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Date:   Mon, 5 Jul 2021 10:48:23 -0400
From:   Ralph Siemsen <ralph.siemsen@linaro.org>
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     linux-mtd <linux-mtd@lists.infradead.org>,
        Marek Vasut <marex@denx.de>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] mtd: rawnand: denali: add more delays before latching
 incoming data
Message-ID: <20210705144823.GA1459782@maple.netwinder.org>
References: <20200317071821.9916-1-yamada.masahiro@socionext.com>
 <20210630184741.GA1037365@maple.netwinder.org>
 <CAK7LNASvYVyEQ4M_zEUdw9K9AB-RVErKoqFMQZ5OSKJF0AoBww@mail.gmail.com>
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On Mon, Jul 05, 2021 at 01:00:43AM +0900, Masahiro Yamada wrote:
>
>I no longer have any hardware to test this driver.
>
>If you increase data_setup_on_host (the current value is 10000),
>will it solve your issue?

Yes, it does seem to work with this value increased to 10001.

Looking more closely, I compared timing parameters in struct 
denali_chip_sel, for the kernel 5.4 (which works), for 5.10 (which 
fails), and also for 5.10 with data_setup_host=10001 (which works).

                 5.4     5.10    5.10+10001
acc_clks        2       3       4
rdwr_en_lo_cnt  3       2       3
cs_setup_cnt    1       0       0

So it seems that on my hardware, rdwr_en_lo_cnt must be >= 3.

Regards,
Ralph