Messages in this thread | | | From | "Charles Garcia-Tobin" <> | Subject | RE: [PATCH v5 18/18] Documentation: ACPI for ARM64 | Date | Tue, 6 Jan 2015 14:37:58 -0000 |
| |
> -----Original Message----- > From: Catalin Marinas [mailto:catalin.marinas@arm.com] > Sent: 06 January 2015 14:17 > To: Arnd Bergmann > Cc: linux-arm-kernel@lists.infradead.org; hanjun.guo@linaro.org; Mark > Rutland; linaro-acpi@lists.linaro.org; Will Deacon; Lv Zheng; Rob > Herring; Lorenzo Pieralisi; Al Stone; Daniel Lezcano; Robert Moore; > linux-acpi@vger.kernel.org; jcm@redhat.com; grant.likely@linaro.org; > Charles Garcia-Tobin; Robert Richter; Jason Cooper; Marc Zyngier; Liviu > Dudau; Mark Brown; Bjorn Helgaas; graeme.gregory@linaro.org; > Kangkang.Shen@huawei.com; Randy Dunlap; Rafael J. Wysocki; linux- > kernel@vger.kernel.org; Sudeep Holla; Olof Johansson > Subject: Re: [PATCH v5 18/18] Documentation: ACPI for ARM64 > > On Tue, Jan 06, 2015 at 02:05:12PM +0000, Arnd Bergmann wrote: > > On Tuesday 06 January 2015 11:29:29 Catalin Marinas wrote: > > > > >> We will work on this both on ASWG and linux ACPI driver side, > as Dong > > > > >> and Charles pointed out, _OSI things can be solved in ACPI > spec, when > > > > >> that is done, we can modify the kernel driver to fix the > problems above. > > > > > > > > > > Which driver? > > > > > > > > the ACPICA core driver as you suggested, sorry for the confusion. > > > > > > > > > What about ACPI_OS_NAME? Would you suggest it is fine to report > > > > > "Microsoft Windows NT" on an ARM system? That _OS_ not _OSI. > > > > > > > > No, not at all. I prefer "Linux" > > > > In include/acpi/acconfig.h, when ACPI_OS_NAME defined, it says: > > > > "OS name, used for the _OS object. The _OS object is essentially > > > > obsolete,..." > > > > for some legacy reasons, we needed "Microsoft Windows NT", but > ACPI > > > > for ARM64 on linux is totally new, I think we can change it to > > > > "Linux" when CONFIG_ARM64 as you suggested. > > > > > > We could ignore this change for now if we don't expect the _OS > object to > > > be used at all. But do we have any other way to check the AML code > for > > > this? Would FWTS catch such obsolete cases? > > > > How about just leaving it out? It's clearly not used for anything > > good, so I don't see the point in passing either Linux or "Microsoft > > Windows NT" here. > > Do you mean defining it to NULL (so it ends up as NULL in > acpi_gbl_pre_defined_names) or removing "_OS_" entirely from that > array? > I really can't tell what the implications are.
To me, given that we don't want to use it in ARM64, it would make sense to have some method to configurably: 0. Leave as is 1. Warn for usage 2. Panic With a configurability method that allows FWTS to make use of it, and therefore catch usages of the method.
Cheers
Charles
> > -- > Catalin
| |