For some applications, we need to reduce the CPU Frequency, but if you are not familiar with our BSP or our devices probably you need some help to do some configurations.   In this post, I will share the configuration to set up lower frequencies (100MHz, 200MHz, 400Mhz, 600MHz, 800MHz, and 1000MHz) on iMX8MP, iMX8MN, and iMX8MM.   Note: Works on Kernel 6.1.xx (not tested on oldest BSP)   1- We have to modify the PLL driver to set the proper parameters to lower frequencies. The file to modify is "clk-pll14xx.c" adding the following lines:   https://github.com/nxp-imx/linux-imx/blob/770c5fe2c1d1529fae21b7043911cd50c6cf087e/drivers/clk/imx/clk-pll14xx.c#L57   static const struct imx_pll14xx_rate_table imx_pll1416x_tbl[] = { PLL_1416X_RATE(1800000000U, 225, 3, 0), PLL_1416X_RATE(1600000000U, 200, 3, 0), PLL_1416X_RATE(1500000000U, 375, 3, 1), PLL_1416X_RATE(1400000000U, 350, 3, 1), PLL_1416X_RATE(1200000000U, 300, 3, 1), PLL_1416X_RATE(1000000000U, 250, 3, 1), PLL_1416X_RATE(800000000U, 200, 3, 1), PLL_1416X_RATE(750000000U, 250, 2, 2), PLL_1416X_RATE(700000000U, 350, 3, 2), PLL_1416X_RATE(600000000U, 300, 3, 2), + PLL_1416X_RATE(400000000U, 200, 3, 2), + PLL_1416X_RATE(200000000U, 200, 3, 3), + PLL_1416X_RATE(100000000U, 200, 3, 4), };   2- Once the pll driver has been modified, only we have to add the values on the opp-table according to the device that you will use.   2.1- For iMX 8MP:   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mp.dtsi         a53_opp_table: opp-table { compatible = "operating-points-v2"; opp-shared; + opp-100000000 { + opp-hz = /bits/ 64 <100000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-200000000 { + opp-hz = /bits/ 64 <200000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-400000000 { + opp-hz = /bits/ 64 <400000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-600000000 { + opp-hz = /bits/ 64 <600000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-800000000 { + opp-hz = /bits/ 64 <800000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-1000000000 { + opp-hz = /bits/ 64 <1000000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0x8a0>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; opp-1200000000 { opp-hz = /bits/ 64 <1200000000>;   2.2 For iMX8MM:   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mm.dtsi     a53_opp_table: opp-table { compatible = "operating-points-v2"; opp-shared; + opp-100000000 { + opp-hz = /bits/ 64 <100000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-200000000 { + opp-hz = /bits/ 64 <200000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-400000000 { + opp-hz = /bits/ 64 <400000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-600000000 { + opp-hz = /bits/ 64 <600000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-800000000 { + opp-hz = /bits/ 64 <800000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-1000000000 { + opp-hz = /bits/ 64 <1000000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xe>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; opp-1200000000 { opp-hz = /bits/ 64 <1200000000>;   2.3- For iMX8MN:   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mn.dtsi   compatible = "operating-points-v2"; opp-shared; + opp-100000000 { + opp-hz = /bits/ 64 <100000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + + opp-200000000 { + opp-hz = /bits/ 64 <200000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + + opp-400000000 { + opp-hz = /bits/ 64 <400000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + + opp-600000000 { + opp-hz = /bits/ 64 <600000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + + opp-800000000 { + opp-hz = /bits/ 64 <800000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + + opp-1000000000 { + opp-hz = /bits/ 64 <1000000000>; + opp-microvolt = <850000>; + opp-supported-hw = <0xb00>, <0x7>; + clock-latency-ns = <150000>; + opp-suspend; + }; + opp-1200000000 { opp-hz = /bits/ 64 <1200000000>; opp-microvolt = <850000>;   After that, you should note the changes under Linux.   These commands return information about the system and the current settings.   • The kernel is pre-configured to support only certain frequencies. The list of frequencies currently supported can be obtained from: cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies   • To get the available scaling governors: cat /sys/devices/system/cpu/*/cpufreq/scaling_available_governors   • To check the current CPU frequency: cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_cur_freq   The frequency is displayed depending on the governor set.   • To check the maximum frequency: cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_max_freq   • To check the minimum frequency: cat /sys/devices/system/cpu/*/cpufreq/cpuinfo_min_freq   These commands set a constant CPU frequency:   • Use the maximum frequency: echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor   • Use the current frequency to be the constant frequency: echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor   • The following two commands set the scaling governor to a specified frequency, if that frequency is supported.   If the frequency is not supported, the closest supported frequency is used:   echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor echo <frequency> > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed    

