答复: [PATCH 1/1] firmware: arm_scmi/mailbox: ignore notification for tx done using irq

From: Zhu, Joe
Date: Sun May 10 2020 - 20:58:12 EST


Hi Sudeep,
Yes, mailbox client does not need to know how controller implemented. I will check with mailbox driver. Thanks!


Regards,
Joe


-----邮件原件-----
发件人: Sudeep Holla [mailto:sudeep.holla@xxxxxxx]
发送时间: 2020年5月9日 23:20
收件人: joe_zhuchg@xxxxxxx
抄送: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Sudeep Holla; Zhu, Joe
主题: Re: [PATCH 1/1] firmware: arm_scmi/mailbox: ignore notification for tx done using irq

On Sat, May 09, 2020 at 04:54:57PM +0800, joe_zhuchg@xxxxxxx wrote:
> From: Joe Zhu <Chunguang.Zhu@xxxxxxxxxxxxxxx>
>
> If mailbox uses IRQ method, it already notified framework with
> mbox_chan_txdone() in ISR.
>
> Signed-off-by: Joe Zhu <Chunguang.Zhu@xxxxxxxxxxxxxxx>
> ---
> drivers/firmware/arm_scmi/mailbox.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
> index 73077bbc4ad9..303a5dc42429 100644
> --- a/drivers/firmware/arm_scmi/mailbox.c
> +++ b/drivers/firmware/arm_scmi/mailbox.c
> @@ -9,6 +9,7 @@
> #include <linux/err.h>
> #include <linux/device.h>
> #include <linux/mailbox_client.h>
> +#include <linux/mailbox_controller.h>

This is an indication that something is wrong. The mailbox controller
and client interfaces are very clear. You need to use mailbox controller
interface when implementing a mailbox controller and use only client
interface when implementing a mailbox client.

> #include <linux/of.h>
> #include <linux/of_address.h>
> #include <linux/slab.h>
> @@ -147,7 +148,8 @@ static void mailbox_mark_txdone(struct scmi_chan_info *cinfo, int ret)
> * Unfortunately, we have to kick the mailbox framework after we have
> * received our message.
> */
> - mbox_client_txdone(smbox->chan, ret);
> + if (!smbox->chan->mbox->txdone_irq)
> + mbox_client_txdone(smbox->chan, ret);

If this patch is to avoid getting "Client can't run the TX ticker" error
messages, then you make need to fix that with something like below:

Regards,
Sudeep

-->8
diff --git i/drivers/mailbox/mailbox.c w/drivers/mailbox/mailbox.c
index 0b821a5b2db8..5a78a0adcce4 100644
--- i/drivers/mailbox/mailbox.c
+++ w/drivers/mailbox/mailbox.c
@@ -189,7 +189,9 @@ EXPORT_SYMBOL_GPL(mbox_chan_txdone);
void mbox_client_txdone(struct mbox_chan *chan, int r)
{
if (unlikely(!(chan->txdone_method & TXDONE_BY_ACK))) {
- dev_err(chan->mbox->dev, "Client can't run the TX ticker\n");
+ if (unlikely(!(chan->txdone_method & TXDONE_BY_IRQ)))
+ dev_err(chan->mbox->dev,
+ "Client can't run the TX ticker\n");
return;
}