Re: [RFC PATCH v2 30/31] kvx: Add power controller driver

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: "Yann Sionneau" <ysionneau@kalray.eu>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Marc Zyngier" <maz@kernel.org>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
	"Will Deacon" <will@kernel.org>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Boqun Feng" <boqun.feng@gmail.com>,
	"Mark Rutland" <mark.rutland@arm.com>,
	"Eric Biederman" <ebiederm@xmission.com>,
	"Kees Cook" <keescook@chromium.org>,
	"Oleg Nesterov" <oleg@redhat.com>,
	"Ingo Molnar" <mingo@redhat.com>,
	"Waiman Long" <longman@redhat.com>,
	"Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Nick Piggin" <npiggin@gmail.com>,
	"Paul Moore" <paul@paul-moore.com>,
	"Eric Paris" <eparis@redhat.com>,
	"Christian Brauner" <brauner@kernel.org>,
	"Paul Walmsley" <paul.walmsley@sifive.com>,
	"Palmer Dabbelt" <palmer@dabbelt.com>,
	"Albert Ou" <aou@eecs.berkeley.edu>,
	"Jules Maselbas" <jmaselbas@kalray.eu>,
	"Guillaume Thouvenin" <gthouvenin@kalray.eu>,
	"Clement Leger" <clement@clement-leger.fr>,
	"Vincent Chardon" <vincent.chardon@elsys-design.com>,
	"Marc Poulhiès" <dkm@kataplop.net>,
	"Julian Vetter" <jvetter@kalray.eu>,
	"Samuel Jones" <sjones@kalray.eu>,
	"Ashley Lesdalons" <alesdalons@kalray.eu>,
	"Thomas Costis" <tcostis@kalray.eu>,
	"Marius Gligor" <mgligor@kalray.eu>,
	"Jonathan Borne" <jborne@kalray.eu>,
	"Julien Villette" <jvillette@kalray.eu>,
	"Luc Michel" <lmichel@kalray.eu>,
	"Louis Morhet" <lmorhet@kalray.eu>,
	"Julien Hascoet" <jhascoet@kalray.eu>,
	"Jean-Christophe Pince" <jcpince@gmail.com>,
	"Guillaume Missonnier" <gmissonnier@kalray.eu>,
	"Alex Michon" <amichon@kalray.eu>,
	"Huacai Chen" <chenhuacai@kernel.org>,
	"WANG Xuerui" <git@xen0n.name>,
	"Shaokun Zhang" <zhangshaokun@hisilicon.com>,
	"John Garry" <john.garry@huawei.com>,
	"Guangbin Huang" <huangguangbin2@huawei.com>,
	"Bharat Bhushan" <bbhushan2@marvell.com>,
	"Bibo Mao" <maobibo@loongson.cn>,
	"Atish Patra" <atishp@atishpatra.org>,
	"Jason A. Donenfeld" <Jason@zx2c4.com>,
	"Qi Liu" <liuqi115@huawei.com>,
	"Jiaxun Yang" <jiaxun.yang@flygoat.com>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Mark Brown" <broonie@kernel.org>,
	"Janosch Frank" <frankja@linux.ibm.com>,
	"Alexey Dobriyan" <adobriyan@gmail.com>
Cc: Benjamin Mugnier <mugnier.benjamin@gmail.com>,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org, linux-mm@kvack.org,
	linux-arch@vger.kernel.org, linux-audit@redhat.com,
	linux-riscv@lists.infradead.org, bpf@vger.kernel.org
Subject: Re: [RFC PATCH v2 30/31] kvx: Add power controller driver
Date: Sun, 22 Jan 2023 12:54:11 +0100	[thread overview]
Message-ID: <f69adaf2-6582-c134-5671-4d6fd100fcf1@linaro.org> (raw)
In-Reply-To: <20230120141002.2442-31-ysionneau@kalray.eu>

On 20/01/2023 15:10, Yann Sionneau wrote:
> From: Jules Maselbas <jmaselbas@kalray.eu>
> 
> The Power Controller (pwr-ctrl) control cores reset and wake-up
> procedure.

> +
> +static struct device_node * __init get_pwr_ctrl_node(void)
> +{
> +	const phandle *ph;
> +	struct device_node *cpu;
> +	struct device_node *node;
> +
> +	cpu = of_get_cpu_node(raw_smp_processor_id(), NULL);
> +	if (!cpu) {
> +		pr_err("Failed to get CPU node\n");
> +		return NULL;
> +	}
> +
> +	ph = of_get_property(cpu, "power-controller", NULL);
> +	if (!ph) {
> +		pr_err("Failed to get power-controller phandle\n");
> +		return NULL;
> +	}
> +
> +	node = of_find_node_by_phandle(be32_to_cpup(ph));
> +	if (!node) {
> +		pr_err("Failed to get power-controller node\n");
> +		return NULL;
> +	}
> +
> +	return node;
> +}
> +
> +int __init kvx_pwr_ctrl_probe(void)
> +{
> +	struct device_node *ctrl;
> +
> +	ctrl = get_pwr_ctrl_node();
> +	if (!ctrl) {
> +		pr_err("Failed to get power controller node\n");
> +		return -EINVAL;
> +	}
> +
> +	if (!of_device_is_compatible(ctrl, "kalray,kvx-pwr-ctrl")) {
> +		pr_err("Failed to get power controller node\n");

No. Drivers go to drivers, not to arch directory. This should be a
proper driver instead of some fake stub doing its own driver matching.
You need to rework this.

Best regards,
Krzysztof