Platform: Demo images, i.MX8MPlus EVK   Some customer need test ffs gadget function on i.MX8MPlus EVK. Here is demo for ffs test, please connect EVK and Ubuntu PC before test.   Test script: #!/bin/sh # Setup the device (configfs) modprobe libcomposite mkdir -p config mount none config -t configfs cd config/usb_gadget/ mkdir g1 cd g1 echo 0x1fc9 >idVendor echo 0x0146 >idProduct mkdir strings/0x409 echo 12345 >strings/0x409/serialnumber echo "Signal 11" >strings/0x409/manufacturer echo "Test" >strings/0x409/product mkdir configs/c.1 mkdir configs/c.1/strings/0x409 echo "Config1" >configs/c.1/strings/0x409/configuration # Setup functionfs mkdir functions/ffs.usb0 ln -s functions/ffs.usb0 configs/c.1 cd ../../../ mkdir -p ffs mount usb0 ffs -t functionfs cd ffs ffs-test 64 & # from the Linux kernel, with mods! sleep 3 cd .. # Enable the USB device echo 38100000.usb > config/usb_gadget/g1/UDC   EVK log root@imx8mpevk:~# ./test2.sh [ 17.859597] file system registered ffs-test: dbg: ep0: writing descriptors (in v2 format) ffs-test: dbg: ep0: writing strings ffs-test: dbg: ep1: starting ffs-test: dbg: ep2: starting ffs-test: dbg: ep1: starts ffs-test: dbg: ep0: starts ffs-test: dbg: ep2: starts Event BIND Event ENABLE Ubuntu PC log: lzm@lzm-GL552VW:~$ lsusb -D /dev/bus/usb/001/008 Device: ID 1fc9:0146 NXP Semiconductors Test Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.10 bDeviceClass 0 bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x1fc9 NXP Semiconductors idProduct 0x0146 bcdDevice 6.01 iManufacturer 1 Signal 11 iProduct 2 Test iSerial 3 12345 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 0x0020 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 4 Config1 bmAttributes 0x80 (Bus Powered) MaxPower 2mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 2 bInterfaceClass 255 Vendor Specific Class bInterfaceSubClass 0 bInterfaceProtocol 0 iInterface 5 Source/Sink Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x01 EP 1 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 1 Binary Object Store Descriptor: bLength 5 bDescriptorType 15 wTotalLength 0x0016 bNumDeviceCaps 2 USB 2.0 Extension Device Capability: bLength 7 bDescriptorType 16 bDevCapabilityType 2 bmAttributes 0x0000010e BESL Link Power Management (LPM) Supported BESL value 256 us SuperSpeed USB Device Capability: bLength 10 bDescriptorType 16 bDevCapabilityType 3 bmAttributes 0x00 wSpeedsSupported 0x000f Device can operate at Low Speed (1Mbps) Device can operate at Full Speed (12Mbps) Device can operate at High Speed (480Mbps) Device can operate at SuperSpeed (5Gbps) bFunctionalitySupport 1 Lowest fully-functional device speed is Full Speed (12Mbps) bU1DevExitLat 0 micro seconds bU2DevExitLat 0 micro seconds Device Status: 0x0001 Self Powered  

