Hi Greg,
On 26/01/2022 14:21, Greg Kroah-Hartman wrote:
On Wed, Jan 26, 2022 at 02:11:24PM +0000, Phil Elwell wrote:
The mini-UART on BCM283x is doubly crippled - it has 8-byte FIFOs and
the THRE bit indicates that the TX FIFO is not-full rather than empty.
The optimisation to enable the use of the FIFO assumes that it is safe
to write fifosize bytes whenever THRE is set, but the BCM283x quirk
(indicated by the presence of UART_CAP_MINI) makes it necessary to
check the FIFO state after each byte.
See: https://github.com/raspberrypi/linux/issues/4849
Fixes: 5021d709b31b ("tty: serial: Use fifo in 8250 console driver")
I have just reverted this commit, it's broken for many platforms now,
not just yours.
So there shouldn't be a need for this change now, right?
This patch is sufficient on the BCM283x family of devices, but a Fix
for a non-existent patch is clearly superfluous. The author of the
original patch can consider this as a hint about the kind of issues that
need to be considered before resubmitting.
Thanks,
Phil
