[patch 07/66] ARM: mvebu: Convert to hotplug state machine

[patch 07/66] ARM: mvebu: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/arm/mach-mvebu/coherency.c |   19 ++++++-------------
 include/linux/cpuhotplug.h      |    1 +
 2 files changed, 7 insertions(+), 13 deletions(-)

--- a/arch/arm/mach-mvebu/coherency.c
+++ b/arch/arm/mach-mvebu/coherency.c
@@ -111,20 +111,12 @@ static struct notifier_block mvebu_hwcc_
 	.notifier_call = mvebu_hwcc_notifier,
 };
 
-static int armada_xp_clear_shared_l2_notifier_func(struct notifier_block *nfb,
-					unsigned long action, void *hcpu)
+static int armada_xp_clear_l2_starting(unsigned int cpu)
 {
-	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
-		armada_xp_clear_shared_l2();
-
-	return NOTIFY_OK;
+	armada_xp_clear_shared_l2();
+	return 0;
 }
 
-static struct notifier_block armada_xp_clear_shared_l2_notifier = {
-	.notifier_call = armada_xp_clear_shared_l2_notifier_func,
-	.priority = 100,
-};
-
 static void __init armada_370_coherency_init(struct device_node *np)
 {
 	struct resource res;
@@ -155,8 +147,9 @@ static void __init armada_370_coherency_
 
 	of_node_put(cpu_config_np);
 
-	register_cpu_notifier(&armada_xp_clear_shared_l2_notifier);
-
+	cpuhp_setup_state_nocalls(CPUHP_AP_ARM_MVEBU_COHERENCY,
+				  "AP_ARM_MVEBU_COHERENCY",
+				  armada_xp_clear_l2_starting, NULL);
 exit:
 	set_cpu_coherent();
 }
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -15,6 +15,7 @@ enum cpuhp_state {
 	CPUHP_AP_IRQ_ARMADA_XP_STARTING,
 	CPUHP_AP_IRQ_ARMADA_CASC_STARTING,
 	CPUHP_AP_IRQ_BCM2836_STARTING,
+	CPUHP_AP_ARM_MVEBU_COHERENCY,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,
 	CPUHP_TEARDOWN_CPU,

[patch 33/66] arm: Convert VFP hotplug notifiers to state machine

[Anna-Maria Gleixner]

From: Thomas Gleixner <tglx@linutronix.de>

Straight forward conversion plus commentary why code which is executed
in hotplug callbacks needs to be invoked before installing them.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel at lists.infradead.org

---
 arch/arm/vfp/vfpmodule.c   |   28 +++++++++++++++++-----------
 include/linux/cpuhotplug.h |    1 +
 2 files changed, 18 insertions(+), 11 deletions(-)

--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -643,19 +643,19 @@ int vfp_restore_user_hwstate(struct user
  * hardware state at every thread switch.  We clear our held state when
  * a CPU has been killed, indicating that the VFP hardware doesn't contain
  * a threads VFP state.  When a CPU starts up, we re-enable access to the
- * VFP hardware.
- *
- * Both CPU_DYING and CPU_STARTING are called on the CPU which
+ * VFP hardware. The callbacks below are called on the CPU which
  * is being offlined/onlined.
  */
-static int vfp_hotplug(struct notifier_block *b, unsigned long action,
-	void *hcpu)
+static int vfp_dying_cpu(unsigned int cpu)
 {
-	if (action == CPU_DYING || action == CPU_DYING_FROZEN)
-		vfp_current_hw_state[(long)hcpu] = NULL;
-	else if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
-		vfp_enable(NULL);
-	return NOTIFY_OK;
+	vfp_force_reload(cpu, current_thread_info());
+	return 0;
+}
+
+static int vfp_starting_cpu(unsigned int unused)
+{
+	vfp_enable(NULL);
+	return 0;
 }
 
 void vfp_kmode_exception(void)
@@ -732,6 +732,10 @@ static int __init vfp_init(void)
 	unsigned int vfpsid;
 	unsigned int cpu_arch = cpu_architecture();
 
+	/*
+	 * Enable the access to the VFP on all online CPUs so the
+	 * following test on FPSID will succeed.
+	 */
 	if (cpu_arch >= CPU_ARCH_ARMv6)
 		on_each_cpu(vfp_enable, NULL, 1);
 
@@ -794,7 +798,9 @@ static int __init vfp_init(void)
 		VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT;
 	}
 
-	hotcpu_notifier(vfp_hotplug, 0);
+	cpuhp_setup_state_nocalls(CPUHP_AP_ARM_VFP_STARTING,
+				  "AP_ARM_VFP_STARTING", vfp_starting_cpu,
+				  vfp_dying_cpu);
 
 	vfp_vector = vfp_support_entry;
 
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -35,6 +35,7 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_X86_CQM_STARTING,
 	CPUHP_AP_PERF_X86_CSTATE_STARTING,
 	CPUHP_AP_PERF_XTENSA_STARTING,
+	CPUHP_AP_ARM_VFP_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,
 	CPUHP_TEARDOWN_CPU,

[patch 38/66] clocksource/arm_global_timer: Convert to hotplug state machine.