How to use UART4 on iMX8M from Linux User Space   The UART4 on iMX8MM-EVK and iMX8MN-EVK are thinking of debugging the M core which is not usable on Linux user space by default on pre-compiled images.   To use the UART4 on Linux user space you have to do the next modifications on the device tree and atf to assign that peripheral to Linux User Space     https://github.com/nxp-imx/imx-atf/blob/lf_v2.6/plat/imx/imx8m/imx8mm/imx8mm_bl31_setup.c     iMX8MN-EVK   imx8mn_bl31_setup.c   https://github.com/nxp-imx/imx-atf/blob/lf_v2.6/plat/imx/imx8m/imx8mn/imx8mn_bl31_setup.c   /* Master domain assignment */ RDC_MDAn(RDC_MDA_M7, DID1), /* peripherals domain permission */ - RDC_PDAPn(RDC_PDAP_UART4, D1R | D1W), + RDC_PDAPn(RDC_PDAP_UART4, D0R | D0W), RDC_PDAPn(RDC_PDAP_UART2, D0R | D0W), RDC_PDAPn(RDC_PDAP_RDC, D0R | D0W | D1R),       Device tree configurations for iMX8MN-EVK   iMX8MN-EVK.dtsi   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi   &uart3 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart3>; assigned-clocks = <&clk IMX8MN_CLK_UART3>; assigned-clock-parents = <&clk IMX8MN_SYS_PLL1_80M>; uart-has-rtscts; status = "okay"; }; + &uart4 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_uart4>; + assigned-clocks = <&clk IMX8MN_CLK_UART4>; + assigned-clock-parents = <&clk IMX8MN_SYS_PLL1_80M>; + status = "okay"; + }; ********************** pinctrl_uart3: uart3grp { fsl,pins = < MX8MN_IOMUXC_ECSPI1_SCLK_UART3_DCE_RX 0x140 MX8MN_IOMUXC_ECSPI1_MOSI_UART3_DCE_TX 0x140 MX8MN_IOMUXC_ECSPI1_SS0_UART3_DCE_RTS_B 0x140 MX8MN_IOMUXC_ECSPI1_MISO_UART3_DCE_CTS_B 0x140 >; }; + pinctrl_uart4: uart4grp { + fsl,pins = < + MX8MN_IOMUXC_UART4_RXD_UART4_DCE_RX 0x140 + MX8MN_IOMUXC_UART4_TXD_UART4_DCE_TX 0x140 + >; + };   iMX8MM-EVK   https://github.com/nxp-imx/imx-atf/blob/lf_v2.6/plat/imx/imx8m/imx8mm/imx8mm_bl31_setup.c   imx8mm_bl31_setup.c   /* Master domain assignment */ RDC_MDAn(RDC_MDA_M7, DID1), /* peripherals domain permission */ - RDC_PDAPn(RDC_PDAP_UART4, D1R | D1W), + RDC_PDAPn(RDC_PDAP_UART4, D0R | D0W), RDC_PDAPn(RDC_PDAP_UART2, D0R | D0W), RDC_PDAPn(RDC_PDAP_RDC, D0R | D0W | D1R),   Device tree configurations for iMX8MM-EVK   iMX8MM-EVK.dtsi   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi   &uart3 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart3>; assigned-clocks = <&clk IMX8MM_CLK_UART3>; assigned-clock-parents = <&clk IMX8MM_SYS_PLL1_80M>; uart-has-rtscts; status = "okay"; }; + &uart4 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_uart4>; + assigned-clocks = <&clk IMX8MM_CLK_UART4>; + assigned-clock-parents = <&clk IMX8MM_SYS_PLL1_80M>; + status = "okay"; + }; ********************** pinctrl_uart3: uart3grp { fsl,pins = < MX8MM_IOMUXC_ECSPI1_SCLK_UART3_DCE_RX 0x140 MX8MM_IOMUXC_ECSPI1_MOSI_UART3_DCE_TX 0x140 MX8MM_IOMUXC_ECSPI1_SS0_UART3_DCE_RTS_B 0x140 MX8MM_IOMUXC_ECSPI1_MISO_UART3_DCE_CTS_B 0x140 >; }; + pinctrl_uart4: uart4grp { + fsl,pins = < + MX8MM_IOMUXC_UART4_RXD_UART4_DCE_RX 0x140 + MX8MM_IOMUXC_UART4_TXD_UART4_DCE_TX 0x140 + >; + };   iMX8MP-EVK   https://github.com/nxp-imx/imx-atf/blob/lf_v2.6/plat/imx/imx8m/imx8mp/imx8mp_bl31_setup.c   imx8mp_bl31_setup.c   RDC_MDAn(RDC_MDA_M7, DID1), RDC_MDAn(RDC_MDA_LCDIF, DID2), RDC_MDAn(RDC_MDA_LCDIF2, DID2), RDC_MDAn(RDC_MDA_HDMI_TX, DID2), /* peripherals domain permission */ + RDC_PDAPn(RDC_PDAP_UART4, D0R | D0W), RDC_PDAPn(RDC_PDAP_UART2, D0R | D0W), RDC_PDAPn(RDC_PDAP_WDOG1, D0R | D0W), RDC_PDAPn(RDC_PDAP_RDC, D0R | D0W | D1R),   Device tree configurations for iMX8MP-EVK   iMX8MP-EVK.dts   https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/arch/arm64/boot/dts/freescale/imx8mp-evk.dts   &uart3 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart3>; assigned-clocks = <&clk IMX8MP_CLK_UART3>; assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_80M>; fsl,uart-has-rtscts; status = "okay"; }; + &uart4 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_uart4>; + assigned-clocks = <&clk IMX8MP_CLK_UART4>; + assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_80M>; + status = "okay"; + }; ************************************ pinctrl_uart3: uart3grp { fsl,pins = < MX8MP_IOMUXC_ECSPI1_SCLK__UART3_DCE_RX 0x140 MX8MP_IOMUXC_ECSPI1_MOSI__UART3_DCE_TX 0x140 MX8MP_IOMUXC_ECSPI1_SS0__UART3_DCE_RTS 0x140 MX8MP_IOMUXC_ECSPI1_MISO__UART3_DCE_CTS 0x140 >; }; + pinctrl_uart4: uart4grp { + fsl,pins = < + MX8MP_IOMUXC_UART4_RXD__UART4_DCE_RX 0x140 + MX8MP_IOMUXC_UART4_TXD__UART4_DCE_TX 0x140 + >; + };     After compiling the image with the changes previously shown, we obtained this result:      

i.MX93 DDR stress test tool is different with previous i.MX tool. This Chinese article describe how to debug i.MX93 DDR and introduce DDR config tool usage.

