On Tuesday 31 January 2017 07:59:18 Tony Lindgren wrote: > * Kalle Valo <kvalo@xxxxxxxxxxxxxx> [170130 22:36]: > > Tony Lindgren <tony@xxxxxxxxxxx> writes: > > > > > * Pavel Machek <pavel@xxxxxx> [170127 11:41]: > > >> On Fri 2017-01-27 17:23:07, Kalle Valo wrote: > > >> > Pali Rohár <pali.rohar@xxxxxxxxx> writes: > > >> > > > >> > > On Friday 27 January 2017 14:26:22 Kalle Valo wrote: > > >> > >> Pali Rohár <pali.rohar@xxxxxxxxx> writes: > > >> > >> > > >> > >> > 2) It was already tested that example NVS data can be used for N900 e.g. > > >> > >> > for SSH connection. If real correct data are not available it is better > > >> > >> > to use at least those example (and probably log warning message) so user > > >> > >> > can connect via SSH and start investigating where is problem. > > >> > >> > > >> > >> I disagree. Allowing default calibration data to be used can be > > >> > >> unnoticed by user and left her wondering why wifi works so badly. > > >> > > > > >> > > So there are only two options: > > >> > > > > >> > > 1) Disallow it and so these users will have non-working wifi. > > >> > > > > >> > > 2) Allow those data to be used as fallback mechanism. > > >> > > > > >> > > And personally I'm against 1) because it will break wifi support for > > >> > > *all* Nokia N900 devices right now. > > >> > > > >> > All two of them? :) > > >> > > >> Umm. You clearly want a flock of angry penguins at your doorsteps :-). > > > > > > Well this silly issue of symlinking and renaming nvs files in a standard > > > Linux distro was also hitting me on various devices with wl12xx/wl18xx > > > trying to use the same rootfs. > > > > > > Why don't we just set a custom compatible property for n900 that then > > > picks up some other nvs file instead of the default? > > > > Please don't. An ugly kernel workaround in kernel because of user space > > problems is a bad idea. wl1251 should just ask for NVS file from user > > space, it shouldn't care if it's a "default" file or something else. > > That's a user space policy decision. > > Grr I keep forgetting it needs to be for each device manufactured so > yeah that won't work. > > The names of standard distro files are hardcoded into the kernel > driver so it's also a kernel problem though :p > > How about a custom devices tree property saying "needs-custom-firmware"? How does it help request_firmware() call which automatically loads firmware file from VFS (if is available)? > Something that would prevent anything being loaded until user space > loads the firmware. It could also be set in the driver automatically > based on the compatible flag if we always want it enabled. And we could > have some cmdline option to ignore it. Or the other way around whatever > makes sense. So you just want to kernel automatically prevent loading firmware file (based on flag which driver can set). That is similar approach as mine. > > Why can't you do something like this: > > > > * rename the NVS file linux-firmware to wl1251-nvs.bin.example > > As that name is hardcoded in the kernel and that file is provided by > all standard distros, let's assume we just have to deal with that ABI > forever. Yes. > > * before distro updates linux-firmware create yours own deb/rpm/whatever > > package "wl1251-firmware" which installs your flavor of nvs file (or > > the user fallback helper if more dynamic functionality is preferred) > > And that won't work when using the same file system on other machines. > > Think NFSroot for example. At least I'm using the same NFSroot across > about 15 different machines including one n900 macro board with smc91x > Ethernet. Exactly problem which we already discussed in previous emails. You cannot serve one file (loaded by direct request_firmware) when your rootfs is readonly, e.g. comes via NFS shared for more devices... -- Pali Rohár pali.rohar@xxxxxxxxx
