-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Somebody in the thread at some point said: | Hi Andy, | |> Just curious about this "machine name" concept, what does it actually |> address?
Thanks for the info. | This is what you give to OE as the MACHINE settings, it defines things like | * jffs2 params for the rootfs This is highly raw NAND specific. | * flash size Outside of special case of onboard raw NAND, today storage sizes are bigger to the point it doesn't need to be a real consideration for rootfs configuration. Not trying to invalidate the need to work with this for devices that have no choice, just saying that going on raw NAND constraint is not necessarily a major factor. | * serial tty setting Bootloader has to typically know this: it could export the knowledge. | * preferred X server | * machine capabilities in general (phone, screen, keyboard, usbhost, ...) To some or complete extent chosen kernel has to know this, could export it. If there's a choice, which kernel chosen is again a bootloader decision. | This MACHINE setting is also used as OVERRIDE for config file in packages such | as: | | [EMAIL PROTECTED]:/local/pkg/oe/openembedded$ find . -name om-gta01 | ./packages/scummvm/files/om-gta01 | ./packages/uclibc/uclibc-0.9.29/om-gta01 | ./packages/uclibc/uclibc-0.9.30/om-gta01 uClibc cares? | ./packages/netbase/netbase/om-gta01 | ./packages/u-boot/u-boot-1.2.0/om-gta01 Yes can't avoid that, bootloader for 2410 and 2442 or 6410 are different. But it could determine what's righteous by inheriting something from the bootloader that started Linux. | ./packages/base-files/base-files/om-gta01 Can't guess why that one exists. | ./packages/tslib/tslib/om-gta01 Or that one, it is the same LCM. | ./packages/gpephone/gpe-applauncher/om-gta01 No real idea. | ./packages/gpsd/files/om-gta01 Yes different GPS chip needs a binary blob. | ./packages/pointercal/files/om-gta01 Again it's the same LCM. | ./packages/freesmartphone/frameworkd/om-gta01 Dunno, is it /sys? | ./packages/openmoko2/openmoko-dialer2/om-gta01 Same calypso stuff needs different package? | ./packages/initscripts/initscripts-1.0/om-gta01 Dunno what the difference can be. | ./packages/fbset/fbset-modes/om-gta01 Guess it's something to do with direct LCD controller vs Glamo, but still hard to guess exactly what since it is same LCM and we use fbset / framebuffer kernel driver to abstract it all. |> It has become clear lately that we need single rootfs image |> that deals with several types of device, is that what it actually does? | | While a single rootfs image is very appealing, our experience says it only | works well on device families where the siblings are _very_ related. Underpinning all this is need for instruction set compatibility, ie, can eat armv4. After that, I think we find everything can be runtime determined (via cpu-specific bootloader + device-specific kernel) | (It may work for gta01 and gta02, but we're also talking about machines like | the Motorola EZX series here or the Zaurus family which have dozens of | somewhat similar, but still too different variants) | | Of course you can try to achieve most of this with runtime configuration and | shipping stuff for all variants, but you will run into limitations, | especially regarding flash size. Fair enough, but only if one runs from NAND. I wouldn't want to be the guy that said hiding the differences between these devices in a single rootfs is in any way going to be easy, but, I think as the number of devices cranks up -- and we can expect it to get quite large even a couple of years out I think -- the multi-rootfs story seems to me it won't stay under control, considering these things are 50+MB and take a while to create and the maintainence angle. In contrast we will definitely need separate kernels per-device whatever we do... it could be quite interesting to try to cope / expose / own all device specific detail in the bootloader + kernel with totally shared rootfs per instruction set, referring to the kernel for any config. - -Andy -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iEYEARECAAYFAkkoQcQACgkQOjLpvpq7dMoV2gCfQ0wpGarqE496hlt56/fwm/hk YIEAn1CJN9Ra/ocmXtK+U2GMag+kZxxm =h45M -----END PGP SIGNATURE----- _______________________________________________ devel mailing list [email protected] https://lists.openmoko.org/mailman/listinfo/devel
