diff options
| -rw-r--r-- | drivers/thermal/intel/intel_hfi.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/thermal/intel/intel_hfi.c b/drivers/thermal/intel/intel_hfi.c index 713da8befd40..22445403b520 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> @@ -367,6 +368,32 @@ static void hfi_set_hw_table(struct hfi_instance *hfi_instance) 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 @@ -420,6 +447,10 @@ void intel_hfi_online(unsigned int cpu) /* * 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); @@ -488,6 +519,10 @@ 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); } |