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Date:   Fri, 23 Sep 2022 10:16:38 +0300
From:   Ivan Bornyakov <i.bornyakov@metrotek.ru>
To:     Xu Yilun <yilun.xu@intel.com>
Cc:     mdf@kernel.org, hao.wu@intel.com, trix@redhat.com, dg@emlix.com,
        j.zink@pengutronix.de, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, linux-fpga@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel@pengutronix.de, system@metrotek.ru
Subject: Re: [PATCH v12 1/2] fpga: lattice-sysconfig-spi: add Lattice
 sysCONFIG FPGA manager
Message-ID: <20220923071638.45hylqvajn74j6mk@h-e2.ddg>
References: <20220919134750.25197-1-i.bornyakov@metrotek.ru>
 <20220919134750.25197-2-i.bornyakov@metrotek.ru>
 <Yy1RLvxTJhGUuJJ2@yilunxu-OptiPlex-7050>
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In-Reply-To: <Yy1RLvxTJhGUuJJ2@yilunxu-OptiPlex-7050>
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On Fri, Sep 23, 2022 at 02:24:46PM +0800, Xu Yilun wrote:
> On 2022-09-19 at 16:47:49 +0300, Ivan Bornyakov wrote:
> > Add support to the FPGA manager for programming Lattice ECP5 FPGA over
> > slave SPI sysCONFIG interface.
> > 
> > sysCONFIG interface core functionality is separate from both ECP5 and
> > SPI specifics, so support for other FPGAs with different port types can
> > be added in the future.
> > 
> > Signed-off-by: Ivan Bornyakov <i.bornyakov@metrotek.ru>
> > ---
> >  drivers/fpga/Kconfig                 |  11 +
> >  drivers/fpga/Makefile                |   2 +
> >  drivers/fpga/lattice-sysconfig-spi.c | 153 ++++++++++
> >  drivers/fpga/lattice-sysconfig.c     | 408 +++++++++++++++++++++++++++
> >  drivers/fpga/lattice-sysconfig.h     |  40 +++
> >  5 files changed, 614 insertions(+)
> >  create mode 100644 drivers/fpga/lattice-sysconfig-spi.c
> >  create mode 100644 drivers/fpga/lattice-sysconfig.c
> >  create mode 100644 drivers/fpga/lattice-sysconfig.h
> > 
> > diff --git a/drivers/fpga/lattice-sysconfig-spi.c b/drivers/fpga/lattice-sysconfig-spi.c
> > new file mode 100644
> > index 000000000000..d015b796adf7
> > --- /dev/null
> > +++ b/drivers/fpga/lattice-sysconfig-spi.c
> > 
> > ... snip ...
> > 
> > +static int sysconfig_isc_enable(struct sysconfig_priv *priv)
> > +{
> > +	u8 isc_enable[] = SYSCONFIG_ISC_ENABLE;
> > +	u32 status;
> > +	int ret;
> > +
> > +	ret = sysconfig_cmd_write(priv, isc_enable, sizeof(isc_enable));
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = sysconfig_poll_status(priv, &status);
> > +	if (ret || (status & SYSCONFIG_STATUS_FAIL))
> > +		return ret ? : -EFAULT;
> 
> If (ret == 0 && status == SYSCONFIG_STATUS_FAIL), still return 0?
> 

No, -EFAULT should be returned in that case. Am I overlooked something?

> > +
> > +	return 0;
> > +}
> > +
> > +static int sysconfig_isc_erase(struct sysconfig_priv *priv)
> > +{
> > +	u8 isc_erase[] = SYSCONFIG_ISC_ERASE;
> > +	u32 status;
> > +	int ret;
> > +
> > +	ret = sysconfig_cmd_write(priv, isc_erase, sizeof(isc_erase));
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = sysconfig_poll_status(priv, &status);
> > +	if (ret || (status & SYSCONFIG_STATUS_FAIL))
> 
> Same concern.
> 
> > +		return ret ? : -EFAULT;
> > +
> > +	return 0;
> > +}