dynamicpower-devel

[Dynamicpower-devel] DPM fixups for CONFIG_PM=n

[Todd P. <tp...@mv...>]

Now that DPM extensions for driver scale callbacks and device
constraints do not depend on LDM PM data structures, some support for
these can be provided when CONFIG_PM=n (although that is expected to be
a rare situation).  A patch to fixup these follows, thanks -- Todd

diff -u linux-2.6.10/drivers/base/power/Makefile linux-2.6.10/drivers/base/power/Makefile
--- linux-2.6.10/drivers/base/power/Makefile	2005-03-10 21:26:07.000000000 +0000
+++ linux-2.6.10/drivers/base/power/Makefile	2005-03-21 23:02:11.000000000 +0000
@@ -1,5 +1,5 @@
-obj-y			:= shutdown.o
-obj-$(CONFIG_PM)	+= main.o suspend.o resume.o runtime.o sysfs.o power-dpm.o
+obj-y			:= shutdown.o power-dpm.o
+obj-$(CONFIG_PM)	+= main.o suspend.o resume.o runtime.o sysfs.o
 
 ifeq ($(CONFIG_DEBUG_DRIVER),y)
 EXTRA_CFLAGS += -DDEBUG
diff -u linux-2.6.10/drivers/base/power/power-dpm.c linux-2.6.10/drivers/base/power/power-dpm.c
--- linux-2.6.10/drivers/base/power/power-dpm.c	2005-03-10 21:30:56.000000000 +0000
+++ linux-2.6.10/drivers/base/power/power-dpm.c	2005-03-21 23:24:13.000000000 +0000
@@ -155,13 +155,12 @@
  * Device constraints
  */
 
-
+#ifdef CONFIG_DPM
 LIST_HEAD(dpm_constraints);
 DECLARE_MUTEX(dpm_constraints_sem);
 
 void assert_constraints(struct constraints *constraints)
 {
-#ifdef CONFIG_DPM
 	if (! constraints || constraints->asserted)
 		return;
 
@@ -172,13 +171,11 @@
 
 	/* DPM-PM-TODO: Check against DPM state. */
 
-#endif /* CONFIG_DPM */
 }
 
 
 void deassert_constraints(struct constraints *constraints)
 {
-#ifdef CONFIG_DPM
 	if (! constraints || ! constraints->asserted)
 		return;
 
@@ -186,7 +183,6 @@
 	constraints->asserted = 0;
 	list_del_init(&constraints->entry);
 	up(&dpm_constraints_sem);
-#endif /* CONFIG_DPM */
 }
 
 
@@ -196,7 +192,6 @@
 static ssize_t 
 constraints_show(struct device * dev, char * buf)
 {
-#ifdef CONFIG_DPM
 	int i, cnt = 0;
 	
 	if (dev->constraints) {
@@ -215,15 +210,11 @@
 	}
 
 	return cnt;
-#else /* CONFIG_DPM */
-	return 0;
-#endif /* CONFIG_DPM */
 }
 
 static ssize_t
 constraints_store(struct device * dev, const char * buf, size_t count)
 {
-#ifdef CONFIG_DPM
 	int num_args, paramid, min, max;
 	int cidx;
 	const char *cp, *paramname;
@@ -299,14 +290,21 @@
 	}
 
 	return ret < 0 ? ret : count;
-#else /* CONFIG_DPM */
-	return -EINVAL;
-#endif /* CONFIG_DPM */
 }
 
 DEVICE_ATTR(constraints,S_IWUSR | S_IRUGO,
             constraints_show,constraints_store);
 
+#else /* CONFIG_DPM */
+void assert_constraints(struct constraints *constraints)
+{
+}
+
+void deassert_constraints(struct constraints *constraints)
+{
+}
+#endif /* CONFIG_DPM */
+
 #ifdef CONFIG_DPM
 
 /*
@@ -410,6 +408,7 @@
 
 int dpm_show_opconstraints(struct dpm_opt *opt, char * buf)
 {
+#ifdef CONFIG_PM
 	struct list_head * entry;
 	int len = 0;
 
