On Mon, Apr 20, 2015 at 04:49:13PM +0100, Russell King - ARM Linux wrote: > Guys, > > If you're going to introduce a dependency on some infrastructure which > you absolutely require for booting, then _please_ ensure that the > configuration system is updated such that pre-existing kernel > configurations continue to work. > > Don't leave it such that the infrastructure ends up returning -ENOSYS, > which then filters down into your SoC specific code, and aborts the > initialisation of critical infrastructure, leaving you with a totally > silent boot failure. > > In this case, it's the addition of syscon to OMAP internals, > specifically in omap_control_init(). > > This is explicitly targetted at OMAP people, who have wasted much of > my day today investigating why their platforms no longer boot in DT > mode. Let's be clear about how this needs to be fixed: 1. OMAP must select MFD_SYSCON in its Kconfig when DT is enabled, since OMAP silently fails to boot when this symbol is not enabled. 2. omap_clk_init() really needs to have some diagnostic printk()s in it to indicate when something like omap_control_init() fails. 3. omap_clk_init() probably should _not_ return immediately when one of the children (such as omap_control_init) fails to initialise, as omitting the clocks pretty much ensures that the kernel will BUG() a few moments later in the timer code. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html