Re: [PATCH 3/3] PowerPC/mpc85xx: Add hotplug support on E6500 cores

[Scott Wood <scottwood@freescale.com>]

On Fri, 2015-07-31 at 17:20 +0800, b29983@freescale.com wrote:
> diff --git a/arch/powerpc/platforms/85xx/smp.c 
> b/arch/powerpc/platforms/85xx/smp.c
> index 7f0dadb..8652a49 100644
> --- a/arch/powerpc/platforms/85xx/smp.c
> +++ b/arch/powerpc/platforms/85xx/smp.c
> @@ -189,15 +189,22 @@ static inline u32 read_spin_table_addr_l(void 
> *spin_table)
>  static void wake_hw_thread(void *info)
>  {
>       void fsl_secondary_thread_init(void);
> -     unsigned long imsr1, inia1;
> +     unsigned long imsr, inia;
>       int nr = *(const int *)info;
> -
> -     imsr1 = MSR_KERNEL;
> -     inia1 = *(unsigned long *)fsl_secondary_thread_init;
> -
> -     mttmr(TMRN_IMSR1, imsr1);
> -     mttmr(TMRN_INIA1, inia1);
> -     mtspr(SPRN_TENS, TEN_THREAD(1));
> +     int hw_cpu = get_hard_smp_processor_id(nr);
> +     int thread_idx = cpu_thread_in_core(hw_cpu);
> +
> +     booting_cpu_hwid = (u32)hw_cpu;

Unnecessary cast.  Please explain why you need booting_cpu_hwid.

> +     imsr = MSR_KERNEL;
> +     inia = *(unsigned long *)fsl_secondary_thread_init;
> +     if (thread_idx == 0) {
> +             mttmr(TMRN_IMSR0, imsr);
> +             mttmr(TMRN_INIA0, inia);
> +     } else {
> +             mttmr(TMRN_IMSR1, imsr);
> +             mttmr(TMRN_INIA1, inia);
> +     }
> +     mtspr(SPRN_TENS, TEN_THREAD(thread_idx));

Please rebase this on top of http://patchwork.ozlabs.org/patch/496952/

> +             /*
> +              * If both threads are offline, reset core to start.
> +              * When core is up, Thread 0 always gets up first,
> +              * so bind the current logical cpu with Thread 0.
> +              */
> +             if (hw_cpu != cpu_first_thread_sibling(hw_cpu)) {
> +                     int hw_cpu1, hw_cpu2;
> +
> +                     hw_cpu1 = get_hard_smp_processor_id(primary);
> +                     hw_cpu2 = get_hard_smp_processor_id(primary + 1);
> +                     set_hard_smp_processor_id(primary, hw_cpu2);
> +                     set_hard_smp_processor_id(primary + 1, hw_cpu1);
> +                     /* get new physical cpu id */
> +                     hw_cpu = get_hard_smp_processor_id(nr);

NACK as discussed in http://patchwork.ozlabs.org/patch/454944/

-Scott