linux-kernel - RE: [PATCH] clk: imx: imx93: introduce clk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 4 May 2023 09:17:08 +0000
From:   Peng Fan <peng.fan@....com>
To:     Greg KH <greg@...ah.com>, "Peng Fan (OSS)" <peng.fan@....nxp.com>,
        Rob Herring <robh+dt@...nel.org>,
        "krzysztof.kozlowski+dt@...aro.org" 
        <krzysztof.kozlowski+dt@...aro.org>
CC:     "abelvesa@...nel.org" <abelvesa@...nel.org>,
        "mturquette@...libre.com" <mturquette@...libre.com>,
        "sboyd@...nel.org" <sboyd@...nel.org>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "festevam@...il.com" <festevam@...il.com>,
        dl-linux-imx <linux-imx@....com>,
        "linux-clk@...r.kernel.org" <linux-clk@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] clk: imx: imx93: introduce clk_bypassed module parameter

+ DT maintainers.

> Subject: Re: [PATCH] clk: imx: imx93: introduce clk_bypassed module
> parameter
> 
> On Thu, May 04, 2023 at 04:55:06PM +0800, Peng Fan (OSS) wrote:
> > From: Peng Fan <peng.fan@....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.
> 
> 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 = <IMX93_CLK_X>, <IMX93_CLK_Y>" ?

Thanks,
Peng.

> 
> Also, another comment below:
> 
> > @@ -310,6 +357,8 @@ static int imx93_clocks_probe(struct
> > platform_device *pdev)
> >
> >  	for (i = 0; i < ARRAY_SIZE(root_array); i++) {
> >  		root = &root_array[i];
> > +		if (unlikely(imx_clk_bypass_check(root->name)))
> > +			continue;
> 
> 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.
> 
> But as this change isn't needed, this shouldn't be an issue either.
> 
> thanks,
> 
> greg k-h