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Here we show how to generate a minimal root filesystem fairly quickly with BusyBox, for the i.MX6 sabre sd platform. This document assumes you are able to boot a Linux kernel on your platform already. See this post for details on how to do it. This implies you already have a "working" Linux development environment with some ARM cross-compilers at hand (e.g. Debian + Emdebian). busybox is so small that we will go for a ramdisk as our main root filesystem. Get busybox sources We will use git to fetch busybox sources:   $ git clone git://git.busybox.net/busybox This should create a busybox directory with all the latest sources. Note that for more stability you might want to checkout a release instead of the latest version; to do so, list the available release tags with e.g. git tag -l, and git checkout <the-desired-tag>. Compile Assuming your cross compiler is called e.g. arm-linux-gnueabihf-gcc, you can compile by doing:   $ cd busybox   $ export ARCH=arm   $ export CROSS_COMPILE=arm-linux-gnueabihf-   $ make defconfig   $ sed -i.orig 's/^#.*CONFIG_STATIC.*/CONFIG_STATIC=y/' .config   $ make   $ make install This should create an _install folder hierarchy containing binaries and links. Note that we force the build of a static binary with the sed command. Configure the root filesystem We need to add some more configuration into the _install folder before we can call it a minimal filesystem. Create some folders We need to create some mountpoints and folders:   $ mkdir _install/dev   $ mkdir _install/proc   $ mkdir _install/sys   $ mkdir -p _install/etc/init.d Add some configuration files and scripts We need to prepare the main init configuration file, _install/etc/inittab, with this contents:   ::sysinit:/etc/init.d/rcS   ::askfirst:/bin/sh   ::ctrlaltdel:/sbin/reboot   ::shutdown:/sbin/swapoff -a   ::shutdown:/bin/umount -a -r   ::restart:/sbin/init This is very close to the default behavior busybox init has with no inittab file. It just suppresses some warnings about missing tty. We need to add some more configuration to mount a few filesystems at boot for convenience. This is done with an _install/etc/fstab file containing:   proc     /proc proc     defaults 0 0   sysfs    /sys  sysfs    defaults 0 0   devtmpfs /dev  devtmpfs defaults 0 0 We also need to actually trigger the mount in the _install/etc/init.d/rcS script, which is called from the inittab. It should contain:   #!/bin/sh   mount -a And we need to make it executable:   $ chmod +x _install/etc/init.d/rcS Generate the ramdisk contents Now that we have adapted the root filesystem contents, we can generate a busybox ramdisk image for u-boot with the following commands:   $ (cd _install ; find |cpio -o -H newc |gzip -c > ../initramfs.cpio.gz)   $ mkimage -A arm -T ramdisk -d initramfs.cpio.gz uInitrd This results in a uInitrd file, suitable for u-boot. Prepare a boot script The default u-boot commands are not sufficient to boot our system, so we need to edit a boot.txt file with the following contents:   run loaduimage   run loadfdt   setenv rdaddr 0x13000000   fatload mmc ${mmcdev}:$mmcpart $rdaddr uInitrd   setenv bootargs console=${console},${baudrate} rdinit=/sbin/init   bootm $loadaddr $rdaddr $fdt_addr Then we generate a boot.scr script, which can be loaded by u-boot with:   $ mkimage -A arm -T script -d boot.txt boot.scr Put on SD card Assuming you have prepared your SD card with u-boot and Linux as explained in this post, you have a single FAT partition on your card with your kernel and dtb. Our boot script and ramdisk image should be copied alongside:   $ mount /dev/<your-sd-card-first-partition> /mnt   $ cp uInitrd boot.scr /mnt/   $ umount /mnt Your SD card first partition is typically something in /dev/sd<X>1 or /dev/mmcblk<X>p1. Note that you need write permissions on the SD card for the command to succeed, so you might need to su - as root, or use sudo, or do achmod a+w as root on the SD card device node to grant permissions to users. Boot! Your SD card is ready for booting. Insert it in the SD card slot of your i.MX6 sabre sd platform, connect to the USB to UART port with a serial terminal set to 115200 baud, no parity, 8bit data and power up the platform. Your busybox system should boot to a prompt:   ...   Freeing unused kernel memory: 292K (806d5000 - 8071e000)   Please press Enter to activate this console. After pressing enter you should have a functional busybox shell on the target. Enjoy! See also... For a more featured root filesystem you might want to try a Debian filesystem in a second SD card partition, as explained in this post, or generate your filesystem with Buildroot. If you plan to compile busybox often, you might want to use a C compiler cache; see this post.
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by b47504 Overview This document is intended to introduce debug tips about i.MX power management based on i.MX Android software. The following topics are involved in this document: How to debug suspend/resume issues How to do power optimization How to debug suspend/resume issues General method: Capture more PM  debug message Enable PM debug system to get more info about PM in kernel and debug interface Power management options  ---> [*] Power Management Debug Support                                     [*]   Extra PM attributes in sysfs for low-level debugging/testing Enable wakelock debug_mask to capture more message about wakelock root@android:/ # echo 15 > /sys/module/wakelock/parameters/debug_mask root@android:/ # echo 15 > /sys/module/userwakelock/parameters/debug_mask Enable earlysuspend debug_mask to capture more message about early suspend and late resume. root@sabresd_6dq:/ # echo 15 > /sys/module/earlysuspend/parameters/debug_mask Add no_console_suspend=1 to the boot option for kernel This makes the system print more useful info before entry in suspend Eg: --- a/sabresd_6dq/BoardConfig.mk +++ b/sabresd_6dq/BoardConfig.mk -BOARD_KERNEL_CMDLINE := console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,bpp=32 video=mxcfb1:off video=mxcfb2:off fbmem=10M fb0base=0x27b00000 vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale +BOARD_KERNEL_CMDLINE := console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,bpp=32 video=mxcfb1:off video=mxcfb2:off fbmem=10M fb0base=0x27b00000 vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale no_console_suspend=1 System cannot enter suspend mode Check below setting items have been disabled: §  Whether the usb cable has been removed(usb gadget will hold a wake lock) §  Setting->Display->Sleep, check whether the inactivity timeout period setting is longer than your expected time. §  Setting->System->Developer options->stay awake(stay awake not be set), check whether the option is disabled Check if all wake locks have been released(You can see which wake lock is held, and then debug into the specific module): root@sabresd_6dq:/ # cat /sys/power/wake_lock System could not resume from suspend/System crash when resume or suspend Check the PMIC_STBY_REQ signal. System use PMIC_STBY_REQ signal to notify power management IC to change voltage from standby voltage to functional voltage and vice versa. In general, pmic_stby_req pin is connected to pmic standby pin. So measure the pin to check whether the  de-assert signal is triggered. If the signal is not triggered, we may consider whether wake-up sources are correctly setup. If the signal is triggered, we may double-check whether the pmic supply power normally. And not limited to the two points, we should also double-check everything we doubt according to the system log and hardware measured waves.  