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
| ||
|
Date: Fri, 29 Jul 2022 08:50:36 +0200 From: Maxime Chevallier <maxime.chevallier@...tlin.com> To: Florian Fainelli <f.fainelli@...il.com> Cc: Andrew Lunn <andrew@...n.ch>, davem@...emloft.net, Rob Herring <robh+dt@...nel.org>, netdev@...r.kernel.org, linux-kernel@...r.kernel.org, devicetree@...r.kernel.org, thomas.petazzoni@...tlin.com, Heiner Kallweit <hkallweit1@...il.com>, Russell King <linux@...linux.org.uk>, linux-arm-kernel@...ts.infradead.org, Horatiu.Vultur@...rochip.com, Allan.Nielsen@...rochip.com, UNGLinuxDriver@...rochip.com Subject: Re: [PATCH net-next 3/4] net: phy: Add helper to derive the number of ports from a phy mode Hello Florian, Andrew, On Thu, 28 Jul 2022 14:44:47 -0700 Florian Fainelli <f.fainelli@...il.com> wrote: > On 7/28/22 14:32, Andrew Lunn wrote: > >> +int phy_interface_num_ports(phy_interface_t interface) > >> +{ > >> + switch (interface) { > >> + case PHY_INTERFACE_MODE_NA: > >> + case PHY_INTERFACE_MODE_INTERNAL: > >> + return 0; > > > > I've not yet looked at how this is used. Returning 0 could have > > interesting effects i guess? INTERNAL clearly does have some sort of > > path between the MAC and the PHY, so i think 1 would be a better > > value. NA is less clear, it generally means Don't touch. But again, > > there still needs to be a path between the MAC and PHY, otherwise > > there would not be any to touch. > > > > Why did you pick 0? My reasonning was that PHY_INTERNAL is likely a custom solution to link IPs existing on the same die, so nothing prevents vendors from multiplexing links on that interface. But it's a far-fetched reasonning, so 1 can be good, as other interfaces that are meant to be used on-die like XGMII. > I would agree that returning 1 is a more sensible default to avoid > breaking users of that function. However this makes me wonder, in > what case will we break the following common meaning: > > - Q -> quad > - P -> penta > - O -> octal > > Is the helper really needed in the sense that the phy_interface_t > enumeration is explicit enough thanks to or because of its name? -- > Florian Good question actually ! It started as a point from Russell proposing a helper to get the number of serdes lanes for a given interface, but this sisn't quite fit the use-case, which was simply to simplify if (interface == PHY_INTERFACE_MODE_QSGMII || interface == PHY_INTERFACE_MODE_QUSGMII) into if (phy_interface_num_ports(interface) == 4) But this a slim simplification at the cost of a new helper to maintain, so I can repove that if you want. Thanks for the reviews, Maxime
Powered by blists - more mailing lists