Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH 11/12] ARM: dts: add support for Vybrid running on Cortex-M4 | Date | Wed, 17 Dec 2014 11:57:06 +0100 |
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On Tuesday 16 December 2014 23:19:08 Stefan Agner wrote: > On 2014-12-03 12:03, Arnd Bergmann wrote: > > On Wednesday 03 December 2014 01:12:10 Stefan Agner wrote:
> Just started looking in that a bit deeper and some question arose: > Afaik, earlycon need to be supported by the uart driver. The fsl_lpuart, > which is used for Vybrid's uart, does not support earlycon yet. However, > earlyprink already works (see ./arch/arm/include/debug/vf.S). I > understand that earlycon has the advantage of being able to be used on > multiplatform. But earlyprintk is working really early (e.g. before > locating the FDT), and it proved helpful for me when I started working > on that Cortex-M4 stuff. Should earlycon replace earlyprintk completely?
earlyprintk will stay around for debugging early boot problems, but with working earlycon support, there should no longer be a reason to enable it by default.
> Maybe, on Vybrid, since it would be a good platform for automated !MMU > testing, it would be nice to have earlycon which can be enabled in any > case and would provide output even something blows up quite early... But > I guess I would add earlycon support as part of a new patchset and just > drop earlyprintk here for now.
Yes, I think that would be good.
> > 64 hash table entries sounds extremely small, doesn't that impact > > performance? If you have 50MB of actual RAM available, I don't think > > you need that. > > Agreed. I copied that from EFM32 which is under much more memory > pressure...
Ok.
Arnd
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