marvell/linux/drivers/soc/asr/debug/debugfs-asr.c

#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/cpufreq.h>


#define CPU_MIPS_LOOP   250000000
static unsigned int get_cpu_mips(void)
{
	struct timespec64 v1, v2;
	unsigned long cnt, total;
#ifdef CONFIG_ARM64
	unsigned long i;
#endif

	cnt = CPU_MIPS_LOOP;
	raw_local_irq_disable();
	ktime_get_real_ts64(&v1);
#ifdef CONFIG_ARM64
	__asm__ __volatile__(
			"mov %0, %1\n"
			"timer_loop:    subs    %0, %0, #1\n"
			"bhi     timer_loop"
			: "=&r" (i)
			: "r" (cnt)
			: "cc");
#else
	while (cnt--)
		barrier();
#endif
	ktime_get_real_ts64(&v2);
	raw_local_irq_enable();
	total = (v2.tv_sec - v1.tv_sec) * 1000000 + (v2.tv_nsec - v1.tv_nsec) / 1000;

	return CPU_MIPS_LOOP / total;
}

static ssize_t mips_read(struct file *filp, char __user *buffer,
		size_t count, loff_t *ppos)
{
	unsigned int mips, cpu;

	mips = get_cpu_mips();
	cpu = raw_smp_processor_id();
	pr_info("Attention! You need to keep cpufreq don't change!\n");
	pr_info("Calculated out MIPS is %dMhz, while setting is %dkhz\n",
			mips, cpufreq_get(cpu));
	return 0;
}

const struct file_operations show_mips_fops = {
	.read = mips_read,
};

struct dentry *asr_debug_entry;

static int __init asr_debugfs_init(void)
{
	struct dentry *showmips;

	asr_debug_entry = debugfs_create_dir("asr", NULL);
	if (!asr_debug_entry)
		return -ENOENT;

	showmips = debugfs_create_file("showmips", 0664,
					asr_debug_entry, NULL, &show_mips_fops);
	if (!showmips)
		goto err_mips;

	return 0;

err_mips:
	debugfs_remove(asr_debug_entry);
	asr_debug_entry = NULL;
return -ENOENT;
}

core_initcall_sync(asr_debugfs_init);