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Date:   Tue, 9 Aug 2022 09:54:31 +0300
From:   Ivan Bornyakov <i.bornyakov@metrotek.ru>
To:     Daniel =?utf-8?B?R2zDtmNrbmVy?= <dg@emlix.com>
Cc:     mdf@kernel.org, hao.wu@intel.com, yilun.xu@intel.com,
        trix@redhat.com, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, linux-fpga@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        system@metrotek.ru
Subject: Re: [PATCH v5 1/2] fpga: ecp5-spi: add Lattice ECP5 FPGA manager
Message-ID: <20220809065431.nbfopsvx6teja37i@x260>
References: <20220719112335.9528-1-i.bornyakov@metrotek.ru>
 <20220719112335.9528-2-i.bornyakov@metrotek.ru>
 <20220801072448.GA11993@homes.emlix.com>
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On Mon, Aug 01, 2022 at 09:24:49AM +0200, Daniel Gl?ckner wrote:
> Hi,
> 
> On Tue, Jul 19, 2022 at 02:23:34PM +0300, Ivan Bornyakov wrote:
> > +	/* Enter init mode */
> > +	gpiod_set_value(priv->program, 1);
> > +
> > +	ret = ecp5_poll_gpio(priv->init, true);
> > +	if (!ret)
> > +		ret = ecp5_poll_gpio(priv->done, false);
> > +
> > +	if (ret) {
> > +		dev_err(dev, "Failed to go to initialization mode\n");
> > +		return ret;
> > +	}
> 
> To me the documentation looks like the chip will deassert INITN after
> tINITL regardless of the PROGRAMN signal. At 55ns max tINITL is too
> short to reliably sample INITN while it is asserted when we have
> interrupts enabled. Can you confirm that INITN stays asserted as long
> as PROGRAMN is asserted?

I confirm that INITN stays asserted while PROGRAMN is asserted, just
rechecked.