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Message-ID: <3c9fa928-f416-3526-be23-12644d18db3b@linux.intel.com>
Date:   Sat, 11 Jun 2022 11:25:03 +0800
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Subject: Re: [PATCH v2 0/6] Configurable VLAN mode for NCSI driver
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To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Samuel Mendoza-Jonas <sam@mendozajonas.com>,
        "David S . Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        openbmc@lists.ozlabs.org
References: <20220610165940.2326777-1-jiaqing.zhao@linux.intel.com>
 <20220610130903.0386c0d9@kernel.org>
From:   Jiaqing Zhao <jiaqing.zhao@linux.intel.com>
In-Reply-To: <20220610130903.0386c0d9@kernel.org>
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On 2022-06-11 04:09, Jakub Kicinski wrote:
> On Sat, 11 Jun 2022 00:59:34 +0800 Jiaqing Zhao wrote:
>> Currently kernel NCSI driver only supports the "VLAN + non-VLAN" mode
>> (Mode #2), but this mode is an optional mode [1] defined in NCSI spec
>> and some NCSI devices like Intel E810 Network Adapter [2] does not
>> support that mode. This patchset adds a new "ncsi,vlan-mode" device
>> tree property for configuring the VLAN mode of NCSI device.
>>
>> [1] Table 58 - VLAN Enable Modes
>>     https://www.dmtf.org/sites/default/files/standards/documents/DSP0222_1.0.0.pdf
>> [2] 12.6.5.4.3 VLAN
>>     https://cdrdv2.intel.com/v1/dl/getContent/613875
> 
> Please don't post the same patches more than once a day. You posted the
> same patches 3 times within 15 minutes with no major difference :/

Got it, sorry for misusing the mailing list. 

> Why is "ncsi,vlan-mode" set via the device tree? Looks like something
> that can be configured at runtime. 

Actually this cannot be configured at runtime, the NCSI spec defines no
command or register to determine which mode is supported by the device.
If kernel want to enable VLAN on the NCSI device, either "Filtered tagged
+ Untagged" (current default) or "Any tagged + untagged" mode should be
enabled, but unfortunately both of these two modes are documented to be
optionally supported in the spec. And in real cases, there are devices
that only supports one of them, or neither of them. So I added the device
tree property to configure which mode to use.