[PATCH] ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372

[PATCH] ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rjw@sisk.pl>

Instead of coding the undocumented dependencies between power domains
A3RV and A4LC on SH7372 directly into the low-level power up/down
routines, make A3RV be a subdomain of A4LC, which will cause the
same dependecies to hold.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---

This patch hasn't been tested yet, so caveat emptor!

Thanks,
Rafael

---
 arch/arm/mach-shmobile/pm-sh7372.c    |   43 +---------------------------------
 arch/arm/mach-shmobile/setup-sh7372.c |    3 ++
 2 files changed, 5 insertions(+), 41 deletions(-)

Index: linux-2.6/arch/arm/mach-shmobile/pm-sh7372.c
=================================--- linux-2.6.orig/arch/arm/mach-shmobile/pm-sh7372.c
+++ linux-2.6/arch/arm/mach-shmobile/pm-sh7372.c
@@ -91,36 +91,6 @@ static int pd_power_up(struct generic_pm
 	return ret;
 }
 
-static int pd_power_up_a3rv(struct generic_pm_domain *genpd)
-{
-	int ret = pd_power_up(genpd);
-
-	/* force A4LC on after A3RV has been requested on */
-	pm_genpd_poweron(&sh7372_a4lc.genpd);
-
-	return ret;
-}
-
-static int pd_power_down_a3rv(struct generic_pm_domain *genpd)
-{
-	int ret = pd_power_down(genpd);
-
-	/* try to power down A4LC after A3RV is requested off */
-	pm_genpd_poweron(&sh7372_a4lc.genpd);
-	queue_work(pm_wq, &sh7372_a4lc.genpd.power_off_work);
-
-	return ret;
-}
-
-static int pd_power_down_a4lc(struct generic_pm_domain *genpd)
-{
-	/* only power down A4LC if A3RV is off */
-	if (!(__raw_readl(PSTR) & (1 << sh7372_a3rv.bit_shift)))
-		return pd_power_down(genpd);
-
-	return 0;
-}
-
 static bool pd_active_wakeup(struct device *dev)
 {
 	return true;
@@ -134,17 +104,8 @@ void sh7372_init_pm_domain(struct sh7372
 	genpd->stop_device = pm_clk_suspend;
 	genpd->start_device = pm_clk_resume;
 	genpd->active_wakeup = pd_active_wakeup;
-
-	if (sh7372_pd = &sh7372_a4lc) {
-		genpd->power_off = pd_power_down_a4lc;
-		genpd->power_on = pd_power_up;
-	} else if (sh7372_pd = &sh7372_a3rv) {
-		genpd->power_off = pd_power_down_a3rv;
-		genpd->power_on = pd_power_up_a3rv;
-	} else {
-		genpd->power_off = pd_power_down;
-		genpd->power_on = pd_power_up;
-	}
+	genpd->power_off = pd_power_down;
+	genpd->power_on = pd_power_up;
 	genpd->power_on(&sh7372_pd->genpd);
 }
 
Index: linux-2.6/arch/arm/mach-shmobile/setup-sh7372.c
=================================--- linux-2.6.orig/arch/arm/mach-shmobile/setup-sh7372.c
+++ linux-2.6/arch/arm/mach-shmobile/setup-sh7372.c
@@ -30,6 +30,7 @@
 #include <linux/sh_dma.h>
 #include <linux/sh_intc.h>
 #include <linux/sh_timer.h>
+#include <linux/pm_domain.h>
 #include <mach/hardware.h>
 #include <mach/sh7372.h>
 #include <asm/mach-types.h>
@@ -848,6 +849,8 @@ void __init sh7372_add_standard_devices(
 	sh7372_init_pm_domain(&sh7372_a3ri);
 	sh7372_init_pm_domain(&sh7372_a3sg);
 
+	pm_genpd_add_subdomain(&sh7372_a4lc.genpd, &sh7372_a3sg.genpd);
+
 	platform_add_devices(sh7372_early_devices,
 			    ARRAY_SIZE(sh7372_early_devices));
 

Re: [PATCH] ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372

[Magnus Damm]

On Wed, Jul 13, 2011 at 7:40 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
>
> Instead of coding the undocumented dependencies between power domains
> A3RV and A4LC on SH7372 directly into the low-level power up/down
> routines, make A3RV be a subdomain of A4LC, which will cause the
> same dependecies to hold.
>
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> ---

Thanks for your effort of cleaning up the code!

You are correct that putting A3RV as a subdomain of A4LC will help
with one side of the problem. The not so visible problem at this point
is the connection between A4R and A3RV. A4R is a power domain which
contains some I/O devices and the two power domains A3RV and A3RI.

Because of the hardware dependency between A4R and A3RV we would need
to force A4R to be powered on whenever A3RV is being used. So A4R is
the "real" parent pm domain from the data sheet point of view.

To simplify the software side one option could be to make A4LC the
parent of A3RV and A4R the parent of A4LC. This is not however a very
good fit either - the hardware allows us to have A4LC powered on
without A4R or A3RV. This case is quite common and happens when any
LCD panel is enabled but the rest of the system is idle.

For the case when no A4R support is in place your suggestion is fine.
But to support A4R we need to deal with something similar to what my
patch does anyway. It is worth nothing that A4R contains an interrupt
controller and needs special care that way too. Also the I/O devices
in A4R require QoS software to be in place before we can start
powering down A4R for real.

So the reason behind my somewhat ugly existing A3RV and A4LC power
domain code is to make sure the framework code can do whatever we need
to do for A4R support. Or perhaps it can be done in a better way? Any
ideas?

