OMAP3 uses full SoC suspend modes as idle states, as such it needs the
whole power-domain and clock-domain code from the idle path.
All that code is not suitable to run with RCU disabled, as such push
RCU-idle deeper still.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/arm/mach-omap2/cpuidle34xx.c | 4 +---
arch/arm/mach-omap2/pm.h | 2 +-
arch/arm/mach-omap2/pm34xx.c | 12 ++++++++++--
3 files changed, 12 insertions(+), 6 deletions(-)
--- a/arch/arm/mach-omap2/cpuidle34xx.c
+++ b/arch/arm/mach-omap2/cpuidle34xx.c
@@ -133,9 +133,7 @@ static int omap3_enter_idle(struct cpuid
}
/* Execute ARM wfi */
- cpuidle_rcu_enter();
- omap_sram_idle();
- cpuidle_rcu_exit();
+ omap_sram_idle(true);
/*
* Call idle CPU PM enter notifier chain to restore
--- a/arch/arm/mach-omap2/pm.h
+++ b/arch/arm/mach-omap2/pm.h
@@ -29,7 +29,7 @@ static inline int omap4_idle_init(void)
extern void *omap3_secure_ram_storage;
extern void omap3_pm_off_mode_enable(int);
-extern void omap_sram_idle(void);
+extern void omap_sram_idle(bool rcuidle);
extern int omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused);
#if defined(CONFIG_PM_OPP)
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -26,6 +26,7 @@
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/of.h>
+#include <linux/cpuidle.h>
#include <trace/events/power.h>
@@ -174,7 +175,7 @@ static int omap34xx_do_sram_idle(unsigne
return 0;
}
-void omap_sram_idle(void)
+void omap_sram_idle(bool rcuidle)
{
/* Variable to tell what needs to be saved and restored
* in omap_sram_idle*/
@@ -254,11 +255,18 @@ void omap_sram_idle(void)
*/
if (save_state)
omap34xx_save_context(omap3_arm_context);
+
+ if (rcuidle)
+ cpuidle_rcu_enter();
+
if (save_state == 1 || save_state == 3)
cpu_suspend(save_state, omap34xx_do_sram_idle);
else
omap34xx_do_sram_idle(save_state);
+ if (rcuidle)
+ rcuidle_rcu_exit();
+
/* Restore normal SDRC POWER settings */
if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
(omap_type() == OMAP2_DEVICE_TYPE_EMU ||
@@ -316,7 +324,7 @@ static int omap3_pm_suspend(void)
omap3_intc_suspend();
- omap_sram_idle();
+ omap_sram_idle(false);
restore:
/* Restore next_pwrsts */On Wed, Jun 08, 2022 at 04:27:57PM +0200, Peter Zijlstra wrote: > @@ -254,11 +255,18 @@ void omap_sram_idle(void) > */ > if (save_state) > omap34xx_save_context(omap3_arm_context); > + > + if (rcuidle) > + cpuidle_rcu_enter(); > + > if (save_state == 1 || save_state == 3) > cpu_suspend(save_state, omap34xx_do_sram_idle); > else > omap34xx_do_sram_idle(save_state); > > + if (rcuidle) > + rcuidle_rcu_exit(); *sigh* so much for this having been exposed to the robots for >2 days :/
* Peter Zijlstra <peterz@infradead.org> [220608 15:00]: > On Wed, Jun 08, 2022 at 04:27:57PM +0200, Peter Zijlstra wrote: > > @@ -254,11 +255,18 @@ void omap_sram_idle(void) > > */ > > if (save_state) > > omap34xx_save_context(omap3_arm_context); > > + > > + if (rcuidle) > > + cpuidle_rcu_enter(); > > + > > if (save_state == 1 || save_state == 3) > > cpu_suspend(save_state, omap34xx_do_sram_idle); > > else > > omap34xx_do_sram_idle(save_state); > > > > + if (rcuidle) > > + rcuidle_rcu_exit(); > > *sigh* so much for this having been exposed to the robots for >2 days :/ I tested your git branch of these patches, so: Reviewed-by: Tony Lindgren <tony@atomide.com> Tested-by: Tony Lindgren <tony@atomide.com>
OMAP4 uses full SoC suspend modes as idle states, as such it needs the
whole power-domain and clock-domain code from the idle path.
All that code is not suitable to run with RCU disabled, as such push
RCU-idle deeper still.
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
Peter here's one more for your series, looks like this is needed to avoid
warnings similar to what you did for omap3.
