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From:   Peng Fan <peng.fan@nxp.com>
To:     Greg KH <greg@kroah.com>, "Peng Fan (OSS)" <peng.fan@oss.nxp.com>,
        Rob Herring <robh+dt@kernel.org>,
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Subject: RE: [PATCH] clk: imx: imx93: introduce clk_bypassed module parameter
Thread-Topic: [PATCH] clk: imx: imx93: introduce clk_bypassed module parameter
Thread-Index: AQHZfmVsUoWhON65f0ewGxlg24Oc/K9J088AgAAAwyA=
Date:   Thu, 4 May 2023 09:17:08 +0000
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References: <20230504085506.504474-1-peng.fan@oss.nxp.com>
 <2023050410-rejoin-vocation-8560@gregkh>
In-Reply-To: <2023050410-rejoin-vocation-8560@gregkh>
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+ DT maintainers.

> Subject: Re: [PATCH] clk: imx: imx93: introduce clk_bypassed module
> parameter
>=20
> On Thu, May 04, 2023 at 04:55:06PM +0800, Peng Fan (OSS) wrote:
> > From: Peng Fan <peng.fan@nxp.com>
> >
> > With the clk names specified in clk_bypassed module parameter, give
> > user an option to bypass the clk from managing them by Linux kernel.
>=20
> As I said on another email, no, please do not add new module parameters
> for drivers, this is not the 1990s

ok, but this is for boot, so only DT could be considered.

But DT is to describe hardware, here I just wanna give user
an option to bypass some clocks. Is it ok to add a DT property
saying "fsl,imx93-bypass-clks =3D <IMX93_CLK_X>, <IMX93_CLK_Y>" ?

Thanks,
Peng.

>=20
> Also, another comment below:
>=20
> > @@ -310,6 +357,8 @@ static int imx93_clocks_probe(struct
> > platform_device *pdev)
> >
> >  	for (i =3D 0; i < ARRAY_SIZE(root_array); i++) {
> >  		root =3D &root_array[i];
> > +		if (unlikely(imx_clk_bypass_check(root->name)))
> > +			continue;
>=20
> Only ever use likely/unlikely if you can measure the difference.  Here on=
 a
> probe function, you can not, this is not needed at all, the compiler and =
CPU
> will do a better job over time than you can guess at this.
>=20
> But as this change isn't needed, this shouldn't be an issue either.
>=20
> thanks,
>=20
> greg k-h