netdev - Re: [PATCH net-next 4/5] net/fsl: xgmac_mdio: Support setting the MDC frequency

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <YfFUhn+T2SYCaTHc@lunn.ch>
Date:   Wed, 26 Jan 2022 15:02:46 +0100
From:   Andrew Lunn <andrew@...n.ch>
To:     Tobias Waldekranz <tobias@...dekranz.com>
Cc:     davem@...emloft.net, kuba@...nel.org, netdev@...r.kernel.org,
        Marcin Wojtas <mw@...ihalf.com>,
        Calvin Johnson <calvin.johnson@....nxp.com>,
        Markus Koch <markus@...syncing.net>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH net-next 4/5] net/fsl: xgmac_mdio: Support setting the
 MDC frequency

> >> +	if (device_property_read_u32(dev, "clock-frequency", &priv->mdc_freq))
> >> +		return;
> >> +
> >> +	priv->enet_clk = devm_clk_get(dev, NULL);
> >> +	if (IS_ERR(priv->enet_clk)) {
> >> +		dev_err(dev, "Input clock unknown, not changing MDC frequency");
> >
> > Is the clock optional or mandatory?
> 
> As the code is now, it is mandatory. I could add some default frequency,
> but I fear that could do more harm than good?

As i said in the reply to the DT patch, it is mandatory if the
"clock-frequency" parameter is present.

> Ok, no worries about regressions for deployed stuff already out there?

It would only cause a regression if a DT blob happened to have a
'clock-frequency' parameter and not clock, which it should not.

        Andrew