Hi, On Thu, May 23, 2013 at 02:27:37PM +0200, Ralf Baechle wrote: > During the 3.10 merge cycle many MIPS platforms were broken by the > generic idle loop patches. A patch series to fix this has already been > merged but I'm wondering if fb40bc3e94933007d3e42e96daf1ec8044821cb8 > [MIPS: Idle: Re-enable irqs at the end of r3081, au1k and loongson2 > cpu_wait.] is sufficient and correct for Loongson 2. > > In particular: > > o drivers/cpufreq/loongson2_cpufreq.c protects accesses to LOONGSON_CHIPCFG0 > in loongson2_cpu_wait with a spinlock. This spinlock is not used anywhere > else in the kernel so it would appear there is still a race with other > accesses to LOONGSON_CHIPCFG0. > o It's not SMPly correct - even if cpufreq_exit restores the old value of > cpu_wait on a SMP system another processor might still be executing > loongson2_cpu_wait(). I think Loongson2 is UP-only? > o I'd appreciate if at least some basic power saving would be used even if > CONFIG_LOONGSON2_CPUFREQ was disabled, that is loongson2_cpu_wait should > go back to arch/mips/kernel/idle.c. > o Could somebody test if Loongson 2 is working? Thanks! It works (tested d97955625710b57f24427e403f150126078273c2), but cpufreq seems to be broken for some reason: [ 6.136000] calling cpufreq_init+0x0/0x8c @ 1 [ 6.140000] cpufreq: Loongson-2F CPU frequency driver. [ 6.144000] initcall cpufreq_init+0x0/0x8c returned -19 after 4000 usecs I would also like to remind that the boot is still unreliable without this patch: http://patchwork.linux-mips.org/patch/4958/ A.
