Date: Mon, 12 Dec 2016 16:52:15 -0600
From: Patrick Williams <patrick@stwcx.xyz>
To: Joel Stanley <joel@jms.id.au>
Cc: eajames.ibm@gmail.com, OpenBMC Maillist <openbmc@lists.ozlabs.org>,
 Christopher Bostic <christopher.lee.bostic@gmail.com>,
 "Edward A. James" <eajames@us.ibm.com>
Subject: Re: [RFC linux 1/2] drivers: fsi: Add SBE client device driver
Message-ID: <20161212225215.GA5150@heinlein.lan>
References: <1481064330-20757-1-git-send-email-eajames.ibm@gmail.com>
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On Mon, Dec 12, 2016 at 03:26:46PM +1100, Joel Stanley wrote:
> Lets have a discussion abut what client drivers we will need to have
> in the kernel for FSI.
>=20
> We should consider only creating kernel drivers when the code cannot
> live in userspace. This would mean situations where exclusive access
> to some part of the address space is required (SCOMs), when the
> sequence of reads/writes are timing critical, or when there are IRQs
> involved.
>=20
> For cases where we're simply writing or reading values to the register
> CFAM address space, writing userspace code should be sufficient.
>=20
> What do you think about this approach?

I'm pretty sure there is some layering going on here.  SBE driver uses
FSI, OCC driver (on P9) uses SBE.  We can't get an hwmon OCC driver
without this SBE driver.

Eddie, can you confirm?

--=20
Patrick Williams

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