Using Trace32 or ICE to locate the problem. Please view trace32 website to get more details. Track from mx6_suspend_enter in arch/arm/mach-mx6 .                Track "state" value and try to map to different the low power mode via function mxc_cpu_lp_set.                Check "mx6_suspend.S" which conduct the detailed operations in suspend: "MEM" is mapped to "dormant" mode. So goto "dormant" symbol and try to dump different operations to narrow down suspend/resume failure If this failure maybe related to DDR operation, try to dummy DDR IO relative low power operation. Using ram console to dump kernel log after reboot. Ram console will keep one kernel log copy into one certain memory space. You can use the following command to check last time kernel log, if memory power was not cut off during the reboot process. Eg(if it is the first time boot, you cannot find the /proc/last_kmsg file): root@sabresd_6dq:/ # cat /proc/last_kmsg Kernel resume back from suspend but android not This is usually introduced by the wrong key layout file Use getevent/sendevent tool to get power key scan code #getevent  Correct the Keylayout file    system/usr/keylayout/****.kl Correct the scandcode with your power key report value to Match the POWE key Suspend/Resume consume too much time: We can print the specific module name and time consume details, if the module's suspend/resume time consume more than the threshold parameter by read/write /sys/power/device_suspend_time_threshold file. By default, the parameter is setup to 0, via disabled the function. We can enable it by the following command: Eg: root@android:/ # echo 10  > /sys/power/device_suspend_time_threshold This command means that if the module's suspend/resume time consume more than 10 us, the system will print the module's detail out. If you want to know the more details how to implement it on kernel, please check kernel/power/main.c Notes: Can use the shell command to enter different system level low power modes for debug (For more details: you can check Linux_6DQ_RM.pdf): #echo mem > /sys/power/state #echo standby > /sys/power/state How to do power optimization Runtime Mode Check whether CPUFreq and  Bus_freq scale are enabled root@android:/ # cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor root@android:/ # cat /sys/devices/platform/imx_busfreq.0/enable More details about this, please refer to "Documentation/cpu-freq/ governors.txt” . Check whether the system bus is working on your expected frequency. For MX6Q: root@android:/ #  cat /sys/kernel/debug/clock/osc_clk/pll2_528_bus_main_clk/periph_clk/mmdc_ch0_axi_clk/rate Check CPU Loading and Interrupt(cat /proc/interrupts)                root@android:/ #  cat /proc/interrupts                Through this command you can check whether some module will trigger interrupt frequently.  And consider that whether we have some chances to reduce the interrupt count. Check clock tree carefully to see which clocks are not gated off  but no any modules need them. root@android:/ # powerdebug -d -c Reduce GPU frequency.GPU also offered interface to modify the frequency. According to your own product, you can reduce the gpu frequency. Default gpu3DMaxClock is set to 64 in init.rc file, we can tuning a suitable value by ourselves. diff --git a/imx6/etc/init.rc b/imx6/etc/init.rc index 8c420b5..eb11ffe 100755 --- a/imx6/etc/init.rc +++ b/imx6/etc/init.rc @@ -397,6 +397,9 @@ on boot #  Set GPU 3D minimum clock to 3/64     write /sys/module/galcore/parameters/gpu3DMinClock 3 +#  Set GPU 3D maximum clock to 64/64 +   write /sys/module/galcore/parameters/gpu3DMaxClock 64 + Suspend Mode Check whether all devices enter suspend mode or low power mode: Add debug message into devices drivers to check whether all devices driver suspend interface are called Use oscilloscope to measure the related signal (depend on specific device datasheet and custom hw design) to check whether every device enter low power mode Remove devices from the board(or rmmod the device driver) , and do hardware rework to exclude some hardware module if needed. Then we can figure out which module introduced the high consumption, and debug into the specific module. Add debug message in device drivers which may lead high power consumption, catch the waveform from these modules which may impact the high power consumption Check whether DDR enter in self-refresh mode(Please check the DDR datasheet to figure out which pin indicate self-refresh state, and check it with oscilloscope) Config GPIO PADs as output zero or input mode (depending to HW design) Cut off LDOs/DCDCs which no modules need (depending to HW design) Check all PLLs will cut off, just 32KHZ sleep clock living
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This is a detailed programming aid for the registers associated with i.MX 8MNano (m815S) DDR initialization.  For more details, refer to the main mScale DDR tools page: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-8M-Family-DDR-Tool-Release/ta-p/1104467 Please note that this page is only intended to store the RPA spreadsheets. For questions, please create a new community thread.
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Hello there. Here is a good way to use U-boot in an efficient way with custom scripts. The bootscript is an script that is automatically executed when the boot loader starts, and before the OS auto boot process. The bootscript allows the user to execute a set of predefined U-Boot commands automatically before proceeding with normal OS boot. This is especially useful for production environments and targets which don’t have an available serial port for showing the U-Boot monitor. This information can be find in U-Boot Reference Manual.   I will take the example load a binary file in CORTEX M4 of IMX8MM-EVK. In my case, I have the binary file in MMC 2:1 called gpio.bin and I will skip those steps because that is not the goal.   First, you need the u-boot-tools installed in your Linux machine: sudo apt install u-boot-tools   That package provide to us the tool mkimage to convert a text file (.src, .txt) file to a bootscript file for U-Boot.   Now, create your custom script, in this case a simple script for load binary file in Cortex M4: nano mycustomscript.scr  and write your U-Boot commands: fatload mmc 2:1 0x80000000 gpio.bin cp.b 0x80000000 0x7e0000 0x10000 bootaux 0x7e0000   Now we can convert the text file to bootscript with mkimage. Syntax: mkimage -T script -n "Bootscript" -C none -d <input_file> <output_file> mkimage -T script -n "Bootscript" -C none -d mycustomscript.scr LCM4-bootscript   This will create a file called LCM4-bootscript (Or as your called it).   A way to load this bootscript file to U-Boot is using the UUU tool, in U-Boot set the device in fastboot with command: u-boot=> fastboot 0 Then in linux with the board connected through USB to PC run the command: sudo uuu -b fat_write LCM4-bootscript mmc 2:1 LCM4-bootscript   Now we have our bootscript in U-Boot in MMC 2:1.   Finally, we can run the bootscript in U-Boot: u-boot=> load mmc 2:1 ${loadaddr} LCM4-bootscript 158 bytes read in 2 ms (77.1 KiB/s) u-boot=> source ${loadaddr} ## Executing script at 40400000 6656 bytes read in 5 ms (1.3 MiB/s) ## No elf image at address 0x007e0000 ## Starting auxiliary core stack = 0x20020000, pc = 0x1FFE02CD...   And the Cortex M4 booted successfully:    I hope this can helps to you.   Best regards.   Salas.  
