static void armv6_pmu_stop(void)
{
arm11_stop_pmu();
arm11_release_interrupts(pmu_irqs->irqs, pmu_irqs->num_irqs);
release_pmu(pmu_irqs);
pmu_irqs = NULL;
}
static void em_stop(void)
{
em_call_function(arm11_stop_pmu);
arm11_release_interrupts(pmu_irqs->irqs, pmu_irqs->num_irqs);
scu_stop();
release_pmu(pmu_irqs);
}
static int em_start(void)
{
int ret;
pmu_irqs = reserve_pmu();
if (IS_ERR(pmu_irqs)) {
ret = PTR_ERR(pmu_irqs);
goto out;
}
ret = arm11_request_interrupts(pmu_irqs->irqs, pmu_irqs->num_irqs);
if (ret == 0) {
em_call_function(arm11_start_pmu);
ret = scu_start();
if (ret) {
arm11_release_interrupts(pmu_irqs->irqs,
pmu_irqs->num_irqs);
} else {
release_pmu(pmu_irqs);
pmu_irqs = NULL;
}
}
out:
return ret;
}
static void gator_event_sampling_stop(void)
{
#if LINUX_PMU_SUPPORT
if (event_based_sampling) {
int i, irq;
for (i = pmu_device->num_resources - 1; i >= 0; --i) {
irq = platform_get_irq(pmu_device, i);
if (irq >= 0)
free_irq(irq, NULL);
}
}
if (!IS_ERR(pmu_device)) {
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0)
release_pmu(pmu_device);
#else
release_pmu(ARM_PMU_DEVICE_CPU);
#endif
}
pmu_device = NULL;
#endif
}
static int armv6_pmu_start(void)
{
int ret;
pmu_irqs = reserve_pmu();
if (IS_ERR(pmu_irqs)) {
ret = PTR_ERR(pmu_irqs);
goto out;
}
ret = arm11_request_interrupts(pmu_irqs->irqs, pmu_irqs->num_irqs);
if (ret >= 0) {
ret = arm11_start_pmu();
} else {
release_pmu(pmu_irqs);
pmu_irqs = NULL;
}
out:
return ret;
}
static int gator_event_sampling_start(void)
{
int cnt;
event_based_sampling = false;
for (cnt = CCNT; cnt < CNTMAX; cnt++) {
if (pmnc_count[cnt] > 0) {
event_based_sampling = true;
break;
}
}
#if LINUX_PMU_SUPPORT
pmu_device = reserve_pmu(ARM_PMU_DEVICE_CPU);
if (IS_ERR(pmu_device) && (unsigned int)pmu_device != -ENODEV) {
pr_err("gator: unable to reserve the pmu\n");
return -1;
}
if (event_based_sampling) {
int irq, i;
if (IS_ERR(pmu_device)) {
pr_err("gator: event based sampling is not supported as the kernel function reserve_pmu() failed\n");
return -1;
}
// init_pmu sets the irq affinity, therefore we do not care if it fails for single core
if (init_pmu(ARM_PMU_DEVICE_CPU) != 0 && gator_cpu_cores > 1) {
pr_err("gator: unable to initialize the pmu\n");
goto out_ebs_start;
}
if (pmu_device->num_resources == 0) {
pr_err("gator: no irqs for PMUs defined\n");
goto out_ebs_start;
}
for (i = 0; i < pmu_device->num_resources; ++i) {
irq = platform_get_irq(pmu_device, i);
if (irq < 0)
continue;
if (request_irq(irq, armv7_pmnc_interrupt, IRQF_DISABLED | IRQF_NOBALANCING, "armpmu", NULL)) {
pr_err("gator: unable to request IRQ%d for ARM perf counters\n", irq);
// clean up and exit
for (i = i - 1; i >= 0; --i) {
irq = platform_get_irq(pmu_device, i);
if (irq >= 0)
free_irq(irq, NULL);
}
goto out_ebs_start;
}
}
}
#else
if (event_based_sampling) {
pr_err("gator: event based sampling only supported in kernel versions 2.6.35 and higher and CONFIG_CPU_HAS_PMU=y\n");
return -1;
}
#endif
return 0;
#if LINUX_PMU_SUPPORT
out_ebs_start:
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0)
release_pmu(pmu_device);
#else
release_pmu(ARM_PMU_DEVICE_CPU);
#endif
pmu_device = NULL;
return -1;
#endif
}