Thanks,

/ magnus

Re: [PATCH] ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372

[Magnus Damm]

On Wed, Jul 13, 2011 at 7:40 AM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
>
> Instead of coding the undocumented dependencies between power domains
> A3RV and A4LC on SH7372 directly into the low-level power up/down
> routines, make A3RV be a subdomain of A4LC, which will cause the
> same dependecies to hold.
>
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> ---

Thanks for your effort of cleaning up the code!

You are correct that putting A3RV as a subdomain of A4LC will help
with one side of the problem. The not so visible problem at this point
is the connection between A4R and A3RV. A4R is a power domain which
contains some I/O devices and the two power domains A3RV and A3RI.

Because of the hardware dependency between A4R and A3RV we would need
to force A4R to be powered on whenever A3RV is being used. So A4R is
the "real" parent pm domain from the data sheet point of view.

To simplify the software side one option could be to make A4LC the
parent of A3RV and A4R the parent of A4LC. This is not however a very
good fit either - the hardware allows us to have A4LC powered on
without A4R or A3RV. This case is quite common and happens when any
LCD panel is enabled but the rest of the system is idle.

For the case when no A4R support is in place your suggestion is fine.
But to support A4R we need to deal with something similar to what my
patch does anyway. It is worth nothing that A4R contains an interrupt
controller and needs special care that way too. Also the I/O devices
in A4R require QoS software to be in place before we can start
powering down A4R for real.

So the reason behind my somewhat ugly existing A3RV and A4LC power
domain code is to make sure the framework code can do whatever we need
to do for A4R support. Or perhaps it can be done in a better way? Any
ideas?

Thanks,

/ magnus

[PATCH] ARM / shmobile: Make A3RV be a subdomain of A4LC on SH7372

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rjw@sisk.pl>

Instead of coding the undocumented dependencies between power domains
A3RV and A4LC on SH7372 directly into the low-level power up/down
routines, make A3RV be a subdomain of A4LC, which will cause the
same dependecies to hold.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---

This patch hasn't been tested yet, so caveat emptor!

Thanks,
Rafael

---
 arch/arm/mach-shmobile/pm-sh7372.c    |   43 +---------------------------------
 arch/arm/mach-shmobile/setup-sh7372.c |    3 ++
 2 files changed, 5 insertions(+), 41 deletions(-)

Index: linux-2.6/arch/arm/mach-shmobile/pm-sh7372.c
===================================================================
--- linux-2.6.orig/arch/arm/mach-shmobile/pm-sh7372.c
+++ linux-2.6/arch/arm/mach-shmobile/pm-sh7372.c
@@ -91,36 +91,6 @@ static int pd_power_up(struct generic_pm
 	return ret;
 }
 
-static int pd_power_up_a3rv(struct generic_pm_domain *genpd)
-{
-	int ret = pd_power_up(genpd);
-
-	/* force A4LC on after A3RV has been requested on */
-	pm_genpd_poweron(&sh7372_a4lc.genpd);
-
-	return ret;
-}
-
-static int pd_power_down_a3rv(struct generic_pm_domain *genpd)
-{
-	int ret = pd_power_down(genpd);
-
-	/* try to power down A4LC after A3RV is requested off */
-	pm_genpd_poweron(&sh7372_a4lc.genpd);
-	queue_work(pm_wq, &sh7372_a4lc.genpd.power_off_work);
-
-	return ret;
-}
-
-static int pd_power_down_a4lc(struct generic_pm_domain *genpd)
-{
-	/* only power down A4LC if A3RV is off */
-	if (!(__raw_readl(PSTR) & (1 << sh7372_a3rv.bit_shift)))
-		return pd_power_down(genpd);
-
-	return 0;
-}
-
 static bool pd_active_wakeup(struct device *dev)
 {
 	return true;
@@ -134,17 +104,8 @@ void sh7372_init_pm_domain(struct sh7372
 	genpd->stop_device = pm_clk_suspend;
 	genpd->start_device = pm_clk_resume;
 	genpd->active_wakeup = pd_active_wakeup;
-
-	if (sh7372_pd == &sh7372_a4lc) {
-		genpd->power_off = pd_power_down_a4lc;
-		genpd->power_on = pd_power_up;
-	} else if (sh7372_pd == &sh7372_a3rv) {
-		genpd->power_off = pd_power_down_a3rv;
-		genpd->power_on = pd_power_up_a3rv;
-	} else {
-		genpd->power_off = pd_power_down;
-		genpd->power_on = pd_power_up;
-	}
+	genpd->power_off = pd_power_down;
+	genpd->power_on = pd_power_up;
 	genpd->power_on(&sh7372_pd->genpd);
 }
 
Index: linux-2.6/arch/arm/mach-shmobile/setup-sh7372.c
===================================================================
--- linux-2.6.orig/arch/arm/mach-shmobile/setup-sh7372.c
+++ linux-2.6/arch/arm/mach-shmobile/setup-sh7372.c
@@ -30,6 +30,7 @@
 #include <linux/sh_dma.h>
 #include <linux/sh_intc.h>
 #include <linux/sh_timer.h>
+#include <linux/pm_domain.h>
 #include <mach/hardware.h>
 #include <mach/sh7372.h>
 #include <asm/mach-types.h>
@@ -848,6 +849,8 @@ void __init sh7372_add_standard_devices(
 	sh7372_init_pm_domain(&sh7372_a3ri);
 	sh7372_init_pm_domain(&sh7372_a3sg);
 
+	pm_genpd_add_subdomain(&sh7372_a4lc.genpd, &sh7372_a3sg.genpd);
+
 	platform_add_devices(sh7372_early_devices,
 			    ARRAY_SIZE(sh7372_early_devices));