Bug 234055 - PL011 UART driver unable to change baudrate when booted via u-boot
Summary: PL011 UART driver unable to change baudrate when booted via u-boot
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: arm (show other bugs)
Version: CURRENT
Hardware: arm64 Any
: --- Affects Some People
Assignee: freebsd-arm (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2018-12-16 12:17 UTC by Jorge Schrauwen
Modified: 2018-12-16 12:17 UTC (History)
0 users

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Description Jorge Schrauwen 2018-12-16 12:17:54 UTC
After a long few months trying to figure this out...

It looks like the PL011 UART driver is unable to set a baudrate when booted via u-boot. My understanding of the code is poor but it looks like it only works for x86 BIOS/EFI booted systems.

This seems like something that might be useful for people running HAT's on raspberry pi's or other ARM boards.

Currently the baudrate can be set using u-boot by adding

init_baudrate="9600" to /boot/msdos/config.txt but it FreeBSD is unable to change it. 

It would be nice to have baudrate setting implemented eventually... but at least now there is a ticket for other people having this problem.