[Anna-Maria Gleixner]

From: Richard Cochran <rcochran@linutronix.de>

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-arm-kernel at lists.infradead.org
Cc: kernel at stlinux.com
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>

---
 drivers/clocksource/arm_global_timer.c |   41 ++++++++-------------------------
 include/linux/cpuhotplug.h             |    1 
 2 files changed, 11 insertions(+), 31 deletions(-)

--- a/drivers/clocksource/arm_global_timer.c
+++ b/drivers/clocksource/arm_global_timer.c
@@ -165,9 +165,9 @@ static irqreturn_t gt_clockevent_interru
 	return IRQ_HANDLED;
 }
 
-static int gt_clockevents_init(struct clock_event_device *clk)
+static int gt_starting_cpu(unsigned int cpu)
 {
-	int cpu = smp_processor_id();
+	struct clock_event_device *clk = this_cpu_ptr(gt_evt);
 
 	clk->name = "arm_global_timer";
 	clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
@@ -186,10 +186,13 @@ static int gt_clockevents_init(struct cl
 	return 0;
 }
 
-static void gt_clockevents_stop(struct clock_event_device *clk)
+static int gt_dying_cpu(unsigned int cpu)
 {
+	struct clock_event_device *clk = this_cpu_ptr(gt_evt);
+
 	gt_clockevent_shutdown(clk);
 	disable_percpu_irq(clk->irq);
+	return 0;
 }
 
 static cycle_t gt_clocksource_read(struct clocksource *cs)
@@ -252,24 +255,6 @@ static void __init gt_clocksource_init(v
 	clocksource_register_hz(&gt_clocksource, gt_clk_rate);
 }
 
-static int gt_cpu_notify(struct notifier_block *self, unsigned long action,
-			 void *hcpu)
-{
-	switch (action & ~CPU_TASKS_FROZEN) {
-	case CPU_STARTING:
-		gt_clockevents_init(this_cpu_ptr(gt_evt));
-		break;
-	case CPU_DYING:
-		gt_clockevents_stop(this_cpu_ptr(gt_evt));
-		break;
-	}
-
-	return NOTIFY_OK;
-}
-static struct notifier_block gt_cpu_nb = {
-	.notifier_call = gt_cpu_notify,
-};
-
 static void __init global_timer_of_register(struct device_node *np)
 {
 	struct clk *gt_clk;
@@ -325,21 +310,15 @@ static void __init global_timer_of_regis
 		goto out_free;
 	}
 
-	err = register_cpu_notifier(&gt_cpu_nb);
-	if (err) {
-		pr_warn("global-timer: unable to register cpu notifier.\n");
-		goto out_irq;
-	}
-
-	/* Immediately configure the timer on the boot CPU */
+	/* Register and immediately configure the timer on the boot CPU */
 	gt_clocksource_init();
-	gt_clockevents_init(this_cpu_ptr(gt_evt));
+	cpuhp_setup_state(CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
+			  "AP_ARM_GLOBAL_TIMER_STARTING", gt_starting_cpu,
+			  gt_dying_cpu);
 	gt_delay_timer_init();
 
 	return;
 
-out_irq:
-	free_percpu_irq(gt_ppi, gt_evt);
 out_free:
 	free_percpu(gt_evt);
 out_clk:
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -38,6 +38,7 @@ enum cpuhp_state {
 	CPUHP_AP_ARM_VFP_STARTING,
 	CPUHP_AP_PERF_ARM_STARTING,
 	CPUHP_AP_ARM_ARCH_TIMER_STARTING,
+	CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
 	CPUHP_AP_KVM_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,

[patch 50/66] arm: l2c: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Richard Cochran <rcochran@linutronix.de>

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>

---
 arch/arm/mm/cache-l2x0.c   |   27 +++++++++++++--------------
 include/linux/cpuhotplug.h |    1 +
 2 files changed, 14 insertions(+), 14 deletions(-)

--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -597,17 +597,16 @@ static void l2c310_configure(void __iome
 			      L310_POWER_CTRL);
 }
 
-static int l2c310_cpu_enable_flz(struct notifier_block *nb, unsigned long act, void *data)
+static int l2c310_starting_cpu(unsigned int cpu)
 {
-	switch (act & ~CPU_TASKS_FROZEN) {
-	case CPU_STARTING:
-		set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
-		break;
-	case CPU_DYING:
-		set_auxcr(get_auxcr() & ~(BIT(3) | BIT(2) | BIT(1)));
-		break;
-	}
-	return NOTIFY_OK;
+	set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
+	return 0;
+}
+
+static int l2c310_dying_cpu(unsigned int cpu)
+{
+	set_auxcr(get_auxcr() & ~(BIT(3) | BIT(2) | BIT(1)));
+	return 0;
 }
 
 static void __init l2c310_enable(void __iomem *base, unsigned num_lock)
@@ -678,10 +677,10 @@ static void __init l2c310_enable(void __
 			power_ctrl & L310_STNDBY_MODE_EN ? "en" : "dis");
 	}
 
