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Date:   Mon, 31 Oct 2022 00:04:17 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     "David E. Box" <david.e.box@linux.intel.com>,
        nirmal.patel@linux.intel.com, jonathan.derrick@linux.dev,
        lorenzo.pieralisi@arm.com, hch@infradead.org, kw@linux.com,
        robh@kernel.org, bhelgaas@google.com, michael.a.bottini@intel.com,
        rafael@kernel.org, me@adhityamohan.in, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V7 3/4] PCI: vmd: Add vmd_device_data
Message-ID: <Y19zcYqxk7LcGQfG@infradead.org>
References: <20221025004411.2910026-4-david.e.box@linux.intel.com>
 <20221028191308.GA903098@bhelgaas>
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On Fri, Oct 28, 2022 at 02:13:08PM -0500, Bjorn Helgaas wrote:
> It looks like these devices come in families where several device IDs
> share the same features.  I think this would be more readable if you
> defined each family outside this table and simply referenced the
> family here.  E.g., you could do something like:
> 
>   static struct vmd_device_data vmd_v1 = {
>     .features = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
> 		VMD_FEAT_HAS_BUS_RESTRICTIONS |
> 		VMD_FEAT_OFFSET_FIRST_VECTOR,
>   };
> 
>   {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
>     .driver_data = (kernel_ulong_t) &vmd_v1,
> 
> Then you can add VMD_FEAT_BIOS_PM_QUIRK and the .ltr value in one place
> instead of repeating it a half dozen times.

I wonder why we need the ltr field at all.  For those that set it
is always the same value, so it could just be a quirk flag to set it.

Tat being said I think thegrouping makes a lot of sense, but I'd just
do it with a #define for the set of common quirk flags.