.com/git/cgit.cgi/imx/fsl-arm-yocto-bsp.git/tree/README?h=imx-4.1-krogoth ChangeLog: http://git.freescale.com/git/cgit.cgi/imx/fsl-arm-yocto-bsp.git/tree/ChangeLog?h=imx-4.1-krogoth

The vbs file is a script file in mfgtool. In fsl android lollipop consolidate and later MFGTOOL version, You just need add a new vbs item for new board and have not need to change the ucl2.xml. The below is the example struct. Set wshShell = CreateObject("WScript.shell") wshShell.run "mfgtool2.exe -c ""linux"" -l ""SDCard-Android"" -s ""board=sabresd"" -s ""folder=sabresd"" -s ""soc=6dl"" -s ""mmc=2"" -s ""data_type=-f2fs""" Set wshShell = Nothing Explain for each option: -l: storage type      There three type for android: Nand-Android\eMMC-Android\SDCard-Android -s: extend variable      board: It is used to download uboot and dts in init system.      folder: there are three type: sabresd sabreauto evk                the android image is located in: files/android/%folder%/      soc: Used to define android image name. types: 6q, 6dl, 6sx, 6sl.      mmc: define the storage idex.      data_type: if the type of data partition is f2fs, need define data_type=-f2fs      ldo: if the board is 1.2G, need to define it to -ldo      plus: if the board is 6qp, need too define it to p

If you are a Windows user and don't want to install Linux on your machine, VMware is a virtual machine used to install Linux under Windows. It's a good way to start with Linux (if you're unfamiliar with it) and also start your i.MX development. Installing VMWare - VMWare Workstation [VMWare Workstation (Click here to go to Download page)] VMWare Workstation is available in commercial and trial versions. With Workstation is possible to create your own installation image—installing a new operating system as you would install it in a new machine. - VMWare Player [VMWare Player (Click here to go to Download page)] VMWare Player is available in a free version. With Player is only possible to run images previously made. - VMWare Images at ThoughtPolice site [ThoughtPolice site (Click here to go to Download page)] This site has many ready VMWare images from many Linux distributions. It just needs to be downloaded, unziped and it's ready to be used with VMware. Workstation or Player.

NFS Network File System (NFS) is a network file system protocol originally developed by Sun Microsystems in 1984, allowing a user on a client computer to access files over a network as easily as if the network devices were attached to its local disks. The use of NFS makes the development work of user space applications easy and fast since all target root file system is located into host (PC) where the applications can be developed and crosscompiled to target system. The target system will use this file system located on host as if it is located on target. NFS service will be used to transfer the root file system from host to target. NFS resources are listed below: All Boards Deploy NFS All Boards NFS on Fedora NFS on Fedora All Boards NFS on Slackware NFS on Slackware All Boards NFS on Ubuntu NFS on Ubuntu

When to enable CONFIG_DEBUG_LL, choose the debug port and then CONFIG_EARLY_PRINTK on i.MX6, system will hang. There is no error information there as below, Uncompressing Linux... done, booting the kernel. Booting Linux on physical CPU 0x0 Initializing cgroup subsys cpu Initializing cgroup subsys cpuacct Linux version 4.1.15-00001-gd582989-dirty (jay@jay-ubuntu) (gcc version 4.9 20 150123 (prerelease) (GCC) ) #10 SMP PREEMPT Mon Jul 17 15:08:55 CST 2017 CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c53c7d CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache Machine model: Freescale i.MX6 Quad SABRE Smart Device Board bootconsole [earlycon0] enabled cma: Reserved 448 MiB at 0x2a000000 Memory policy: Data cache writealloc -------------- hang -----------------‍‍‍‍‍‍‍‍‍‍‍‍‍ The patch fix it on android n7.1.1_1.0.0, kernel: 4.1.15.

