i7300_idle driver v1.55

The Intel 7300 Memory Controller supports dynamic throttling of memory which can
be used to save power when system is idle. This driver does the memory
throttling when all CPUs are idle on such a system.

Refer to "Intel 7300 Memory Controller Hub (MCH)" datasheet
for the config space description.
Signed-off-by: Andy Henroid <andrew.d.henroid@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>

MAINTAINERS

@@ -2078,6 +2078,12 @@ L:	linux-ide@vger.kernel.org
 L:	linux-scsi@vger.kernel.org
 S:	Orphan
 
+IDLE-I7300
+P:	Andy Henroid
+M:	andrew.d.henroid@intel.com
+L:	linux-pm@lists.linux-foundation.org
+S:	Supported
+
 IEEE 1394 SUBSYSTEM (drivers/ieee1394)
 P:	Ben Collins
 M:	ben.collins@ubuntu.com

arch/x86/Kconfig

@@ -1536,6 +1536,8 @@ source "arch/x86/kernel/cpu/cpufreq/Kconfig"
 
 source "drivers/cpuidle/Kconfig"
 
+source "drivers/idle/Kconfig"
+
 endmenu
 
 

drivers/Makefile

@@ -82,6 +82,7 @@ obj-$(CONFIG_EISA)		+= eisa/
 obj-y				+= lguest/
 obj-$(CONFIG_CPU_FREQ)		+= cpufreq/
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle/
+obj-y				+= idle/
 obj-$(CONFIG_MMC)		+= mmc/
 obj-$(CONFIG_MEMSTICK)		+= memstick/
 obj-$(CONFIG_NEW_LEDS)		+= leds/

drivers/dma/ioat_dma.c

@@ -171,6 +171,9 @@ static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
 	xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
 	xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
 
+#if CONFIG_I7300_IDLE_IOAT_CHANNEL
+	device->common.chancnt--;
+#endif
 	for (i = 0; i < device->common.chancnt; i++) {
 		ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
 		if (!ioat_chan) {

drivers/idle/Kconfig

+
+menu "Memory power savings"
+
+config I7300_IDLE_IOAT_CHANNEL
+	bool
+
+config I7300_IDLE
+	tristate "Intel chipset idle power saving driver"
+	select I7300_IDLE_IOAT_CHANNEL
+	depends on X86_64
+	help
+	  Enable idle power savings with certain Intel server chipsets.
+	  The chipset must have I/O AT support, such as the Intel 7300.
+	  The power savings depends on the type and quantity of DRAM devices.
+
+endmenu

drivers/idle/Makefile

+obj-$(CONFIG_I7300_IDLE)			+= i7300_idle.o
+

include/asm-x86/idle.h

@@ -6,6 +6,7 @@
 
 struct notifier_block;
 void idle_notifier_register(struct notifier_block *n);
+void idle_notifier_unregister(struct notifier_block *n);
 
 void enter_idle(void);
 void exit_idle(void);

include/linux/pci_ids.h

@@ -2422,6 +2422,7 @@
 #define PCI_DEVICE_ID_INTEL_MCH_PC1	0x359a
 #define PCI_DEVICE_ID_INTEL_E7525_MCH	0x359e
 #define PCI_DEVICE_ID_INTEL_IOAT_CNB	0x360b
+#define PCI_DEVICE_ID_INTEL_FBD_CNB	0x360c
 #define PCI_DEVICE_ID_INTEL_ICH10_0	0x3a14
 #define PCI_DEVICE_ID_INTEL_ICH10_1	0x3a16
 #define PCI_DEVICE_ID_INTEL_ICH10_2	0x3a18