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Subject: Re: [PATCH v4 19/23] drivers/fsi: Add GPIO based FSI master
From: Benjamin Herrenschmidt <benh@au1.ibm.com>
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Date: Mon, 10 Apr 2017 07:55:37 +1000
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On Mon, 2017-04-10 at 07:53 +1000, Benjamin Herrenschmidt wrote:
> FYI. pdbg in userspace operates without any  delays in practice, the
> overhead between the various load/store instructions seems
> sufficient.
> 
> The only delay that's needed is when going through the FSI2PIB (to do
> SCOMs) where it seems like back-2-back accesses can be problematic.

Note: This isn't an objection to merging the patches. We can look at
doing an improved backend later.

Cheers,
Ben.