From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marex@denx.de>
Date: Fri, 14 Sep 2012 20:05:12 +0200
Subject: [U-Boot] [PATCH v2 04/11] serial: Use a more precise baud rate
	generation for serial_s3c24x0
In-Reply-To: <1347643742-19966-5-git-send-email-jose.goncalves@inov.pt>
References: <1347643742-19966-1-git-send-email-jose.goncalves@inov.pt>
	<1347643742-19966-5-git-send-email-jose.goncalves@inov.pt>
Message-ID: <201209142005.12736.marex@denx.de>
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To: u-boot@lists.denx.de

Dear Jos? Miguel Gon?alves,

> Program udivslot register in order to obtain a more precise baudrate.

More explanatory commit message would be nice.

[...]

> +static const int udivslot[] = {

const array const members, no ?

> +	0x0000, 0x0080, 0x0808, 0x0888, 0x2222, 0x4924, 0x4A52, 0x54AA,
> +	0x5555, 0xD555, 0xD5D5, 0xDDD5, 0xDDDD, 0xDFDD, 0xDFDF, 0xFFDF,
> +};
> +
>  void _serial_setbrg(const int dev_index)
>  {
>  	struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
> -	unsigned int reg = 0;
> +	u32 pclk;
> +	u32 baudrate;
>  	int i;
> 
> -	/* value is calculated so : (int)(PCLK/16./baudrate) -1 */
> -	reg = get_PCLK() / (16 * gd->baudrate) - 1;
> +	pclk = get_PCLK();
> +	baudrate = gd->baudrate;
> 
> -	writel(reg, &uart->ubrdiv);
> +	writel((pclk / baudrate / 16) - 1, &uart->ubrdiv);
> +	writel(udivslot[(pclk / baudrate) % 16], &uart->udivslot);
>  	for (i = 0; i < 100; i++)
>  		/* Delay */ ;
>  }

Best regards,
Marek Vasut