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Date:   Tue, 25 Jul 2023 18:30:46 +0200
From:   Lukas Wunner <lukas@wunner.de>
To:     Alistair Francis <alistair23@gmail.com>
Cc:     bhelgaas@google.com, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Alistair Francis <alistair.francis@wdc.com>
Subject: Re: [PATCH] PCI/DOE: Expose the DOE protocols via sysfs
Message-ID: <20230725163046.GA23990@wunner.de>
References: <20230725035755.2621507-1-alistair.francis@wdc.com>
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On Tue, Jul 25, 2023 at 01:57:55PM +1000, Alistair Francis wrote:
> The PCIe 6 specification added support for the Data Object Exchange (DOE).
> When DOE is supported the Discovery Data Object Protocol must be
> implemented. The protocol allows a requester to obtain information about
> the other DOE protocols supported by the device.
> 
> The kernel is already querying the DOE protocols supported and cacheing
> the values. This patch exposes the values via sysfs. This will allow
> userspace to determine which DOE protocols are supported by the PCIe
> device.

Just dumping the list of supported protocols into dmesg might be simpler,
unless you intend to add mechanisms to actually use certain DOE mailboxes
from user space or expose the information in lspci.  Do have plans for
either of that or what's the motivation to use sysfs?

I think I'd rather want everything in doe.c (#ifdef'ed to CONFIG_SYSFS)
and only make dev_attr_doe_proto public.

Thanks,

Lukas