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Subject: Re: [PATCH edk2-platforms 0/5] Platform/RaspberryPi: fix serialportlib dependency hell
To: devel@edk2.groups.io
Cc: leif@nuviainc.com, pete@akeo.ie, andrey.warkentin@gmail.com
References: <20200505145029.29826-1-ard.biesheuvel@arm.com>
From: "Ard Biesheuvel" <ard.biesheuvel@arm.com>
Message-ID: <f2527eab-79c1-d60c-f670-22d57a514fdb@arm.com>
Date: Wed, 6 May 2020 18:16:53 +0200
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On 5/5/20 4:50 PM, Ard Biesheuvel wrote:
> This proposes an alternative approach to the issue described in
> https://github.com/raspberrypi/firmware/issues/1376.
> 
> Instead of fiddling with HobLib internals and relying on headers being
> included in the correct order, this replaces all DEBUG uses of SerialPortLib
> with an implementation that doesn't reprogram the UART at all (and so does
> not need to know the value of the base clock), and updates the two remaining
> users to query the firmware for the correct value before touching the h/w.
> 
> NOTE: build tested only.
> 
> Ard Biesheuvel (5):
>    Platform/RaspberryPi/DualSerialPortLib: split up to ease reuse
>    Platform/RaspberryPi: introduce DebugDualSerialPortLib
>    Platform/RaspberryPi: fix 16550 divisor calculation logic
>    Platform/RaspberryPi3: query firmware for 16550 input clock at boot
>    Platform/RaspberryPi: create DXE phase SerialPortLib version for RPi3
> 

I have pushed this as 11189124fbc2..644e223bb371 with Pete's ack, after 
making the changes as discussed in the individual replies.