Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * i8253.c  8253/PIT functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <linux/clockchips.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <linux/i8253.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/smp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/irq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <asm/time.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) static irqreturn_t timer_interrupt(int irq, void *dev_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	i8253_clockevent.event_handler(&i8253_clockevent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	return IRQ_HANDLED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) void __init setup_pit_timer(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	unsigned long flags = IRQF_NOBALANCING | IRQF_TIMER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	clockevent_i8253_init(true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	if (request_irq(0, timer_interrupt, flags, "timer", NULL))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 		pr_err("Failed to request irq 0 (timer)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) static int __init init_pit_clocksource(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	if (num_possible_cpus() > 1 || /* PIT does not scale! */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	    !clockevent_state_periodic(&i8253_clockevent))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	return clocksource_i8253_init();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) arch_initcall(init_pit_clocksource);