[U-Boot] [PATCH 2/3] x86: BayTrail: Add function to disable the internal legacy UART

[Bin Meng]

Hi Stefan,

On Tue, Jan 19, 2016 at 4:40 PM, Bin Meng <bmeng.cn at gmail.com> wrote:
> Hi Stefan,
>
> On Mon, Jan 18, 2016 at 5:56 PM, Stefan Roese <sr at denx.de> wrote:
>> Some BayTrail boards may want to use a different legacy UART than the
>> internal one. E.g. one provided by a Winbond Super IO chip, like the
>> W83627. This patch adds a function to disable this BayTrail internal
>> UART for this purpose.
>>
>> Signed-off-by: Stefan Roese <sr at denx.de>
>> Cc: Bin Meng <bmeng.cn at gmail.com>
>> Cc: Simon Glass <sjg at chromium.org>
>> ---
>>  arch/x86/cpu/baytrail/early_uart.c | 9 +++++++++
>>  arch/x86/include/asm/u-boot-x86.h  | 3 +++
>>  2 files changed, 12 insertions(+)
>>
>> diff --git a/arch/x86/cpu/baytrail/early_uart.c b/arch/x86/cpu/baytrail/early_uart.c
>> index b64a3a9..716783c 100644
>> --- a/arch/x86/cpu/baytrail/early_uart.c
>> +++ b/arch/x86/cpu/baytrail/early_uart.c
>> @@ -76,3 +76,12 @@ int setup_early_uart(void)
>>
>>         return 0;
>>  }
>> +
>> +int disable_internal_uart(void)
>> +{
>> +       /* Disable the legacy UART hardware. */
>
> nits: please remove the ending peirod.
>
>> +       x86_pci_write_config32(PCI_DEV_CONFIG(0, LPC_DEV, LPC_FUNC), UART_CONT,
>> +                              0);
>> +
>> +       return 0;
>> +}
>> diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h
>> index dbf8e95..0c95796 100644
>> --- a/arch/x86/include/asm/u-boot-x86.h
>> +++ b/arch/x86/include/asm/u-boot-x86.h
>> @@ -47,6 +47,9 @@ int default_print_cpuinfo(void);
>>  /* Set up a UART which can be used with printch(), printhex8(), etc. */
>>  int setup_early_uart(void);
>>
>> +/* Disable the internal legacy UART */
>> +int disable_internal_uart(void);

If we can call disable_internal_uart() in board-specific codes, then
this declaration can be moved to SoC-specific header instead of x86
generic one.

>> +
>>  void setup_pcat_compatibility(void);
>>
>>  void isa_unmap_rom(u32 addr);
>> --
>
> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>

Regards,
Bin