Re: [PATCH v4 1/2] iommu/arm-smmu-v3: Add a cmdq_entries module parameter

[Nicolin Chen]

On Wed, Sep 02, 2026 at 01:17:23PM +0100, Kiryl Shutsemau (Meta) wrote:
> +/**
> + * arm_smmu_queue_max_n_shift() - pick the log2 depth of a queue
> + * @hw_shift: log2 depth the hardware allows, capped for natural alignment
> + * @ent_sz_shift: log2 of the queue entry size in bytes
> + * @want: number of entries asked for, or zero to use @hw_shift
> + *
> + * @want is rounded down to a power of two. It never sizes a queue below one
> + * page, because coherent DMA is page granular: a shallower queue occupies the
> + * same memory as one that fills the page, and arm_smmu_init_one_queue() stops
> + * shrinking at a page too.

Well, since we want the cmdq depth, why not name the parameter
"max_cmdq_depth"? Then, no rounding and more straightforward.

Nicolin