@@ -423,6 +422,9 @@
 	}
 
 	return len;
+#else /* CONFIG_PM */
+	return 0;
+#endif /* CONFIG_PM */
 }
 #endif /* CONFIG_DPM */
 
diff -u linux-2.6.10/include/linux/pm.h linux-2.6.10/include/linux/pm.h
--- linux-2.6.10/include/linux/pm.h	2005-03-10 21:26:07.000000000 +0000
+++ linux-2.6.10/include/linux/pm.h	2005-03-21 23:08:21.000000000 +0000
@@ -260,17 +260,10 @@
 	SCALE_POSTCHANGE,
 };
 
-#ifdef CONFIG_PM
 extern void assert_constraints(struct constraints *);
 extern void deassert_constraints(struct constraints *);
 extern void power_event(char *eventstr);
 extern void device_power_event(struct device * dev, char *eventstr);
-#else /* CONFIG_PM */
-static inline void assert_constraints(struct constraints *c) {}
-static inline void deassert_constraints(struct constraints *c) {}
-static inline void power_event(char *eventstr) {}
-static inline void device_power_event(struct device * dev, char *eventstr) {}
-#endif /* CONFIG_PM */
 
 #endif /* __KERNEL__ */
 

[Dynamicpower-devel] DPM questions

[Daniel P. <d.p...@gm...>]

Hi all,

I've been researching the DPM for omap platform. In my tests I
switched the policies created in the dpm-setup-omap1510 script and
could realize the frequency switching. I also created some lower
frequency OPs - big power savings :-)
In my group, I was assigned to make more tests and understand DPM deeply.
I have some doubts and appreciate very much if someone can help.

-How can I assign an user process to a operating state (task-4,
task-3...task, task+3, task+4)? Reading /proc/driver/dpm/stats I see
that the system only switches among idle, idle-task and task.  How can
I start a process  in task-4 state for instance?

-Is there any user level application or deamon that runs and manage
the task assignment, a test policy manager already developed?

-Which are the operating points parameters: tc_rate, mpuper_rate and dsp_rate?


Thank very much in advance and best regards,
 

Daniel Petrini
-- 
10LE - Linux
Nokia Institute of Tecnology - INdT
Manaus - Brazil

Re: [Dynamicpower-devel] DPM questions

[Todd P. <tp...@mv...>]

Daniel Petrini wrote:

> -How can I assign an user process to a operating state (task-4,
> task-3...task, task+3, task+4)? Reading /proc/driver/dpm/stats I see
> that the system only switches among idle, idle-task and task.  How can
> I start a process  in task-4 state for instance?

Hi Daniel -- In newer code write a task state name to /proc/<pid>/dpmstate:

# echo -n "task-4" > /proc/$$/dpmstate
# ls
# cat /sys/dpm/state/stats
state: idle-task ticks: 1996910 times: 13591
state: idle ticks: 749169144 times: 13385
state: sleep ticks: 0 times: 0
state: task-4 ticks: 1287414 times: 121
...

Using older patches there's another, now-deprecated, interface for it:

# echo "set_task_state $$ -4" > /proc/driver/dpm/cmd

> -Is there any user level application or deamon that runs and manage
> the task assignment, a test policy manager already developed?

A number of folks have developed application software to manage DPM for 
their consumer product needs or as a developer tool in Linux development 
platform product, not sure specifically whether any features regarding 
task state assignments have been developed, and I don't know that 
anything is available for general use.  If you have ideas on what might 
be needed for managing task assignments I'm open to suggestions.

> -Which are the operating points parameters: tc_rate, mpuper_rate and dsp_rate?

OMAP power parameters "tc-div", "per-div", and "dsp-div" refer to the 
clock divisors that may be set in the ARM CKCTL for these components... 
the rate associated with these would normally refer to a value computed 
in conjunction with settings of other upstream clocks (that are divided 
down per those parameters).

Hope that helps,


-- 
Todd