-	if (aux & L310_AUX_CTRL_FULL_LINE_ZERO) {
-		set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
-		cpu_notifier(l2c310_cpu_enable_flz, 0);
-	}
+	if (aux & L310_AUX_CTRL_FULL_LINE_ZERO)
+		cpuhp_setup_state(CPUHP_AP_ARM_L2X0_STARTING,
+				  "AP_ARM_L2X0_STARTING", l2c310_starting_cpu,
+				  l2c310_dying_cpu);
 }
 
 static void __init l2c310_fixup(void __iomem *base, u32 cache_id,
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -38,6 +38,7 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_METAG_STARTING,
 	CPUHP_AP_ARM_VFP_STARTING,
 	CPUHP_AP_PERF_ARM_STARTING,
+	CPUHP_AP_ARM_L2X0_STARTING,
 	CPUHP_AP_ARM_ARCH_TIMER_STARTING,
 	CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
 	CPUHP_AP_DUMMY_TIMER_STARTING,

[patch 51/66] arm: twd: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Richard Cochran <rcochran@linutronix.de>

Install the callbacks via the state machine. The callbacks won't be invoked on
already online CPUs.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/arm/kernel/smp_twd.c  |   31 +++++++++++--------------------
 include/linux/cpuhotplug.h |    1 +
 2 files changed, 12 insertions(+), 20 deletions(-)

--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -310,24 +310,17 @@ static void twd_timer_setup(void)
 	enable_percpu_irq(clk->irq, 0);
 }
 
-static int twd_timer_cpu_notify(struct notifier_block *self,
-				unsigned long action, void *hcpu)
+static int twd_timer_starting_cpu(unsigned int cpu)
 {
-	switch (action & ~CPU_TASKS_FROZEN) {
-	case CPU_STARTING:
-		twd_timer_setup();
-		break;
-	case CPU_DYING:
-		twd_timer_stop();
-		break;
-	}
-
-	return NOTIFY_OK;
+	twd_timer_setup();
+	return 0;
 }
 
-static struct notifier_block twd_timer_cpu_nb = {
-	.notifier_call = twd_timer_cpu_notify,
-};
+static int twd_timer_dying_cpu(unsigned int cpu)
+{
+	twd_timer_stop();
+	return 0;
+}
 
 static int __init twd_local_timer_common_register(struct device_node *np)
 {
@@ -345,9 +338,9 @@ static int __init twd_local_timer_common
 		goto out_free;
 	}
 
-	err = register_cpu_notifier(&twd_timer_cpu_nb);
-	if (err)
-		goto out_irq;
+	cpuhp_setup_state_nocalls(CPUHP_AP_ARM_TWD_STARTING,
+				  "AP_ARM_TWD_STARTING",
+				  twd_timer_starting_cpu, twd_timer_dying_cpu);
 
 	twd_get_clock(np);
 	if (!of_property_read_bool(np, "always-on"))
@@ -365,8 +358,6 @@ static int __init twd_local_timer_common
 
 	return 0;
 
-out_irq:
-	free_percpu_irq(twd_ppi, twd_evt);
 out_free:
 	iounmap(twd_base);
 	twd_base = NULL;
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -42,6 +42,7 @@ enum cpuhp_state {
 	CPUHP_AP_ARM_ARCH_TIMER_STARTING,
 	CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
 	CPUHP_AP_DUMMY_TIMER_STARTING,
+	CPUHP_AP_ARM_TWD_STARTING,
 	CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
 	CPUHP_AP_METAG_TIMER_STARTING,
 	CPUHP_AP_QCOM_TIMER_STARTING,

[patch 55/66] hwtracing: coresight-etm4x: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

This driver has an asymmetry of ONLINE code without any corresponding tear
down code. Otherwise, this is a straightforward conversion.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 drivers/hwtracing/coresight/coresight-etm4x.c |   93 ++++++++++++++------------
 include/linux/cpuhotplug.h                    |    1 
 2 files changed, 53 insertions(+), 41 deletions(-)

--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -673,53 +673,52 @@ void etm4_config_trace_mode(struct etmv4
 	config->addr_acc[ETM_DEFAULT_ADDR_COMP + 1] = addr_acc;
 }
 
-static int etm4_cpu_callback(struct notifier_block *nfb, unsigned long action,
-			    void *hcpu)
+static int etm4_online_cpu(unsigned int cpu)
 {
-	unsigned int cpu = (unsigned long)hcpu;
+	if (!etmdrvdata[cpu])
+		return 0;
+
+	if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
+		coresight_enable(etmdrvdata[cpu]->csdev);
+	return 0;
+}
+
+static int etm4_starting_cpu(unsigned int cpu)
+{
+	if (!etmdrvdata[cpu])
+		return 0;
+
+	spin_lock(&etmdrvdata[cpu]->spinlock);
+	if (!etmdrvdata[cpu]->os_unlock) {
+		etm4_os_unlock(etmdrvdata[cpu]);
+		etmdrvdata[cpu]->os_unlock = true;
+	}
 
+	if (local_read(&etmdrvdata[cpu]->mode))
+		etm4_enable_hw(etmdrvdata[cpu]);
+	spin_unlock(&etmdrvdata[cpu]->spinlock);
+	return 0;
+}
+
+static int etm4_dying_cpu(unsigned int cpu)
+{
 	if (!etmdrvdata[cpu])
-		goto out;
+		return 0;
 
