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Date: Mon, 15 Apr 2024 18:15:23 -0500
From: Bjorn Helgaas <helgaas@kernel.org>
To: Sunil V L <sunilvl@ventanamicro.com>
Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
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	=?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
Subject: Re: [RFC PATCH v4 03/20] PCI: Make pci_create_root_bus() declare its
 reliance on MSI domains
Message-ID: <20240415231523.GA139682@bhelgaas>
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In-Reply-To: <20240415170113.662318-4-sunilvl@ventanamicro.com>

On Mon, Apr 15, 2024 at 10:30:56PM +0530, Sunil V L wrote:
> Similar to commit 9ec37efb8783 ("PCI/MSI: Make
> pci_host_common_probe() declare its reliance on MSI domains"), declare
> this dependency for PCI probe in ACPI based flow.
> 
> This is required especially for RISC-V platforms where MSI controller
> can be absent. However, setting this for all architectures seem to cause
> issues on non RISC-V architectures [1]. Hence, enabled this only for
> RISC-V.
> 
> [1] - https://lore.kernel.org/oe-lkp/202403041047.791cb18e-oliver.sang@intel.com
> 
> Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> ---
>  drivers/pci/probe.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 1325fbae2f28..e09915bee2ee 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -3048,6 +3048,9 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
>  	bridge->sysdata = sysdata;
>  	bridge->busnr = bus;
>  	bridge->ops = ops;
> +#ifdef CONFIG_RISCV
> +	bridge->msi_domain = true;
> +#endif

Ugh.  I looked at [1], but that's not a very good justification for
this #ifdef.  The fault mentioned in [1] would need to be fixed, but
not this way.

>  	error = pci_register_host_bridge(bridge);
>  	if (error < 0)
> -- 
> 2.40.1
>