diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h index 65d0ffb2aa33..140ddb9ae5a8 100644 --- a/arch/powerpc/include/asm/paca.h +++ b/arch/powerpc/include/asm/paca.h @@ -173,6 +173,11 @@ struct paca_struct { u8 thread_mask; /* Mask to denote subcore sibling threads */ u8 subcore_sibling_mask; + /* + * Pointer to an array which contains pointer + * to the sibling threads' paca. + */ + struct paca_struct **thread_sibling_pacas; #endif #ifdef CONFIG_PPC_BOOK3S_64 diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 795505e27535..e7c8229a8812 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -728,6 +728,7 @@ int main(void) OFFSET(PACA_THREAD_IDLE_STATE, paca_struct, thread_idle_state); OFFSET(PACA_THREAD_MASK, paca_struct, thread_mask); OFFSET(PACA_SUBCORE_SIBLING_MASK, paca_struct, subcore_sibling_mask); + OFFSET(PACA_SIBLING_PACA_PTRS, paca_struct, thread_sibling_pacas); #endif DEFINE(PPC_DBELL_SERVER, PPC_DBELL_SERVER); diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 995728736677..24717a73b6bb 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -375,6 +375,46 @@ _GLOBAL(power9_idle_stop) li r4,1 b pnv_powersave_common /* No return */ + + +/* + * On waking up from stop 0,1,2 with ESL=1 on POWER9 DD1, + * HSPRG0 will be set to the HSPRG0 value of one of the + * threads in this core. Thus the value we have in r13 + * may not be this thread's paca pointer. + * + * Fortunately, the TIR remains invariant. Since this thread's + * paca pointer is recorded in all its sibling's paca, we can + * correctly recover this thread's paca pointer if we + * know the index of this thread in the core. + * + * This index can be obtained from the TIR. + * + * i.e, thread's position in the core = TIR. + * If this value is i, then this thread's paca is + * paca->thread_sibling_pacas[i]. + */ +power9_dd1_recover_paca: + mfspr r4, SPRN_TIR + /* + * Since each entry in thread_sibling_pacas is 8 bytes + * we need to left-shift by 3 bits. Thus r4 = i * 8 + */ + sldi r4, r4, 3 + /* Get &paca->thread_sibling_pacas[0] in r5 */ + ld r5, PACA_SIBLING_PACA_PTRS(r13) + /* Load paca->thread_sibling_pacas[i] into r13 */ + ldx r13, r4, r5 + SET_PACA(r13) + ld r2, PACATOC(r13) + /* + * Indicate that we have lost NVGPR state + * which needs to be restored from the stack. + */ + li r3, 1 + stb r0,PACA_NAPSTATELOST(r13) + blr + /* * Called from reset vector. Check whether we have woken up with * hypervisor state loss. If yes, restore hypervisor state and return @@ -385,7 +425,13 @@ _GLOBAL(power9_idle_stop) */ _GLOBAL(pnv_restore_hyp_resource) BEGIN_FTR_SECTION - ld r2,PACATOC(r13); +BEGIN_FTR_SECTION_NESTED(70) + mflr r6 + bl power9_dd1_recover_paca + mtlr r6 +FTR_SECTION_ELSE_NESTED(70) + ld r2, PACATOC(r13) +ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_POWER9_DD1, 70) /* * POWER ISA 3. Use PSSCR to determine if we * are waking up from deep idle state diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c index 63ade787aec4..b369e39aa392 100644 --- a/arch/powerpc/platforms/powernv/idle.c +++ b/arch/powerpc/platforms/powernv/idle.c @@ -122,9 +122,12 @@ static void pnv_alloc_idle_core_states(void) for (i = 0; i < nr_cores; i++) { int first_cpu = i * threads_per_core; int node = cpu_to_node(first_cpu); + size_t paca_ptr_array_size; core_idle_state = kmalloc_node(sizeof(u32), GFP_KERNEL, node); *core_idle_state = PNV_CORE_IDLE_THREAD_BITS; + paca_ptr_array_size = (threads_per_core * + sizeof(struct paca_struct *)); for (j = 0; j < threads_per_core; j++) { int cpu = first_cpu + j; @@ -132,6 +135,11 @@ static void pnv_alloc_idle_core_states(void) paca[cpu].core_idle_state_ptr = core_idle_state; paca[cpu].thread_idle_state = PNV_THREAD_RUNNING; paca[cpu].thread_mask = 1 << j; + if (!cpu_has_feature(CPU_FTR_POWER9_DD1)) + continue; + paca[cpu].thread_sibling_pacas = + kmalloc_node(paca_ptr_array_size, + GFP_KERNEL, node); } } @@ -560,6 +568,28 @@ static int __init pnv_init_idle_states(void) pnv_alloc_idle_core_states(); + /* + * For each CPU, record its PACA address in each of it's + * sibling thread's PACA at the slot corresponding to this + * CPU's index in the core. + */ + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) { + int cpu; + + pr_info("powernv: idle: Saving PACA pointers of all CPUs in their thread sibling PACA\n"); + for_each_possible_cpu(cpu) { + int base_cpu = cpu_first_thread_sibling(cpu); + int idx = cpu_thread_in_core(cpu); + int i; + + for (i = 0; i < threads_per_core; i++) { + int j = base_cpu + i; + + paca[j].thread_sibling_pacas[idx] = &paca[cpu]; + } + } + } + if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED) ppc_md.power_save = power7_idle;