[PATCH v7 11/11] powerpc/powernv: Use deepest stop state when cpu is offlined

From: Shreyas B. Prabhu
Date: Thu Jul 07 2016 - 16:48:43 EST


If hardware supports stop state, use the deepest stop state when
the cpu is offlined.

Reviewed-by: Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Shreyas B. Prabhu <shreyas@xxxxxxxxxxxxxxxxxx>
---
- No changes since v1
arch/powerpc/platforms/powernv/idle.c | 15 +++++++++++++--
arch/powerpc/platforms/powernv/powernv.h | 1 +
arch/powerpc/platforms/powernv/smp.c | 4 +++-
3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c
index 006e467..2f6968c 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -253,6 +253,11 @@ static void power9_idle(void)
u64 pnv_first_deep_stop_state;

/*
+ * Deepest stop idle state. Used when a cpu is offlined
+ */
+u64 pnv_deepest_stop_state;
+
+/*
* Power ISA 3.0 idle initialization.
*
* POWER ISA 3.0 defines a new SPR Processor stop Status and Control
@@ -314,8 +319,11 @@ static int __init pnv_arch300_idle_init(struct device_node *np, u32 *flags,
}

/*
- * Set pnv_first_deep_stop_state to the first stop level
- * to cause hypervisor state loss
+ * Set pnv_first_deep_stop_state and pnv_deepest_stop_state.
+ * pnv_first_deep_stop_state should be set to the first stop
+ * level to cause hypervisor state loss.
+ * pnv_deepest_stop_state should be set to the deepest stop
+ * stop state.
*/
pnv_first_deep_stop_state = MAX_STOP_STATE;
for (i = 0; i < dt_idle_states; i++) {
@@ -324,6 +332,9 @@ static int __init pnv_arch300_idle_init(struct device_node *np, u32 *flags,
if ((flags[i] & OPAL_PM_LOSE_FULL_CONTEXT) &&
(pnv_first_deep_stop_state > psscr_rl))
pnv_first_deep_stop_state = psscr_rl;
+
+ if (pnv_deepest_stop_state < psscr_rl)
+ pnv_deepest_stop_state = psscr_rl;
}

out:
diff --git a/arch/powerpc/platforms/powernv/powernv.h b/arch/powerpc/platforms/powernv/powernv.h
index 6dbc0a1..da7c843 100644
--- a/arch/powerpc/platforms/powernv/powernv.h
+++ b/arch/powerpc/platforms/powernv/powernv.h
@@ -18,6 +18,7 @@ static inline void pnv_pci_shutdown(void) { }
#endif

extern u32 pnv_get_supported_cpuidle_states(void);
+extern u64 pnv_deepest_stop_state;

extern void pnv_lpc_init(void);

diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index ad7b1a3..c789258 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -182,7 +182,9 @@ static void pnv_smp_cpu_kill_self(void)

ppc64_runlatch_off();

- if (idle_states & OPAL_PM_WINKLE_ENABLED)
+ if (cpu_has_feature(CPU_FTR_ARCH_300))
+ srr1 = power9_idle_stop(pnv_deepest_stop_state);
+ else if (idle_states & OPAL_PM_WINKLE_ENABLED)
srr1 = power7_winkle();
else if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
(idle_states & OPAL_PM_SLEEP_ENABLED_ER1))
--
2.4.11