On Fri, Jun 18, 2021 at 03:05:03PM -0700, Bhaumik Bhatt wrote:
> From: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
>
> Event ring priorities are currently set to 1 and are unused.
> Default processing priority for event rings is set to regular
> tasklet. Controllers can choose to use high priority tasklet
> scheduling for certain event rings critical for processing such
> as ones transporting control information if they wish to avoid
> system scheduling delays for those packets. In order to support
> these use cases, allow controllers to set event ring priority to
> high.
>
> Signed-off-by: Hemant Kumar <hemantk@xxxxxxxxxxxxxx>
> Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Thanks,
Mani
> ---
> drivers/bus/mhi/core/init.c | 3 +--
> drivers/bus/mhi/core/main.c | 9 +++++++--
> include/linux/mhi.h | 2 +-
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index c81b377..4446760 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -673,8 +673,7 @@ static int parse_ev_cfg(struct mhi_controller *mhi_cntrl,
> &mhi_cntrl->mhi_chan[mhi_event->chan];
> }
>
> - /* Priority is fixed to 1 for now */
> - mhi_event->priority = 1;
> + mhi_event->priority = event_cfg->priority;
>
> mhi_event->db_cfg.brstmode = event_cfg->mode;
> if (MHI_INVALID_BRSTMODE(mhi_event->db_cfg.brstmode))
> diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
> index 8ac73f9..3775c77 100644
> --- a/drivers/bus/mhi/core/main.c
> +++ b/drivers/bus/mhi/core/main.c
> @@ -454,10 +454,15 @@ irqreturn_t mhi_irq_handler(int irq_number, void *dev)
>
> if (mhi_dev)
> mhi_notify(mhi_dev, MHI_CB_PENDING_DATA);
> - } else {
> - tasklet_schedule(&mhi_event->task);
> +
> + return IRQ_HANDLED;
> }
>
> + if (!mhi_event->priority)
> + tasklet_hi_schedule(&mhi_event->task);
> + else
> + tasklet_schedule(&mhi_event->task);
> +
> return IRQ_HANDLED;
> }
>
> diff --git a/include/linux/mhi.h b/include/linux/mhi.h
> index 86cea52..bf23c21 100644
> --- a/include/linux/mhi.h
> +++ b/include/linux/mhi.h
> @@ -250,7 +250,7 @@ struct mhi_channel_config {
> * @irq_moderation_ms: Delay irq for additional events to be aggregated
> * @irq: IRQ associated with this ring
> * @channel: Dedicated channel number. U32_MAX indicates a non-dedicated ring
> - * @priority: Priority of this ring. Use 1 for now
> + * @priority: Processing priority of this ring. 0 is high and 1 is regular
> * @mode: Doorbell mode
> * @data_type: Type of data this ring will process
> * @hardware_event: This ring is associated with hardware channels
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