GUI Guider version: 1.6.0 LVGL version: v8.3.5 Host software requirements: Ubuntu 20.04, Ubuntu 22.04 or Debian 12 Hardware requirements: Evaluation Kit for the i.MX 93 Applications Processor. (i.MX 93 Evaluation Kit | NXP Semiconductors) On this guide we will use the IMX-MIPI-HDMI accessory board to connect the iMX93 with a HDMI Monitor. (IMX-MIPI-HDMI Product Information|NXP) This board is usually provided with the iMX8M Mini and the iMX8M Nano.  Steps: 1. Copy your project from the folder GUI-Guider-Projects to your Linux PC.  2. Build an image for iMX93 using The Yocto Project.    a. Based on iMX Yocto Porject Users Guide set directories and download the repo $ mkdir imx-bsp-6.1.1-1.0.0 $ cd imx-bsp-6.1.1-1.0.0 $ repo init -u https://github.com/nxp-imx/imx-manifest -b imx-linux-langdale -m imx-6.1.1-1.0.0.xml $ repo sync Use distro fsl-imx-xwayland and select machine imx93evk and use this commnad with a build folder name: $ MACHINE=imx93evk DISTRO=fsl-imx-xwayland source ./imx-setup-release.sh - b bld-imx93evk b. Use bitbake command to start the build process. Also, add the -c populate_sdk to get the toolchain. $ bitbake imx-image-multimedia -c populate_sdk  c. Install the Yocto toolchain located on <build-folder>/tmp/deploy/sdk/.  $ sudo sh ./fsl-imx-xwayland-glibc-x86_64-imx-image-multimedia-armv8a-imx93evk-toolchain-6.1-langdale.sh d. Install ninja utility on the build host $ sudo apt install ninja-build e. For Ubuntu 20.04 and Ubuntu 22.04, copy the lv_conf.h file from lvgl-simulator to lvgl $ cp lvgl-simulator/lv_conf.h lvgl/ f. Change the interpreter on build.sh from #!/bin/sh to #!/bin/bash. This is an important step! g. Then, enter to linux folder and use the following commands to make build.sh executable $ dos2unix build.sh $ chmod +x build.sh h. Execute the build.sh $ ./build.sh i. Copy the binary to the iMX93 using a USB or SCP.  2. On the target iMX93 follow these steps. a. On Uboot, use fatls interface device:partition fatls mmc 0:1 (Device 0 : Partition 1) With this command, we will be able to list device tree files. => fatls mmc 0:1 b. Select imx93-11x11-evk-rm67199.dtb and use the command editenv fdtfile  => editenv fdtfile Output example edit: imx93-11x11-evk-rm67199.dtb c. In edit command line put the selected device tree .dtb d. Use saveenv command to save environment and continue with the boot process. e. Finally, run the GUI Application $ ./gui_guider&   I hope this article will be helpful. Best regards, Brian.

Installing the new release (Ubuntu 22.04) was detected some NXP boards as iMX8MNEVK, iMX8MM-EVK, iMX8MP-EVK and iMX8ULP-EVK had an issue with the WIFI module that basically it does not initialize at boot. Remember, the supported WIFI modules in Ubuntu 22.04 in the EVKs are the following:       • NXP 88W8987       • NXP 88W9098       • NXP 88W8997       • NXP IW416       • NXP 88W8801       • NXP IW612 To initialize the WIFI module of NXP EVKs in Ubuntu 22.04 you can set the following command in console:   sudo modprobe moal mod_para=nxp/wifi_mod_para.conf   That command find the correct driver for our WIFI module and then initialize it, but this only works when Ubuntu is working and if you reset the EVK you need to set the command again.   The definitive solution is create a custom startup script as a service:   Step 1: Go to etc/systemd/system   cd etc/systemd/system   Step 2: In this directory create a new file with the name of your preference but the extension must be .service. You can do it with nano or vim: sudo nano or sudo vim   The file must contain: [Unit] Description=”Wifi Start” [Service] ExecStart=sudo modprobe moal mod_para=nxp/wifi_mod_para.conf [Install] WantedBy=multi-user.target   Now save the file, in my case the name was wifi_start.service.   Step 3: Now we need to enable the script in the startup/boot sequence following the command: sudo systemctl enable wifi_start.service   Remember in wifi_start.service is the name as you saved your file.   Finally, each time you boot your board, the WIFI module will initialize automatically.   Boards tested: iMX8MN (With WIFI module NXP 88W8987) iMX8MM (With WIFI module NXP 88W8987) iMX8MP (With WIFI module NXP 88W8997) iMX8ULP (With WIFI module NXP IW416)  

On i.MX8MP EVK, image is downloaded into eMMC/SD via OTG1, if customer wants to enable USB OTG2 on i.MX8MP for uuu tool. Pls find modification as attached.