---
arch/arm/mach-omap2/common.h | 6 ++++--
arch/arm/mach-omap2/cpuidle44xx.c | 8 ++------
arch/arm/mach-omap2/omap-mpuss-lowpower.c | 12 +++++++++++-
arch/arm/mach-omap2/pm44xx.c | 2 +-
4 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -284,11 +284,13 @@ extern u32 omap4_get_cpu1_ns_pa_addr(void);
#if defined(CONFIG_SMP) && defined(CONFIG_PM)
extern int omap4_mpuss_init(void);
-extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state);
+extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
+ bool rcuidle);
extern int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state);
#else
static inline int omap4_enter_lowpower(unsigned int cpu,
- unsigned int power_state)
+ unsigned int power_state,
+ bool rcuidle)
{
cpu_do_idle();
return 0;
diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
--- a/arch/arm/mach-omap2/cpuidle44xx.c
+++ b/arch/arm/mach-omap2/cpuidle44xx.c
@@ -105,9 +105,7 @@ static int omap_enter_idle_smp(struct cpuidle_device *dev,
}
raw_spin_unlock_irqrestore(&mpu_lock, flag);
- cpuidle_rcu_enter();
- omap4_enter_lowpower(dev->cpu, cx->cpu_state);
- cpuidle_rcu_exit();
+ omap4_enter_lowpower(dev->cpu, cx->cpu_state, true);
raw_spin_lock_irqsave(&mpu_lock, flag);
if (cx->mpu_state_vote == num_online_cpus())
@@ -186,10 +184,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev,
}
}
- cpuidle_rcu_enter();
- omap4_enter_lowpower(dev->cpu, cx->cpu_state);
+ omap4_enter_lowpower(dev->cpu, cx->cpu_state, true);
cpu_done[dev->cpu] = true;
- cpuidle_rcu_exit();
/* Wakeup CPU1 only if it is not offlined */
if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -33,6 +33,7 @@
* and first to wake-up when MPUSS low power states are excercised
*/
+#include <linux/cpuidle.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/errno.h>
@@ -214,6 +215,7 @@ static void __init save_l2x0_context(void)
* of OMAP4 MPUSS subsystem
* @cpu : CPU ID
* @power_state: Low power state.
+ * @rcuidle: RCU needs to be idled
*
* MPUSS states for the context save:
* save_state =
@@ -222,7 +224,8 @@ static void __init save_l2x0_context(void)
* 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
* 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
*/
-int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
+int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
+ bool rcuidle)
{
struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET;
@@ -268,6 +271,10 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
cpu_clear_prev_logic_pwrst(cpu);
pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state);
+
+ if (rcuidle)
+ cpuidle_rcu_enter();
+
set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.resume));
omap_pm_ops.scu_prepare(cpu, power_state);
l2x0_pwrst_prepare(cpu, save_state);
@@ -283,6 +290,9 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu)
gic_dist_enable();
+ if (rcuidle)
+ cpuidle_rcu_exit();
+
/*
* Restore the CPUx power state to ON otherwise CPUx
* power domain can transitions to programmed low power
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c
@@ -76,7 +76,7 @@ static int omap4_pm_suspend(void)
* domain CSWR is not supported by hardware.
* More details can be found in OMAP4430 TRM section 4.3.4.2.
*/
- omap4_enter_lowpower(cpu_id, cpu_suspend_state);
+ omap4_enter_lowpower(cpu_id, cpu_suspend_state, false);
/* Restore next powerdomain state */
list_for_each_entry(pwrst, &pwrst_list, node) {
--
2.36.1On Mon, Jun 13, 2022 at 03:39:05PM +0300, Tony Lindgren wrote:
> OMAP4 uses full SoC suspend modes as idle states, as such it needs the
> whole power-domain and clock-domain code from the idle path.
>
> All that code is not suitable to run with RCU disabled, as such push
> RCU-idle deeper still.
>
> Signed-off-by: Tony Lindgren <tony@atomide.com>
> ---
>
> Peter here's one more for your series, looks like this is needed to avoid
> warnings similar to what you did for omap3.
Thanks Tony!
I've had a brief look at omap2_pm_idle() and do I understand it right
that something like the below patch would reduce it to a simple 'WFI'?
What do I do with the rest of that code, because I don't think this
thing has a cpuidle driver to take over, effectively turning it into
dead code.