-	switch (action & (~CPU_TASKS_FROZEN)) {
-	case CPU_STARTING:
-		spin_lock(&etmdrvdata[cpu]->spinlock);
-		if (!etmdrvdata[cpu]->os_unlock) {
-			etm4_os_unlock(etmdrvdata[cpu]);
-			etmdrvdata[cpu]->os_unlock = true;
-		}
-
-		if (local_read(&etmdrvdata[cpu]->mode))
-			etm4_enable_hw(etmdrvdata[cpu]);
-		spin_unlock(&etmdrvdata[cpu]->spinlock);
-		break;
-
-	case CPU_ONLINE:
-		if (etmdrvdata[cpu]->boot_enable &&
-			!etmdrvdata[cpu]->sticky_enable)
-			coresight_enable(etmdrvdata[cpu]->csdev);
-		break;
-
-	case CPU_DYING:
-		spin_lock(&etmdrvdata[cpu]->spinlock);
-		if (local_read(&etmdrvdata[cpu]->mode))
-			etm4_disable_hw(etmdrvdata[cpu]);
-		spin_unlock(&etmdrvdata[cpu]->spinlock);
-		break;
-	}
-out:
-	return NOTIFY_OK;
-}
-
-static struct notifier_block etm4_cpu_notifier = {
-	.notifier_call = etm4_cpu_callback,
-};
+	spin_lock(&etmdrvdata[cpu]->spinlock);
+	if (local_read(&etmdrvdata[cpu]->mode))
+		etm4_disable_hw(etmdrvdata[cpu]);
+	spin_unlock(&etmdrvdata[cpu]->spinlock);
+	return 0;
+}
 
 static void etm4_init_trace_id(struct etmv4_drvdata *drvdata)
 {
 	drvdata->trcid = coresight_get_trace_id(drvdata->cpu);
 }
 
+static enum cpuhp_state hp_online;
+
 static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
 {
 	int ret;
@@ -767,8 +766,17 @@ static int etm4_probe(struct amba_device
 				etm4_init_arch_data,  drvdata, 1))
 		dev_err(dev, "ETM arch init failed\n");
 
-	if (!etm4_count++)
-		register_hotcpu_notifier(&etm4_cpu_notifier);
+	if (!etm4_count++) {
+		cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT4_STARTING,
+					  "AP_ARM_CORESIGHT4_STARTING",
+					  etm4_starting_cpu, etm4_dying_cpu);
+		ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+						"AP_ARM_CORESIGHT4_ONLINE",
+						etm4_online_cpu, NULL);
+		if (ret < 0)
+			goto err_arch_supported;
+		hp_online = ret;
+	}
 
 	put_online_cpus();
 
@@ -809,8 +817,11 @@ static int etm4_probe(struct amba_device
 	return 0;
 
 err_arch_supported:
-	if (--etm4_count == 0)
-		unregister_hotcpu_notifier(&etm4_cpu_notifier);
+	if (--etm4_count == 0) {
+		cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT4_STARTING);
+		if (hp_online)
+			cpuhp_remove_state_nocalls(hp_online);
+	}
 	return ret;
 }
 
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -55,6 +55,7 @@ enum cpuhp_state {
 	CPUHP_AP_KVM_ARM_TIMER_STARTING,
 	CPUHP_AP_ARM_XEN_STARTING,
 	CPUHP_AP_ARM_CORESIGHT_STARTING,
+	CPUHP_AP_ARM_CORESIGHT4_STARTING,
 	CPUHP_AP_LEDTRIG_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,

[patch 54/66] hwtracing: coresight-etm3x: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Richard Cochran <rcochran@linutronix.de>

This driver has an asymmetry of ONLINE code without any corresponding tear
down code. Otherwise, this is a straightforward conversion.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>

---
 drivers/hwtracing/coresight/coresight-etm3x.c |   90 ++++++++++++++------------
 include/linux/cpuhotplug.h                    |    1 
 2 files changed, 50 insertions(+), 41 deletions(-)

--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -481,8 +481,7 @@ static int etm_enable_sysfs(struct cores
 
 	/*
 	 * Configure the ETM only if the CPU is online.  If it isn't online
-	 * hw configuration will take place when 'CPU_STARTING' is received
-	 * in @etm_cpu_callback.
+	 * hw configuration will take place on the local CPU during bring up.
 	 */
 	if (cpu_online(drvdata->cpu)) {
 		ret = smp_call_function_single(drvdata->cpu,
@@ -641,47 +640,44 @@ static const struct coresight_ops etm_cs
 	.source_ops	= &etm_source_ops,
 };
 
-static int etm_cpu_callback(struct notifier_block *nfb, unsigned long action,
-			    void *hcpu)
+static int etm_online_cpu(unsigned int cpu)
 {
-	unsigned int cpu = (unsigned long)hcpu;
-
 	if (!etmdrvdata[cpu])
-		goto out;
+		return 0;
 
-	switch (action & (~CPU_TASKS_FROZEN)) {
-	case CPU_STARTING:
-		spin_lock(&etmdrvdata[cpu]->spinlock);
-		if (!etmdrvdata[cpu]->os_unlock) {
-			etm_os_unlock(etmdrvdata[cpu]);
-			etmdrvdata[cpu]->os_unlock = true;
-		}
-
-		if (local_read(&etmdrvdata[cpu]->mode))
-			etm_enable_hw(etmdrvdata[cpu]);
-		spin_unlock(&etmdrvdata[cpu]->spinlock);
-		break;
+	if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
+		coresight_enable(etmdrvdata[cpu]->csdev);
+	return 0;
+}
 
