Re: [PATCH v5 1/6] iommu/arm-smmu-v3: Add CS_NONE quirk

From: Nicolin Chen <nicolinc@nvidia.com>
To: <will@kernel.org>, <robin.murphy@arm.com>
Cc: <joro@8bytes.org>, <jgg@nvidia.com>, <thierry.reding@gmail.com>,
	<vdumpa@nvidia.com>, <jonathanh@nvidia.com>,
	<linux-kernel@vger.kernel.org>, <iommu@lists.linux.dev>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-tegra@vger.kernel.org>
Subject: Re: [PATCH v5 1/6] iommu/arm-smmu-v3: Add CS_NONE quirk
Date: Fri, 19 Apr 2024 10:12:44 -0700	[thread overview]
Message-ID: <ZiKmDCAnAc0sRT7K@Asurada-Nvidia> (raw)
In-Reply-To: <10a39a51cae4de9ef47580f0c4439fb6c5373588.1712977210.git.nicolinc@nvidia.com>

On Fri, Apr 12, 2024 at 08:43:49PM -0700, Nicolin Chen wrote:
> The CMDQV extension in NVIDIA Tegra241 SoC only supports CS_NONE in the
> CS field of CMD_SYNC. Add a quirk flag to accommodate that.
> 
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++++++--
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  4 ++++
>  2 files changed, 12 insertions(+), 2 deletions(-)

> @@ -707,7 +712,8 @@ static int __arm_smmu_cmdq_poll_until_consumed(struct arm_smmu_device *smmu,
>  static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu,
>                                          struct arm_smmu_ll_queue *llq)
>  {
> -       if (smmu->options & ARM_SMMU_OPT_MSIPOLL)
> +       if (smmu->options & ARM_SMMU_OPT_MSIPOLL &&
> +           !(cmdq->q.quirks & CMDQ_QUIRK_SYNC_CS_NONE_ONLY))
>                 return __arm_smmu_cmdq_poll_until_msi(smmu, llq);

Realized that I should have moved the PATCH-4 to the top for the
cmdq pointer here. Otherwise it breaks git-bisect... Will fix in
the next version.

Nicolin