BSP: L5.15.5_1.0.0   Platform: i.MX8MPlus EVK   1. Parameter preparation For more parameter calculation, please refer to: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/iMX-8M- Mini-Register-Programming-Aid-DRAM-PLL-setting/ta-p/111209  For 1866MHz LPDDR4, we need a DRAM PLL size of 933MHz. The PLL dividing parameters are: m=622,p=16,s=0, k=0.   2. Calibration and stress test with DDR Tool 2.1 Creating a test script for 1866MHz Here we copy the script from another file (e.g. 2000MHz) and modify the contents of the script.   2.2 Modify the script to adapt to 1866MHz 2.3 Download the test script After selecting the ddr script we created, click on the download button   2.4 Calibrating the stress test Set the core clock of the chip's cpu to 1.2GHz, then click the Calibration button to calibrate, then click Gen Code to generate the lpddr4_timing.c file. Set the start frequency to 1866MHz for the stress test.   2.5 Modify lpddr4_timing.c We need to modify the generated lpddr4_timing.c file to change the maximum speed to 3732MTS.   3. SPL patch After getting the correct lpddr4_timing.c file, the SPL code also needs to be modified to add support for the 933MHz DRAM PLL. diff --git a/arch/arm/mach-imx/imx8m/clock_imx8mm.c b/arch/arm/mach-imx/imx8m/clock_imx8mm.c index e39f238fdf...5622a6334e 100644 --- a/arch/arm/mach-imx/imx8m/clock_imx8mm.c +++ b/arch/arm/mach-imx/imx8m/clock_imx8mm.c @@ -55,6 +55,7 @@ static struct imx_int_pll_rate_table imx8mm_fracpll_tbl[] = { PLL_1443X_RATE(650000000U, 325, 3, 2, 0), PLL_1443X_RATE(600000000U, 300, 3, 2, 0), PLL_1443X_RATE(594000000U, 99, 1, 2, 0), + PLL_1443X_RATE(933000000U, 622, 16, 0, 0), PLL_1443X_RATE(400000000U, 400, 3, 3, 0), PLL_1443X_RATE(2660000U, 266, 3, 3, 0), PLL_1443X_RATE(167000000U, 334, 3, 4, 0), diff --git a/drivers/ddr/imx/imx8m/ddrphy_utils.c b/drivers/ddr/imx/imx8m/ddrphy_utils.c index 326b92d784..ebd005bc2b 100644 --- a/drivers/ddr/imx/imx8m/ddrphy_utils.c +++ b/drivers/ddr/imx/imx8m/ddrphy_utils.c @@ -117,6 +117,10 @@ void ddrphy_init_set_dfi_clk(unsigned int drate) dram_pll_init(MHZ(1000)); dram_disable_bypass(); break; + case 3732: + dram_pll_init(MHZ(933)); + dram_disable_bypass(); + break; case 3200: dram_pll_init(MHZ(800)); dram_disable_bypass();   4. Test results   Reference blog. DDR Tool: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-8M-Family-DDR-Tool-Release/ta-p/1104467  RPA: https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-8MPlus-m865S-DDR-Register-Programming-Aids-RPA/ta-p/1235352 

 This article instruct customer how to develop on i.MX8MP NPU and how to debug performance. 

In some cases, i.MX board connect to different module. It has very tiny changes, such as just one gpio different driver strength. We can build an entire new software to handle this requirement. Here we introduce another way, using u-boot to modify the device tree(dtb) at runtime.   Here is u-boot fdt command for  How to use gpio-hog demo https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-to-use-gpio-hog-demo/ta-p/1317709   run loadfdt fdt addr ${fdt_addr_r} fdt print /soc/bus/pinctrl/uart3grp fdt rm /soc/bus/pinctrl/uart3grp fdt print serial2 fdt set serial2 status disabled fdt print serial2 fdt print gpio4 fdt resize fdt mknode gpio4 gpio_hog_demo fdt set gpio4/gpio_hog_demo gpio-hog fdt set gpio4/gpio_hog_demo gpios <7 0> fdt set gpio4/gpio_hog_demo output-high fdt print gpio4 run mmcargs run loadimage booti ${loadaddr} - ${fdt_addr_r} root@imx8mmevk:~# cat /sys/kernel/debug/gpio gpiochip0: GPIOs 0-31, parent: platform/30200000.gpio, 30200000.gpio: gpio-5 ( |PCIe DIS ) out hi gpio-13 ( |ir-receiver ) in hi IRQ ACTIVE LOW gpio-15 ( |cd ) in hi IRQ ACTIVE LOW gpiochip1: GPIOs 32-63, parent: platform/30210000.gpio, 30210000.gpio: gpio-38 ( |? ) out hi gpio-42 ( |reset ) out lo ACTIVE LOW gpio-51 ( |regulator-usdhc2 ) out lo gpiochip2: GPIOs 64-95, parent: platform/30220000.gpio, 30220000.gpio: gpio-80 ( |status ) out hi gpiochip3: GPIOs 96-127, parent: platform/30230000.gpio, 30230000.gpio: gpio-117 ( |PCIe reset ) out hi gpiochip4: GPIOs 128-159, parent: platform/30240000.gpio, 30240000.gpio: gpio-135 ( |gpio_hog_demo ) out hi gpio-141 ( |spi1 CS0 ) out hi ACTIVE LOW gpio-149 ( |wlf,mute ) out hi ACTIVE LOW root@imx8mmevk:~# [ 33.758914] VSD_3V3: disabling dtc_utils-v1.6.1-win-x86_64.zip by msys2   

