[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20220220095431.GA5251@amd>
Date: Sun, 20 Feb 2022 10:54:33 +0100
From: Pavel Machek <pavel@....cz>
To: Sasha Levin <sashal@...nel.org>
Cc: linux-kernel@...r.kernel.org, stable@...r.kernel.org,
Guo Ren <guoren@...ux.alibaba.com>,
Anup Patel <anup@...infault.org>,
Marc Zyngier <maz@...nel.org>,
Palmer Dabbelt <palmer@...belt.com>,
Samuel Holland <samuel@...lland.org>,
Thomas Gleixner <tglx@...utronix.de>, paul.walmsley@...ive.com,
aou@...s.berkeley.edu, linux-riscv@...ts.infradead.org
Subject: Re: [PATCH AUTOSEL 4.19 03/11] irqchip/sifive-plic: Add missing
thead,c900-plic match string
Hi!
> [ Upstream commit 1d4df649cbb4b26d19bea38ecff4b65b10a1bbca ]
>
> The thead,c900-plic has been used in opensbi to distinguish
> PLIC [1]. Although PLICs have the same behaviors in Linux,
> they are different hardware with some custom initializing in
> firmware(opensbi).
>
> Qute opensbi patch commit-msg by Samuel:
>
> The T-HEAD PLIC implementation requires setting a delegation bit
> to allow access from S-mode. Now that the T-HEAD PLIC has its own
> compatible string, set this bit automatically from the PLIC driver,
> instead of reaching into the PLIC's MMIO space from another driver.
>
> [1]: https://github.com/riscv-software-src/opensbi/commit/78c2b19218bd62653b9fb31623a42ced45f38ea6
>
The "thead,c900-plic" string is added into single place in the
kernel. This means that a) it will probably not do anything useful in
-stable kernels and b) it is certainly missing documentation etc.
In mainline, string is documented in
Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml
Best regards,
Pavel
--
http://www.livejournal.com/~pavelmachek
Download attachment "signature.asc" of type "application/pgp-signature" (182 bytes)
Powered by blists - more mailing lists