arch/arc/kernel/setup.c

Source file repositories/reference/linux-study-clean/arch/arc/kernel/setup.c

File Facts

System
Linux kernel
Corpus path
arch/arc/kernel/setup.c
Extension
.c
Size
16514 bytes
Lines
655
Domain
Architecture Layer
Bucket
arch/arc
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

* Called from start_kernel() - boot CPU only
 */
void __init time_init(void)
{
	of_clk_init(NULL);
	timer_probe();
}

static int __init customize_machine(void)
{
	if (machine_desc->init_machine)
		machine_desc->init_machine();

	return 0;
}
arch_initcall(customize_machine);

static int __init init_late_machine(void)
{
	if (machine_desc->init_late)
		machine_desc->init_late();

	return 0;
}
late_initcall(init_late_machine);
/*
 *  Get CPU information for use by the procfs.
 */

#define cpu_to_ptr(c)	((void *)(0xFFFF0000 | (unsigned int)(c)))
#define ptr_to_cpu(p)	(~0xFFFF0000UL & (unsigned int)(p))

static int show_cpuinfo(struct seq_file *m, void *v)
{
	char *str;
	int cpu_id = ptr_to_cpu(v);
	struct device *cpu_dev = get_cpu_device(cpu_id);
	struct cpuinfo_arc info;
	struct clk *cpu_clk;
	unsigned long freq = 0;

	if (!cpu_online(cpu_id)) {
		seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
		goto done;
	}

	str = (char *)__get_free_page(GFP_KERNEL);
	if (!str)
		goto done;

	seq_printf(m, arc_cpu_mumbojumbo(cpu_id, &info, str, PAGE_SIZE));

	cpu_clk = clk_get(cpu_dev, NULL);
	if (IS_ERR(cpu_clk)) {
		seq_printf(m, "CPU speed \t: Cannot get clock for processor [%d]\n",
			   cpu_id);
	} else {
		freq = clk_get_rate(cpu_clk);
	}
	if (freq)
		seq_printf(m, "CPU speed\t: %lu.%02lu Mhz\n",
			   freq / 1000000, (freq / 10000) % 100);

	seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
		   loops_per_jiffy / (500000 / HZ),
		   (loops_per_jiffy / (5000 / HZ)) % 100);

	seq_printf(m, arc_platform_smp_cpuinfo());

	free_page((unsigned long)str);
done:
	seq_printf(m, "\n");

	return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	/*
	 * Callback returns cpu-id to iterator for show routine, NULL to stop.
	 * However since NULL is also a valid cpu-id (0), we use a round-about
	 * way to pass it w/o having to kmalloc/free a 2 byte string.
	 * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
	 */
	return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
	++*pos;

Annotation

Implementation Notes