On Fri, Dec 14, 2018 at 10:09:23AM +0530, Viresh Kumar wrote: > On 13-12-18, 18:01, Russell King wrote: > > diff --git a/arch/arm/mach-spear/generic.h b/arch/arm/mach-spear/generic.h > > index 909b97c0b237..815333fc320c 100644 > > --- a/arch/arm/mach-spear/generic.h > > +++ b/arch/arm/mach-spear/generic.h > > @@ -20,6 +20,8 @@ > > > > #include <asm/mach/time.h> > > > > +extern volatile int prima2_pen_release; > > prima2 ? > > I haven't tried but this may cause build regressions as well, I am > surprised on how this passed for you. Thanks. These patches aren't all build tested - I don't see the point of wasting hours build testing when these platforms /really/ need something better. This is not supposed to be a finished patch, but a patch to get folk to do something about this issue. Please fix this issue properly. I can't give you a patch to do that, you need to sort it yourself, but failure to do anything _will_ result in an updated version of this patch being merged. > > extern void spear13xx_timer_init(void); > > extern void spear3xx_timer_init(void); > > extern struct pl022_ssp_controller pl022_plat_data; > > diff --git a/arch/arm/mach-spear/headsmp.S b/arch/arm/mach-spear/headsmp.S > > index c52192dc3d9f..6e250b6c0aa2 100644 > > --- a/arch/arm/mach-spear/headsmp.S > > +++ b/arch/arm/mach-spear/headsmp.S > > @@ -43,5 +43,5 @@ pen: ldr r7, [r6] > > > > .align > > 1: .long . > > - .long pen_release > > + .long spear_pen_release > > ENDPROC(spear13xx_secondary_startup) > > diff --git a/arch/arm/mach-spear/hotplug.c b/arch/arm/mach-spear/hotplug.c > > index 12edd1cf8a12..0dd84f609627 100644 > > --- a/arch/arm/mach-spear/hotplug.c > > +++ b/arch/arm/mach-spear/hotplug.c > > @@ -16,6 +16,8 @@ > > #include <asm/cp15.h> > > #include <asm/smp_plat.h> > > > > +#include "generic.h" > > + > > static inline void cpu_enter_lowpower(void) > > { > > unsigned int v; > > @@ -57,7 +59,7 @@ static inline void spear13xx_do_lowpower(unsigned int cpu, int *spurious) > > for (;;) { > > wfi(); > > > > - if (pen_release == cpu) { > > + if (spear_pen_release == cpu) { > > /* > > * OK, proper wakeup, we're done > > */ > > diff --git a/arch/arm/mach-spear/platsmp.c b/arch/arm/mach-spear/platsmp.c > > index 39038a03836a..b1ff4bb86f6d 100644 > > --- a/arch/arm/mach-spear/platsmp.c > > +++ b/arch/arm/mach-spear/platsmp.c > > @@ -20,16 +20,21 @@ > > #include <mach/spear.h> > > #include "generic.h" > > > > +/* XXX spear_pen_release is cargo culted code - DO NOT COPY XXX */ > > +volatile int spear_pen_release = -1; > > + > > /* > > - * Write pen_release in a way that is guaranteed to be visible to all > > - * observers, irrespective of whether they're taking part in coherency > > + * XXX CARGO CULTED CODE - DO NOT COPY XXX > > + * > > + * Write spear_pen_release in a way that is guaranteed to be visible to > > + * all observers, irrespective of whether they're taking part in coherency > > * or not. This is necessary for the hotplug code to work reliably. > > */ > > -static void write_pen_release(int val) > > +static void spear_write_pen_release(int val) > > { > > - pen_release = val; > > + spear_pen_release = val; > > smp_wmb(); > > - sync_cache_w(&pen_release); > > + sync_cache_w(&spear_pen_release); > > } > > > > static DEFINE_SPINLOCK(boot_lock); > > @@ -42,7 +47,7 @@ static void spear13xx_secondary_init(unsigned int cpu) > > * let the primary processor know we're out of the > > * pen, then head off into the C entry point > > */ > > - write_pen_release(-1); > > + spear_write_pen_release(-1); > > > > /* > > * Synchronise with the boot thread. > > @@ -64,17 +69,17 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) > > /* > > * The secondary processor is waiting to be released from > > * the holding pen - release it, then wait for it to flag > > - * that it has been released by resetting pen_release. > > + * that it has been released by resetting spear_pen_release. > > * > > - * Note that "pen_release" is the hardware CPU ID, whereas > > + * Note that "spear_pen_release" is the hardware CPU ID, whereas > > * "cpu" is Linux's internal ID. > > */ > > - write_pen_release(cpu); > > + spear_write_pen_release(cpu); > > > > timeout = jiffies + (1 * HZ); > > while (time_before(jiffies, timeout)) { > > smp_rmb(); > > - if (pen_release == -1) > > + if (spear_pen_release == -1) > > break; > > > > udelay(10); > > @@ -86,7 +91,7 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) > > */ > > spin_unlock(&boot_lock); > > > > - return pen_release != -1 ? -ENOSYS : 0; > > + return spear_pen_release != -1 ? -ENOSYS : 0; > > } > > > > /* > > -- > > 2.7.4 > > -- > viresh > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up