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GStreamer has a simple feature to enable tracing, allowing the developer to do basic debugging. These can be done in two ways: Adding the parameter --gst-debug=LIST to the pipeline (a pipeline is a executed gst-launch command) Prepending the environment variable GST_DEBUG=LIST' LIST is a a comma-separated argument, indicating the GStreamer elements to trace. For example, if one needs to trace the sink element      $ GST_DEBUG=*sink*:5 gst-launch playbin2 uri=file:///sample.avi or      $ gst-launch playbin2 uri=file:///sample.avi --gst-debug=*sink*:5 Both commands produces the same log. In case want to trace for than one element, so can simple add the <element>:5, for example      $ GST_DEBUG=mfw_v4lsink:5,vpudec:5 gst-launch playbin2 uri=file:///sample.avi The number 5 indicates the log category, where 5 is the highest (the most verbose log you can get) and 0 produces no output (5=LOG, 4=DEBUG, 3=INFO, 2=WARN, 1=ERROR). Log can be huge in each pipeline run. One way to filter it is using the grep command. Before grepping, one needs to redirect the standard error to the standard output (GStreamer log goes always to stderr), so      $ GST_DEBUG=mfw_v4lsink:5,vpudec:5 gst-launch playbin2 uri=file:///sample.avi 2>&1 | grep <filter string> In case the log needs to be shared, it is important to remove the 'color' of the log, again, one just needs to add the parameter --gst-debug-no-color or prepend the env variable GST_DEBUG_NO_COLOR=1 ----- More shell variables that GStreamer react, can be found here https://developer.gnome.org/gstreamer/0.10/gst-running.html
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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.
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Tested on Android 10 (android_Q10.0.0_1.0.0) After your the first BSP build the kernel sources are at: ${MY_ANDROID}/vendor/nxp-opensource/kernel_imx/ For the i.MX8M Mini, You can check the defconfig files being used on: ${MY_ANDROID}/device/fsl/imx8m/evk_8mm/UbootKernelBoardConfig.mk # imx8mm kernel defconfig TARGET_KERNEL_DEFCONFIG := android_defconfig TARGET_KERNEL_ADDITION_DEFCONF := android_addition_defconfig You could change one of them to add the desired configuration. - android_defconfig - is ${MY_ANDROID}/vendor/nxp-opensource/kernel_imx/arch/arm64/configs/android_defconfig - android_addition_defconfig - is on the same folder ${MY_ANDROID}/device/fsl/imx8m/evk_8mm/ "merge_config.sh" is called to generate the final defconfig file prior to building the kernel Check out: https://source.android.com/devices/architecture/kernel/config For example, I want to add DEVMEM support on my build: 1. Change the defconfig I add the line below to android_addition_defconfig CONFIG_DEVMEM=y (Or could have added it android_defconfig) 2. Build the kernel ./imx-make.sh kernel -c -j8 3. Verify your change After compiling, you can confirm your change by reading: ${MY_ANDROID}/out/target/product/evk_8mm/obj/KERNEL_OBJ/.config Then rebuild boot.img and reprogram the target.
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It is based on L3.0.35_GA4.1.0 BSP.   In default Linux BSP, there are 3 kinds of de-interlace mode, motion =0,1,2 mode, motion mode 0 and 1 will use three fields for de-interlace, and motion mode 2 wil use one field for de-interlace, so the whole fps is 30. In this mode, for motion mode 0 and 1, field 1,2,3 was used for first VDI output frame of display; and field 3,4,5 was used for second VDI output frame of display; field 5,6,7 was used for third VDI output frame of display. One field data (such as 2,4,6) was used only once, so there is data lost.   After applied these patches, the VDI de-interlace output will be 60fps: for motion mode 0 and 1, field 0,1,2 was used for first VDI output frame of display; and field 1,2,3 was used for second VDI output frame of display; field 2,3,4 was used for third VDI output frame of display. So all field data will be used twice, there is no video data lost, the VDI quality was improved.   Kernel patches: 0001-Add-MEM-to-VDI-to-MEM-support-for-IPU.patch 0002-Add-IPU-IC-memcpy-support.patch 0003-IPU-VDI-support-switch-odd-and-even-field-in-motion-.patch 0004-IPU-VDI-correct-vdi-top-field-setting.patch   mxc_v4l2_tvin_imx6_vdi_60fps.zip: this is the test application sample code.   Test commands, parameter "-vd" means double fps VDI: ./mxc_v4l2_tvin.out -ol 0 -ot 0 -ow 720 -oh 480 -m 0 -vd  
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Although you can develop your own driver to control GPIOs inside kernel space, there is a much simpler way for accessing GPIOs from user space. When timing requirements are not an issue, you are able to use GPIO-SYSFS. SYSFS is a virtual file system that exports some kernel internal framework functionalities to user space and GPIO is one of the frameworks that can have functionalities exported through SYSFS. The GPIO-SYSFS feature is available in all mainline kernels from 2.6.27 onwards. Configuring Kernel to export GPIO through SYSFS To enable GPIO in SYSFS, select the following kernel option: Device Drivers --->       --- GPIO Support             [*] /sys/class/gpio/... (sysfs interface) If you are using i.MX233 or i.MX28, after recompiling the kernel, do not forget to generate boot streams again, because this is not automatic even in ltib. Be sure that the pins you will try to use are really accessible as GPIO pins and were not requested by the kernel (gpio_request). If pin was gpio_request'ed, you will need to gpio_export the same pin inside the kernel in order to have it accessible through SYSFS. If pin is not set as GPIO by default, you will need to set IO MUX in the proper file inside <kernel>/arch/arm/mach-XXX. Accessing GPIO in user space After enabling GPIO-SYSFS feature, you can boot your device with the new kernel to make some tests. First you need to export the GPIO you want to test to the user space: echo XX > /sys/class/gpio/export XX shall be determined by the following algorithm: GPIOA_[B] is the GPIO you want to export, where "A" is the GPIO bank and "B" is the offset of the pin in the bank. if the first available GPIO bank is 0 // (iMX.28, for example)     XX = A*32 + B; else // first GPIO bank is 1     XX = (A-1)*32 + B; After exporting a GPIO pin, you shall be able to see the GPIO interface exported to: /sys/class/gpio/gpioXX Through this interface, you are now able to do things like: # Reading the pin value cat /sys/class/gpio/gpioXX/value # Changing pin direction echo in > /sys/class/gpio/gpioXX/direction echo out > /sys/class/gpio/gpioXX/direction # Toggling GPIO output level echo 0 > /sys/class/gpio/gpioXX/value echo 1 > /sys/class/gpio/gpioXX/value It is important to note that through the GPIO virtual filesystem it is only possible to deal with one GPIO pin at a time (per command).
