diff options
| -rw-r--r-- | drivers/thermal/intel/intel_hfi.c | 119 |
1 files changed, 93 insertions, 26 deletions
diff --git a/drivers/thermal/intel/intel_hfi.c b/drivers/thermal/intel/intel_hfi.c index c69db6c90869..3b04c6ec4fca 100644 --- a/drivers/thermal/intel/intel_hfi.c +++ b/drivers/thermal/intel/intel_hfi.c @@ -24,6 +24,7 @@ #include <linux/bitops.h> #include <linux/cpufeature.h> #include <linux/cpumask.h> +#include <linux/delay.h> #include <linux/gfp.h> #include <linux/io.h> #include <linux/kernel.h> @@ -34,7 +35,9 @@ #include <linux/processor.h> #include <linux/slab.h> #include <linux/spinlock.h> +#include <linux/suspend.h> #include <linux/string.h> +#include <linux/syscore_ops.h> #include <linux/topology.h> #include <linux/workqueue.h> @@ -347,6 +350,52 @@ static void init_hfi_instance(struct hfi_instance *hfi_instance) hfi_instance->data = hfi_instance->hdr + hfi_features.hdr_size; } +/* Caller must hold hfi_instance_lock. */ +static void hfi_enable(void) +{ + u64 msr_val; + + rdmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); + msr_val |= HW_FEEDBACK_CONFIG_HFI_ENABLE_BIT; + wrmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); +} + +static void hfi_set_hw_table(struct hfi_instance *hfi_instance) +{ + phys_addr_t hw_table_pa; + u64 msr_val; + + hw_table_pa = virt_to_phys(hfi_instance->hw_table); + msr_val = hw_table_pa | HW_FEEDBACK_PTR_VALID_BIT; + wrmsrl(MSR_IA32_HW_FEEDBACK_PTR, msr_val); +} + +/* Caller must hold hfi_instance_lock. */ +static void hfi_disable(void) +{ + u64 msr_val; + int i; + + rdmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); + msr_val &= ~HW_FEEDBACK_CONFIG_HFI_ENABLE_BIT; + wrmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); + + /* + * Wait for hardware to acknowledge the disabling of HFI. Some + * processors may not do it. Wait for ~2ms. This is a reasonable + * time for hardware to complete any pending actions on the HFI + * memory. + */ + for (i = 0; i < 2000; i++) { + rdmsrl(MSR_IA32_PACKAGE_THERM_STATUS, msr_val); + if (msr_val & PACKAGE_THERM_STATUS_HFI_UPDATED) + break; + + udelay(1); + cpu_relax(); + } +} + /** * intel_hfi_online() - Enable HFI on @cpu * @cpu: CPU in which the HFI will be enabled @@ -364,8 +413,6 @@ void intel_hfi_online(unsigned int cpu) { struct hfi_instance *hfi_instance; struct hfi_cpu_info *info; - phys_addr_t hw_table_pa; - u64 msr_val; u16 die_id; /* Nothing to do if hfi_instances are missing. */ @@ -392,25 +439,26 @@ void intel_hfi_online(unsigned int cpu) /* * Now check if the HFI instance of the package/die of @cpu has been * initialized (by checking its header). In such case, all we have to - * do is to add @cpu to this instance's cpumask. + * do is to add @cpu to this instance's cpumask and enable the instance + * if needed. */ mutex_lock(&hfi_instance_lock); - if (hfi_instance->hdr) { - cpumask_set_cpu(cpu, hfi_instance->cpus); - goto unlock; - } + if (hfi_instance->hdr) + goto enable; /* * Hardware is programmed with the physical address of the first page * frame of the table. Hence, the allocated memory must be page-aligned. + * + * Some processors do not forget the initial address of the HFI table + * even after having been reprogrammed. Keep using the same pages. Do + * not free them. */ hfi_instance->hw_table = alloc_pages_exact(hfi_features.nr_table_pages, GFP_KERNEL | __GFP_ZERO); if (!hfi_instance->hw_table) goto unlock; - hw_table_pa = virt_to_phys(hfi_instance->hw_table); - /* * Allocate memory to keep a local copy of the table that * hardware generates. @@ -420,31 +468,20 @@ void intel_hfi_online(unsigned int cpu) if (!hfi_instance->local_table) goto free_hw_table; - /* - * Program the address of the feedback table of this die/package. On - * some processors, hardware remembers the old address of the HFI table - * even after having been reprogrammed and re-enabled. Thus, do not free - * the pages allocated for the table or reprogram the hardware with a - * new base address. Namely, program the hardware only once. - */ - msr_val = hw_table_pa | HW_FEEDBACK_PTR_VALID_BIT; - wrmsrl(MSR_IA32_HW_FEEDBACK_PTR, msr_val); - init_hfi_instance(hfi_instance); INIT_DELAYED_WORK(&hfi_instance->update_work, hfi_update_work_fn); raw_spin_lock_init(&hfi_instance->table_lock); raw_spin_lock_init(&hfi_instance->event_lock); +enable: cpumask_set_cpu(cpu, hfi_instance->cpus); - /* - * Enable the hardware feedback interface and never disable it. See - * comment on programming the address of the table. - */ - rdmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); - msr_val |= HW_FEEDBACK_CONFIG_HFI_ENABLE_BIT; - wrmsrl(MSR_IA32_HW_FEEDBACK_CONFIG, msr_val); + /* Enable this HFI instance if this is its first online CPU. */ + if (cpumask_weight(hfi_instance->cpus) == 1) { + hfi_set_hw_table(hfi_instance); + hfi_enable(); + } unlock: mutex_unlock(&hfi_instance_lock); @@ -484,6 +521,10 @@ void intel_hfi_offline(unsigned int cpu) mutex_lock(&hfi_instance_lock); cpumask_clear_cpu(cpu, hfi_instance->cpus); + + if (!cpumask_weight(hfi_instance->cpus)) + hfi_disable(); + mutex_unlock(&hfi_instance_lock); } @@ -532,6 +573,30 @@ static __init int hfi_parse_features(void) return 0; } +static void hfi_do_enable(void) +{ + /* This code runs only on the boot CPU. */ + struct hfi_cpu_info *info = &per_cpu(hfi_cpu_info, 0); + struct hfi_instance *hfi_instance = info->hfi_instance; + + /* No locking needed. There is no concurrency with CPU online. */ + hfi_set_hw_table(hfi_instance); + hfi_enable(); +} + +static int hfi_do_disable(void) +{ + /* No locking needed. There is no concurrency with CPU offline. */ + hfi_disable(); + + return 0; +} + +static struct syscore_ops hfi_pm_ops = { + .resume = hfi_do_enable, + .suspend = hfi_do_disable, +}; + void __init intel_hfi_init(void) { struct hfi_instance *hfi_instance; @@ -563,6 +628,8 @@ void __init intel_hfi_init(void) if (!hfi_updates_wq) goto err_nomem; + register_syscore_ops(&hfi_pm_ops); + return; err_nomem: |