-	case CPU_ONLINE:
-		if (etmdrvdata[cpu]->boot_enable &&
-		    !etmdrvdata[cpu]->sticky_enable)
-			coresight_enable(etmdrvdata[cpu]->csdev);
-		break;
+static int etm_starting_cpu(unsigned int cpu)
+{
+	if (!etmdrvdata[cpu])
+		return 0;
 
-	case CPU_DYING:
-		spin_lock(&etmdrvdata[cpu]->spinlock);
-		if (local_read(&etmdrvdata[cpu]->mode))
-			etm_disable_hw(etmdrvdata[cpu]);
-		spin_unlock(&etmdrvdata[cpu]->spinlock);
-		break;
+	spin_lock(&etmdrvdata[cpu]->spinlock);
+	if (!etmdrvdata[cpu]->os_unlock) {
+		etm_os_unlock(etmdrvdata[cpu]);
+		etmdrvdata[cpu]->os_unlock = true;
 	}
-out:
-	return NOTIFY_OK;
+
+	if (local_read(&etmdrvdata[cpu]->mode))
+		etm_enable_hw(etmdrvdata[cpu]);
+	spin_unlock(&etmdrvdata[cpu]->spinlock);
+	return 0;
 }
 
-static struct notifier_block etm_cpu_notifier = {
-	.notifier_call = etm_cpu_callback,
-};
+static int etm_dying_cpu(unsigned int cpu)
+{
+	if (!etmdrvdata[cpu])
+		return 0;
+
+	spin_lock(&etmdrvdata[cpu]->spinlock);
+	if (local_read(&etmdrvdata[cpu]->mode))
+		etm_disable_hw(etmdrvdata[cpu]);
+	spin_unlock(&etmdrvdata[cpu]->spinlock);
+	return 0;
+}
 
 static bool etm_arch_supported(u8 arch)
 {
@@ -750,6 +746,8 @@ static void etm_init_trace_id(struct etm
 	drvdata->traceid = coresight_get_trace_id(drvdata->cpu);
 }
 
+static enum cpuhp_state hp_online;
+
 static int etm_probe(struct amba_device *adev, const struct amba_id *id)
 {
 	int ret;
@@ -806,9 +804,17 @@ static int etm_probe(struct amba_device
 				     etm_init_arch_data,  drvdata, 1))
 		dev_err(dev, "ETM arch init failed\n");
 
-	if (!etm_count++)
-		register_hotcpu_notifier(&etm_cpu_notifier);
-
+	if (!etm_count++) {
+		cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING,
+					  "AP_ARM_CORESIGHT_STARTING",
+					  etm_starting_cpu, etm_dying_cpu);
+		ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+						"AP_ARM_CORESIGHT_ONLINE",
+						etm_online_cpu, NULL);
+		if (ret < 0)
+			goto err_arch_supported;
+		hp_online = ret;
+	}
 	put_online_cpus();
 
 	if (etm_arch_supported(drvdata->arch) == false) {
@@ -839,7 +845,6 @@ static int etm_probe(struct amba_device
 
 	pm_runtime_put(&adev->dev);
 	dev_info(dev, "%s initialized\n", (char *)id->data);
-
 	if (boot_enable) {
 		coresight_enable(drvdata->csdev);
 		drvdata->boot_enable = true;
@@ -848,8 +853,11 @@ static int etm_probe(struct amba_device
 	return 0;
 
 err_arch_supported:
-	if (--etm_count == 0)
-		unregister_hotcpu_notifier(&etm_cpu_notifier);
+	if (--etm_count == 0) {
+		cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
+		if (hp_online)
+			cpuhp_remove_state_nocalls(hp_online);
+	}
 	return ret;
 }
 
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -54,6 +54,7 @@ enum cpuhp_state {
 	CPUHP_AP_KVM_ARM_VGIC_STARTING,
 	CPUHP_AP_KVM_ARM_TIMER_STARTING,
 	CPUHP_AP_ARM_XEN_STARTING,
+	CPUHP_AP_ARM_CORESIGHT_STARTING,
 	CPUHP_AP_LEDTRIG_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,

[patch 56/66] arm64: armv8 deprecated: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
 arch/arm64/kernel/armv8_deprecated.c |   22 +++++-----------------
 include/linux/cpuhotplug.h           |    1 +
 2 files changed, 6 insertions(+), 17 deletions(-)

--- a/arch/arm64/kernel/armv8_deprecated.c
+++ b/arch/arm64/kernel/armv8_deprecated.c
@@ -121,7 +121,7 @@ static int run_all_cpu_set_hw_mode(struc
  *  0 		- If all the hooks ran successfully.
  * -EINVAL	- At least one hook is not supported by the CPU.
  */
-static int run_all_insn_set_hw_mode(unsigned long cpu)
+static int run_all_insn_set_hw_mode(unsigned int cpu)
 {
 	int rc = 0;
 	unsigned long flags;
@@ -131,7 +131,7 @@ static int run_all_insn_set_hw_mode(unsi
 	list_for_each_entry(insn, &insn_emulation, node) {
 		bool enable = (insn->current_mode == INSN_HW);
 		if (insn->ops->set_hw_mode && insn->ops->set_hw_mode(enable)) {
-			pr_warn("CPU[%ld] cannot support the emulation of %s",
+			pr_warn("CPU[%u] cannot support the emulation of %s",
 				cpu, insn->ops->name);
 			rc = -EINVAL;
 		}
@@ -617,20 +617,6 @@ static struct insn_emulation_ops setend_
 	.set_hw_mode = setend_set_hw_mode,
 };
 