Header 1 Header 2 Video rendering gst-launch videotestsrc ! mfw_v4lsink Audio rendering gst-launch audiotestsrc ! alsasink WAV Audio rendering gst-launch filesrc location=test.wav ! wavparse ! alsasink Video rendering selecting caps gst-launch videotestsrc ! capsfilter name='video/x-raw-yuv,format=(fourcc)I420' ! mfw_v4lsink gst-launch videotestsrc ! 'video/x-raw-yuv,format=(fourcc)I420' ! mfw_v4lsink

This is the procedure and patch to set up Ubuntu 12.04 64bit Linux Host PC and building i.MX28 L2.6.35_1.1.0_130130.  It has been tested to build GNOME profile and with FSL Standard MM codec. A) Basic Requirement: Set up the Linux Host PC using ubuntu-12.04.3-desktop-amd64.iso Make sure the previous LTIB installation and the /opt/freescale have been removed B) Installed the needed packages to the Linux Host PC $ sudo apt-get update $ sudo apt-get install gettext libgtk2.0-dev rpm bison m4 libfreetype6-dev $ sudo apt-get install libdbus-glib-1-dev liborbit2-dev intltool $ sudo apt-get install ccache ncurses-dev zlib1g zlib1g-dev gcc g++ libtool $ sudo apt-get install uuid-dev liblzo2-dev $ sudo apt-get install tcl dpkg $ sudo apt-get install asciidoc texlive-latex-base dblatex xutils-dev $ sudo apt-get install texlive texinfo $ sudo apt-get install ia32-libs libc6-dev-i386 lib32z1 $ sudo apt-get install uboot-mkimage $ sudo apt-get install scrollkeeper $ sudo apt-get install gparted $ sudo apt-get install nfs-common nfs-kernel-server $ sudo apt-get install git-core git-doc git-email git-gui gitk $ sudo apt-get install meld atftpd C) Unpack and install the LTIB source package and assume done on the home directory: $ cd ~ $ tar -zxvf L2.6.35_1.1.0_130130_source.tar.gz $ ./L2.6.35_1.1.0_130130_source/install After that, you will find ~/ltib directory created D) Apply the patch to make L2.6.35_1.1.0 could be installed and compiled on Ubuntu 12.04 64bit OS $ cd ~/ltib $ git apply 0001_make_L2.6.35_1.1.0_130130_compile_on_ubuntu_12.04_64bit_OS.patch a) The patch modifies the following files:    dist/lfs-5.1/base_libs/base_libs.spec    dist/lfs-5.1/lkc/lkc.spec    dist/lfs-5.1/mux_server/mux_server.spec    dist/lfs-5.1/ncurses/ncurses.spec b) Add the following files to the pkgs directory:    pkgs/lkc-1.4-lib.patch    pkgs/lkc-1.4-lib.patch.md5 E) Then, it is ready to proceed the rest of the LTIB env setup process: $ cd ~/ltib $ ./ltib -m config $ ./ltib Reference: L2.6.35_1.1.0_130130_docs/doc/mx28/Setting_Up_LTIB_Host_on_Ubuntu_9_04.pdf https://community.freescale.com/docs/DOC-93394 https://community.freescale.com/message/332385#332385 https://community.freescale.com/thread/271675 https://community.freescale.com/message/360556#360556 scrollkeeper is for the gnome-desktop compilation NOTE: When compiling gstreamer, this warning was pop up.  Just ignore it seems okay.

The purpose of the document is to help customer setup development  environment of android BSP, The document includes the following contents: 1.Setup environment for compiling android BSP source code 2. Setup tftp and NFS environment for android development 3. Common Steps of Porting android  to customized borad ( L3.0.35 kernel) Note: (1) ubuntu version is suitable for 12.04/14.04/15.04 (2) android BSP version is 4.2.2 / 4.3 / 4.4.2  If cusotmer is using android5.1.1 / android 6.0 or above, The way of porting kernel should be focused on adjusting device tree. (3)Each andoid BSP has its own MFG tools version. User should pay attention to this, don't use wrong version of MFG Tools. NXP TIC team Weidong Sun