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -126,10 +126,20 @@ static int omap2_allow_mpu_retention(voi
return 1;
}
-static void omap2_enter_mpu_retention(void)
+static void omap2_do_wfi(void)
{
const int zero = 0;
+ /* WFI */
+ asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
+}
+
+#if 0
+/*
+ * possible cpuidle implementation between WFI and full_retention above
+ */
+static void omap2_enter_mpu_retention(void)
+{
/* The peripherals seem not to be able to wake up the MPU when
* it is in retention mode. */
if (omap2_allow_mpu_retention()) {
@@ -146,8 +157,7 @@ static void omap2_enter_mpu_retention(vo
pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
}
- /* WFI */
- asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
+ omap2_do_wfi();
pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
}
@@ -161,6 +171,7 @@ static int omap2_can_sleep(void)
return 1;
}
+#endif
static void omap2_pm_idle(void)
{
@@ -169,6 +180,7 @@ static void omap2_pm_idle(void)
if (omap_irq_pending())
return;
+#if 0
error = cpu_cluster_pm_enter();
if (error || !omap2_can_sleep()) {
omap2_enter_mpu_retention();
@@ -179,6 +191,9 @@ static void omap2_pm_idle(void)
out_cpu_cluster_pm:
cpu_cluster_pm_exit();
+#else
+ omap2_do_wfi();
+#endif
}
static void __init prcm_setup_regs(void)
Hi,
Adding Aaro Koskinen and Peter Vasil for pm24xx for n800 and n810 related
idle.
* Peter Zijlstra <peterz@infradead.org> [220614 22:07]:
> On Mon, Jun 13, 2022 at 03:39:05PM +0300, Tony Lindgren wrote:
> > OMAP4 uses full SoC suspend modes as idle states, as such it needs the
> > whole power-domain and clock-domain code from the idle path.
> >
> > All that code is not suitable to run with RCU disabled, as such push
> > RCU-idle deeper still.
> >
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > ---
> >
> > Peter here's one more for your series, looks like this is needed to avoid
> > warnings similar to what you did for omap3.
>
> Thanks Tony!
>
> I've had a brief look at omap2_pm_idle() and do I understand it right
> that something like the below patch would reduce it to a simple 'WFI'?
Yes that should do for omap2_do_wfi().
> What do I do with the rest of that code, because I don't think this
> thing has a cpuidle driver to take over, effectively turning it into
> dead code.
As we are establishing a policy where deeper idle states must be
handled by cpuidle, and for most part that has been the case for at least
10 years, I'd just drop the unused functions with an explanation in the
patch why we're doing it. Or the functions could be tagged with
__maybe_unused if folks prefer that.
In the pm24xx case we are not really causing a regression for users as
there are still pending patches to make n800 and n810 truly usable with
the mainline kernel. At least the PMIC and LCD related patches need some
work [0]. The deeper idle states can be added back later using cpuidle
as needed so we have a clear path.
Aaro & Peter V, do you have any better suggestions here as this will
mostly affect you guys currently?
Regards,
Tony
[0] https://lore.kernel.org/linux-omap/20211224214512.1583430-1-peter.vasil@gmail.com/
> --- a/arch/arm/mach-omap2/pm24xx.c
> +++ b/arch/arm/mach-omap2/pm24xx.c
> @@ -126,10 +126,20 @@ static int omap2_allow_mpu_retention(voi
> return 1;
> }
>
> -static void omap2_enter_mpu_retention(void)
> +static void omap2_do_wfi(void)
> {
> const int zero = 0;
>
> + /* WFI */
> + asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
> +}
> +
> +#if 0
> +/*
> + * possible cpuidle implementation between WFI and full_retention above
> + */
> +static void omap2_enter_mpu_retention(void)
> +{
> /* The peripherals seem not to be able to wake up the MPU when
> * it is in retention mode. */
> if (omap2_allow_mpu_retention()) {
> @@ -146,8 +157,7 @@ static void omap2_enter_mpu_retention(vo
> pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
> }
>
> - /* WFI */
> - asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
> + omap2_do_wfi();
>
> pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
> }
> @@ -161,6 +171,7 @@ static int omap2_can_sleep(void)
>
> return 1;
> }
> +#endif
>
> static void omap2_pm_idle(void)
> {
> @@ -169,6 +180,7 @@ static void omap2_pm_idle(void)
> if (omap_irq_pending())
> return;
>
> +#if 0
> error = cpu_cluster_pm_enter();
> if (error || !omap2_can_sleep()) {
> omap2_enter_mpu_retention();
> @@ -179,6 +191,9 @@ static void omap2_pm_idle(void)
>
> out_cpu_cluster_pm:
> cpu_cluster_pm_exit();
> +#else
> + omap2_do_wfi();
> +#endif
> }
>
> static void __init prcm_setup_regs(void)
The following commit has been merged into the sched/core branch of tip:
Commit-ID: a282e5ef2954e0bc2740c0c8c278f777933cc4fb
Gitweb: https://git.kernel.org/tip/a282e5ef2954e0bc2740c0c8c278f777933cc4fb
Author: Tony Lindgren <tony@atomide.com>
AuthorDate: Thu, 12 Jan 2023 20:43:52 +01:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Fri, 13 Jan 2023 11:48:17 +01:00
cpuidle, OMAP4: Push RCU-idle into omap4_enter_lowpower()
OMAP4 uses full SoC suspend modes as idle states, as such it needs the
whole power-domain and clock-domain code from the idle path.