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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. These are detailed programming aids for the registers associated with DRAM initialization (LPDDR3, DDR3, and LPDDR2). The last work sheet tab in the tool formats the register settings for use with the ARM DS5 debugger. It can also be used with the windows executable for the DDR Stress Test (note the removal of debugger specific commands in this tab). These programming aids were developed for internal NXP validation boards.   This tool serves as an aid to assist with programming the DDR interface of the MX7D and is based on the DDR initialization scripts developed for NXP boards and no guarantees are made by this tool.   The following are some general notes regarding this tool: The default configuration for the tool is to enable bank interleaving. Refer to the "How To Use" tab in the tool as a starting point to use this tool. The tool can be configured for one of the three memory types supported by the MX7D.  However, three separate programming aids are provided based on the DRAM type: LPDDR3, LPDDR2, and DDR3.  Therefore, you may use the tool pre-configured for your desired memory type as a starting point. The DRAM controller IP in MX7D is different from the MX6 series MMDC controller. Results from DRAM calibration may be updated for the following registers: DDR_PHY_OFFSET_WR_CON0 (0x30790030) and DDR_PHY_OFFSET_RD_CON0 (0x30790020).  Also, the MX7D memory map DRAM starting address is fixed at 0x80000000. Some of the CCM programming at the beginning of the DRAM initialization script (in the "DStream .ds file" tab) were automatically generated and in very few cases may involve writing to reserved bits, however, these writes to reserved bits are simply ignored. Note that in the "DStream .ds file" tab there are DS5 debugger specific commands that should be commented out or removed when using the DRAM initialization for non-debugger specific applications (like when porting to bootloaders). This tool may be updated on an as-needed basis for bug fixes or future improvements.  There is no schedule for aforementioned maintenance. For questions or additional assistance using this tool, please contact your local sales or FAE.
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The D-PHY PLL (in the red circle in the picture below) is the PLL that drives the MIPI Clock lane. It must be set in accordance with the video to be sent to the display.   Calculating the video bandwidth The video bandwidth is calculated with the following equation: Pixels per second = Horizontal res. x Vertical res. x Frame rate x Bits per pixel Taking as example the 1080p60 OLED display RM67191: Pixels per second = 1920 x 1080 x 60 x 24 Pixels per second = 2985984000 = 2,98Gpixels/sec Pixel clock calculation The Display pixel clock can be obtained on the display driver. In this example for RM67191, the pixel clock is 132Mpixel/sec, see file: panel-raydium-rm67191.c\panel\drm\gpu\drivers - linux-imx - i.MX Linux kernel  Line 530: .pixelclock = { 66000000, 132000000, 132000000 }, Or the number can be obtained with the following equation: pixel clock = (hactive + hfront_porch + hsync_len + hback_porch) x (vactive + vfront_porch + vsync_len + vback_porch) x frame rate pixel clock = (1080 + 20 + 2 +34) × (1920 + 10 + 2 + 4) x 60 pixel clock = 132000000 (rounded up) Bit clock calculation (clock lane) The mipi-dphy bit_clk is the output clock and is calculated on file sec-dsim.c (line 1283): sec-dsim.c\bridge\drm\gpu\drivers - linux-imx - i.MX Linux kernel  Bit clock can be calculated with the following equation: bit_clk = Pixel clock * Bits per pixel / Number of lanes In the case of 1980p60 (Raydium display), It is:   bit_clk = pixel clock * bits per pixel / number of lanes bit_clk = 132000000 * 24 / 4 bit_clk = 792000000 Other important timing parameters like 'p', 'm', 's' are obtained on the table in the following header file: sec_mipi_dphy_ln14lpp.h\imx\drm\gpu\drivers - linux-imx - i.MX Linux kernel 
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Debian is a free to use and redistribute Linux distribution that is widely used by the community for industrial and desktop applications.  This distribution started in 1993 as Debian Project with Ian Murdock inviting developers to contribute in one of the first Linux distributions.  Debian takes an important role in Linux world with a clear idea about be a full featured and free distribution with over than 59,000 packages provided as a free to use and distribute that supports a wide range of functionalities.  Currently, Debian 12 supports 9 architectures which makes it in a universal operating system that can be implemented in embedded systems, desktops or servers.  Finally, Debian has been an inspiration for well-known Linux distributions such as Kali and Ubuntu.  In this guide we will check the installation process of Debian 12 for NXP microprocessors i.MX family, specifically for i.MX8M Mini, i.MX8M Nano, i.MX8M Plus and i.MX93.  For this purpose, we divided the document in the following topics: Hardware Requirements Software Requirements Host Preparation SD Card Preparation Copying Bootloader  Copying Kernel and DTB files Debian Installation Configure Base System Boot your target References   Hardware Requirements Linux Host computer (Ubuntu 20.04 or later) USB Card reader or Micro SD to SD adapter SD Card Evaluation Kit Board for the i.MX8M Nano, i.MX8M Mini, i.MX8M Plus or i.MX93   Software Requirements Linux Ubuntu (20.04 and 24.04 tested) or Debian for host BSP version 6.1.55 for your specific target (Embedded Linux for i.MX Applications Processors | NXP Semiconductors)   Host Preparation For Debian installation we will require some specific packages for host.  You can download the packages using the following command: $ sudo apt install debian-archive-keyring debootstrap qemu-user-static We must validate the key to verify the archive using the command: $ sudo apt-key add /usr/share/keyrings/debian-archive-keyring.gpg If running an older release you need to get the unstable keyring package (because the version in your release is probably too old to have the current key) $ wget http://ftp.debian.org/debian/pool/main/d/debian-archive-keyring/debian-archive-keyring_2023.4_all.deb $ sudo dpkg -i debian-archive-keyring_2023.4_all.deb   SD Card Preparation The Linux kernel running on the Linux host assigns a device node to the SD/MMC card reader. The kernel might decide the device node name or udev rules might be used. In the following instructions, it is assumed that udev is not used. To identify the device node assigned to the SD/MMC card, carry out the following command: $ cat /proc/partitions   Partitioning the SD card On most Linux host operating systems, the SD card is mounted automatically upon insertion. Therefore, before running fdisk, make sure that the SD card is unmounted if it was previously mounted (through sudo umount /dev/sdx). Start by running fdisk with root permissions. Use the instructions above to determine the card ID. We are using sdx as an example. $ sudo fdisk /dev/sdx  Type the following parameters (each followed by <ENTER>): $fdisk: p # lists the current partitions $fdisk: d # to delete existing partitions. Repeat this until no unnecessary partitions $fdisk: n # create a new partition $fdisk: p # create a primary partition - use for both partitions $fdisk: 1 # the first partition $fdisk: 20480 # starting at offset sector $fdisk: 1024000 # ending position of the first partition to be used for the boot Images $fdisk: p # to check the partitions $fdisk: n # create a new partition $fdisk: p # create a primary partition $fdisk: 2 # the second partition $fdisk: 1228800 # starting at offset sector, which leaves enough space for the kernel, the bootloader and its configuration data $fdisk: <enter> # using the default value will create a partition that extends to the last sector of the media $fdisk: p # to check the partitions $fdisk: w # this writes the partition table to the media and fdisk exits   Copying Bootloader and Kernel In this section we will copy the bootloader and kernel image to SD card.  First, we can create a new directory to unzip the BSP downloaded from the NXP site.  $ mkdir debian-imx $ cd debian-imx $ unzip ~/Downloads/LF_v6.1.55-2.2.0_images_<board>.zip Where board is: IMX8MPEVK IMX8MNEVK IMX8MMEVK IMX93EVK Then, copy the U-Boot image. $ sudo dd if=<U-Boot_image> of=/dev/sdx bs=1k seek=<offset> conv=fsync Where offset is: 33 - for i.MX 8M Mini 32 - for i.MX 8M Nano, i.MX 8M Plus, and i.MX 9 The sectors of SD/eMMC before the “offset” KB are reserved. It may include the partition table.   