From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Subject: Re: [RFC][PATCH] at91_ide driver
Date: Thu, 22 Jan 2009 16:38:58 +0300
Message-ID: <497876F2.3070405@ru.mvista.com>
References: <200901141345.42583.stf_xl@wp.pl> <497863B6.4040306@ru.mvista.com> <49786572.1030408@ru.mvista.com> <200901221357.27247.stf_xl@wp.pl>
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Sender: linux-ide-owner@vger.kernel.org
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To: Stanislaw Gruszka <stf_xl@wp.pl>
Cc: Andrew Victor <linux@maxim.org.za>, Nicolas Ferre <nicolas.ferre@atmel.com>, Haavard Skinnemoen <haavard.skinnemoen@atmel.com>, linux-ide@vger.kernel.org

Stanislaw Gruszka wrote:

>>>>>>>+            t9 = t2i - t1;

>>>>>>   It  more sense to calculate such things *after* quantizing the 
>>>>>>timings with calc_mck_cycles()...

>>>>>Why?

>>>>  More precise result -- matching the clock being used.

>>>  However, I don't understand now why you need to stretch t9...

>>  Ah, I do again. t0 *should be equal* to t1 + t2 + t9 for the better 
>>speeds.

    Moreover, t1 + t2 + t9 must be no less that t0 minimum, otherwise it would 
be a timing violation.

> And hold time should meet min t2i requirement, so t9 = max(t9_orig, t2i - t1).

    There's no direct connection between these in ATA/CF specs.

> Stanislaw Gruszka

WBR, Sergei