diff options
Diffstat (limited to 'arch/powerpc/kernel/entry_64.S')
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 44c733f4f829..9ae8451bbc83 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -448,6 +448,19 @@ END_FTR_SECTION_IFSET(CPU_FTR_DSCR) std r23,_CCR(r1) std r1,KSP(r3) /* Set old stack pointer */ +#ifdef CONFIG_PPC_BOOK3S_64 +BEGIN_FTR_SECTION + /* + * Back up the TAR across context switches. Note that the TAR is not + * available for use in the kernel. (To provide this, the TAR should + * be backed up/restored on exception entry/exit instead, and be in + * pt_regs. FIXME, this should be in pt_regs anyway (for debug).) + */ + mfspr r0,SPRN_TAR + std r0,THREAD_TAR(r3) +END_FTR_SECTION_IFSET(CPU_FTR_BCTAR) +#endif + #ifdef CONFIG_SMP /* We need a sync somewhere here to make sure that if the * previous task gets rescheduled on another CPU, it sees all @@ -530,6 +543,13 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT) mr r1,r8 /* start using new stack pointer */ std r7,PACAKSAVE(r13) +#ifdef CONFIG_PPC_BOOK3S_64 +BEGIN_FTR_SECTION + ld r0,THREAD_TAR(r4) + mtspr SPRN_TAR,r0 +END_FTR_SECTION_IFSET(CPU_FTR_BCTAR) +#endif + #ifdef CONFIG_ALTIVEC BEGIN_FTR_SECTION ld r0,THREAD_VRSAVE(r4) |