From 2671717265ae6e720a9ba5f13fbec3a718983b65 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Mon, 8 Mar 2010 14:07:30 -0500 Subject: intel_idle: native hardware cpuidle driver for latest Intel processors This EXPERIMENTAL driver supersedes acpi_idle on Intel Atom Processors, Intel Core i3/i5/i7 Processors and associated Intel Xeon processors. It does not support the Intel Core2 processor or earlier. For kernels configured with ACPI, CONFIG_INTEL_IDLE=y allows intel_idle to probe before the ACPI processor driver. Booting with "intel_idle.max_cstate=0" disables intel_idle and the system will fall back on ACPI's "acpi_idle". Typical Linux distributions load ACPI processor module early, making CONFIG_INTEL_IDLE=m not easily useful on ACPI platforms. intel_idle probes all processors at module_init time. Processors that are hot-added later will be limited to using C1 in idle. Signed-off-by: Len Brown --- drivers/acpi/processor_driver.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers/acpi/processor_driver.c') diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index deefa8591746..b1034a9ada4e 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -922,9 +922,13 @@ static int __init acpi_processor_init(void) return -ENOMEM; #endif - if (!cpuidle_register_driver(&acpi_idle_driver)) + if (!cpuidle_register_driver(&acpi_idle_driver)) { printk(KERN_DEBUG "ACPI: %s registered with cpuidle\n", acpi_idle_driver.name); + } else { + printk(KERN_DEBUG "ACPI: acpi_idle yielding to %s", + cpuidle_get_driver()->name); + } result = acpi_bus_register_driver(&acpi_processor_driver); if (result < 0) -- cgit v1.2.3-59-g8ed1b