On Wed, Jun 12, 2024 at 02:45:31PM -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.
>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> ---
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 +++++++-
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 +++
> 2 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index c864c634cd23..ba0e24d5ffbf 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -345,6 +345,11 @@ static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
> FIELD_PREP(CMDQ_SYNC_0_MSH, ARM_SMMU_SH_ISH) |
> FIELD_PREP(CMDQ_SYNC_0_MSIATTR, ARM_SMMU_MEMATTR_OIWB);
>
> + if (q->quirks & CMDQ_QUIRK_SYNC_CS_NONE_ONLY) {
> + cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_NONE);
> + return;
> + }
> +
> if (!(smmu->options & ARM_SMMU_OPT_MSIPOLL)) {
> cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_SEV);
> return;
> @@ -690,7 +695,8 @@ static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu,
> struct arm_smmu_cmdq *cmdq,
> 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, cmdq, llq);
>
> return __arm_smmu_cmdq_poll_until_consumed(smmu, cmdq, llq);
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> index 180c0b1e0658..01227c0de290 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
> @@ -543,6 +543,9 @@ struct arm_smmu_queue {
>
> u32 __iomem *prod_reg;
> u32 __iomem *cons_reg;
> +
> +#define CMDQ_QUIRK_SYNC_CS_NONE_ONLY BIT(0) /* CMD_SYNC CS field supports CS_NONE only */
> + u32 quirks;
Please can you use the existing smmu->options field instead of adding
another place to track quirks? Or do you need this only for some of the
queues for a given SMMU device?
Thanks,
Will