-static int insn_cpu_hotplug_notify(struct notifier_block *b,
-			      unsigned long action, void *hcpu)
-{
-	int rc = 0;
-	if ((action & ~CPU_TASKS_FROZEN) == CPU_STARTING)
-		rc = run_all_insn_set_hw_mode((unsigned long)hcpu);
-
-	return notifier_from_errno(rc);
-}
-
-static struct notifier_block insn_cpu_hotplug_notifier = {
-	.notifier_call = insn_cpu_hotplug_notify,
-};
-
 /*
  * Invoked as late_initcall, since not needed before init spawned.
  */
@@ -649,7 +635,9 @@ static int __init armv8_deprecated_init(
 			pr_info("setend instruction emulation is not supported on the system");
 	}
 
-	register_cpu_notifier(&insn_cpu_hotplug_notifier);
+	cpuhp_setup_state_nocalls(CPUHP_AP_ARM64_ISNDEP_STARTING,
+				  "AP_ARM64_ISNDEP_STARTING",
+				  run_all_insn_set_hw_mode, NULL);
 	register_insn_emulation_sysctl(ctl_abi);
 
 	return 0;
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -56,6 +56,7 @@ enum cpuhp_state {
 	CPUHP_AP_ARM_XEN_STARTING,
 	CPUHP_AP_ARM_CORESIGHT_STARTING,
 	CPUHP_AP_ARM_CORESIGHT4_STARTING,
+	CPUHP_AP_ARM64_ISNDEP_STARTING,
 	CPUHP_AP_LEDTRIG_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,

[patch 54/66] hwtracing: coresight-etm3x: Convert to hotplug state machine

[Mathieu Poirier]

On 11 July 2016 at 06:29, Anna-Maria Gleixner <anna-maria@linutronix.de> wrote:
> From: Richard Cochran <rcochran@linutronix.de>
>
> This driver has an asymmetry of ONLINE code without any corresponding tear
> down code. Otherwise, this is a straightforward conversion.
>
> Signed-off-by: Richard Cochran <rcochran@linutronix.de>
> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
>
> ---
>  drivers/hwtracing/coresight/coresight-etm3x.c |   90 ++++++++++++++------------
>  include/linux/cpuhotplug.h                    |    1
>  2 files changed, 50 insertions(+), 41 deletions(-)
>
> --- a/drivers/hwtracing/coresight/coresight-etm3x.c
> +++ b/drivers/hwtracing/coresight/coresight-etm3x.c
> @@ -481,8 +481,7 @@ static int etm_enable_sysfs(struct cores
>
>         /*
>          * Configure the ETM only if the CPU is online.  If it isn't online
> -        * hw configuration will take place when 'CPU_STARTING' is received
> -        * in @etm_cpu_callback.
> +        * hw configuration will take place on the local CPU during bring up.
>          */
>         if (cpu_online(drvdata->cpu)) {
>                 ret = smp_call_function_single(drvdata->cpu,
> @@ -641,47 +640,44 @@ static const struct coresight_ops etm_cs
>         .source_ops     = &etm_source_ops,
>  };
>
> -static int etm_cpu_callback(struct notifier_block *nfb, unsigned long action,
> -                           void *hcpu)
> +static int etm_online_cpu(unsigned int cpu)
>  {
> -       unsigned int cpu = (unsigned long)hcpu;
> -
>         if (!etmdrvdata[cpu])
> -               goto out;
> +               return 0;
>
> -       switch (action & (~CPU_TASKS_FROZEN)) {
> -       case CPU_STARTING:
> -               spin_lock(&etmdrvdata[cpu]->spinlock);
> -               if (!etmdrvdata[cpu]->os_unlock) {
> -                       etm_os_unlock(etmdrvdata[cpu]);
> -                       etmdrvdata[cpu]->os_unlock = true;
> -               }
> -
> -               if (local_read(&etmdrvdata[cpu]->mode))
> -                       etm_enable_hw(etmdrvdata[cpu]);
> -               spin_unlock(&etmdrvdata[cpu]->spinlock);
> -               break;
> +       if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
> +               coresight_enable(etmdrvdata[cpu]->csdev);
> +       return 0;
> +}
>
> -       case CPU_ONLINE:
> -               if (etmdrvdata[cpu]->boot_enable &&
> -                   !etmdrvdata[cpu]->sticky_enable)
> -                       coresight_enable(etmdrvdata[cpu]->csdev);
> -               break;
> +static int etm_starting_cpu(unsigned int cpu)
> +{
> +       if (!etmdrvdata[cpu])
> +               return 0;
>
> -       case CPU_DYING:
> -               spin_lock(&etmdrvdata[cpu]->spinlock);
> -               if (local_read(&etmdrvdata[cpu]->mode))
> -                       etm_disable_hw(etmdrvdata[cpu]);
> -               spin_unlock(&etmdrvdata[cpu]->spinlock);
> -               break;
> +       spin_lock(&etmdrvdata[cpu]->spinlock);
> +       if (!etmdrvdata[cpu]->os_unlock) {
> +               etm_os_unlock(etmdrvdata[cpu]);
> +               etmdrvdata[cpu]->os_unlock = true;
>         }
> -out:
> -       return NOTIFY_OK;
> +
> +       if (local_read(&etmdrvdata[cpu]->mode))
> +               etm_enable_hw(etmdrvdata[cpu]);
> +       spin_unlock(&etmdrvdata[cpu]->spinlock);
> +       return 0;
>  }
>
> -static struct notifier_block etm_cpu_notifier = {
> -       .notifier_call = etm_cpu_callback,
> -};
> +static int etm_dying_cpu(unsigned int cpu)
> +{
> +       if (!etmdrvdata[cpu])
> +               return 0;
> +
> +       spin_lock(&etmdrvdata[cpu]->spinlock);
> +       if (local_read(&etmdrvdata[cpu]->mode))
> +               etm_disable_hw(etmdrvdata[cpu]);
> +       spin_unlock(&etmdrvdata[cpu]->spinlock);
> +       return 0;
> +}
>
>  static bool etm_arch_supported(u8 arch)
>  {
> @@ -750,6 +746,8 @@ static void etm_init_trace_id(struct etm
>         drvdata->traceid = coresight_get_trace_id(drvdata->cpu);
>  }
>
> +static enum cpuhp_state hp_online;
> +

