Re: [PATCH v7 1/3] iommu/arm-smmu-v3: Factor out CMDQ batch force-sync conditions

[Jason Gunthorpe]

On Tue, Jul 14, 2026 at 10:42:00AM +0000, Ashish Mhetre wrote:
> From: Nicolin Chen <nicolinc@xxxxxxxxxx>
> 
> arm_smmu_cmdq_batch_add_cmd_p() carries two distinct reasons for
> flushing the current batch with a CMD_SYNC before appending the
> new command:
> 
>   - The batch's pre-assigned cmdq does not support the new command.
>   - The Arm erratum 2812531 workaround (ARM_SMMU_OPT_CMDQ_FORCE_SYNC)
>     forces a SYNC at one entry before the batch is full.
> 
> Lift those checks into a new arm_smmu_cmdq_batch_force_sync() helper
> so that adding another force-sync condition becomes a one-line
> addition. No functional change.
> 
> Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Ashish Mhetre <amhetre@xxxxxxxxxx>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 23 +++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason