Hi, Jason:
On Tue, 2023-09-19 at 03:21 +0800, Jason-JH.Lin wrote:
> Add cmdq_pkt_finalize_loop to CMDQ driver.
>
> cmdq_pkt_finalize_loop appends end of command(EOC) instruction and
> jump to start of command buffer instruction to make the command
> buffer loopable.
>
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> ---
> drivers/soc/mediatek/mtk-cmdq-helper.c | 23 +++++++++++++++++++++++
> include/linux/soc/mediatek/mtk-cmdq.h | 8 ++++++++
> 2 files changed, 31 insertions(+)
>
> diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c
> b/drivers/soc/mediatek/mtk-cmdq-helper.c
> index 4be2a18a4a02..bbb127620bb3 100644
> --- a/drivers/soc/mediatek/mtk-cmdq-helper.c
> +++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
> @@ -475,6 +475,29 @@ int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
> }
> EXPORT_SYMBOL(cmdq_pkt_finalize);
>
> +int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt)
> +{
> + struct cmdq_instruction inst = { {0} };
> + int err;
> +
> + /* insert EOC and generate IRQ for each command iteration */
> + inst.op = CMDQ_CODE_EOC;
> + inst.value = CMDQ_EOC_IRQ_EN;
> + err = cmdq_pkt_append_command(pkt, inst);
> + if (err < 0)
> + return err;
> +
> + /* JUMP to start of pkt */
> + err = cmdq_pkt_jump(pkt, pkt->pa_base);
> + if (err < 0)
> + return err;
Could you explain the case that a loop thread would trigger an
interrupt? In DRM crc function, the loop thread need not to trigger
interrupt, so I'm curious about this.
Regards,
CK
> +
> + pkt->loop = true;
> +
> + return err;
> +}
> +EXPORT_SYMBOL(cmdq_pkt_finalize_loop);
> +
> int cmdq_pkt_flush_async(struct cmdq_pkt *pkt)
> {
> int err;
> diff --git a/include/linux/soc/mediatek/mtk-cmdq.h
> b/include/linux/soc/mediatek/mtk-cmdq.h
> index 837ad8656adc..38a8e47da338 100644
> --- a/include/linux/soc/mediatek/mtk-cmdq.h
> +++ b/include/linux/soc/mediatek/mtk-cmdq.h
> @@ -323,6 +323,14 @@ int cmdq_pkt_jump(struct cmdq_pkt *pkt,
> dma_addr_t addr);
> */
> int cmdq_pkt_finalize(struct cmdq_pkt *pkt);
>
> +/**
> + * cmdq_pkt_finalize_loop() - Append EOC and jump to start command.
> + * @pkt: the CMDQ packet
> + *
> + * Return: 0 for success; else the error code is returned
> + */
> +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
