Commit 33093e18 authored by Venki Pallipadi's avatar Venki Pallipadi Committed by Len Brown
Browse files

i7300_idle: Cleanup based review comments 



Cleanup of i7300 idle driver based on review comments from Randy Dunlap,
Andi Kleen and Len Brown.

Signed-off-by: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 3ad0b02e

drivers/idle/Kconfig

+6 −5
Original line number Diff line number Diff line
@@ -5,12 +5,13 @@ config I7300_IDLE_IOAT_CHANNEL 
	bool



config I7300_IDLE

	tristate "Intel chipset idle power saving driver"

	tristate "Intel chipset idle memory power saving driver"

	select I7300_IDLE_IOAT_CHANNEL

	depends on X86_64

	depends on X86_64 && EXPERIMENTAL

	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.

	  Enable memory power savings when idle 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/i7300_idle.c

+18 −15
Original line number Diff line number Diff line
@@ -35,6 +35,8 @@ 
#define I7300_IDLE_DRIVER_VERSION	"1.55"

#define I7300_PRINT			"i7300_idle:"



#define MAX_STOP_RETRIES	10



static int debug;

module_param_named(debug, debug, uint, 0644);

MODULE_PARM_DESC(debug, "Enable debug printks in this driver");
@@ -47,12 +49,12 @@ MODULE_PARM_DESC(debug, "Enable debug printks in this driver"); 
 *  0 = No throttling

 *  1 = Throttle when > 4 activations per eval window (Maximum throttling)

 *  2 = Throttle when > 8 activations

 *  168 = Throttle when > 168 activations (Minimum throttling)

 *  168 = Throttle when > 672 activations (Minimum throttling)

 */

#define MAX_THRTLWLIMIT		168

static uint i7300_idle_thrtlowlm = 1;

module_param_named(thrtlwlimit, i7300_idle_thrtlowlm, uint, 0644);

MODULE_PARM_DESC(thrtlwlimit,

#define MAX_THROTTLE_LOW_LIMIT		168

static uint throttle_low_limit = 1;

module_param_named(throttle_low_limit, throttle_low_limit, uint, 0644);

MODULE_PARM_DESC(throttle_low_limit,

		"Value for THRTLOWLM activation field "

		"(0 = disable throttle, 1 = Max throttle, 168 = Min throttle)");
@@ -111,9 +113,9 @@ static int i7300_idle_ioat_start(void) 
static void i7300_idle_ioat_stop(void)

{

	int i;

	u8 sts;

	u64 sts;



	for (i = 0; i < 5; i++) {

	for (i = 0; i < MAX_STOP_RETRIES; i++) {

		writeb(IOAT_CHANCMD_RESET,

			ioat_chanbase + IOAT1_CHANCMD_OFFSET);
@@ -127,9 +129,10 @@ static void i7300_idle_ioat_stop(void) 


	}



	if (i == 5)

		dprintk("failed to suspend+reset I/O AT after 5 retries\n");



	if (i == MAX_STOP_RETRIES) {

		dprintk("failed to stop I/O AT after %d retries\n",

			MAX_STOP_RETRIES);

	}

}



/* Test I/O AT by copying 1024 byte from 2k to 1k */
@@ -276,7 +279,7 @@ static void __exit i7300_idle_ioat_exit(void) 
	i7300_idle_ioat_stop();



	/* Wait for a while for the channel to halt before releasing */

	for (i = 0; i < 10; i++) {

	for (i = 0; i < MAX_STOP_RETRIES; i++) {

		writeb(IOAT_CHANCMD_RESET,

		       ioat_chanbase + IOAT1_CHANCMD_OFFSET);
@@ -390,9 +393,9 @@ static void i7300_idle_start(void) 
	new_ctl = i7300_idle_thrtctl_saved & ~DIMM_THRTCTL_THRMHUNT;

	pci_write_config_byte(fbd_dev, DIMM_THRTCTL, new_ctl);



	limit = i7300_idle_thrtlowlm;

	if (unlikely(limit > MAX_THRTLWLIMIT))

		limit = MAX_THRTLWLIMIT;

	limit = throttle_low_limit;

	if (unlikely(limit > MAX_THROTTLE_LOW_LIMIT))

		limit = MAX_THROTTLE_LOW_LIMIT;



	pci_write_config_byte(fbd_dev, DIMM_THRTLOW, limit);
@@ -441,7 +444,7 @@ static int i7300_idle_notifier(struct notifier_block *nb, unsigned long val, 
	static ktime_t idle_begin_time;

	static int time_init = 1;



	if (!i7300_idle_thrtlowlm)

	if (!throttle_low_limit)

		return 0;



	if (unlikely(time_init)) {