Re: [PATCH v16 6/9] irqchip: Add RISC-V advanced PLIC driver for direct-mode

From: Thomas Gleixner <tglx@linutronix.de>
To: niliqiang <ni_liqiang@126.com>, maz@kernel.org
Cc: ajones@ventanamicro.com, anup@brainfault.org,
	apatel@ventanamicro.com, atishp@atishpatra.org, bjorn@kernel.org,
	conor+dt@kernel.org, dai.hualiang@zte.com.cn,
	deng.weixian@zte.com.cn, devicetree@vger.kernel.org,
	frowand.list@gmail.com, guo.chang2@zte.com.cn,
	hu.yuye@zte.com.cn, krzysztof.kozlowski+dt@linaro.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org,
	liu.qingtao2@zte.com.cn, liu.wenhong35@zte.com.cn,
	ni.liqiang@zte.com.cn, ni_liqiang@126.com, palmer@dabbelt.com,
	paul.walmsley@sifive.com, robh+dt@kernel.org,
	saravanak@google.com, sunilvl@ventanamicro.com,
	wu.jiabao@zte.com.cn
Subject: Re: [PATCH v16 6/9] irqchip: Add RISC-V advanced PLIC driver for direct-mode
Date: Tue, 25 Nov 2025 17:42:09 +0100	[thread overview]
Message-ID: <87qztmgj32.ffs@tglx> (raw)
In-Reply-To: <20251125160731.4902-1-ni_liqiang@126.com>

On Wed, Nov 26 2025 at 00:07, niliqiang wrote:
> We've noticed that PCIe enumeration order tends to vary across system reboots (for example: first
> boot showed PC08->PC06->PC10->PC07->PC11->PC09, while second boot showed
> PC09->PC06->PC08->PC11->PC07->PC10), even though the ACPI firmware consistently reports the root
> bridge sequence as PC06->PC07->PC08->PC09->PC10->PC11.
>
> In our testing, we found that adjusting the registration priority of the aplic driver seems to help
> ensure the interrupt controller initializes before PCI enumeration, leading to more consistent
> device ordering.

You're repeating yourself over and over, but you're missing the point.

The ACPI table does not provide a sequence, it provides a collection and
it's nowhere written in stone that this collection has to be processed
in order.

If you want a sequence then put dependencies into the table and be done
with it, no?

Thanks,

        tglx