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Date:   Tue, 18 Apr 2023 08:50:05 +0900
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Subject: Re: [PATCH v4 10/11] PCI: rockchip: Don't advertise MSI-X in PCIe
 capabilities
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To:     Rick Wertenbroek <rick.wertenbroek@gmail.com>,
        alberto.dassatti@heig-vd.ch
Cc:     xxm@rock-chips.com, Shawn Lin <shawn.lin@rock-chips.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= <kw@linux.com>,
        Rob Herring <robh@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Heiko Stuebner <heiko@sntech.de>,
        Brian Norris <briannorris@chromium.org>,
        Johan Jonker <jbx6244@gmail.com>,
        Caleb Connolly <kc@postmarketos.org>,
        Corentin Labbe <clabbe@baylibre.com>,
        Judy Hsiao <judyhsiao@chromium.org>,
        Arnaud Ferraris <arnaud.ferraris@collabora.com>,
        Hugh Cole-Baker <sigmaris@gmail.com>,
        linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20230417092631.347976-1-rick.wertenbroek@gmail.com>
 <20230417092631.347976-11-rick.wertenbroek@gmail.com>
From:   Damien Le Moal <dlemoal@kernel.org>
Organization: Western Digital Research
In-Reply-To: <20230417092631.347976-11-rick.wertenbroek@gmail.com>
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On 4/17/23 18:26, Rick Wertenbroek wrote:
> The RK3399 PCIe endpoint controller cannot generate MSI-X IRQs.
> This is documented in the RK3399 technical reference manual (TRM)
> section 17.5.9 "Interrupt Support".
> 
> MSI-X capability should therefore not be advertised. Remove the
> MSI-X capability by editing the capability linked-list. The
> previous entry is the MSI capability, therefore get the next
> entry from the MSI-X capability entry and set it as next entry
> for the MSI capability. This in effect removes MSI-X from the list.
> 
> Linked list before : MSI cap -> MSI-X cap -> PCIe Device cap -> ...
> Linked list now : MSI cap -> PCIe Device cap -> ...
> 
> Signed-off-by: Rick Wertenbroek <rick.wertenbroek@gmail.com>
> Tested-by: Damien Le Moal <dlemoal@kernel.org>

Looks good, but I think you need to add also:

Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller")
Cc: stable@vger.kernel.org

Otherwise, feel free to add:

Reviewed-by: Damien Le Moal <dlemoal@kernel.org>