Re: [PATCH 03/15] soc: mediatek: Support GCE thread loop

["CK Hu (胡俊光)" <ck.hu@mediatek.com>]

Hi, Hsiao-chien:

On Wed, 2023-08-23 at 23:13 +0800, Hsiao Chien Sung wrote:
> Add a new API to create GCE thread loop by
> appending a command at the end of CMDQ packet
> to jump to the head of it.
> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
> ---
>  drivers/soc/mediatek/mtk-cmdq-helper.c | 30
> ++++++++++++++++++++++++++
>  include/linux/soc/mediatek/mtk-cmdq.h  |  2 ++
>  2 files changed, 32 insertions(+)
> 
> diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c
> b/drivers/soc/mediatek/mtk-cmdq-helper.c
> index c1837a468267..7d503d491c0d 100644
> --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> @@ -430,6 +430,9 @@ int cmdq_pkt_flush_async(struct cmdq_pkt *pkt)
>  	int err;
>  	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
>  
> +	dma_sync_single_for_device(client->chan->mbox->dev, pkt-
> >pa_base,
> +				   pkt->cmd_buf_size, DMA_TO_DEVICE);
> +
>  	err = mbox_send_message(client->chan, pkt);
>  	if (err < 0)
>  		return err;
> @@ -440,4 +443,31 @@ int cmdq_pkt_flush_async(struct cmdq_pkt *pkt)
>  }
>  EXPORT_SYMBOL(cmdq_pkt_flush_async);
>  
> +int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt)
> +{
> +	struct cmdq_instruction inst = { {0} };
> +	int err;
> +	u8 shift_pa = 0;
> +
> +	shift_pa = cmdq_get_shift_pa(((struct cmdq_client *)pkt->cl)-
> >chan);
> +
> +	/* insert EOC and generate IRQ for command iteration */
> +	inst.op = CMDQ_CODE_EOC;
> +	inst.value = CMDQ_EOC_IRQ_EN;

It's not necessary to trigger IRQ, so drop this.

> +	err = cmdq_pkt_append_command(pkt, inst);
> +	if (err < 0)
> +		return err;
> +
> +	/* jump to head of the packet */
> +	inst.op = CMDQ_CODE_JUMP;
> +	inst.offset = CMDQ_JUMP_RELATIVE;
> +	inst.value = pkt->pa_base >> shift_pa;
> +	err = cmdq_pkt_append_command(pkt, inst);

This function has only dump function, so rename this function to
relative dump and pass pkt->pa_base by client driver.

Regards,
CK

> +
> +	pkt->loop = true;
> +
> +	return err;
> +}
> +EXPORT_SYMBOL(cmdq_pkt_finalize_loop);
> +
>  MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/soc/mediatek/mtk-cmdq.h
> b/include/linux/soc/mediatek/mtk-cmdq.h
> index 3eb95ef34c6c..4c30f891d924 100644
> --- a/include/linux/soc/mediatek/mtk-cmdq.h
> +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> @@ -273,6 +273,8 @@ int cmdq_pkt_jump(struct cmdq_pkt *pkt,
> dma_addr_t addr);
>   */
>  int cmdq_pkt_finalize(struct cmdq_pkt *pkt);
>  
> +int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt);
> +
>  /**
>   * cmdq_pkt_flush_async() - trigger CMDQ to asynchronously execute
> the CMDQ
>   *                          packet and call back at the end of done
> packet