Can we put this at the top of the file with the other global declaration?

>  static int etm_probe(struct amba_device *adev, const struct amba_id *id)
>  {
>         int ret;
> @@ -806,9 +804,17 @@ static int etm_probe(struct amba_device
>                                      etm_init_arch_data,  drvdata, 1))
>                 dev_err(dev, "ETM arch init failed\n");
>
> -       if (!etm_count++)
> -               register_hotcpu_notifier(&etm_cpu_notifier);
> -
> +       if (!etm_count++) {
> +               cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING,
> +                                         "AP_ARM_CORESIGHT_STARTING",
> +                                         etm_starting_cpu, etm_dying_cpu);
> +               ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
> +                                               "AP_ARM_CORESIGHT_ONLINE",
> +                                               etm_online_cpu, NULL);
> +               if (ret < 0)
> +                       goto err_arch_supported;
> +               hp_online = ret;
> +       }
>         put_online_cpus();
>
>         if (etm_arch_supported(drvdata->arch) == false) {
> @@ -839,7 +845,6 @@ static int etm_probe(struct amba_device
>
>         pm_runtime_put(&adev->dev);
>         dev_info(dev, "%s initialized\n", (char *)id->data);
> -
>         if (boot_enable) {
>                 coresight_enable(drvdata->csdev);
>                 drvdata->boot_enable = true;
> @@ -848,8 +853,11 @@ static int etm_probe(struct amba_device
>         return 0;
>
>  err_arch_supported:
> -       if (--etm_count == 0)
> -               unregister_hotcpu_notifier(&etm_cpu_notifier);
> +       if (--etm_count == 0) {
> +               cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
> +               if (hp_online)
> +                       cpuhp_remove_state_nocalls(hp_online);
> +       }
>         return ret;
>  }
>
> --- a/include/linux/cpuhotplug.h
> +++ b/include/linux/cpuhotplug.h
> @@ -54,6 +54,7 @@ enum cpuhp_state {
>         CPUHP_AP_KVM_ARM_VGIC_STARTING,
>         CPUHP_AP_KVM_ARM_TIMER_STARTING,
>         CPUHP_AP_ARM_XEN_STARTING,
> +       CPUHP_AP_ARM_CORESIGHT_STARTING,
>         CPUHP_AP_LEDTRIG_STARTING,
>         CPUHP_AP_NOTIFY_STARTING,
>         CPUHP_AP_ONLINE,
>
>

This looks good to me - thanks for contribution.  With the above change,

Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>

[patch 55/66] hwtracing: coresight-etm4x: Convert to hotplug state machine

[Mathieu Poirier]

