TS-4900 U-boot changelog

U-boot release date	Changes
Jul-22-2014	Initial Release
Sep-24-2014	Instead of pressing any key during startup, now it requires Ctrl+C. This is to prevent any serial noise from stopping the board in u-boot. The board will now attempt to load /boot/boot.ub before continuing. This is intended for booting environments like QNX, android, and more that cannot use the standard boot arguments.
Nov-06-2014	Updated ddr calibration for new build (TS-4900 solo 800MHz industrial temp 1GB RAM) Enabled usb 5V by default for usb boot mechanism
Nov-19-2014	Updated to U-boot 2014.10 (from 2013.10) Functionally the same Included android boot image support Included fastboot support SATA boot fixes
Dec-01-2014	Added bbdetect command to 2014.10
Dec-05-2014	Ignored RPCERRORs from the UMNTALL RPC call after an NFS transaction. Not all nfs servers implement this and it should not invalidate the file transfer since it is just for state tracking on the server.
Jan-26-2014	Fixed USB 5V reset timing for boards with hubs. USB 5V is now disabled 500ms after OFF_BD_RESET is disabled. On older revs USB may not detect some peripherals if the USB 5V comes up before the hub is out of reset. Added "rcause" variable. This lets u-boot scripts make use of the reset cause in scripts. For example, if rcause is "POR" in the field, it may have experienced a brownout and an alternate kernel/os could be booted instead. If rcause is "WDOG" then either a reset or watchdog condition caused the reset. New "model" variable with "4900" or "7970", etc. This is so common usb blasters can be used and determine the model. new "rev" variable including "A" or "C". This is also now printed at startup.
Jan-29-2014	Included updates for REV C boards If I2C locks up, reset RTC FET for rare lockup. U-boot networking speed limited to 100Mb/s by default. Gigabit requires about 5 seconds to autonegotiate. 10/100Mb/s requires ~500ms. The common case being NFS booting which requires a 3-4MB kernel, 300kb of device tree, 100kb of fpga binary, gigabit only slows down booting. This does not disable gigabit for Linux.
Mar-12-2014	Fixed typo in RTC FET workaround Added EXT4 and FAT write support for Ubuntu Snappy Core
Jul-27-2015	Added fix for PCIe hang in Linux. Some of the GPR1 regs were not being reset after a reboot. U-boot will now reset these before going into Linux. This hang was not present on all CPUs, usually solo, and only if PCIe is enabled in the kernel.
Oct-07-2015	Corrected ice40 SPI MODE used during programming
Oct-14-2015	Added eth1addr mac address variable Added smsc95xx.macaddr=${eth1addr} to the default cmdline To use the new MAC address for the USB Ethernet on some carrier boards you need the latest kernel as of today to include this patch. Added sataboot command in default environment. Must be called manually or put in bootcmd to be used.
Dec-14-2015	Offboard SPI chip select is no longer asserted during FPGA programming.
Dec-21-2015	Increased drive strength for the Ethernet signals Removed smsx95xx parameter and switched to u-boot's device tree fixup to set mac for the second ethernet. This requires this u-boot and at least this kernel revision.
Mar-08-2016	Added REV D detection (not required for REV D support, just reporting). Improved I2C lockup recovery on startup.
Apr-05-2016	Added bmode command
May-18-2016	Improved FPGA programming reliability on new chips Shortened NFS timeout Made the nfs command not care about nfs mount/umount errors. This is optional in NFS and should not matter in u-boot. On our test servers (solaris and linux) this makes NFS much faster since we don't wait for a timeout after every single nfs command blocking on a nonexistent mount reply.
Oct-19-2016	Added simple POST test. This is not enabled by default so there is no behavior change unless the "post" command is called.
Apr-27-2017	Fixed USB OTG port's host mode
Mar-26-2017	Add support for SST26VF064BA, and IS25LP064A spi flashes
Mar-31-2020	Added support for the REV E hardware revision
Feb-10-2021	Improved fallback device trees for older TS-4900 hardware revisions