This patch introduces the idea of having a dependency structure for idle-stop. The structure encapsulates the following: 1. Bitmask for version of idle-stop 2. Bitmask for propterties like ENABLE/DISABLE 3. Function pointer which helps handle how the stop must be invoked
This patch lays a foundation for other idle-stop versions to be added and handled cleanly based on their specified requirments. Currently it handles the existing "idle-stop" version by setting the discovery bits and the function pointer. Earlier this patch was posted as part of this series : https://lkml.org/lkml/2020/3/4/589 Signed-off-by: Pratik Rajesh Sampat <psam...@linux.ibm.com> Signed-off-by: Abhishek Goel <hunt...@linux.vnet.ibm.com> --- v1->v2: This patch is newly added in this series. arch/powerpc/include/asm/processor.h | 17 +++++++++++++++++ arch/powerpc/kernel/dt_cpu_ftrs.c | 5 +++++ arch/powerpc/platforms/powernv/idle.c | 18 ++++++++++++++---- drivers/cpuidle/cpuidle-powernv.c | 3 ++- 4 files changed, 38 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index eedcbfb9a6ff..66fa20476d0e 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -429,6 +429,23 @@ extern void power4_idle_nap(void); extern unsigned long cpuidle_disable; enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF}; +#define STOP_ENABLE 0x00000001 + +#define STOP_VERSION_P9 0x1 + +/* + * Classify the dependencies of the stop states + * @idle_stop: function handler to handle the quirk stop version + * @cpuidle_prop: Signify support for stop states through kernel and/or firmware + * @stop_version: Classify quirk versions for stop states + */ +typedef struct { + unsigned long (*idle_stop)(unsigned long psscr, bool mmu_on); + uint8_t cpuidle_prop; + uint8_t stop_version; +} stop_deps_t; +extern stop_deps_t stop_dep; + extern int powersave_nap; /* set if nap mode can be used in idle loop */ extern void power7_idle_type(unsigned long type); diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index 182b4047c1ef..db1a525e090d 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -292,6 +292,8 @@ static int __init feat_enable_idle_stop(struct dt_cpu_feature *f) lpcr |= LPCR_PECE1; lpcr |= LPCR_PECE2; mtspr(SPRN_LPCR, lpcr); + stop_dep.cpuidle_prop |= STOP_ENABLE; + stop_dep.stop_version = STOP_VERSION_P9; return 1; } @@ -657,6 +659,9 @@ static void __init cpufeatures_setup_start(u32 isa) } } +stop_deps_t stop_dep = {NULL, 0x0, 0x0}; +EXPORT_SYMBOL(stop_dep); + static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f) { const struct dt_cpu_feature_match *m; diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c index 1841027b25c5..538f0842ac3f 100644 --- a/arch/powerpc/platforms/powernv/idle.c +++ b/arch/powerpc/platforms/powernv/idle.c @@ -842,7 +842,7 @@ static unsigned long power9_offline_stop(unsigned long psscr) #ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE __ppc64_runlatch_off(); - srr1 = power9_idle_stop(psscr, true); + srr1 = stop_dep.idle_stop(psscr, true); __ppc64_runlatch_on(); #else /* @@ -858,7 +858,7 @@ static unsigned long power9_offline_stop(unsigned long psscr) local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE; __ppc64_runlatch_off(); - srr1 = power9_idle_stop(psscr, false); + srr1 = stop_dep.idle_stop(psscr, true); __ppc64_runlatch_on(); local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_KERNEL; @@ -886,7 +886,7 @@ void power9_idle_type(unsigned long stop_psscr_val, psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val; __ppc64_runlatch_off(); - srr1 = power9_idle_stop(psscr, true); + srr1 = stop_dep.idle_stop(psscr, true); __ppc64_runlatch_on(); fini_irq_for_idle_irqsoff(); @@ -1390,8 +1390,18 @@ static int __init pnv_init_idle_states(void) nr_pnv_idle_states = 0; supported_cpuidle_states = 0; - if (cpuidle_disable != IDLE_NO_OVERRIDE) + if (cpuidle_disable != IDLE_NO_OVERRIDE || + !(stop_dep.cpuidle_prop & STOP_ENABLE)) goto out; + + /* Check for supported version in kernel */ + if (stop_dep.stop_version & STOP_VERSION_P9) { + stop_dep.idle_stop = power9_idle_stop; + } else { + stop_dep.idle_stop = NULL; + goto out; + } + rc = pnv_parse_cpuidle_dt(); if (rc) return rc; diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 1b299e801f74..7430a8edf5c9 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -371,7 +371,8 @@ static int powernv_add_idle_states(void) */ static int powernv_idle_probe(void) { - if (cpuidle_disable != IDLE_NO_OVERRIDE) + if (cpuidle_disable != IDLE_NO_OVERRIDE || + !(stop_dep.cpuidle_prop & STOP_ENABLE)) return -ENODEV; if (firmware_has_feature(FW_FEATURE_OPAL)) { -- 2.17.1
