Re: [PATCH v8 10/20] soc: mediatek: mtk-cmdq: Extend cmdq_pkt_write API for SoCs without subsys ID

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 17/10/25 08:44, Jason-JH Lin ha scritto:
> This patch extends the cmdq_pkt_write API to support SoCs that do not
> have subsys ID mapping by introducing new register write APIs:
> - cmdq_pkt_write_pa() and cmdq_pkt_write_subsys() replace
>    cmdq_pkt_write()
> - cmdq_pkt_write_mask_pa() and cmdq_pkt_write_mask_subsys() replace
>    cmdq_pkt_write_mask()
> 
> To ensure consistent function pointer interfaces, both
> cmdq_pkt_write_pa() and cmdq_pkt_write_subsys() provide subsys and
> pa_base parameters. This unifies how register writes are invoked,
> regardless of whether subsys ID is supported by the device.
> 
> All GCEs support writing registers by PA (with mask) without subsys,
> but this requires extra GCE instructions to convert the PA into a GCE
> readable format, reducing performance compared to using subsys directly.
> Therefore, subsys is preferred for register writes when available.
> 
> API documentation and function pointer declarations in cmdq_client_reg
> have been updated. The original write APIs will be removed after all
> CMDQ users transition to the new interfaces.
> 
> Signed-off-by: Jason-JH Lin <jason-jh.lin@mediatek.com>
> ---
>   drivers/soc/mediatek/mtk-cmdq-helper.c | 54 +++++++++++++++++
>   include/linux/soc/mediatek/mtk-cmdq.h  | 83 ++++++++++++++++++++++++++
>   2 files changed, 137 insertions(+)
> 

> diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
> index 154d0511a0ad..f6dc43c036bd 100644
> --- a/include/linux/soc/mediatek/mtk-cmdq.h
> +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> @@ -57,6 +57,10 @@ struct cmdq_client_reg {
>   	phys_addr_t pa_base;
>   	u16 offset;
>   	u16 size;
> +	int (*reg_write)(struct cmdq_pkt *pkt, u8 subsys, u32 pa_base,
> +			 u16 offset, u32 value);

(*pkt_write)

> +	int (*reg_write_mask)(struct cmdq_pkt *pkt, u8 subsys, u32 pa_base,
> +			      u16 offset, u32 value, u32 mask);

(*pkt_write_mask)

those names make a lot more sense.

After applying the requested changes,

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

>   };