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

The Linux L4.9.51 and SDKv2.3 for i.MX 8MQuad(mScale850D) RFP(GA) release files are now available. Linux on IMX_SW web page, Overview -> BSP Updates and Releases ->Linux L4.9.51 for i.MX 8MQuad GA. SDK on https://mcuxpresso.nxp.com/ web page.   Files available: Linux: # Name Description 1 fsl-yocto-L4.9.51_mx8mq-ga.tar.gz L4.9.51 i.MX 8MQuad GA Linux BSP Documentation. Includes Release Notes, User Guide. 2 L4.9.51-ga_images_mx8mq.tar.gz Linux Binary Demo files for i.MX 8MQuad EVK 3 L4.9.51_8mq-ga_mfg-tools.tar.gz Manufacturing Toolkit for Linux L4.9.51 i.MX8MQuad GA 4 L4.9.51_8mq-ga_gpu-tools.tar.gz VivanteVTK file for L4.9.51 i.MX8MQuad GA 5 imx-aacpcodec-4.3.4.tar.gz AAC Plus Codec for L4.9.51 of iMX 8MQuad GA   SDK:   On https://mcuxpresso.nxp.com/, click the Select Development Board to customize the SDK based on your configuration then download the SDK package. CMSIS pack is also supported.   Target board: i.MX 8MQuad EVK   What’s New/Features: Please consult the Release Notes.   Known issues For known issues and more details please consult the Release Notes.   More information on changes of Yocto, see: README: https://source.codeaurora.org/external/imx/imx-manifest/tree/README?h=imx-linux-morty ChangeLog: https://source.codeaurora.org/external/imx/imx-manifest/tree/ChangeLog?h=imx-linux-morty  

BSP: L5.15.5_1.0.0 Platform: i.MX8MPlus EVK Background   The function lpddr4_mr_read in BSP always return zero and this casue the customer can't use it to read MR registers in DRAM. This is a simple demo for reading MR registers. Patch Code   diff --git a/arch/arm/include/asm/arch-imx8m/ddr.h b/arch/arm/include/asm/arch-imx8m/ddr.h index 0f1e832c03..fd68996a23 100644 --- a/arch/arm/include/asm/arch-imx8m/ddr.h +++ b/arch/arm/include/asm/arch-imx8m/ddr.h @@ -721,6 +721,8 @@ int wait_ddrphy_training_complete(void); void ddrphy_init_set_dfi_clk(unsigned int drate); void ddrphy_init_read_msg_block(enum fw_type type); +unsigned int lpddr4_mr_read(unsigned int mr_rank, unsigned int mr_addr); + void update_umctl2_rank_space_setting(unsigned int pstat_num); void get_trained_CDD(unsigned int fsp); diff --git a/board/freescale/imx8mp_evk/spl.c b/board/freescale/imx8mp_evk/spl.c index 33bbbc09ac..85e40ffbbe 100644 --- a/board/freescale/imx8mp_evk/spl.c +++ b/board/freescale/imx8mp_evk/spl.c @@ -150,6 +150,40 @@ int board_fit_config_name_match(const char *name) return 0; } #endif +void lpddr4_get_info() +{ + int i = 0, attempts = 5; + + unsigned int ddr_info = 0; + unsigned int regs[] = { 5, 6, 7, 8 }; + + for(i = 0; i < ARRAY_SIZE(regs); i++){ + unsigned int data = 0; + data = lpddr4_mr_read(0xF,regs[i]); + ddr_info <<= 8; + ddr_info += (data & 0xFF); + switch (i) + { + case 0: + printf("DRAM INFO : Manufacturer ID = 0x%x",ddr_info); + if(ddr_info & 0Xff) + printf(", Micron\n"); + break; + case 1: + printf("DRAM INFO : Revision ID1 = 0x%x\n",ddr_info); + break; + case 2: + printf("DRAM INFO : Revision ID2 = 0x%x\n",ddr_info); + break; + case 3: + printf("DRAM INFO : I/O Width and Density = 0x%x\n",ddr_info); + break; + default: + break; + } + } + +} void board_init_f(ulong dummy) { @@ -187,6 +221,8 @@ void board_init_f(ulong dummy) /* DDR initialization */ spl_dram_init(); + + lpddr4_get_info(); board_init_r(NULL, 0); } diff --git a/drivers/ddr/imx/imx8m/ddrphy_utils.c b/drivers/ddr/imx/imx8m/ddrphy_utils.c index 326b92d784..f45eeaf552 100644 --- a/drivers/ddr/imx/imx8m/ddrphy_utils.c +++ b/drivers/ddr/imx/imx8m/ddrphy_utils.c @@ -194,8 +194,15 @@ unsigned int lpddr4_mr_read(unsigned int mr_rank, unsigned int mr_addr) tmp = reg32_read(DRC_PERF_MON_MRR0_DAT(0)); } while ((tmp & 0x8) == 0); tmp = reg32_read(DRC_PERF_MON_MRR1_DAT(0)); - tmp = tmp & 0xff; reg32_write(DRC_PERF_MON_MRR0_DAT(0), 0x4); + + while (tmp) { //try to find a significant byte in the word + if (tmp & 0xff) { + tmp &= 0xff; + break; + } + tmp >>= 8; + } return tmp; }     Test Result  

