Date:   Thu, 16 Dec 2021 15:06:18 +0000
Message-ID: <87pmpwwpw5.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Huacai Chen <chenhuacai@loongson.cn>
Cc:     Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
        Xuefeng Li <lixuefeng@loongson.cn>,
        Huacai Chen <chenhuacai@gmail.com>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>
Subject: Re: [PATCH V8 02/10] irqchip/loongson-pch-pic: Add ACPI init support
In-Reply-To: <20211216125356.632067-2-chenhuacai@loongson.cn>
References: <20211216125157.631992-1-chenhuacai@loongson.cn>
        <20211216125356.632067-1-chenhuacai@loongson.cn>
        <20211216125356.632067-2-chenhuacai@loongson.cn>
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On Thu, 16 Dec 2021 12:53:48 +0000,
Huacai Chen <chenhuacai@loongson.cn> wrote:
> 
> We are preparing to add new Loongson (based on LoongArch, not compatible
> with old MIPS-based Loongson) support. LoongArch use ACPI other than DT
> as its boot protocol, so add ACPI init support.
> 
> PCH-PIC/PCH-MSI stands for "Interrupt Controller" that described in
> Section 5 of "Loongson 7A1000 Bridge User Manual". For more information
> please refer Documentation/loongarch/irq-chip-model.rst.
> 
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
>  drivers/irqchip/irq-loongson-pch-pic.c | 108 ++++++++++++++++++-------
>  1 file changed, 81 insertions(+), 27 deletions(-)

[...]

>
> +#ifdef CONFIG_ACPI
> +
> +struct irq_domain *pch_pic_acpi_init(struct irq_domain *parent,
> +					struct acpi_madt_bio_pic *acpi_pchpic)

Who is calling this? This works the opposite way from what the arm64
irqchips are doing. Why? I have the ugly feeling that this is called
from the arch code, bypassing the existing infrastructure...

	M.

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