Message-ID: <98dfa822-218b-6ad9-4fd0-56a8e5d2bd02@arm.com>
Date:   Mon, 29 Nov 2021 13:25:27 +0000
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Subject: Re: [patch 33/37] iommu/arm-smmu-v3: Use msi_get_virq()
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To:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Will Deacon <will@kernel.org>
Cc:     Nishanth Menon <nm@ti.com>, Mark Rutland <mark.rutland@arm.com>,
        Stuart Yoder <stuyoder@gmail.com>, linux-pci@vger.kernel.org,
        Ashok Raj <ashok.raj@intel.com>, Marc Zygnier <maz@kernel.org>,
        x86@kernel.org, Sinan Kaya <okaya@kernel.org>,
        iommu@lists.linux-foundation.org,
        Bjorn Helgaas <helgaas@kernel.org>,
        Megha Dey <megha.dey@intel.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Santosh Shilimkar <ssantosh@kernel.org>,
        linux-arm-kernel@lists.infradead.org,
        Tero Kristo <kristo@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Vinod Koul <vkoul@kernel.org>, dmaengine@vger.kernel.org
References: <20211126224100.303046749@linutronix.de>
 <20211126230525.885757679@linutronix.de>
From:   Robin Murphy <robin.murphy@arm.com>
In-Reply-To: <20211126230525.885757679@linutronix.de>
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On 2021-11-27 01:22, Thomas Gleixner wrote:
> Let the core code fiddle with the MSI descriptor retrieval.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> ---
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c |   19 +++----------------
>   1 file changed, 3 insertions(+), 16 deletions(-)
> 
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -3154,7 +3154,6 @@ static void arm_smmu_write_msi_msg(struc
>   
>   static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
>   {
> -	struct msi_desc *desc;
>   	int ret, nvec = ARM_SMMU_MAX_MSIS;
>   	struct device *dev = smmu->dev;
>   
> @@ -3182,21 +3181,9 @@ static void arm_smmu_setup_msis(struct a
>   		return;
>   	}
>   
> -	for_each_msi_entry(desc, dev) {
> -		switch (desc->msi_index) {
> -		case EVTQ_MSI_INDEX:
> -			smmu->evtq.q.irq = desc->irq;
> -			break;
> -		case GERROR_MSI_INDEX:
> -			smmu->gerr_irq = desc->irq;
> -			break;
> -		case PRIQ_MSI_INDEX:
> -			smmu->priq.q.irq = desc->irq;
> -			break;
> -		default:	/* Unknown */
> -			continue;
> -		}
> -	}
> +	smmu->evtq.q.irq = msi_get_virq(dev, EVTQ_MSI_INDEX);
> +	smmu->gerr_irq = msi_get_virq(dev, GERROR_MSI_INDEX);
> +	smmu->priq.q.irq = msi_get_virq(dev, PRIQ_MSI_INDEX);

FWIW I've just quickly booted the msi-v1-part-2 branch on a platform 
with MSIs but no PRI such that this now sets priq.q.irq to an error 
value, and as I predicted it's still happy.

Tested-by: Robin Murphy <robin.murphy@arm.com>

Cheers,
Robin.

>   	/* Add callback to free MSIs on teardown */
>   	devm_add_action(dev, arm_smmu_free_msis, dev);
> 
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