/* * arch/i386/kernel/acpi/cstate.c * * Copyright (C) 2005 Intel Corporation * Venkatesh Pallipadi * - Added _PDC for SMP C-states on Intel CPUs */ #include #include #include #include #include #include /* * Initialize bm_flags based on the CPU cache properties * On SMP it depends on cache configuration * - When cache is not shared among all CPUs, we flush cache * before entering C3. * - When cache is shared among all CPUs, we use bm_check * mechanism as in UP case * * This routine is called only after all the CPUs are online */ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags, unsigned int cpu) { struct cpuinfo_x86 *c = cpu_data + cpu; flags->bm_check = 0; if (num_online_cpus() == 1) flags->bm_check = 1; else if (c->x86_vendor == X86_VENDOR_INTEL) { /* * Today all CPUs that support C3 share cache. * TBD: This needs to look at cache shared map, once * multi-core detection patch makes to the base. */ flags->bm_check = 1; } } EXPORT_SYMBOL(acpi_processor_power_init_bm_check);