Re: [Qemu-devel] [PATCH] i.MX: Support serial RS-232 break properly

[Peter Maydell]

On 20 March 2018 at 01:36, Trent Piepho <address@hidden> wrote:
> Linux does not detect a break from this IMX serial driver as a magic
> sysrq.  Nor does it note a break in the port error counts.
>
> The former is because the Linux driver uses the BRCD bit in the USR2
> register to trigger the RS-232 break handler in the kernel, which is
> where sysrq hooks in.  The emulated UART was not setting this status
> bit.
>
> The latter is because the Linux driver expects, in addition to the BRK
> bit, that the ERR bit is set when a break is read in the FIFO.  A break
> should also count as a frame error, so add that bit too.
>
> Cc: Andrey Smirnov <address@hidden>
> Signed-off-by: Trent Piepho <address@hidden>

Yep, the data sheet is nice and clear here about the requirements.

Applied to target-arm.next, thanks.

-- PMM