From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201])
	(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
	(No client certificate requested)
	by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4CFBC7A
	for <loongarch@lists.linux.dev>; Sun, 17 Jul 2022 14:49:14 +0000 (UTC)
Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEE77C3411E;
	Sun, 17 Jul 2022 14:49:13 +0000 (UTC)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;
	s=k20201202; t=1658069354;
	bh=UMJ1Z2fe6K1nWixxQBvPJvOJwCRiE+j98okIMbZFGsU=;
	h=Date:From:To:Cc:Subject:In-Reply-To:References:From;
	b=sOB2xaQUdojCT+YZURDw6vzWPH2e8/Gis6UxvACTFYp6MVvtWxmWUlFFYUdJwNnPn
	 wL0MheXEwkgpfKXjFeNVOVxTT7PuEFq1dqloTO3p4n6ma6BhAodh4VTKeDHJSfdE6B
	 AR2vOf/XLjpDmpyrXeMbp1YIXNRIpaZYf3vSTLOlTxZWkstVaoo/9AaNLKJ7x3xitG
	 htwvHokSVFafEE9M0j6992S7/hMg9ACdZoTjvbeMhY8ZalLDeYf23CpdWAK76JbUbt
	 iwSfAzI+mB9LH1R0UZeProrr9RT16TyjHldd2fyGqwolBr688erin97+pDCvL+D5F/
	 c0v+NmMcnV70w==
Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org)
	by disco-boy.misterjones.org with esmtpsa  (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.95)
	(envelope-from <maz@kernel.org>)
	id 1oD5a3-0081Km-Qq;
	Sun, 17 Jul 2022 15:49:11 +0100
Date: Sun, 17 Jul 2022 15:49:11 +0100
Message-ID: <87wncbzteg.wl-maz@kernel.org>
From: Marc Zyngier <maz@kernel.org>
To: Jianmin Lv <lvjianmin@loongson.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	linux-kernel@vger.kernel.org,
	loongarch@lists.linux.dev,
	Hanjun Guo <guohanjun@huawei.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Jiaxun Yang <jiaxun.yang@flygoat.com>,
	Huacai Chen <chenhuacai@loongson.cn>
Subject: Re: [PATCH V15 00/15] irqchip: Add LoongArch-related irqchip drivers
In-Reply-To: <20994a99-b5b1-442d-d23d-2a11ecef24a0@loongson.cn>
References: <1657868751-30444-1-git-send-email-lvjianmin@loongson.cn>
	<87less52bx.wl-maz@kernel.org>
	<6e9def1e-31fe-787d-1b2b-a328424352f0@loongson.cn>
	<87ilnw3vlg.wl-maz@kernel.org>
	<20994a99-b5b1-442d-d23d-2a11ecef24a0@loongson.cn>
User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue)
 FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1
 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO)
Precedence: bulk
X-Mailing-List: loongarch@lists.linux.dev
List-Id: <loongarch.lists.linux.dev>
List-Subscribe: <mailto:loongarch+subscribe@lists.linux.dev>
List-Unsubscribe: <mailto:loongarch+unsubscribe@lists.linux.dev>
MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue")
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
X-SA-Exim-Connect-IP: 185.219.108.64
X-SA-Exim-Rcpt-To: lvjianmin@loongson.cn, tglx@linutronix.de, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, guohanjun@huawei.com, lorenzo.pieralisi@arm.com, jiaxun.yang@flygoat.com, chenhuacai@loongson.cn
X-SA-Exim-Mail-From: maz@kernel.org
X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false

On Sun, 17 Jul 2022 12:29:05 +0100,
Jianmin Lv <lvjianmin@loongson.cn> wrote:
>=20
>=20
>=20
> On 2022/7/17 =E4=B8=8B=E5=8D=886:02, Marc Zyngier wrote:
> > But the other issue is that you seem to call this function from two
> > different locations. This cannot be right, as there should be only one
> > probe order, and not multiple.
> >=20
>=20
> As we described two IRQ models(Legacy and Extended) in this cover
> letter, the parent domain of MSI domain can be htvec domain(Legacy) or
> eiointc domain(Extended). In MADT, only one APIC(HTPIC for htvec or
> EIOPIC for eiointc) is allowed to pass into kernel, and then in the
> irqchip driver, only one kind APIC of them can be parsed from MADT, so
> we have to support two probe order for them.

Do you really have the two variants in the wild? Or is this just
because this is a possibility?

	M.

--=20
Without deviation from the norm, progress is not possible.