From mboxrd@z Thu Jan 1 00:00:00 1970 From: lorenzo.pieralisi@arm.com (Lorenzo Pieralisi) Date: Wed, 22 Jan 2014 16:23:14 +0000 Subject: [PATCH RFC v2 2/2] Documentation: arm: define DT C-states bindings In-Reply-To: <20140122115214.GG17314@sirena.org.uk> References: <1390240079-6495-1-git-send-email-lorenzo.pieralisi@arm.com> <1390240079-6495-3-git-send-email-lorenzo.pieralisi@arm.com> <20140121133148.GB28801@e102568-lin.cambridge.arm.com> <20140121152358.GD28801@e102568-lin.cambridge.arm.com> <20140122115214.GG17314@sirena.org.uk> Message-ID: <20140122162313.GE24288@e102568-lin.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Mark, On Wed, Jan 22, 2014 at 11:52:14AM +0000, Mark Brown wrote: > On Tue, Jan 21, 2014 at 03:23:59PM +0000, Lorenzo Pieralisi wrote: > > On Tue, Jan 21, 2014 at 02:35:11PM +0000, Amit Kucheria wrote: > > > > DT-newbie here. What would happen if a vendor does not characterise > > > the latency at each OPP? IOW, the table only contains latency values > > > for a subset of the OPPs. > > > The bindings are explicit, so the kernel will barf. Adding a LUT to map > > latencies to OPPs make me cringe, so I would not change the current > > bindings. > > Actually looking at the OPP binding I do wonder if it might not be > better to have a v2/rich binding for them which is extensible - the fact > that it's not possible to add additional information seems like an > issue, this can't be the only thing anyone might want to add and lining > up multiple tables is never fun. On one hand OPP bindings need improvement and that's on the cards. I am not really following what you mean by "extensible", I only want to make sure that the C-state bindings do not become too complex. Do you mean extending OPP bindings to add eg C-state information there (or whatever piece of information that is OPP dependent) ? It seems a bit of a stretch but I can think about that. I think that C-state properties are better defined in the C-state bindings that was the idea but I am open to suggestions. Thank you ! Lorenzo