Re: No GENERIC.hints for aarch64 (arm64?), armv7, and more; also /sys/ based paths are referenced but seem to not be universally standard; also which ARCH standard in path?

On Tue, Feb 18, 2025 at 4:57 PM Mark Millard <[email protected]> wrote:

> On Feb 18, 2025, at 14:01, Warner Losh <[email protected]> wrote:
> >
> > On Tue, Feb 18, 2025 at 2:56 PM Warner Losh <[email protected]> wrote:
> >>
> >> On Sat, Feb 15, 2025 at 10:04 AM Mark Millard <[email protected]>
> wrote:
> >>> [This seems likely to not be limited to main [so: 15 as stands].
> >>> But I'm using main as the example for the issue.]
> >>>
> >>> In:
> >>>
> >>> # man 5 device.hints
> >>> DEVICE.HINTS(5)           FreeBSD File Formats Manual
> DEVICE.HINTS(5)
> >>>
> >>> NAME
> >>>      device.hints – device resource hints
> >>>
> >>> . . .
> >>>
> >>> FILES
> >>>      /boot/device.hints                          Device resource hints
> file.
> >>>      /sys/ARCH/conf/GENERIC.hints                Sample resource hints
> for the
> >>>                                                  GENERIC kernel.
> >>>      /sys/ARCH/conf/NOTES                        Notes on the kernel
> >>>                                                  configuration file
> and device
> >>>                                                  resource hints.
> >>> . . .
> >>>
> >>>
> >>>
> >>> For reference:
> >>>
> >>> # find -s / -name GENERIC.hints -print
> >>> /usr/src/sys/amd64/conf/GENERIC.hints
> >>> /usr/src/sys/i386/conf/GENERIC.hints
> >>> /usr/src/sys/powerpc/conf/GENERIC.hints
> >>>
> >>>
> >>> Multiple points:
> >>>
> >>> ) It seems that aarch64 (arm64?) and armv7 (arm?) have no
> >>>   such GENERIC.hints file. The same goes for riscv64
> >>>   (riscv?).
> >>>
> >>>   The intent for powerpc64 , powerpc64le , and powerpcspe
> >>>   may have the same issue.
> >>>
> >>>
> >>> ) At least for how the local systems were installed, there
> >>>   is no such place predefined as /sys/ , not   even as a
> >>>   symbolic link. "man 7 hier" does not list such.
> >>>
> >>>   So it seems /sys -> /usr/src/sys is intended. (But
> >>>   /usr/src/ need not have been populated, leaving a
> >>>   lack of any GENERIC.hints in such a case.)
> >>>
> >>>   Best to not to depend on /sys in the notation shown?
> >>>
> >>>
> >>> ) The /ARCH/ reference is unclear vs. MACHINE,
> >>>   MACHINE_CPUARCH, and MACHINE_ARCH. The example paths
> >>>   existing for GENERIC.hints do not help because they
> >>>   all allow MACHINE == MACHINE_CPUARCH ,
> >>>   MACHINE == MACHINE_ARCH , and
> >>>   MACHINE_CPUARCH == MACHINE_ARCH. However, based on the
> >>>   NOTE paths:
> >>
> >> Like all things kernel, it's MACHINE.
> >>
> >>>   # find -s /usr/src/ -name NOTES -print | grep /conf/NOTES | more
> >>>   /usr/src/sys/amd64/conf/NOTES
> >>>   /usr/src/sys/arm/conf/NOTES
> >>>   /usr/src/sys/arm64/conf/NOTES
> >>>   /usr/src/sys/conf/NOTES
> >>>   /usr/src/sys/i386/conf/NOTES
> >>>   /usr/src/sys/powerpc/conf/NOTES
> >>>   /usr/src/sys/riscv/conf/NOTES
> >>>   /usr/src/sys/x86/conf/NOTES
> >>>
> >>>   None of of the MACHINE* are right: x86 is not one of
> >>>   any of the 3. Otherwise /arm64/conf/NOTES would suggest
> >>>   MACHINE as the only possibility if /ARCH/ was uniform
> >>>   for relative to the 3 MACHINE* possibilities. So?:
> >>>
> >>>   /usr/src/sys/arm64/conf/GENERIC.hints
> >>>   /usr/src/sys/arm/conf/GENERIC.hints
> >>>   /usr/src/sys/riscv/conf/GENERIC.hints
> >>>
> >>>   with no aarch64 , armv7 , powerpc64* , powerpcspe , or
> >>>   riscv64 examples?
> >>
> >> We store these in /dev/null these days :).
> >>
> >> I'll create empty ones for this.
> >
> >  https://reviews.freebsd.org/D49052
>
> Thanks.
>
> > Just to expand a little: These platforms don't have legacy devices
> > they need to hard-wire in various ways, unlike the other platforms.
> > However, people use them to do device instance wiring, so I've created
> > the empty ones.
>
> An example can also be disabling something that needs to be avoided
> for some unusual reason, such as avoiding virtio_gpu under parallels
> on aarch64 macOS. (I've not tested doing that yet.)
>

I'm open to commenting out such things.

Warner