[PATCH] 8250: add workaround for MPC8[356]xx UART break IRQ storm

[Kumar Gala]

On Feb 26, 2010, at 1:25 PM, Paul Gortmaker wrote:

> Sending a break on the SOC UARTs found in some MPC83xx/85xx/86xx
> chips seems to cause a short lived IRQ storm (/proc/interrupts
> typically shows somewhere between 300 and 1500 events).  Unfortunately
> this renders SysRQ over the serial console completely inoperable.
> Testing with obvious things like ACKing the event doesn't seem to
> change anything vs. a completely dumb approach of just ignoring
> it and waiting for it to stop, so that is what is implemented here.
> 
> Signed-off-by: Paul Gortmaker <paul.gortmaker at windriver.com>
> ---
> 
> This is a refresh of a patch I'd done earlier -- I've tried to make
> the bug support as generic as possible to minimize having board
> specific ifdef crap in 8250.c -- any suggestions on how to further
> improve it are welcome.
> 
> drivers/serial/8250.c      |    6 ++++++
> drivers/serial/8250.h      |   20 ++++++++++++++++++++
> drivers/serial/Kconfig     |   14 ++++++++++++++
> include/linux/serial_reg.h |    2 ++
> 4 files changed, 42 insertions(+), 0 deletions(-)

Did we ever decide what to do with this or trying to get it accepted upstream?

- k