The i.MX 8QuadXPlus Multisensory Enablement Kit (MEK) is a NXP development platform based on Cortex A-35 + Cortex-M4 cores. Built with high-level integration to support graphics, video, image processing, audio, and voice functions, the i.MX 8X processor family is ideal for safety-certifiable and efficient performance requirements. This tutorial shows how to enable the Cortex-M4 using the MCUXpresso SDK package and loading the binary from the network. NOTE: It is also possible to load the Cortex-M4 image from the SCFW using the imx-mkimage utility. But now we are going to focus on MCUXpresso. Setting up the machine   Install cmake on the host machine: $ sudo apt-get install cmake Download the armgcc toolchain and export the location as ARMGCC_DIR: $ export ARMGCC_DIR=<your_path_to_arm_gcc>/gcc-arm-none-eabi-9-2020q2/ NOTE: The ARMGCC_DIR variable needs to be exported on the terminal used for compilation. To setup the TFTP server on the host machine: Configuring your Host PC for TFTPPermalink   The first step is to install all the prerequisite packages for TFTP: $ sudo apt-get install xinetd tftpd tftp Create a TFTP folder in your desired location with root owner and the “rwx” permission for all users: $ sudo mkdir /tftpboot $ sudo chmod –R 777 /tftpboot $ sudo chown –R root /tftpboot Create a configuration file for the TFTP with the following content. (The server_args parameter must match with the folder created above) $ cat /etc/xinetd.d/tftp service tftp { protocol = udp port = 69 socket_type = dgram wait = yes user = root server = /usr/sbin/in.tftpd server_args = -s /tftpboot disable = no } Restart the xinetd service: $ sudo /etc/init.d/xinetd restart You can place any file at the TFTP folder and load it through U-Boot, you can also create symbolic links from your building directory avoiding to copy and paste your zImage and dtb files every time. Configuring your Host PC for NFSPermalink   Install all the needed packages for NFS: $ sudo apt-get install nfs-kernel-server Create a folder for placing your rootfs: $ mkdir /tftpboot/rfs Add the following line in the end of your /etc/exports file: /tftpboot/rfs *(rw,no_root_squash,no_subtree_check) Restart the NFS service: $ sudo service nfs-kernel-server restart Place your rootfs or create a symbolic link for the NFS folder.    Downloading the SDK Download the MCUXpresso following these steps: Click on “Select Development Board”; Select MEK-MIMX8QX under “Select a Device, Board, or Kit” and click on “Build MCUXpresso SDK” on the right; Select “Host OS” as Linux and “Toolchain/IDE” as GCC ARM Embedded; Add “FreeRTOS” and all the wanted Middleware and hit “Request Build”; Wait for the SDK to build and download the package. Building the image All demos and code examples available on the SDK package are located in the directory <<SDK_dir>>/boards/mekmimx8qx/. This tutorial shows how to build and flash the hello_world demo but similar procedures can be applied for any example (demo, driver, multicore, etc) on the SDK. To build the demo, enter the armgcc folder under the demo directory and make sure that the ARMGCC_DIR variable is set correctly. $ cd ~/SDK_2.3.0_MEK-MIMX8QX/boards/mekmimx8qx/demo_apps/hello_world/armgcc $ export ARMGCC_DIR=<your_path_to_arm_gcc>/gcc-arm-none-eabi-9-2020q2/ Run the build_release.sh script to build the code. $ ./build_release.sh NOTE: If needed, give the script execution permission by running chmod +x build_release.sh. This generates the M4 binary (hello_world.bin) under the release folder. Copy this image to the /tftpboot/ directory on the host PC. NOTE: This procedure shows how to build the M4 image that runs on TCM. To run the image from DDR, use the build_ddr_release.sh script to build the binary under the ddr_release folder. Flashing the image Open two serial consoles, one for /dev/ttyUSB0 for Cortex-A35 to boot Linux, and one for /dev/ttyUSB1 for Cortex-M4 to boot the SDK image. On the A35 console, with a SD Card with U-Boot, stop the booting process and enter the following commands to load the M4 binary to TCM: => dhcp => setenv serverip <ip_from_host_pc> => tftp 0x88000000 hello_world.bin => dcache flush => bootaux 0x88000000 Then the M4 core will load the image to the /dev/ttyUSB1 console.    

