From mboxrd@z Thu Jan  1 00:00:00 1970
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] serial: 8250_dw: support high baudrates if possible
Date: Sat, 28 Jun 2014 16:36:08 +0100
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Cc: gregkh@linuxfoundation.org, heikki.krogerus@linux.intel.com, david.daney@cavium.com, loic.poulain@intel.com, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org

On Fri, 27 Jun 2014 12:25:20 -0500
> +		rate = 16 * max(115200U, (unsigned int)baud);
> +

This assumes an arbitarily configurable clock, which is not I think the
usual case. 
> +		/*
> +		 * Request a different clock rate if necessary, and
> +		 * record it if successful.
> +		 */
> +		if (rate != p->uartclk) {
> +			BUG_ON(!data->clk);
> +			if (!clk_set_rate(data->clk, (unsigned long)rate))
> +				p->uartclk = rate;
> +		}