mailbox: rp1: Don't poll for TX completion#7501
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The RP1 mailbox + firmware interface is currently synchronous, with only one outstanding message at a time and the same buffer used for the reply. It is therefore of no use to know when the transmit has completed, only that the reply is ready. This is TXDONE_BY_ACK mode, which is automatically selected if neither txdone_irq nor txdone_poll are provided. This change increases performance and reduces hrtimer usage significantly, but it requires the mailbox client to call mbox_client_txdone after each transmission. Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Now that TX polling has been disabled and the mailbox is running in TXDONE_BY_ACK mode, call mbox_client_txdone after each transmission to tell the mailbox framework that the transmission has completed. Signed-off-by: Phil Elwell <phil@raspberrypi.com>
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This PR replaces #7448. |
popcornmix
approved these changes
Jul 15, 2026
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The RP1 mailbox + firmware interface is currently synchronous, with
only one outstanding message at a time and the same buffer used for the
reply. It is therefore of no use to know when the transmit has
completed, only that the reply is ready. This is TXDONE_BY_ACK mode,
which is automatically selected if neither txdone_irq nor txdone_poll
are provided.
This change increases performance and reduces hrtimer usage
significantly, but it requires the mailbox client to call
mbox_client_txdone after each transmission.