Changes between Initial Version and Version 1 of catalina/bootloader

Timestamp:

04/27/2026 11:51:51 PM (2 days ago)

Author:

Tim Harvey

Comment:

initial page

catalina/bootloader

@@ +1 @@
+[[PageOutline]]
+
+
+[=#u-boot]
+= Catalina U-Boot Bootloader
+Gateworks supports the U-Boot Bootloader for the Catalina product family.
+
+The purpose of a bootloader is to load the Linux kernel and execute it passing it configuration parameters such as an optional kernel command-line, an optional initial ramdisk filesystem, and a device-tree.
+
+The following items are supported in the Gateworks U-Boot for Catalina:
+ - i.MX95 ENETC Ethernet (port0, port1, port2)
+ - USB Host support
+  * USB Mass Storage
+  * USB Networking (for various adapters supported in U-Boot)
+ - eMMC (mmc dev 0)
+ - microSD (mmc dev 1)
+
+see [wiki:uboot] for more info
+
+
+== U-Boot Environment
+
+=== Default environment
+If you would like to modify the default environment you can edit the [https://github.com/Gateworks/u-boot/blob/v2026.04-catalina/board/gateworks/catalina/catalina.env catalina.env] in the Catalina BSP.
+
+=== Restoring defaults 
+The Catalina boot firmware default is build into the U-Boot binary. If you erase the version stored on the boot device it will be restored.
+
+To restore default bootloader environment variables:
+
+- At the "Hit any key to stop autoboot:" prompt press any key.
+- Execute the following command:
+{{{#!bash
+run env_erase && reset
+}}}
+
+
+[=#bootdevs]
+== Boot Devices
+The Catalina U-Boot Bootloader supports the following devices and partition types:
+ - eMMC
+ - microSD
+ - USB Mass Storage
+
+The U-Boot 'Standard Boot' is used for Catalina (vs the older legacy 'Generic Distro Config' used for previous product families):
+ - the default bootcmd will ultimately search for boot scripts on a set of bootable devices 
+ - the 'boot_targets' env variable dictates which devices are checked and in what order (ie 'mmc0 mmc1 usb')
+ - the 'boot_prefixes' env variable dictates what file prefixes are searched for a boot script
+
+Catalina boards always boot from the on-board eMMC device but once in the U-Boot environment you can load your Linux based OS from any boot media supported in U-Boot such as USB, microSD, network.
+
+[=#memmap]
+== Memory Mapping
+When working with boot firmware you are often dealing with choosing where to load in memory various components. Sometimes this is done by hard-coding addresses into U-Boot commands, using env variables, or hard coding them into the U-Boot build configuration files (ie binman node) or FIT image templates.
+
+Here is what we recommend for memory mapping on for the Catalina i.MX95 SoC:
+||= address   =||= var =||= Note =||
+|| 0x90400000  || kernel_comp_addr_r || CONFIG_TEXT_BASE ||
+|| 0x98400000  || loadaddr,kernel_addr_r || CONFIG_SYS_LOAD_ADDR ||
+|| 0xa0400000  || fdt_addr_r || area for loading fdt (128M above kernel) ||
+|| 0xa0500000  || scriptaddr || area for loading a boot script (1M above fdt) ||
+|| 0xa0580000  || ramdisk_addr_r || area for loading a ramdisk (512K above script) ||
+|| 0xd0000000  || || 1GB boundary ||