Re: [RFC 7/8] fpga-region: add sysfs interface

From: Anatolij Gustschin <agust@denx.de>
To: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Alan Tull <delicious.quinoa@gmail.com>,
	Moritz Fischer <moritz.fischer@ettus.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-fpga@vger.kernel.org
Subject: Re: [RFC 7/8] fpga-region: add sysfs interface
Date: Wed, 15 Feb 2017 22:20:53 +0100	[thread overview]
Message-ID: <20170215222053.725145a5@crub> (raw)
In-Reply-To: <20170215180612.GB3317@obsidianresearch.com>

Hi Jason,

On Wed, 15 Feb 2017 11:06:12 -0700
Jason Gunthorpe jgunthorpe@obsidianresearch.com wrote:
...
>The kernel could detect the bitfile starts with 'Linux_FPGA_BIT/1.0\n'
>and then proceed to decode the header providing compat with the
>current scheme.
>
>This is usually the sort of stuff I'd punt to userspace, but since the
>kernel is doing request_firmware it is hard to see how that is an
>option in this case...

Interesting. We have a requirement that the complete history of FPGA
configurations (basic configuration and the sequence of following
partial reconfigurations) should be readable from FPGA manager
framework on request. Each bitfile is associated with meta-data
and one should be able to read this meta-data back for complete
reconfiguration chain. When the kernel decodes a header, it could
optionally store the data and allow to read it back on request.

Thanks,
Anatolij