From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Date: Sun, 24 Feb 2013 18:24:16 +0100 Subject: [Buildroot] editing device_table_dev.txt In-Reply-To: <5125F7BB.50403@petroprogram.com> References: <1361403460.22521.44.camel@genx.eng.msli.com> <5125F38B.2030204@petroprogram.com> <5125F50C.7020902@petroprogram.com> <20130221102315.GB12155@sapphire.tkos.co.il> <5125F7BB.50403@petroprogram.com> Message-ID: <20130224182416.64b51c7b@skate> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Dear Stefan Fr?berg, On Thu, 21 Feb 2013 12:32:27 +0200, Stefan Fr?berg wrote: > >>> Also kernel .config file should also have CONFIG_DEVTMPFS and > >>> DEVTMPFS as 'y'. > >> Sorry, that should have been CONFIG_DEVTMPFS=y and > >> CONFIG_DEVTMPFS_MOUNT=y > > Kernel version 2.6.30 is too old for that. > > > > baruch > > > > It is ? > Damn, then the only options are mdev and udev. No, because our mdev/udev handling makes the assumption that devtmpfs support is enabled in the kernel. Contrary to what Arnout says, I don't think devtmpfs support is *mandatory* to get mdev to work. But in Buildroot, we've decided to support only mdev on top of devtmpfs. >From linux/linux.mk: $(if $(BR2_ROOTFS_DEVICE_CREATION_STATIC),, $(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS,$(@D)/.config) $(call KCONFIG_ENABLE_OPT,CONFIG_DEVTMPFS_MOUNT,$(@D)/.config)) So whenever we're not using the "static" method, we enable DEVTMPFS + DEVTMPFS_MOUNT. So if you're using a kernel < 2.6.32 (I think that's the kernel release in which devtmpfs was introduced), then your only choice is to use the static method. Obviously, another better solution is to upgrade the kernel version you're using. The .config posted by John Stile originally mentions a board/atmel/at91sam9g20ek/ directory, which seems to indicate John is using the AT91SAM9G20 SoC. This SoC is perfectly well supported by mainline kernel versions, so there should normally be no reason to stick with the old 2.6.30. Best regards, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com