Copying Kernel image and DTB files This section describes how to load the kernel image and DTB. The pre-built SD card image uses the VFAT partition for storing kernel image and DTB, which requires a VFAT partition that is mounted as a Linux drive, and the files are copied into it. This is the preferred method. Default: VFAT partition Format partition 1 on the card as VFAT with this command: $ sudo mkfs.vfat /dev/sdx1 Mount the formatted partition with this command: $ mkdir mountpoint $ sudo mount /dev/sdx1 mountpoint Copy the zImage and *.dtb files to the mountpoint by using cp. The device tree names should match $ sudo cp *.dtb mountpoint/ $sudo cp Image-<board_name>.bin mountpoint/Image Where board_name is: imx8mpevk imx8mnevk imx8mmevk imx93evk the one used by the variable specified by U-Boot. Unmount the partition with this command: $ sudo umount mountpoint   Debian Installation For Debian installation we will use the official tool debootstrap. This tool allows us to install Debian without a disk and run the system using qemu in a different architecture.  Before using debootstrap tool we need to format and mount the second partition of the SD card with the commands below: $ sudo mkfs.ext4 /dev/sdx2 $ sudo mount /dev/sdx2 mountpoint/ debootstrap can download the needed files directly from the archive when you run it. You can substitute any Debian archive mirror for http.us.debian.org/debian in the command below, preferably a mirror close to you network-wise. Mirrors are listed at http://www.debian.org/mirror/list $ sudo debootstrap --arch arm64 --foreign bookworm mountpoint/ http://ftp.debian.org/debian This step takes a while and depends on the resources of your host machine.   Configure Base System Now you’ve got a real Debian system, though rather lean, on disk. chroot into it: $ sudo cp /usr/bin/qemu-aarch64-static mountpoint/usr/bin $ sudo LANG=C.UTF-8 chroot mountpoint/ qemu-aarch64-static /bin/bash After chrooting you may need to set the terminal definition to be compatible with the Debian base system, for example: $ export TERM=xterm-color we need to finish the multi-stage boot strap $ /debootstrap/debootstrap --second-stage At this point /dev/ only contains very basic device files. For the next steps of the installation, additional device files may be needed. There are different ways to go about this and which method you should use depends on the host system you are using for the installation, whether you intend to use a modular kernel or not, and whether you want to use dynamic (e.g. using udev) or static device files for the new system. A few of the available options are: install the makedev package, and create a default set of static device files using (after chrooting) $ apt install makedev $ mount none /proc -t proc $ cd /dev $ MAKEDEV generic With these next steps we will be setting up the Debian system:   Setting fstab FSTAB is a configuration table designed to ease the burden of mounting and unmounting file systems to a machine. $ nano /etc/fstab # stock fstab - you probably want to override this with a machine specific one /dev/root / auto defaults 1 1 proc /proc proc defaults 0 0 devpts /dev/pts devpts mode=0620,ptmxmode=0666,gid=5 0 0 tmpfs /run tmpfs mode=0755,nodev,nosuid,strictatime 0 0 tmpfs /var/volatile tmpfs defaults 0 0 # uncomment this if your device has a SD/MMC/Transflash slot #/dev/mmcblk0p1 /media/card auto defaults,sync,noauto 0 0   Setting Timezone The following command allows you to choose your timezone. $ dpkg-reconfigure tzdata   Configure apt Debootstrap will have created a very basic /etc/apt/sources.list that will allow installing additional packages. However, you may want to add some additional sources, for example for source packages and security updates: $ nano /etc/apt/sources.list deb http://deb.debian.org/debian bookworm main non-free-firmware deb-src http://deb.debian.org/debian bookworm main non-free-firmware deb http://deb.debian.org/debian-security/ bookworm-security main non-free-firmware deb-src http://deb.debian.org/debian-security/ bookworm-security main non-free-firmware deb http://deb.debian.org/debian bookworm-updates main non-free-firmware deb-src http://deb.debian.org/debian bookworm-updates main non-free-firmware Make sure to run the apt update after you have made changes to the sources list   Configure locales and keyboard To configure your locale settings to use a language other than English, install the locales support package and configure it. Currently, the use of UTF-8 locales is recommended. $ apt install locales $ dpkg-reconfigure locales To configure your keyboard (if needed): $ apt install console-setup $ dpkg-reconfigure keyboard-configuration Note that the keyboard cannot be set while in the chroot, but will be configured for the next reboot   Adding Users $ apt install sudo $ adduser imx $ usermod -aG sudo imx $ nano /etc/sudoers imx ALL=(ALL:ALL) ALL   Tasksel Installation As mentioned earlier, the installed system will be very basic. If you would like to make the system a bit more mature, there is an easy method to install all packages with “standard” priority: $ tasksel install standard $ apt clean $ exit $ sudo umount mountpoint/ $sync   Boot your target Now, you can boot your target from your SD Card. (Review your specific target documentation)   Configure Networking (after booting target) Based on Debian official documentation for new systems the common names for network interfaces such as eth0 or wlan0 are not used. Therefore, we will need to list the interfaces using: $ ls /sys/class/net To have ethernet connection we will need to create a file in the path etc/network/. $ sudo nano etc/network/interfaces Type the following commands on the file: auto lo iface lo inet loopback auto end0 iface end0 inet dhcp   Install Neofetch (Optional) $ apt install neofetch   Outputs  Debian 12 running on i.MX8MP Debian 12 running on i.MX93   References Chapter 1. Definitions and overview. (2021, January). Retrieved May 30, 2024, from https://www.debian.org/doc/manuals/debian-faq/basic-defs.en.html Debian GNU/Linux Installation Guide. (2024). https://www.debian.org/releases/stable/i386/install.en.pdf Arm64Port. (n.d.). https://wiki.debian.org/Arm64Port i.MX Linux User's Guide (nxp.com)
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All, This document will help you to understand the " YOCTO PROJECT COMMUNITY LAYERS" and the "YOCTO PROJECT FREESCALE OFFICIAL RELEASE" differences and where the layer content is coming from.   Best Regards, Luis
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What is a device tree? The device tree is a data structure that is passed to the Linux kernel to describe the physical devices in a system. Before device trees came into use, the bootloader (for example, U-Boot) had to tell the kernel what machine type it was booting. Moreover, it had to pass other information such as memory size and location, kernel command line, etc. Sometimes, the device tree is confused with the Linux Kernel configuration, but the device tree specifies what devices are available and how they are accessed, not whether the hardware is used. The device tree is a structure composed of nodes and properties: Nodes: The node name is a label used to identify the node. Properties: A node may contain multiple properties arranged with a name and a value. Phandle: Property in one node that contains a pointer to another node. Aliases: The aliases node is an index of other nodes. A device tree is defined in a human-readable device tree syntax text file such as .dts or .dtsi. The machine has one or several .dts files that correspond to different hardware configurations. With these .dts files we can compile them into a device tree binary (.dtb) blobs that can either be attached to the kernel binary (for legacy compatibility) or, as is more commonly done, passed to the kernel by a bootloader like U-Boot. What is Devshell? The Devshell is a terminal shell that runs in the same context as the BitBake task engine. It is possible to run Devshell directly or it may spawn automatically. The advantage of this tool is that is automatically included when you configure and build a platform project so, you can start using it by installing the packages and following the setup of i.MX Yocto Project User's Guide on section 3 “Host Setup”. Steps: Now, let’s see how to compile your device tree files of i.MX devices using Devshell. On host machine. Modify or make your device tree on the next path: - 64 bits. ~/imx-yocto-bsp/<build directory>/tmp/work-shared/<machine>/kernel-source/arch/arm64/boot/dts/freescale - 32 bits. ~/imx-yocto-bsp/<build directory>/tmp/work-shared/<machine>/kernel-source/arch/arm/boot/dts To compile, it is needed to prepare the environment as is mentioned on i.MX Yocto Project User's Guide on section 5.1 “Build Configurations”. $ cd ~/imx-yocto-bsp $ DISTRO=fsl-imx-xwayland MACHINE=<machine> source imx-setup-release.sh -b <build directory> $ bitbake -c devshell virtual/kernel (it will open a new window) On Devshell window. $ make dtbs (after finished, close the Devshell window) On host machine. $ bitbake -c compile -f virtual/kernel $ bitbake -c deploy -f virtual/kernel This process will compile all the device tree files linked to the machine declared on setup environment and your device tree files will be deployed on the next path: ~/imx-yocto-bsp/<build directory>/tmp/deploy/images/<machine> I hope this article will be helpful. Best regards. Jorge.