Kernel provides mtdoops to dump kmsg to MTD device, but MMC card is not a MTD device. We can let user-space program to execute the write operation to dump kmsg into block storage. The sample code is below. kernel space -- #include <linux/kernel.h> #include <linux/module.h> #include <linux/console.h> #include <linux/vmalloc.h> #include <linux/seq_file.h> #include <linux/workqueue.h> #include <linux/sched.h> #include <linux/wait.h> #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/kmsg_dump.h> #include <linux/proc_fs.h> static struct kmsg_dumper dump; static struct proc_dir_entry *my_proc; static int is_panic = 0; static int my_proc_show(struct seq_file *m, void *v) {     seq_printf(m, "%d", is_panic);     return 0; } static int my_proc_open(struct inode *inode, struct file *file) {     return single_open(file, my_proc_show, NULL); } static const struct file_operations my_proc_ops = {     .open        = my_proc_open,     .read        = seq_read,     .llseek        = seq_lseek,     .release    = single_release, }; static void oops_do_dump(struct kmsg_dumper *dumper,         enum kmsg_dump_reason reason, const char *s1, unsigned long l1,         const char *s2, unsigned long l2) {     int i;     printk("### [%s:%d] reason = %d\n", __func__, __LINE__, reason);     is_panic = 1;     for (i = 0;i < 10; i++)         msleep(1000);     printk("### [%s:%d] should be done\n", __func__, __LINE__); } static int __init my_oops_init(void) {     int err;     dump.dump = oops_do_dump;     err = kmsg_dump_register(&dump);     if (err) {         printk(KERN_ERR "oops: registering kmsg dumper failed, error %d\n", err);         return -EINVAL;     }     my_proc = proc_create("dump_tester", 0, NULL, &my_proc_ops);     return 0; } static void __exit my_oops_exit(void) {     printk("### [%s:%d]\n", __func__, __LINE__);     if (my_proc)         remove_proc_entry( "dump_tester", NULL);     kmsg_dump_unregister(&dump); } module_init(my_oops_init); module_exit(my_oops_exit); MODULE_LICENSE("GPL"); User space -- #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> #include <fcntl.h> #include <poll.h> #define BUF_LEN 40960 void main(int argc, char **argv) {     char tmp = 'X';     char buf[BUF_LEN];     int fd_src, fd_trg;     int fd = open("/proc/dump_tester", O_RDONLY, 0);     while(1) {         lseek(fd, 0, SEEK_SET);         read(fd, &tmp, 1);         //printf("### [%s:%d] ==> '%c'\n", __FUNCTION__, __LINE__, tmp);         if (tmp == '1') {             fd_src = open("/proc/kmsg", O_RDONLY, 0);             fd_trg = open("/dev/block/mmcblk0p6",  O_RDWR, 0);             memset(buf, 0, BUF_LEN);             write(fd_trg, buf, BUF_LEN);             lseek(fd_trg, 0, SEEK_SET);             read(fd_src, buf, BUF_LEN);             write(fd_trg, buf, BUF_LEN);             close(fd_src);             close(fd_trg);             sleep(1);             printf("### dump panic log into %s\n", "/dev/block/mmcblk0p6");             break;         }         sleep(1);     }     close(fd); }

The solution works when I use mx53_loco bsp. Modify u-boot and kernel, keep the same. Then you may find you can't login into the system regardless of whatever you input after freescale login: It confused me for a long time. If you  also met this problem,try to check the iomux-mx53.h(linux/arch/arm/plat-mxc/include/mach/). #define _MX53_PAD_PATA_DIOW__UART1_TXD_MUX   IOMUX_PAD(the fourth argument 0x878 should be changed to 0x0) I think this is a small bug in header files. Haifeng

This patch release is target for LPDDR2 ( dual channels in interleave mode ) support on i.MX6DL platform. Two patches are prepared to modify u-boot and kernel in order to have correct DRAM init sequence, 400MHz & 24MHz frequency switching and suspend/resume support. The patches are not fully verified. It is provided as reference for customer to enable their i.MX6DL board with LPDDR2. Customization and Testing is needed by customer. We need to remind some points here: MMDC_MDCFG3LP in 24MHz need to increase the margin ( 0x40222 -> 0x80555 ) in order to pass the OS frequency switch stress test. We are identifying the reason but this workaround is working fine and included to the patch. Code changes in kernel is prepared so that it is compatible to DDR3. In other words, the DDR type will be detected and a correct handling will be done for LPDDR2 and DDR3. In LPDDR2 system, we can't put SDQ pin into LPM during suspend. Otherwise, the system cannot resume. Dual channels in fix mapping mode is not recommended to use.

Uploading the i.MX 6 Linux Reference Manual here after being un-able to find it on Google or on i.MX6 product page.

