diff options
| -rw-r--r-- | arch/arc/kernel/mcip.c | 18 | ||||
| -rw-r--r-- | arch/arc/kernel/smp.c | 46 |
2 files changed, 21 insertions, 43 deletions
diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c index e48a1331c588..e18d36eb0af6 100644 --- a/arch/arc/kernel/mcip.c +++ b/arch/arc/kernel/mcip.c @@ -97,26 +97,8 @@ static void mcip_ipi_clear(int irq) #endif } -volatile int wake_flag; - -static void mcip_wakeup_cpu(int cpu, unsigned long pc) -{ - BUG_ON(cpu == 0); - wake_flag = cpu; -} - -void arc_platform_smp_wait_to_boot(int cpu) -{ - while (wake_flag != cpu) - ; - - wake_flag = 0; - __asm__ __volatile__("j @first_lines_of_secondary \n"); -} - struct plat_smp_ops plat_smp_ops = { .info = smp_cpuinfo_buf, - .cpu_kick = mcip_wakeup_cpu, .ipi_send = mcip_ipi_send, .ipi_clear = mcip_ipi_clear, }; diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c index be13d12420ba..f6175fc5f2bb 100644 --- a/arch/arc/kernel/smp.c +++ b/arch/arc/kernel/smp.c @@ -72,35 +72,29 @@ void __init smp_cpus_done(unsigned int max_cpus) } /* - * After power-up, a non Master CPU needs to wait for Master to kick start it - * - * The default implementation halts - * - * This relies on platform specific support allowing Master to directly set - * this CPU's PC (to be @first_lines_of_secondary() and kick start it. - * - * In lack of such h/w assist, platforms can override this function - * - make this function busy-spin on a token, eventually set by Master - * (from arc_platform_smp_wakeup_cpu()) - * - Once token is available, jump to @first_lines_of_secondary - * (using inline asm). - * - * Alert: can NOT use stack here as it has not been determined/setup for CPU. - * If it turns out to be elaborate, it's better to code it in assembly - * + * Default smp boot helper for Run-on-reset case where all cores start off + * together. Non-masters need to wait for Master to start running. + * This is implemented using a flag in memory, which Non-masters spin-wait on. + * Master sets it to cpu-id of core to "ungate" it. */ -void __weak arc_platform_smp_wait_to_boot(int cpu) +static volatile int wake_flag; + +static void arc_default_smp_cpu_kick(int cpu, unsigned long pc) { - /* - * As a hack for debugging - since debugger will single-step over the - * FLAG insn - wrap the halt itself it in a self loop - */ - __asm__ __volatile__( - "1: \n" - " flag 1 \n" - " b 1b \n"); + BUG_ON(cpu == 0); + wake_flag = cpu; +} + +void arc_platform_smp_wait_to_boot(int cpu) +{ + while (wake_flag != cpu) + ; + + wake_flag = 0; + __asm__ __volatile__("j @first_lines_of_secondary \n"); } + const char *arc_platform_smp_cpuinfo(void) { return plat_smp_ops.info ? : ""; @@ -161,6 +155,8 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) if (plat_smp_ops.cpu_kick) plat_smp_ops.cpu_kick(cpu, (unsigned long)first_lines_of_secondary); + else + arc_default_smp_cpu_kick(cpu, (unsigned long)NULL); /* wait for 1 sec after kicking the secondary */ wait_till = jiffies + HZ; |