1Boundary Devices SABRE Lite (``sabrelite``) 2=========================================== 3 4Boundary Devices SABRE Lite i.MX6 Development Board is a low-cost development 5platform featuring the powerful Freescale / NXP Semiconductor's i.MX 6 Quad 6Applications Processor. 7 8Supported devices 9----------------- 10 11The SABRE Lite machine supports the following devices: 12 13 * Up to 4 Cortex-A9 cores 14 * Generic Interrupt Controller 15 * 1 Clock Controller Module 16 * 1 System Reset Controller 17 * 5 UARTs 18 * 2 EPIC timers 19 * 1 GPT timer 20 * 2 Watchdog timers 21 * 1 FEC Ethernet controller 22 * 3 I2C controllers 23 * 7 GPIO controllers 24 * 4 SDHC storage controllers 25 * 4 USB 2.0 host controllers 26 * 5 ECSPI controllers 27 * 1 SST 25VF016B flash 28 29Please note above list is a complete superset the QEMU SABRE Lite machine can 30support. For a normal use case, a device tree blob that represents a real world 31SABRE Lite board, only exposes a subset of devices to the guest software. 32 33Boot options 34------------ 35 36The SABRE Lite machine can start using the standard -kernel functionality 37for loading a Linux kernel, U-Boot bootloader or ELF executable. 38 39Running Linux kernel 40-------------------- 41 42Linux mainline v5.10 release is tested at the time of writing. To build a Linux 43mainline kernel that can be booted by the SABRE Lite machine, simply configure 44the kernel using the imx_v6_v7_defconfig configuration: 45 46.. code-block:: bash 47 48 $ export ARCH=arm 49 $ export CROSS_COMPILE=arm-linux-gnueabihf- 50 $ make imx_v6_v7_defconfig 51 $ make 52 53To boot the newly built Linux kernel in QEMU with the SABRE Lite machine, use: 54 55.. code-block:: bash 56 57 $ qemu-system-arm -M sabrelite -smp 4 -m 1G \ 58 -display none -serial null -serial stdio \ 59 -kernel arch/arm/boot/zImage \ 60 -dtb arch/arm/boot/dts/imx6q-sabrelite.dtb \ 61 -initrd /path/to/rootfs.ext4 \ 62 -append "root=/dev/ram" 63 64Running U-Boot 65-------------- 66 67U-Boot mainline v2020.10 release is tested at the time of writing. To build a 68U-Boot mainline bootloader that can be booted by the SABRE Lite machine, use 69the mx6qsabrelite_defconfig with similar commands as described above for Linux: 70 71.. code-block:: bash 72 73 $ export CROSS_COMPILE=arm-linux-gnueabihf- 74 $ make mx6qsabrelite_defconfig 75 76Note we need to adjust settings by: 77 78.. code-block:: bash 79 80 $ make menuconfig 81 82then manually select the following configuration in U-Boot: 83 84 Device Tree Control > Provider of DTB for DT Control > Embedded DTB 85 86To start U-Boot using the SABRE Lite machine, provide the u-boot binary to 87the -kernel argument, along with an SD card image with rootfs: 88 89.. code-block:: bash 90 91 $ qemu-system-arm -M sabrelite -smp 4 -m 1G \ 92 -display none -serial null -serial stdio \ 93 -kernel u-boot 94 95The following example shows booting Linux kernel from dhcp, and uses the 96rootfs on an SD card. This requires some additional command line parameters 97for QEMU: 98 99.. code-block:: none 100 101 -nic user,tftp=/path/to/kernel/zImage \ 102 -drive file=sdcard.img,id=rootfs -device sd-card,drive=rootfs 103 104The directory for the built-in TFTP server should also contain the device tree 105blob of the SABRE Lite board. The sample SD card image was populated with the 106root file system with one single partition. You may adjust the kernel "root=" 107boot parameter accordingly. 108 109After U-Boot boots, type the following commands in the U-Boot command shell to 110boot the Linux kernel: 111 112.. code-block:: none 113 114 => setenv ethaddr 00:11:22:33:44:55 115 => setenv bootfile zImage 116 => dhcp 117 => tftpboot 14000000 imx6q-sabrelite.dtb 118 => setenv bootargs root=/dev/mmcblk3p1 119 => bootz 12000000 - 14000000 120