On 11 July 2016 at 06:29, Anna-Maria Gleixner <anna-maria@linutronix.de> wrote:
> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>
> This driver has an asymmetry of ONLINE code without any corresponding tear
> down code. Otherwise, this is a straightforward conversion.
>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
> ---
>  drivers/hwtracing/coresight/coresight-etm4x.c |   93 ++++++++++++++------------
>  include/linux/cpuhotplug.h                    |    1
>  2 files changed, 53 insertions(+), 41 deletions(-)
>
> --- a/drivers/hwtracing/coresight/coresight-etm4x.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.c
> @@ -673,53 +673,52 @@ void etm4_config_trace_mode(struct etmv4
>         config->addr_acc[ETM_DEFAULT_ADDR_COMP + 1] = addr_acc;
>  }
>
> -static int etm4_cpu_callback(struct notifier_block *nfb, unsigned long action,
> -                           void *hcpu)
> +static int etm4_online_cpu(unsigned int cpu)
>  {
> -       unsigned int cpu = (unsigned long)hcpu;
> +       if (!etmdrvdata[cpu])
> +               return 0;
> +
> +       if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
> +               coresight_enable(etmdrvdata[cpu]->csdev);
> +       return 0;
> +}
> +
> +static int etm4_starting_cpu(unsigned int cpu)
> +{
> +       if (!etmdrvdata[cpu])
> +               return 0;
> +
> +       spin_lock(&etmdrvdata[cpu]->spinlock);
> +       if (!etmdrvdata[cpu]->os_unlock) {
> +               etm4_os_unlock(etmdrvdata[cpu]);
> +               etmdrvdata[cpu]->os_unlock = true;
> +       }
>
> +       if (local_read(&etmdrvdata[cpu]->mode))
> +               etm4_enable_hw(etmdrvdata[cpu]);
> +       spin_unlock(&etmdrvdata[cpu]->spinlock);
> +       return 0;
> +}
> +
> +static int etm4_dying_cpu(unsigned int cpu)
> +{
>         if (!etmdrvdata[cpu])
> -               goto out;
> +               return 0;
>
> -       switch (action & (~CPU_TASKS_FROZEN)) {
> -       case CPU_STARTING:
> -               spin_lock(&etmdrvdata[cpu]->spinlock);
> -               if (!etmdrvdata[cpu]->os_unlock) {
> -                       etm4_os_unlock(etmdrvdata[cpu]);
> -                       etmdrvdata[cpu]->os_unlock = true;
> -               }
> -
> -               if (local_read(&etmdrvdata[cpu]->mode))
> -                       etm4_enable_hw(etmdrvdata[cpu]);
> -               spin_unlock(&etmdrvdata[cpu]->spinlock);
> -               break;
> -
> -       case CPU_ONLINE:
> -               if (etmdrvdata[cpu]->boot_enable &&
> -                       !etmdrvdata[cpu]->sticky_enable)
> -                       coresight_enable(etmdrvdata[cpu]->csdev);
> -               break;
> -
> -       case CPU_DYING:
> -               spin_lock(&etmdrvdata[cpu]->spinlock);
> -               if (local_read(&etmdrvdata[cpu]->mode))
> -                       etm4_disable_hw(etmdrvdata[cpu]);
> -               spin_unlock(&etmdrvdata[cpu]->spinlock);
> -               break;
> -       }
> -out:
> -       return NOTIFY_OK;
> -}
> -
> -static struct notifier_block etm4_cpu_notifier = {
> -       .notifier_call = etm4_cpu_callback,
> -};
> +       spin_lock(&etmdrvdata[cpu]->spinlock);
> +       if (local_read(&etmdrvdata[cpu]->mode))
> +               etm4_disable_hw(etmdrvdata[cpu]);
> +       spin_unlock(&etmdrvdata[cpu]->spinlock);
> +       return 0;
> +}
>
>  static void etm4_init_trace_id(struct etmv4_drvdata *drvdata)
>  {
>         drvdata->trcid = coresight_get_trace_id(drvdata->cpu);
>  }
>
> +static enum cpuhp_state hp_online;
> +

Same comment as with ETMv3 - I'd like to see this at the top of the
file with the rest of the global declaration.

>  static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
>  {
>         int ret;
> @@ -767,8 +766,17 @@ static int etm4_probe(struct amba_device
>                                 etm4_init_arch_data,  drvdata, 1))
>                 dev_err(dev, "ETM arch init failed\n");
>
> -       if (!etm4_count++)
> -               register_hotcpu_notifier(&etm4_cpu_notifier);
> +       if (!etm4_count++) {
> +               cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT4_STARTING,
> +                                         "AP_ARM_CORESIGHT4_STARTING",
> +                                         etm4_starting_cpu, etm4_dying_cpu);
> +               ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
> +                                               "AP_ARM_CORESIGHT4_ONLINE",
> +                                               etm4_online_cpu, NULL);
> +               if (ret < 0)
> +                       goto err_arch_supported;
> +               hp_online = ret;
> +       }
>
>         put_online_cpus();
>
> @@ -809,8 +817,11 @@ static int etm4_probe(struct amba_device
>         return 0;
>
>  err_arch_supported:
> -       if (--etm4_count == 0)
> -               unregister_hotcpu_notifier(&etm4_cpu_notifier);
> +       if (--etm4_count == 0) {
> +               cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT4_STARTING);
> +               if (hp_online)
> +                       cpuhp_remove_state_nocalls(hp_online);
> +       }
>         return ret;
>  }
>
> --- a/include/linux/cpuhotplug.h
> +++ b/include/linux/cpuhotplug.h
> @@ -55,6 +55,7 @@ enum cpuhp_state {
>         CPUHP_AP_KVM_ARM_TIMER_STARTING,
>         CPUHP_AP_ARM_XEN_STARTING,
>         CPUHP_AP_ARM_CORESIGHT_STARTING,
> +       CPUHP_AP_ARM_CORESIGHT4_STARTING,
>         CPUHP_AP_LEDTRIG_STARTING,
>         CPUHP_AP_NOTIFY_STARTING,
>         CPUHP_AP_ONLINE,
>
>

With the above change,

Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>