Some i.MX25 customers reported an issue for the GPT timer, when using 120MHz (240MHz UPLL divided 2) clock source as the GPT per_clk, the timer will not be increased all the time in free-run mode. If using 66.5MHz IPG clock and 133MHz PER clock as the clock source, there are no such issue. There are 4 test cases in the attached test code. Case 0: in CCM_MCR, set bit 5 as 0 for 133MHz HCLK as the gpt_per_clk source;  in GPT_CR bit[8:6], set 0b001 ipg_clk (66.5MHz). There is no issue, the GPT counter is fixed at 4 between old_cnt and new_cnt. Case 1: in CCM_MCR, set bit 5 as 0 for 133MHz HCLK as the gpt_per_clk source;  in GPT_CR bit[8:6], set 0b010 ipg_clk_highfreq (133MHz). There is no issue, the GPT counter is fixed at 8 between old_cnt and new_cnt. Case 2: in CCM_MCR, set bit 5 as 1 for 240MHz UPLL divided by 2 as the gpt_per_clk source;  in GPT_CR bit[8:6], set 0b001 ipg_clk (60MHz). There is no issue, the GPT counter is fixed at 4 between old_cnt and new_cnt. Case 3: in CCM_MCR, set bit 5 as 0 for 240MHz UPLL divided by 2 as the gpt_per_clk source;  in GPT_CR bit[8:6], set 0b010 ipg_clk_highfreq (120MHz). There is issue, the GPT counter is not a fixed value between old_cnt and new_cnt, and sometimes it will be negative. Count 9874: 4 old_cnt: 0x188849dc new_cnt: 0x188849e0 Count 9877: 12 old_cnt: 0x18918400 new_cnt: 0x1891840c Count 9915: 4 old_cnt: 0x189aea90 new_cnt: 0x189aea94 Count 9937: -12 old_cnt: 0x18a42458 new_cnt: 0x18a4244c Count 9967: 4 old_cnt: 0x18adb17c new_cnt: 0x18adb180 In fact, it is not an issue, when using UPLL as the GPT clock source, the maxim frequency should be 60MHz. That's why all other three test case is OK and it only failed on this case.

