Re: [Qemu-devel] [PATCH v2] char: cadence: check baud rate generator and divider values

[Alistair Francis <alistair.francis@xilinx.com>]

On Tue, Oct 25, 2016 at 11:50 PM, P J P <ppandit@redhat.com> wrote:
> +-- On Tue, 25 Oct 2016, Alistair Francis wrote --+
> | I think your email crossed with Peter. Have a look at what he said.
> | That should clarify everything.
>
>   I saw, I'll mask values with 0xFFFF and 0xFF; But it's not clear if ignoring
> values 0 - 3, means leaving registers uninitialised and adding checks at each
> usage point to ensure their value is valid. If so, do we return from
> uart_parameters_setup(), when either value is invalid ? Earlier you'd
> suggested using default values
>
>   -> https://lists.gnu.org/archive/html/qemu-devel/2016-10/msg04397.html

>From what I can tell I would say that any writes to the divider
register that have a value lower then 3 are ignored and the register
isn't updated.

That way we will always have a valid value as the register is reset to 0xF.

Thanks,

Alistair

>
> Thank you.
> --
> Prasad J Pandit / Red Hat Product Security Team
> 47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F
>