From mboxrd@z Thu Jan 1 00:00:00 1970 From: vineet.gupta1@synopsys.com (Vineet Gupta) Date: Wed, 19 Dec 2018 16:51:59 -0800 Subject: [PATCH 00/21] glibc port to ARC processors In-Reply-To: References: <1545167083-16764-1-git-send-email-vgupta@synopsys.com> <228be09c-0d23-d77c-ab45-0ffb69f7f5a1@synopsys.com> List-ID: Message-ID: <89503516-ce73-0749-4290-31dd932b496d@synopsys.com> To: linux-snps-arc@lists.infradead.org On 12/19/18 4:14 PM, Joseph Myers wrote: > On Wed, 19 Dec 2018, Vineet Gupta wrote: > >> On 12/18/18 3:11 PM, Joseph Myers wrote: >>> Another general point: when posting a new port, could you include pointers >>> to architecture and ABI reference manuals in case those are of relevance >>> to the review? (URLs going directly to PDFs of those manuals are >>> preferred.) >> >> The PRM (Programmer's Reference Manual) is not open source and per corporate >> policy requires license agreement, signing NDA... > > It's very questionable whether we should consider a port for inclusion in > glibc at all without public architecture documentation IMHO this seems excessive. We've successfully open-sourced significant ports such as Linux kernel, gcc, binutils etc. gcc atleast deals with instruction semantics at a much closer level than glibc perse and that didn't get in the way then. Being an open source developer myself I agree with your reservations, but the reality is what Ted Tso so nicely put in at [1] | "It's something I do worry about; and I do share your concern. At the | same time, the reality is that we are a little like the Old Dutch | Masters, who had take into account the preference of their patrons | (i.e., in our case, those who pay our paychecks :-)" [1] https://lwn.net/Articles/446626/ > (that is, > documentation of instruction semantics; not necessarily documentation of > microarchitectural performance characteristics etc.). I understand the intent is all good faith and justified... > Various kinds of > changes can require a developer to refer to documentation across the range > of architectures supported by glibc, if something requires assembly > implementations across architectures (e.g. some of Adhemerval's changes to > thread cancellation; or when I added fegetmode / fesetmode, that required > referring to various architecture documentation to identify what bits > should be considered mode bits, on each architecture where floating-point > status and control bits occupy a single register). To be honest folks on lkml do sweeping arch changes, PeterZ is one good example and he has infact changed ARC assembly at times w/o access to PRM. Given the arrangement we have now, perhaps such changes can call in for review from port maintainer etc. > (Non-NDA click-throughs, like the Arm one agreeing not to use the manual > to find if Arm implementations violate any patents, are OK No that is not possible: I've discussed this with power may-be in the past and again today and this is not going to happen. Thx, -Vineet