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From: Andrew Jeffery <>
Subject: [PATCH v3 0/2] serial: 8250: Mitigate Tx stall risk for Aspeed VUARTs
Date: Thu, 20 May 2021 11:43:32 +0930	[thread overview]
Message-ID: <> (raw)


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.

v3 addresses comments from Jiri on v2. v2 can be found here:

The documentation patch that fell out of the discussion of patch 2 of v2 can be
found here:

Please review!


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         | 12 ++++++++
 3 files changed, 30 insertions(+), 15 deletions(-)


linux-arm-kernel mailing list

             reply	other threads:[~2021-05-20  2:17 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-20  2:13 Andrew Jeffery [this message]
2021-05-20  2:13 ` [PATCH v3 1/2] serial: 8250: Add UART_BUG_TXRACE workaround for Aspeed VUART Andrew Jeffery
2021-05-20  5:24   ` Jiri Slaby
2021-05-20  5:42     ` ChiaWei Wang
2021-05-20  2:13 ` [PATCH v3 2/2] serial: 8250: Use BIT(x) for UART_{CAP,BUG}_* Andrew Jeffery
2021-05-20  5:25   ` Jiri Slaby

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