[U-Boot] [PATCH 1/1] serial/ns16550: check UART mode for TEMT value

[Tom Rini]

On Wed, Jan 2, 2013 at 9:58 PM, Scott Wood <scottwood at freescale.com> wrote:
> On 12/23/2012 05:17:25 PM, Javier Martinez Canillas wrote:
>>
>> On Sat, Dec 22, 2012 at 4:40 AM, Javier Martinez Canillas
>> <javier.martinez at collabora.co.uk> wrote:
>> >
>> > But if I'm the only one having this issue maybe is just my hardware
>> > behaving
>> > badly. I'll ask other OMAP3 users if they can boot with mainline U-Boot
>> > to
>> > confirm this.
>> >
>>
>> Hello,
>>
>> I tested with an Beagleboard which is another OMAP3 board that has the
>> same PC16550D UART than my OMAP3 IGEPv2 and the board does not hang
>> while waiting for TEMT. I've also tested with an OMAP4 pandaboard and
>> it boots correctly too.
>>
>> But the hung issue seems to not be an issue with my IGEPv2 board but
>> with any IGEPv2 board since another user reported that his board hangs
>> with the latest U-Boot too. Reverting cb55b332 (serial/ns16550: wait
>> for TEMT before initializing) solved the issue for him.
>>
>> Will a patch like this be an acceptable solution?
>>
>> diff --git a/drivers/serial/ns16550.c b/drivers/serial/ns16550.c
>> index bbd91ca..8106a9a 100644
>> --- a/drivers/serial/ns16550.c
>> +++ b/drivers/serial/ns16550.c
>> @@ -36,8 +36,10 @@
>>
>>  void NS16550_init(NS16550_t com_port, int baud_divisor)
>>  {
>> +#if (CONFIG_MACH_TYPE != MACH_TYPE_IGEP0020)
>>         while (!(serial_in(&com_port->lsr) & UART_LSR_TEMT))
>>                 ;
>> +#endif
>
>
> Probably better to have your board config file define
> CONFIG_SYS_NS16550_BROKEN_TEMT or similar (and document the symbol in
> README).

To be clear, yes, please, that way.  Thanks!

--
Tom