Using a USB Touchscreen on Ubuntu   This example uses a XENARC 706TSA monitor http://www.xenarc.com/product/706tsa.html To use a USB touchscreen on i.MX51 EVK, disable all touchscreen drivers on menuconfig and build the kernel: Device Drivers  --->        Input device support  --->        [ ]   Touchscreens  ---> Download xserver-xorg-input-evtouch (0.8.8-ubuntu3 version) from http://launchpadlibrarian.net/24760784/xserver-xorg-input-evtouch_0.8.8-0ubuntu3_armel.deb. X crash is found if using latest 0.8.8-ubuntu6.1 version. For the details. See https://bugs.launchpad.net/ubuntu/+source/xf86-inputevtouch/+bug/511491 On MX51 EVK board, run “sudo dpkg –i xserver-xorg-input-evtouch_0.8.8-0ubuntu3_armel.deb” to install debian package. Add fdi file by "sudo vi ./usr/share/hal/fdi/policy/20thirdparty/50-eGalax.fdi": <?xml version="1.0" encoding="UTF-8"?> <deviceinfo version="0.2">    <device>       <match key="info.product" contains="eGalax">          <match key="info.capabilities" contains="input">             <merge key="input.x11_driver" type="string">evtouch</merge>             <merge key="input.x11_options.minx" type="string">130</merge>             <merge key="input.x11_options.miny" type="string">197</merge>             <merge key="input.x11_options.maxx" type="string">3945</merge>             <merge key="input.x11_options.maxy" type="string">3894</merge>             <merge key="input.x11_options.Rotate" type="string">CCW</merge>             <merge key="input.x11_options.Swapy" type="string">true</merge>             <merge key="input.x11_options.taptimer" type="string">30</merge>             <merge key="input.x11_options.longtouchtimer" type="string">750</merge>             <merge key="input.x11_options.longtouched_action" type="string">click</merge>             <merge key="input.x11_options.longtouched_button" type="string">3</merge>             <merge key="input.x11_options.oneandhalftap_button" type="string">2</merge>             <merge key="input.x11_options.movelimit" type="string">10</merge>             <merge key="input.x11_options.touched_drag" type="string">1</merge>             <merge key="input.x11_options.maybetapped_action" type="string">click</merge>             <merge key="input.x11_options.maybetapped_button" type="string">1</merge>          </match>       </match>    </device> </deviceinfo> Save above configuration. Calibrating Calibration in made by clicking on System -> Administration -> Calibrate Touchscreen Follow the on screen instructions and reboot the system. Calibrating using Xinput Calibrator Xinput_calibrator is another option to calibrate touchscreen. It can be downloaded at: http://www.freedesktop.org/wiki/Software/xinput_calibrator On i.MX5x Ubuntu, unpack the source code: tar -xzvf xinput_calibrator-0.7.5.tar.gz Install xorg-dev, it's required to build xinput_calibrator sudo apt-get install xorg-dev Configure, build and install xinput_calibrator ./configure ./make ./make install Execute xinput_calibrator. A four-point calibration screen will be shown. Follow the instructions on screen and after complete xinput_calibrator will return the calibration parameters. Replace the given calibration parameters on file /usr/share/hal/fdi/policy/20thirdparty/50-eGalax.fdi and reboot the system.

This example uses the touchscreen that comes with i.MX51 EVK's parallel LCD Download xserver-xorg-input-evtouch (xserver-xorg-input-evtouch_0.8.8-3build1_armel.deb) from https://launchpad.net/ubuntu/lucid/armel/xserver-xorg-input-evtouch/0.8.8-3build1 On i.MX51 EVK board, run “sudo dpkg –i xserver-xorg-input-evtouch_0.8.8-3build1_armel.deb” to install debian package. Remove evdev config file: sudo rm /usr/lib/X11/xorg.conf.d/05-evdev.conf Change the content of 10-evtouch.conf to: sudo vi /usr/lib/X11/xorg.conf.d/10-evtouch.conf Section "InputClass"            Identifier "touchscreen catchall"            MatchIsTouchscreen "on"            Driver "evtouch"            Option "SwapY" "1"            Option "MinX" "32"            Option "MinY" "46"            Option "MaxX" "1001"            Option "MaxY" "967" EndSection   The MinX, MinY, MaxX and MaxY values can be changed to match the exact configuration of your touchscreen Save above configuration and reboot the system.

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