All that code is not suitable to run with RCU disabled, as such push
RCU-idle deeper still.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/Yqcv6crSNKuSWoTu@atomide.com
Link: https://lore.kernel.org/r/20230112195541.660272394@infradead.org
---
arch/arm/mach-omap2/common.h | 6 ++++--
arch/arm/mach-omap2/cpuidle44xx.c | 8 ++------
arch/arm/mach-omap2/omap-mpuss-lowpower.c | 12 +++++++++++-
arch/arm/mach-omap2/pm44xx.c | 2 +-
4 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index bd59819..b745ff5 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -284,11 +284,13 @@ extern u32 omap4_get_cpu1_ns_pa_addr(void);
#if defined(CONFIG_SMP) && defined(CONFIG_PM)
extern int omap4_mpuss_init(void);
-extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state);
+extern int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
+ bool rcuidle);
extern int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state);
#else
static inline int omap4_enter_lowpower(unsigned int cpu,
- unsigned int power_state)
+ unsigned int power_state,
+ bool rcuidle)
{
cpu_do_idle();
return 0;
diff --git a/arch/arm/mach-omap2/cpuidle44xx.c b/arch/arm/mach-omap2/cpuidle44xx.c
index 3c97d56..df10652 100644
--- a/arch/arm/mach-omap2/cpuidle44xx.c
+++ b/arch/arm/mach-omap2/cpuidle44xx.c
@@ -105,9 +105,7 @@ static int omap_enter_idle_smp(struct cpuidle_device *dev,
}
raw_spin_unlock_irqrestore(&mpu_lock, flag);
- ct_cpuidle_enter();
- omap4_enter_lowpower(dev->cpu, cx->cpu_state);
- ct_cpuidle_exit();
+ omap4_enter_lowpower(dev->cpu, cx->cpu_state, true);
raw_spin_lock_irqsave(&mpu_lock, flag);
if (cx->mpu_state_vote == num_online_cpus())
@@ -186,10 +184,8 @@ static int omap_enter_idle_coupled(struct cpuidle_device *dev,
}
}
- ct_cpuidle_enter();
- omap4_enter_lowpower(dev->cpu, cx->cpu_state);
+ omap4_enter_lowpower(dev->cpu, cx->cpu_state, true);
cpu_done[dev->cpu] = true;
- ct_cpuidle_exit();
/* Wakeup CPU1 only if it is not offlined */
if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
index 9fba98c..7f29e17 100644
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -33,6 +33,7 @@
* and first to wake-up when MPUSS low power states are excercised
*/
+#include <linux/cpuidle.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/errno.h>
@@ -214,6 +215,7 @@ static void __init save_l2x0_context(void)
* of OMAP4 MPUSS subsystem
* @cpu : CPU ID
* @power_state: Low power state.
+ * @rcuidle: RCU needs to be idled
*
* MPUSS states for the context save:
* save_state =
@@ -222,7 +224,8 @@ static void __init save_l2x0_context(void)
* 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
* 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
*/
-int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
+int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state,
+ bool rcuidle)
{
struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET;
@@ -268,6 +271,10 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
cpu_clear_prev_logic_pwrst(cpu);
pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state);
+
+ if (rcuidle)
+ ct_cpuidle_enter();
+
set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.resume));
omap_pm_ops.scu_prepare(cpu, power_state);
l2x0_pwrst_prepare(cpu, save_state);
@@ -283,6 +290,9 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu)
gic_dist_enable();
+ if (rcuidle)
+ ct_cpuidle_exit();
+
/*
* Restore the CPUx power state to ON otherwise CPUx
* power domain can transitions to programmed low power
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index 5a7a949..f57802f 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c
@@ -76,7 +76,7 @@ static int omap4_pm_suspend(void)
* domain CSWR is not supported by hardware.
* More details can be found in OMAP4430 TRM section 4.3.4.2.
*/
- omap4_enter_lowpower(cpu_id, cpu_suspend_state);
+ omap4_enter_lowpower(cpu_id, cpu_suspend_state, false);
/* Restore next powerdomain state */
list_for_each_entry(pwrst, &pwrst_list, node) {© 2016 - 2024 Red Hat, Inc.