Re: [PATCH v3 3/3] serial: 8250_em: Add serial_out() to struct serial8250_em_hw_info

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Fri, Feb 10, 2023 at 08:34:39PM +0000, Biju Das wrote:
> As per HW manual section 40.6.1, we need to perform FIFO reset + SW
> reset before updating the below registers.
> 
> FCR[7:5], FCR[3:0], LCR[7][5:0], MCR[6:4], DLL[7:0], DLM[7:0] and
> HCR0[6:5][3:2].
> 
> This patch adds serial_out() to struct serial8250_em_hw_info to
> handle this difference between emma mobile and rz/v2m.
> 
> DLL/DLM register can be updated only by setting LCR[7]. So the
> updation of LCR[7] will perform reset for DLL/DLM register changes.

...

>  #define UART_DLL_EM 9
>  #define UART_DLM_EM 10
> +#define UART_HCR0 11

Can we continue using _EM suffix?

...

> +	/*
> +	 * The value of UART_IIR and UART_FCR are 2, but corresponding
> +	 * RZ/V2M address offset are different(0x08 and 0x0c). So we need to
> +	 * use readl() here.
> +	 */
> +	fcr = readl(p->membase + ((UART_FCR + 1) << 2));

So, what does prevent you to define above

#define UART_IIR_EM	3 // or whatever name it should have

and use again same helper here?

-- 
With Best Regards,
Andy Shevchenko