Dear Sebastian, On Thu, 7 Nov 2013 13:22:35 -0800 Sebastian Hesselbarth <[email protected]> wrote:
> On 11/07/2013 05:20 PM, Arnd Bergmann wrote: > > On Thursday 07 November 2013, Sebastian Hesselbarth wrote: > >> Actually, IIRC smp_twd does not compile without SMP set, so the above > >> should at least be 'HAVE_ARM_TWD if SMP'. If you shrink MULTI_V7 down > >> to non-SMP cores, you can disable it and it will fail to compile. > > > > If there are UP-systems for which TWD is the best clocksource, we should > > probably fix the code to allow that configuration. IIRC there were already > > patches recently in this area, maybe it's already solved. The problems is twd is not mandatory in CA9 UP system, so it may not exist. However, I got answers from soc people, the BG2CD does configured and enabled TWD. so we are lucky and can add HAVE_TWD for BG2CD. > > I just tried barebox bootloader to use TWD as timer on berlin2cd and it > perfectly works, i.e. with time related commands I can see the timer > register decreasing. So the timer is available on this UP SoC. Yep. It is available. > > As said before, compiling linux without CONFIG_SMP but with > CONFIG_HAVE_ARM_TWD gives: > > warning: (SOC_OMAP5 && ARCH_ROCKCHIP && ARCH_SHMOBILE_MULTI && > MACH_BERLIN_BG2 && MACH_BERLIN_BG2CD) selects HAVE_ARM_TWD which has > unmet direct dependencies (SMP) > > and > > arch/arm/kernel/smp_twd.c: In function 'twd_local_timer_of_register': > arch/arm/kernel/smp_twd.c:391: error: 'setup_max_cpus' undeclared (first > use in this function) > arch/arm/kernel/smp_twd.c:391: error: (Each undeclared identifier is > reported only once > arch/arm/kernel/smp_twd.c:391: error: for each function it appears in.) > make[1]: *** [arch/arm/kernel/smp_twd.o] Error 1 > > I haven't looked deeper into this, but I guess it will not be hard > to make ARM_TWD independent of SMP. > > Sebastian > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
