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Subject[PATCH v2 0/2] serial: 8250: Mitigate Tx stall risk for Aspeed VUARTs
Date
Hello,

Briefly, the series works around a hardware race condition in the Tx path for
Aspeed virtual UARTs. A write burst to THR on the APB interface may provoke a
transfer stall where LSR[DR] on the LPC interface remains clear despite the
presence of data in the Rx FIFO.

For the work-around patch, v2 addresses the request for a comment about the use
of serial_in():

https://lore.kernel.org/lkml/d7918dcf-b938-498c-a012-3d93a748431b@www.fastmail.com/T/#md75702fbc3704bd4b375f1251a1415bcddea26a3

The second patch addresses the request for use of BIT() instead of an explicit
shift by converting all of the UART_{CAP,BUG}_* macros.

Please review!

Andrew

Andrew Jeffery (2):
serial: 8250: Add UART_BUG_TXRACE workaround for Aspeed VUART
serial: 8250: Use BIT(x) for UART_{CAP,BUG}_*

drivers/tty/serial/8250/8250.h | 32 +++++++++++----------
drivers/tty/serial/8250/8250_aspeed_vuart.c | 1 +
drivers/tty/serial/8250/8250_port.c | 10 +++++++
3 files changed, 28 insertions(+), 15 deletions(-)

--
2.30.2

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