[U-Boot] [PATCH v2 0/2] [for 2018.03] RPi: Drain RX queue on setbrg

Alexander Graf
2018-03-07T21:08:23Z

We had a few reports coming in from people that had their autoboot chain
aborted after pinmuxing support was added for the RPi.

The culprit is easy: The UARTs may have been enabled before, but muxed
to an incorrect pin. That pin may have pulled the RX line down which again
lead to lots of zero bytes gathered in the RX buffer.

The easy fix for that is to drain the RX queue every time we set the baud
rate.

This patch set is the minimally intrusive fix for the RPi. We may want to
do that generically for all serial devices later.

v1 -> v2:

- fix pl011 draining

Alexander Graf (2):
serial_bcm283x_mu: Flush RX queue after setting baud rate
bcm283x_pl011: Flush RX queue after setting baud rate

drivers/serial/serial_bcm283x_mu.c | 8 +++++++-
drivers/serial/serial_bcm283x_pl011.c | 25 ++++++++++++++++++++++++-
drivers/serial/serial_pl01x.c | 10 +++++-----
drivers/serial/serial_pl01x_internal.h | 7 ++++++-
4 files changed, 42 insertions(+), 8 deletions(-)

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2.12.3