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Date:   Mon, 17 Apr 2023 17:39:10 +0100
Message-ID: <868reqlaz5.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Sebastian Reichel <sebastian.reichel@collabora.com>
Cc:     Heiko Stuebner <heiko@sntech.de>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peng Fan <peng.fan@nxp.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Peter Geis <pgwipeout@gmail.com>,
        XiaoDong Huang <derrick.huang@rock-chips.com>,
        Kever Yang <kever.yang@rock-chips.com>,
        linux-rockchip@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel@collabora.com
Subject: Re: [PATCH v2 2/2] arm64: dts: rockchip: rk3588: add MSI support
In-Reply-To: <20230417150038.51698-3-sebastian.reichel@collabora.com>
References: <20230417150038.51698-1-sebastian.reichel@collabora.com>
        <20230417150038.51698-3-sebastian.reichel@collabora.com>
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On Mon, 17 Apr 2023 16:00:38 +0100,
Sebastian Reichel <sebastian.reichel@collabora.com> wrote:
> 
> Add the two Interrupt Translation Service (ITS) IPs that are part of the
> GIC-600, which are required for message signalled interrupts (MSI). This
> is required for PCIe, which fully relies on MSI for interrupts.
> 
> Enabling the ITS nodes requires an operating system, that has a
> workaround for Rockchip errata #3588001 (GIC600 can not support
> shareable attribute).

$SUBJECT is inaccurate. This adds the descriptions of the ITSs, but
doesn't wire any MSI support at all (nobody even refers these
nodes, so the whole thing is pretty pointless).

	M.

-- 
Without deviation from the norm, progress is not possible.