Re: [PATCH V2 4/9] arch: mips: ralink: add tty detection

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 11/5/2015 5:59 AM, John Crispin wrote:

> MT7688 has several uarts that can be used for console. There are several
> boards in the wild, that use ttyS1 or ttyS2. This patch applies a simply
> autodetection routine to figure out which ttyS the bootloader used as
> console. The uarts come up in 6 bit mode by default. The bootloader will
> have set 8 bit mode on the console. Find that 8bit tty and use it.
>
> Signed-off-by: John Crispin <blogic@openwrt.org>
> ---
> Changes in V2:
> * remove superflous inline definition
>
>   arch/mips/ralink/early_printk.c |   26 ++++++++++++++++++++++++++
>   1 file changed, 26 insertions(+)
>
> diff --git a/arch/mips/ralink/early_printk.c b/arch/mips/ralink/early_printk.c
> index 255d695..3c59ffe 100644
> --- a/arch/mips/ralink/early_printk.c
> +++ b/arch/mips/ralink/early_printk.c
[...]
> @@ -47,8 +49,32 @@ static inline int soc_is_mt7628(void)
>   		(__raw_readl(chipid_membase) == MT7628_CHIP_NAME1);
>   }
>
> +static void find_uart_base(void)
> +{
> +	int i;
> +
> +	if (!soc_is_mt7628())
> +		return;
> +
> +	for (i = 0; i < 3; i++) {
> +		u32 reg = uart_r32(UART_REG_LCR + (0x100 * i));

    Inner parens not needed, the operator precedence is natural.

> +
> +		if (!reg)
> +			continue;
> +
> +		uart_membase = (__iomem void *) KSEG1ADDR(EARLY_UART_BASE +
> +							  (0x100 * i));

    Likewise.
    Sorry for not noticing this before.

MBR, Sergei