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In this article, some experiments are done to verify the capability of i.MX6DQ on video playback under different VPU clocks. 1. Preparation Board: i.MX6DQ SD Bitstream: 1080p sunflower with 40Mbps, it is considered as the toughest H264 clip. The original clip is copied 20 times to generate a new raw video (repeat 20 times of sun-flower clip) and then encapsulate into a mp4 container. This is to remove and minimize the influence of startup workload of gstreamer compared to vpu unit test. Kernels: Generate different kernel with different VPU clock setting: 270MHz, 298MHz, 329MHz, 352MHz, 382MHz. test setting: 1080p content decoding and display with 1080p device. (no resize) 2. Test command for VPU unit test and Gstreamer The tiled format video playback is faster than NV12 format, so in below experiment, we choose tiled format during video playback. Unit test command: (we set the frame rate -a 70, higher than 1080p 60fps HDMI refresh rate)     /unit_tests/mxc_vpu_test.out -D "-i /media/65a78bbd-1608-4d49-bca8-4e009cafac5e/sunflower_2B_2ref_WP_40Mbps.264 -f 2 -y 1 -a 70" Gstreamer command: (free run to get the highest playback speed)     gst-launch filesrc location=/media/65a78bbd-1608-4d49-bca8-4e009cafac5e/sunflower_2B_2ref_WP_40Mbps.mp4 typefind=true ! aiurdemux ! vpudec framedrop=false ! queue max-size-buffers=3 ! mfw_v4lsink sync=false 3. Video playback framerate measurement During test, we enter command "echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor" to make sure the CPU always work at highest frequency, so that it can respond to any interrupt quickly. For each testing point with different VPU clock, we do 5 rounds of tests. The max and min values are removed, and the remaining 3 data are averaged to get the final playback framerate. #1 #2 #3 #4 #5 Min Max Avg Dec Playback Dec Playback Dec Playback Dec Playback Dec Playback Playback Playback Playback 270M unit test 57.8 57.3 57.81 57.04 57.78 57.3 57.87 56.15 57.91 55.4 55.4 57.3 56.83 GST 53.76 54.163 54.136 54.273 53.659 53.659 54.273 54.01967 298M unit test 60.97 58.37 60.98 58.55 60.97 57.8 60.94 58.07 60.98 58.65 57.8 58.65 58.33 GST 56.755 49.144 53.271 56.159 56.665 49.144 56.755 55.365 329M unit test 63.8 59.52 63.92 52.63 63.8 58.1 63.82 58.26 63.78 59.34 52.63 59.52 58.56667 GST 57.815 55.857 56.862 58.637 56.703 55.857 58.637 57.12667 352M unit test 65.79 59.63 65.78 59.68 65.78 59.65 66.16 49.21 65.93 57.67 49.21 59.68 58.98333 GST 58.668 59.103 56.419 58.08 58.312 56.419 59.103 58.35333 382M unit test 64.34 56.58 67.8 58.73 67.75 59.68 67.81 59.36 67.77 59.76 56.58 59.76 59.25667 GST 59.753 58.893 58.972 58.273 59.238 58.273 59.753 59.03433 Note: Dec column means the vpu decoding fps, while Playback column means overall playback fps. Some explanation: Why does the Gstreamer performance data still improve while unit test is more flat? On Gstreamer, there is a vpu wrapper which is used to make the vpu api more intuitive to be called. So at first, the overall GST playback performance is constrained by vpu (vpu dec 57.8 fps). And finally, as vpu decoding performance goes to higher than 60fps when vpu clock increases, the constraint becomes the display refresh rate 60fps. The video display overhead of Gstreamer is only about 1 fps, similar to unit test. Based on the test result, we can see that for 352MHz, the overall 1080p video playback on 1080p display can reach ~60fps. Or if time sharing by two pipelines with two displays, we can do 2 x 1080p @ 30fps video playback. However, this experiment is valid for 1080p video playback on 1080p display. If for interlaced clip and display with size not same as 1080p, the overall playback performance is limited by some postprocessing like de-interlacing and resize.
