Re: [PATCH v2 1/2] mailbox: pcc: Add support for platform notification handling

[lihuisong (C)]

在 2023/3/27 19:30, Sudeep Holla 写道:
> On Tue, Mar 14, 2023 at 07:11:34PM +0800, Huisong Li wrote:
> > Currently, PCC driver doesn't support the processing of platform
> > notification for type 4 PCC subspaces.
> >
> > According to ACPI specification, if platform sends a notification
> > to OSPM, it must clear the command complete bit and trigger platform
> > interrupt. OSPM needs to check whether the command complete bit is
> > cleared, clear platform interrupt, process command, and then set the
> > command complete and ring doorbell to the Platform.
> >
> > Let us stash the value of the pcc type and use the same while processing
> > the interrupt of the channel. We also need to set the command complete
> > bit and ring doorbell in the interrupt handler for the type 4 channel to
> > complete the communication flow after processing the notification from
> > the Platform.
> >
> > Signed-off-by: Huisong Li <lihuisong@xxxxxxxxxx>
> > ---
> >   drivers/mailbox/pcc.c | 50 +++++++++++++++++++++++++++++++++++--------
> >   1 file changed, 41 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
> > index 105d46c9801b..a0a87c480d8b 100644
> > --- a/drivers/mailbox/pcc.c
> > +++ b/drivers/mailbox/pcc.c
> > @@ -91,6 +91,7 @@ struct pcc_chan_reg {
> >    * @cmd_update: PCC register bundle for the command complete update register
> >    * @error: PCC register bundle for the error status register
> >    * @plat_irq: platform interrupt
> > + * @type: PCC subspace type
> >    */
> >   struct pcc_chan_info {
> >   	struct pcc_mbox_chan chan;
> > @@ -100,12 +101,15 @@ struct pcc_chan_info {
> >   	struct pcc_chan_reg cmd_update;
> >   	struct pcc_chan_reg error;
> >   	int plat_irq;
> > +	u8 type;
> >   };
> >   
> >   #define to_pcc_chan_info(c) container_of(c, struct pcc_chan_info, chan)
> >   static struct pcc_chan_info *chan_info;
> >   static int pcc_chan_count;
> >   
> > +static int pcc_send_data(struct mbox_chan *chan, void *data);
> > +
> >   /*
> >    * PCC can be used with perf critical drivers such as CPPC
> >    * So it makes sense to locally cache the virtual address and
> > @@ -221,6 +225,34 @@ static int pcc_map_interrupt(u32 interrupt, u32 flags)
> >   	return acpi_register_gsi(NULL, interrupt, trigger, polarity);
> >   }
> >   
> > +static bool pcc_mbox_cmd_complete_check(struct pcc_chan_info *pchan)
> > +{
> > +	u64 val;
> > +	int ret;
> > +
> > +	ret = pcc_chan_reg_read(&pchan->cmd_complete, &val);
> > +	if (ret)
> > +		return false;
> > +
> > +	if (!pchan->cmd_complete.gas)
> > +		return true;
> > +
> > +	/*
> > +	 * Judge if the channel respond the interrupt based on the value of
> > +	 * command complete.
> > +	 */
> > +	val &= pchan->cmd_complete.status_mask;
> [super nit] Would prefer an blank line here.
Yeah, it would be better if there is an blank line here.
Is it necessary to send v3 for this?