/* * This is the old power_save() function from idle.c: * * Written by Cort Dougan (cort@cs.nmt.edu) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * */ #include #include #include void power_save(void) { /* * Make sure the CPU has the DOZE or NAP feature set. * We assume that chip-specific initialization code * has set any other registers necessary (e.g. HID0). */ if (!(cur_cpu_spec[smp_processor_id()]->cpu_features & (CPU_FTR_CAN_DOZE | CPU_FTR_CAN_NAP))) return; /* * Disable interrupts to prevent a lost wakeup * when going to sleep. This is necessary even with * RTLinux since we are not guaranteed an interrupt * didn't come in and is waiting for a __sti() before * emulating one. This way, we really do hard disable. * * We assume that we're sti-ed when we come in here. We * are in the idle loop so if we're cli-ed then it's a bug * anyway. * -- Cort */ _nmask_and_or_msr(MSR_EE, 0); if (!current->need_resched) { /* set the POW bit in the MSR, and enable interrupts * so we wake up sometime! */ _nmask_and_or_msr(0, MSR_POW | MSR_EE); } _nmask_and_or_msr(0, MSR_EE); }