powerpc/mm: any thread in one core can be the first to setup TLB1

On e6500, in the case of cpu hotplug, either thread in one core
may be the first thread initilzing the TLB1. The subsequent threads
must not setup it again.

The code is derived from the comment of Scott Wood.

Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Scott Wood <oss@buserror.net>
This commit is contained in:
chenhui zhao 2015-12-24 08:39:57 +08:00 committed by Scott Wood
parent d64716caf7
commit ebb9d30a6a
2 changed files with 9 additions and 3 deletions

View File

@ -94,6 +94,14 @@ static inline int cpu_last_thread_sibling(int cpu)
return cpu | (threads_per_core - 1); return cpu | (threads_per_core - 1);
} }
static inline u32 get_tensr(void)
{
#ifdef CONFIG_BOOKE
if (cpu_has_feature(CPU_FTR_SMT))
return mfspr(SPRN_TENSR);
#endif
return 1;
}
#endif /* _ASM_POWERPC_CPUTHREADS_H */ #endif /* _ASM_POWERPC_CPUTHREADS_H */

View File

@ -640,9 +640,7 @@ static void early_init_this_mmu(void)
* transient mapping would cause problems. * transient mapping would cause problems.
*/ */
#ifdef CONFIG_SMP #ifdef CONFIG_SMP
if (cpu != boot_cpuid && if (hweight32(get_tensr()) > 1)
(cpu != cpu_first_thread_sibling(cpu) ||
cpu == cpu_first_thread_sibling(boot_cpuid)))
map = false; map = false;
#endif #endif