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Inside IPU there are two block where color space conversion can be made: IC (Image Converter) and DP (Display processor). On Linux, the CSC parameters are located at IPU (IC and DP) drivers, linux/drivers/mxc/ipu3 folder. All negative coefficients are represented using two's complement. Linux Image Converter driver: The parameters are set on function _init_csc: http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/mxc/ipu3/ipu_ic.c?h=imx_3.14.28_1.0.0_ga static void _init_csc(struct ipu_soc *ipu, uint8_t ic_task, ipu_color_space_t in_format, ipu_color_space_t out_format, int csc_index) { /* * Y = 0.257 * R + 0.504 * G + 0.098 * B + 16; * U = -0.148 * R - 0.291 * G + 0.439 * B + 128; * V = 0.439 * R - 0.368 * G - 0.071 * B + 128; */ static const uint32_t rgb2ycbcr_coeff[4][3] = { {0x0042, 0x0081, 0x0019}, {0x01DA, 0x01B6, 0x0070}, {0x0070, 0x01A2, 0x01EE}, {0x0040, 0x0200, 0x0200}, /* A0, A1, A2 */ }; /* transparent RGB->RGB matrix for combining */ static const uint32_t rgb2rgb_coeff[4][3] = { {0x0080, 0x0000, 0x0000}, {0x0000, 0x0080, 0x0000}, {0x0000, 0x0000, 0x0080}, {0x0000, 0x0000, 0x0000}, /* A0, A1, A2 */ }; /* R = (1.164 * (Y - 16)) + (1.596 * (Cr - 128));   G = (1.164 * (Y - 16)) - (0.392 * (Cb - 128)) - (0.813 * (Cr - 128));   B = (1.164 * (Y - 16)) + (2.017 * (Cb - 128); */ static const uint32_t ycbcr2rgb_coeff[4][3] = { {149, 0, 204}, {149, 462, 408}, {149, 255, 0}, {8192 - 446, 266, 8192 - 554}, /* A0, A1, A2 */ }; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ Linux Display Processor driver: The parameters are set on constants (rgb2ycbcr_coeff and ycbcr2rgb_coeff): http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/mxc/ipu3/ipu_disp.c?h=imx_3.14.28_1.0.0_ga /* Y = R * 1.200 + G * 2.343 + B * .453 + 0.250;   U = R * -.672 + G * -1.328 + B * 2.000 + 512.250.;   V = R * 2.000 + G * -1.672 + B * -.328 + 512.250.;*/ static const int rgb2ycbcr_coeff[5][3] = { {0x4D, 0x96, 0x1D}, {-0x2B, -0x55, 0x80}, {0x80, -0x6B, -0x15}, {0x0000, 0x0200, 0x0200}, /* B0, B1, B2 */ {0x2, 0x2, 0x2}, /* S0, S1, S2 */ }; /* R = (1.164 * (Y - 16)) + (1.596 * (Cr - 128));   G = (1.164 * (Y - 16)) - (0.392 * (Cb - 128)) - (0.813 * (Cr - 128));   B = (1.164 * (Y - 16)) + (2.017 * (Cb - 128); */ static const int ycbcr2rgb_coeff[5][3] = { {0x095, 0x000, 0x0CC}, {0x095, 0x3CE, 0x398}, {0x095, 0x0FF, 0x000}, {0x3E42, 0x010A, 0x3DD6}, /*B0,B1,B2 */ {0x1, 0x1, 0x1}, /*S0,S1,S2 */ };‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍
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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
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This document explains how to bring-up u-boot & Linux via JTAG This procedure has been tested on: i.MX6 Solo X Sabre SD i.MX6UL EVK Prerequistes: Get the latest BSP for your board. This procedure was tested with L4.1.15. Build the 'core-image-minimal' image to bring-up your board (Detailed steps here) Optional- Build a meta-toolchain for your device 1.- Set board to boot from Serial dowloader mode or set it to boot from the SD card and remove the sd card We basically want the board to stall in boot ROM to attach to the target. 2.- Connect JTAG probe and turn on the board The device should stall trying to establish a connection to download an image, this will allow us to attach to the target. 3.- Load Device Configuration Data In 'normal' boot sequence the boot ROM takes care of reading the DCD and configuring the device accordingly, but in this case we are skipping this sequence and we need to configure the device manually. The script used by Lauterbach to parse and configure the device is called dcd_interpreter.cmm and can be found here. Search for the package for your specific device. The DCD configuration for your board should be on your u-boot directory: yocto_build_dir/tmp/work/<your board>imx6ulevk/u-boot-imx/<u-boot_version>2016.03-r0/git under board/freescale/<name of your board>mx6ul_14x14_evk/imximage.cfg This file (imximage.cfg) contains all the data to bring up DRAM among other early configuration options. 4.- Load U-boot If an SREC file of U-boot is not present build it (meta-toolchain installed required) the SREC file contains all the information required by the probe to load it and makes this process easier. To build the SREC simply type: make <your board defconfig>mx6ul_14x14_evk_defconfig  (all supported boards are found under u-boot_dir/configs) make If you cannot build an SREC or do not want to, you can use the u-boot.imx (located under yocto_build_dir/tmp/deploy/images/<your board name>/) or u-boot.bin files but you will need to figure out the start address and load address for these files, this can be done by examining the IVT on u-boot.imx (here is a useful document explaining the structure of the IVT). Let U-boot run and you should see its output on the console I will try to boot from several sources but it will fail and show you the prompt. 5.- Create RAMDisk After building the core-image-minimal you will have all the required files under yocto_build_dir/tmp/deploy/images/<your board name>/ You will need: zImage.bin - zImage--<Linux Version>--<your board>.bin Device tree blob - zImage--<Linux Version>--<your board>.dtb Root file system - core-image-minimal-<your board>.rootfs.ext4 We need to create a RAMDisk out of the root file system we now have, these are the steps to do so: Compress current Root file system using gzip: gzip core-image-minimal-<your board>.rootfs.ext4 If you want to keep the original file use: gzip -c core-image-minimal-<your board>.rootfs.ext4 > core-image-minimal-<your board>.rootfs.ext4.gz Create RAMDisk using mkimage: mkimage -A arm -O linux -T ramdisk -C gzip -n core-image-minimal -d core-image-minimal-<your board>.rootfs.ext4.gz core-image-minimal-RAMDISK.rootfs.ext4.gz.u-boot Output: Image Name: core-image-minimal Created: Tue May 23 11:28:55 2017 Image Type: ARM Linux RAMDisk Image (gzip compressed) Data Size: 3017939 Bytes = 2947.21 kB = 2.88 MB Load Address: 00000000 Entry Point: 00000000 Here are some details on mkimage usage Usage: mkimage -l image -l ==> list image header information mkimage [-x] -A arch -O os -T type -C comp -a addr -e ep -n name -d data_file[:data_file...] image -A ==> set architecture to 'arch' -O ==> set operating system to 'os' -T ==> set image type to 'type' -C ==> set compression type 'comp' -a ==> set load address to 'addr' (hex) -e ==> set entry point to 'ep' (hex) -n ==> set image name to 'name' -d ==> use image data from 'datafile' -x ==> set XIP (execute in place) mkimage [-D dtc_options] [-f fit-image.its|-F] fit-image -D => set options for device tree compiler -f => input filename for FIT source Signing / verified boot not supported (CONFIG_FIT_SIGNATURE undefined) mkimage -V ==> print version information and exit 6.- Modify U-boot's environment variables Now we need to modify U-boot's bootargs as follows: setenv bootargs console=${console},${baudrate} root=/dev/ram rw We need to find out the addresses where u-boot will expect the zImage, the device tree and the initial RAMDisk, we can do it as follows: => printenv fdt_addr fdt_addr=0x83000000 => printenv initrd_addr initrd_addr=0x83800000 => printenv loadaddr loadaddr=0x80800000 Where: fdt_addr -> Device tree blob load address initrd_addr -> RAMDisk load address loadaddr -> zImage load address 7.- Load zImage, DTB and RAMDisk Now we know where to load our zImage, device tree blob and RAMDisk, on Lauterbach this can be achieved by running the following commands: Stop the target and execute: data.load.binary zImage.bin 0x80800000 data.load.binary Your_device.dtb 0x83000000 data.load.binary core-image-minimal-RAMDISK.rootfs.ext4.gz.u-boot 0x83800000 Let the device run again and deattach from the device in lauterbach this is achieved by: go SYStem.mode.NoDebug start the boot process on u-boot as follows: bootz ${loadaddr} ${initrd_addr} ${fdt_addr} You should now see the Linux kernel boot process on your terminal: After the kernel boots you should see its prompt on your terminal: Since we are running out of RAM there is no way for us to save u-boot's environment variables, but you can modify the source and compile u-boot with the new bootargs, by doing so you can create a Load script that loads all the binaries hits go and the boot process will continue automatically. One way to achieve this is to modify the configuration file under U-boot_dir/include/configs/<your board>.h find the mfgtool_args and modify accordingly. The images attached to this thread have been modified as mentioned.
