From: "Gautham R. Shenoy" <ego@xxxxxxxxxxxxxxxxxx> Currently all the low-power idle states are expected to wake up at reset vector 0x100. Which is why the macro IDLE_STATE_ENTER_SEQ that puts the CPU to an idle state and never returns. On ISA_300, when the ESL and EC bits in the PSSCR are zero, the CPU is expected to wake up at the next instruction of the idle instruction. This patch adds a new macro named IDLE_STATE_ENTER_SEQ_NORET for the no-return variant and reuses the name IDLE_STATE_ENTER_SEQ for a variant that allows resuming operation at the instruction next to the idle-instruction. Signed-off-by: Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/cpuidle.h | 5 ++++- arch/powerpc/kernel/exceptions-64s.S | 6 +++--- arch/powerpc/kernel/idle_book3s.S | 10 +++++----- 3 files changed, 12 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/include/asm/cpuidle.h b/arch/powerpc/include/asm/cpuidle.h index 3919332..0a3255b 100644 --- a/arch/powerpc/include/asm/cpuidle.h +++ b/arch/powerpc/include/asm/cpuidle.h @@ -21,7 +21,7 @@ /* Idle state entry routines */ #ifdef CONFIG_PPC_P7_NAP -#define IDLE_STATE_ENTER_SEQ(IDLE_INST) \ +#define IDLE_STATE_ENTER_SEQ(IDLE_INST) \ /* Magic NAP/SLEEP/WINKLE mode enter sequence */ \ std r0,0(r1); \ ptesync; \ @@ -29,6 +29,9 @@ 1: cmpd cr0,r0,r0; \ bne 1b; \ IDLE_INST; \ + +#define IDLE_STATE_ENTER_SEQ_NORET(IDLE_INST) \ + IDLE_STATE_ENTER_SEQ(IDLE_INST) \ b . #endif /* CONFIG_PPC_P7_NAP */ diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 1ba82ea..7aa8afc 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -381,12 +381,12 @@ EXC_COMMON_BEGIN(machine_check_handle_early) lbz r3,PACA_THREAD_IDLE_STATE(r13) cmpwi r3,PNV_THREAD_NAP bgt 10f - IDLE_STATE_ENTER_SEQ(PPC_NAP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_NAP) /* No return */ 10: cmpwi r3,PNV_THREAD_SLEEP bgt 2f - IDLE_STATE_ENTER_SEQ(PPC_SLEEP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_SLEEP) /* No return */ 2: @@ -400,7 +400,7 @@ EXC_COMMON_BEGIN(machine_check_handle_early) */ ori r13,r13,1 SET_PACA(r13) - IDLE_STATE_ENTER_SEQ(PPC_WINKLE) + IDLE_STATE_ENTER_SEQ_NORET(PPC_WINKLE) /* No return */ 4: #endif diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 72dac0b..be90e2f 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -205,7 +205,7 @@ pnv_enter_arch207_idle_mode: stb r3,PACA_THREAD_IDLE_STATE(r13) cmpwi cr3,r3,PNV_THREAD_SLEEP bge cr3,2f - IDLE_STATE_ENTER_SEQ(PPC_NAP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_NAP) /* No return */ 2: /* Sleep or winkle */ @@ -239,7 +239,7 @@ pnv_fastsleep_workaround_at_entry: common_enter: /* common code for all the threads entering sleep or winkle */ bgt cr3,enter_winkle - IDLE_STATE_ENTER_SEQ(PPC_SLEEP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_SLEEP) fastsleep_workaround_at_entry: ori r15,r15,PNV_CORE_IDLE_LOCK_BIT @@ -261,7 +261,7 @@ fastsleep_workaround_at_entry: enter_winkle: bl save_sprs_to_stack - IDLE_STATE_ENTER_SEQ(PPC_WINKLE) + IDLE_STATE_ENTER_SEQ_NORET(PPC_WINKLE) /* * r3 - requested stop state @@ -280,7 +280,7 @@ power_enter_stop: ld r4,ADDROFF(pnv_first_deep_stop_state)(r5) cmpd r3,r4 bge 2f - IDLE_STATE_ENTER_SEQ(PPC_STOP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_STOP) 2: /* * Entering deep idle state. @@ -302,7 +302,7 @@ lwarx_loop_stop: bl save_sprs_to_stack - IDLE_STATE_ENTER_SEQ(PPC_STOP) + IDLE_STATE_ENTER_SEQ_NORET(PPC_STOP) _GLOBAL(power7_idle) /* Now check if user or arch enabled NAP mode */ -- 1.9.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html