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hwtracing/coresight-etm4x: Convert to hotplug state machine 

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>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.228918408@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
hifive-unleashed-5.1
Sebastian Andrzej Siewior 2016-07-13 17:16:55 +00:00 committed by Ingo Molnar
parent 2b5283d12f
commit 58eb457be0
2 changed files with 52 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

91
drivers/hwtracing/coresight/coresight-etm4x.c
View File

@ -48,6 +48,8 @@ static int etm4_count;
static struct etmv4_drvdata *etmdrvdata[NR_CPUS];
static void etm4_set_default(struct etmv4_config *config);
static enum cpuhp_state hp_online;
static void etm4_os_unlock(struct etmv4_drvdata *drvdata)
{
/* Writing any value to ETMOSLAR unlocks the trace registers */
@ -673,47 +675,44 @@ void etm4_config_trace_mode(struct etmv4_config *config)
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])
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;
if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
coresight_enable(etmdrvdata[cpu]->csdev);
return 0;
}
static struct notifier_block etm4_cpu_notifier = {
.notifier_call = etm4_cpu_callback,
};
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])
return 0;
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)
{
@ -767,8 +766,17 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
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 *adev, const struct amba_id *id)
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;
}

1
include/linux/cpuhotplug.h
View File

@ -50,6 +50,7 @@ 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,