diff options
| -rw-r--r-- | core/cpu.c | 93 | ||||
| -rw-r--r-- | core/init.c | 10 | ||||
| -rw-r--r-- | include/cpu.h | 4 |
3 files changed, 106 insertions, 1 deletions
@@ -28,6 +28,7 @@ #include <affinity.h> #include <chip.h> #include <timebase.h> +#include <interrupts.h> #include <ccan/str/str.h> #include <ccan/container_of/container_of.h> @@ -49,6 +50,7 @@ static struct lock reinit_lock = LOCK_UNLOCKED; static bool hile_supported; static unsigned long hid0_hile; static unsigned long hid0_attn; +static bool pm_enabled; unsigned long cpu_secondary_start __force_data = 0; @@ -79,6 +81,17 @@ unsigned long __attrconst cpu_stack_top(unsigned int pir) NORMAL_STACK_SIZE - STACK_TOP_GAP; } +static void cpu_wake(struct cpu_thread *cpu) +{ + /* Is it idle ? If not, no need to wake */ + sync(); + if (!cpu->in_idle) + return; + + /* Poke IPI */ + icp_kick_cpu(cpu); +} + static struct cpu_thread *cpu_find_job_target(void) { struct cpu_thread *cpu, *best, *me = this_cpu(); @@ -194,6 +207,8 @@ struct cpu_job *__cpu_queue_job(struct cpu_thread *cpu, cpu->job_has_no_return = true; else cpu->job_count++; + if (pm_enabled) + cpu_wake(cpu); unlock(&cpu->job_lock); return job; @@ -279,9 +294,87 @@ static void cpu_idle_default(enum cpu_wake_cause wake_on __unused) cpu_relax(); } +static void cpu_idle_p8(enum cpu_wake_cause wake_on) +{ + uint64_t lpcr = mfspr(SPR_LPCR) & ~SPR_LPCR_P8_PECE; + struct cpu_thread *cpu = this_cpu(); + + if (!pm_enabled) { + cpu_idle_default(wake_on); + return; + } + + /* If we are waking on job, whack DEC to highest value */ + if (wake_on == cpu_wake_on_job) + mtspr(SPR_DEC, 0x7fffffff); + + /* Clean up ICP, be ready for IPIs */ + icp_prep_for_pm(); + + /* Setup wakup cause in LPCR */ + lpcr |= SPR_LPCR_P8_PECE2 | SPR_LPCR_P8_PECE3; + mtspr(SPR_LPCR, lpcr); + + /* Synchronize with wakers */ + if (wake_on == cpu_wake_on_job) { + /* Mark ourselves in idle so other CPUs know to send an IPI */ + cpu->in_idle = true; + sync(); + + /* Check for jobs again */ + if (cpu_check_jobs(cpu) || !pm_enabled) + goto skip_sleep; + } else { + /* Mark outselves sleeping so cpu_set_pm_enable knows to + * send an IPI + */ + cpu->in_sleep = true; + sync(); + + /* Check if PM got disabled */ + if (!pm_enabled) + goto skip_sleep; + } + + /* Enter nap */ + enter_pm_state(false); + +skip_sleep: + /* Restore */ + sync(); + cpu->in_idle = false; + cpu->in_sleep = false; + reset_cpu_icp(); +} + +void cpu_set_pm_enable(bool enabled) +{ + struct cpu_thread *cpu; + + prlog(PR_INFO, "CPU: %sing power management\n", + enabled ? "enabl" : "disabl"); + + pm_enabled = enabled; + + if (enabled) + return; + + /* If disabling, take everybody out of PM */ + sync(); + for_each_available_cpu(cpu) { + while (cpu->in_sleep || cpu->in_idle) { + icp_kick_cpu(cpu); + cpu_relax(); + } + } +} + void cpu_idle(enum cpu_wake_cause wake_on) { switch(proc_gen) { + case proc_gen_p8: + cpu_idle_p8(wake_on); + break; default: cpu_idle_default(wake_on); break; diff --git a/core/init.c b/core/init.c index e977125..d32eea6 100644 --- a/core/init.c +++ b/core/init.c @@ -360,8 +360,10 @@ static bool load_kernel(void) * If the kernel is at 0, restore it as it was overwritten * by our vectors. */ - if (kernel_entry < 0x2000) + if (kernel_entry < 0x2000) { + cpu_set_pm_enable(false); memcpy(NULL, old_vectors, 0x2000); + } } else { if (!kernel_size) printf("INIT: Assuming kernel at %p\n", @@ -478,6 +480,9 @@ void __noreturn load_and_boot_kernel(bool is_reboot) mem_dump_free(); + /* Take processours out of nap */ + cpu_set_pm_enable(false); + printf("INIT: Starting kernel at 0x%llx, fdt at %p (size 0x%x)\n", kernel_entry, fdt, fdt_totalsize(fdt)); @@ -771,6 +776,9 @@ void __noreturn __nomcount main_cpu_entry(const void *fdt, u32 master_cpu) */ setup_reset_vector(); + /* We can now do NAP mode */ + cpu_set_pm_enable(true); + /* * Sycnhronize time bases. Thi resets all the TB values to a small * value (so they appear to go backward at this point), and synchronize diff --git a/include/cpu.h b/include/cpu.h index 4164151..341e73d 100644 --- a/include/cpu.h +++ b/include/cpu.h @@ -66,6 +66,8 @@ struct cpu_thread { bool in_mcount; bool in_poller; bool in_reinit; + bool in_sleep; + bool in_idle; uint32_t hbrt_spec_wakeup; /* primary only */ uint64_t save_l2_fir_action1; uint64_t current_token; @@ -251,6 +253,8 @@ extern void cpu_process_jobs(void); extern void cpu_process_local_jobs(void); /* Check if there's any job pending */ bool cpu_check_jobs(struct cpu_thread *cpu); +/* Enable/disable PM */ +void cpu_set_pm_enable(bool pm_enabled); static inline void cpu_give_self_os(void) { |