xref: /openbmc/linux/arch/arc/kernel/irq.c (revision 0545810f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com)
4  */
5 
6 #include <linux/interrupt.h>
7 #include <linux/irqchip.h>
8 #include <asm/mach_desc.h>
9 
10 #include <asm/irq_regs.h>
11 #include <asm/smp.h>
12 
13 /*
14  * Late Interrupt system init called from start_kernel for Boot CPU only
15  *
16  * Since slab must already be initialized, platforms can start doing any
17  * needed request_irq( )s
18  */
19 void __init init_IRQ(void)
20 {
21 	/*
22 	 * process the entire interrupt tree in one go
23 	 * Any external intc will be setup provided DT chains them
24 	 * properly
25 	 */
26 	irqchip_init();
27 
28 #ifdef CONFIG_SMP
29 	/* a SMP H/w block could do IPI IRQ request here */
30 	if (plat_smp_ops.init_per_cpu)
31 		plat_smp_ops.init_per_cpu(smp_processor_id());
32 #endif
33 
34 	if (machine_desc->init_per_cpu)
35 		machine_desc->init_per_cpu(smp_processor_id());
36 }
37 
38 /*
39  * "C" Entry point for any ARC ISR, called from low level vector handler
40  * @irq is the vector number read from ICAUSE reg of on-chip intc
41  */
42 void arch_do_IRQ(unsigned int hwirq, struct pt_regs *regs)
43 {
44 	struct pt_regs *old_regs;
45 
46 	irq_enter();
47 	old_regs = set_irq_regs(regs);
48 	generic_handle_domain_irq(NULL, hwirq);
49 	set_irq_regs(old_regs);
50 	irq_exit();
51 }
52