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The purpose of this document is to provide extended guidance for the selection of compatible LPDDR4/4X memory devices that are supported by the i.MX 93 series of processors. In all cases, it is strongly recommended to follow the DRAM layout guidelines outlined in the NXP Hardware Developer's Guides for the specific SoCs. The i.MX 93 series of processors supports different packages, and each have their own maximum supported LPDDR4/4x data rates. Please refer to the respective datasheets. Memory devices with binary densities (e.g., 1 GB, 2 GB, 4 GB) are preferred because they simplify memory management by aligning with system addressing schemes and reducing software complexity. NOTE: Some of the LPDDR4/4X devices may not support operation at low speeds and in addition, DQ ODT may not be active, which can impact signal integrity at these speeds. If low-speed operation is planned in the use case, please consult with the memory vendor about the configuration aspects and possible customization of the memory device so correct functionality is ensured. LPDDR4/4X - Maximum Supported Densities SoC Max Data bus width Maximum density Assumed memory organization Notes i.MX 93 (i.MX 93xx) 16-bit 16 Gb / (2 GB) single rank, single channel device with 17-row addresses (R0 - R16) 1, 2, 3   LPDDR4/4X - List of Validated Memories The validation process is an ongoing effort - regular updates of the table are expected. SoC Density Memory Vendor Validated Memory Part# Notes i.MX 93 16 Gb/ (2 GB) Micron LPDDR4/4x: MT53E1G16D1FW-046 AAT:A  (Z32N) MT53E1G16D1ZW-046 AAT:C (Z42N) 7   4, 8 8 Gb/ (1 GB) Micron LPDDR4/4x: MT53D512M16D1DS-046 AAT (Z11M) 4, 10 16 Gb/ (2 GB) Micron LPDDR4/4x: MT53E1G32D2FW-046 AUT:B (Z42M) 4, 5, 10 8 Gb/ (1 GB) Nanya LPDDR4: NT6AN512M16AV-J1I LPDDR4x: NT6AP512M16BV-J1I 4, 8 4 Gb/ (512 MB) Nanya LPDDR4x: NT6AP256M16AV  4, 8 16 Gb/ (2 GB) Kingston LPDDR4: D1611PM3BDGUI-U 4, 8 16 Gb/ (2 GB) Kingston LPDDR4: C1612PC2WDGTKR-U  7, 9 4 Gb/ (512 MB) ISSI LPDDR4: IS43LQ16256B-062BLI 4, 8 2Gb / (256 MB) ISSI LPDDR4: IS43LQ16128A-062BSLI 4, 6, 8   8 Gb/ (1 GB) CXMT LPDDR4/4x: CXDB4CBAM-EA-M 4, 9 16 Gb/ (2 GB) JSC LPDDR4x: JSL4BAG167ZAMF  4, 8 8 Gb/ (1 GB) JSC LPDDR4x: JSL4B8G168ZAMF-05x  4, 8 4 Gb/ (512 MB) JSC LPDDR4x: JSL4A4G168ZAMF-05 4, 8 2Gb / (256 MB) Winbond  LPDDR4x: W66BQ6NBHAGJ 4, 6, 8 8Gb / (1 GB) IM (Intelligent Memory) LPDDR4x: IM8G16L4JCB-046I 4, 11 16Gb / (2 GB) IM (Intelligent Memory) LPDDR4/4x: IMAG16L4KBBG 4, 8 4Gb / (512 MB) Samsung LPDDR4: K4F4E164HD-THCL 4, 8 8 Gb / (1 GB) AM (Alliance Memory) LPDDR4X: AS4C512M16MD4V-053BIN 4, 8 4 Gb / (512 MB) ISSI LPDDR4/4X: IS43LQ16256B-053BLI 4, 8 8 Gb / (1 GB) ISSI LPDDR4/4X: IS46LQ16512B-046BLA2 4, 8 32 Gb / (4GB) 16 Gb / (2Gb) usable by i.MX93 ISSI LPDDR4/4X: IS46LQ32K01B-046BLI 4, 8   Note 1: The numbers are based purely on the IP documentation for the DDR Controller and the DDR PHY, on the settings of the implementation parameters chosen for their integration into the SoC, SoC reference manual and on the JEDEC standards JESD209-4B/JESD209-4-1 (LPDDR4/4X). Therefore, they are not backed by validation, unless said otherwise and there is no guarantee that an SoC with the specific density and/or desired internal organization is offered by the memory vendors. Should the customers choose to use the maximum density and assume it in the intended use case, they do it at their own risk. Note 2: Byte-mode LPDDR4/4X devices (x16 channel internally split between two dies, x8 each) of any density are not supported therefore, the numbers are applicable only to devices with x16 internal organization (referred to as "standard" in the JEDEC specification). Note 3: The SoC also supports dual rank single channel devices therefore, 16Gb/2GB density can be also achieved by using a dual rank single channel device with 16-row addresses (R0 - R15). Note 4: The memory part number did not undergo full JEDEC verification however, it passed all functional testing items. Note 5: This is a dual channel x32 device. Since i.MX93 only supports 16-bit LPDDR4/X data bus, it can only interface with one of the channels and therefore, utilize only half of the device's density. As indicated in the table - the device has 32Gb/4GB density however, only 16Gb/2GB can be used. There is no functional problem with using only one channel of a dual channel device as the channels are independent in LPDDR4/4X.  Note 6: This is a new JEDEC 100 ball package, half the size of the standard 200 ball package. This 100 ball package has the same performance and functionality as the 200 ball package, and has the added advantage of being smaller and cheaper than the standard package. Note 7: This device has been EoLed by the manufacturer and has been updated by a new memory part number  Note 8: Part is active. Reviewed Nov 2025 Note 9: Part is obsolete. Note 10: This device will be EoLed in Q2 24 by the manufacturer and will not be updated by a new memory part number Note 11: DQ eye marginalities were identified during TSA analysis. vTSA and stability testing did not identify any issues.
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Hello i.MX Community. Attached there is a guide on how to install Ubuntu trusty on i.MX7D-SD board Basically it explains all steps to install and to have running ubuntu core 14.04 on the Freescale i.Mx7D-SDB: I hope you find the document and projects useful! Regards!
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