Question: What’s the best way to rotate a MX6 image 90 degrees, thought the IPU correct? IPU is limited to 1024x1024. Apparently we don’t support frame buffer rotation in the IPU, so we have to use some middleware. I know that Android’s surface flinger uses the GPU but do you know what we can use in Linux that uses H/W acceleration also? It looks look like X-server can rotate only when the Vivante driver is not  loaded, which means the hardware is not implementing rotations. Answer: it should be possible to split the picture into two halves and rotate them separately. Well, two halves if you can reduce the line count to 1024 … otherwise it would be 4 rotates. X11 Xrandr will be implemented on GPU sometime this year. It's in the R&D queue but as low priority. They could use GC320 low level API to rotate (if they use linux frame buffer). It implies a blit but it would be done by GC320 they will probably need to use virtualFB too. The API documentation is the BSP documentation (iMX6.2D.API.pdf) Attached a simple source using the 2D low level API. VirtualFB: https://community.freescale.com/message/289198

Starting from $52, the VAR-SOM-MX6 sets the bar for unparalleled design flexibility. The VAR-SOM-MX6 ensures scalable and simplified development, while also extending the product lifecycle. Thanks to four CPU core assembly options, customers can apply a single System on Module in a broad range of applications to achieve short time-to-market for their current innovations, while still accommodating potential R&D directions and marketing opportunities.     VAR-SOM-MX6 CPU: Freescale iMX6 Key features include: Freescale i.MX6 1.2GHz Quad / Dual / Single core Cortex-A9       2GB DDR3, 1GB SLC NAND Flash       Full HD 1080p video encoding/decoding capability       Vivante GPU providing 2D/3D acceleration       Simultaneous multiple display support       Gigabit Ethernet       TI WiLink™ 6.0 single-chip connectivity solution (Wi-Fi, Bluetooth®)       PCI-Express 2.0, S-ATA 3.0       Camera interface       USB 2.0: Host, OTG       Audio In/Out       Dual CAN Bus This versatile solution's -40 to 85°C temperature range and Dual CAN support is ideal for industrial applications, while 1080p video and graphics accelerations make it equally suitable for intensive multimedia applications. The impressive scalability of the VAR-SOM-MX6 satisfies the needs of the most demanding future application requirements whether faster processing power, enhanced algorithms or improved graphics and video performance to name just a few. The VAR-SOM-MX6 is an all-round solution with broad connectivity and sophisticated video and acceleration graphic capabilities, delivering a range of middle to high end assembly options all from the same product. For more details, please see VAR-SOM-MX6 CPU: Freescale iMX6

Hi All, The new i.MX 6 Q/D/DL/S/SL L3.0.35_4.1.0 GA release is now available on the http://www.freescale.com/site. ·         Files available                                   # Name Description 1 L3.0.35_4.1.0_LINUX_DOCS i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite Linux BSP   Documentation. Includes Release Notes, Reference Manual, User guide. API   Documentation 2 L3.0.35_4.1.0_LINUX_MMDOCS i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite  Linux Multimedia Codecs Documentation.   Includes CODECs Release Notes and User's Guide 3 L3.0.35_4.1.0_SOURCE_BSP i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite Linux BSP   Source Code Files 4 L3.0.35_4.1.0_MM_CODECS i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite  Linux Multimedia Codecs Sources 5 L3.0.35_4.1.0_AACP_CODECS i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite  Linux AAC Plus Codec 6 L3.0.35_4.1.0_DEMO_IMAGE_BSP i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite  Linux Binary Demo Files 7 L3.0.35_4.1.0_UBUNTU_RFS_BSP i.MX   6Quad, i.MX 6Dual, i.MX 6DualLite, i.MX 6Solo and i.MX 6Sololite  Linux File System for the Ubuntu Images 8 i.MX_6D/Q_Vivante_VDK_146_Tools Set   of applications for the Linux L3.0.35_4.1.0 BSP, designed to be used by   graphics application developers to rapidly develop and port graphics   applications. Includes applications, GPU Driver with vprofiler enabled and   documentation. 9 IMX_6DL_6S_MFG_TOOL Tool   and documentation for downloading OS images to the i.MX 6DualLite and i.MX   6Solo. 10 IMX_6DQ_MFG_TOOL Tool   and documentation for downloading OS images to the i.MX 6Quad and i.MX 6Dual. 11 IMX_6SL_MFG_TOOL Tool   and documentation for downloading OS images to the i.MX 6Sololite. ·         Target HW boards o   i.MX 6Quad SABRE-SDP o   i.MX 6Quad SABRE-SDB o   i.MX 6Quad SABRE-AI o   i.MX 6DualLite SABRE-SDP o   i.MX 6DualLite SABRE-AI o   i.MX 6SL EVK ·         New features o   BSP New Features on i.MX 6D/Q, i.MX 6DL/S and MX 6SL: §  HDCP §  CEC §  GPU4.6.9p12 §  Audio playback IRAM/SDMA §  V4L capture resize on MX6SL §  MX6DQ disable the double line fill feature of PL310 ·         Known issues o   For known issues and limitations please consult the release notes.