xref: /linux/arch/loongarch/kernel/irq.c (revision dc30127cd050dbc9d8452846ee7fa6692a1093d2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #include <linux/kernel.h>
6 #include <linux/acpi.h>
7 #include <linux/atomic.h>
8 #include <linux/delay.h>
9 #include <linux/init.h>
10 #include <linux/interrupt.h>
11 #include <linux/irqchip.h>
12 #include <linux/kernel_stat.h>
13 #include <linux/proc_fs.h>
14 #include <linux/minmax.h>
15 #include <linux/mm.h>
16 #include <linux/sched.h>
17 #include <linux/seq_file.h>
18 #include <linux/kallsyms.h>
19 #include <linux/uaccess.h>
20 
21 #include <asm/irq.h>
22 #include <asm/loongson.h>
23 #include <asm/setup.h>
24 
25 DEFINE_PER_CPU(unsigned long, irq_stack);
26 DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
27 EXPORT_PER_CPU_SYMBOL(irq_stat);
28 
29 struct acpi_vector_group pch_group[MAX_IO_PICS];
30 struct acpi_vector_group msi_group[MAX_IO_PICS];
31 /*
32  * 'what should we do if we get a hw irq event on an illegal vector'.
33  * each architecture has to answer this themselves.
34  */
35 void ack_bad_irq(unsigned int irq)
36 {
37 	pr_warn("Unexpected IRQ # %d\n", irq);
38 }
39 
40 atomic_t irq_err_count;
41 
42 asmlinkage void spurious_interrupt(void)
43 {
44 	atomic_inc(&irq_err_count);
45 }
46 
47 int arch_show_interrupts(struct seq_file *p, int prec)
48 {
49 #ifdef CONFIG_SMP
50 	show_ipi_list(p, prec);
51 #endif
52 	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
53 	return 0;
54 }
55 
56 static int __init early_pci_mcfg_parse(struct acpi_table_header *header)
57 {
58 	struct acpi_table_mcfg *mcfg;
59 	struct acpi_mcfg_allocation *mptr;
60 	int i, n;
61 
62 	if (header->length < sizeof(struct acpi_table_mcfg))
63 		return -EINVAL;
64 
65 	n = (header->length - sizeof(struct acpi_table_mcfg)) /
66 					sizeof(struct acpi_mcfg_allocation);
67 	mcfg = (struct acpi_table_mcfg *)header;
68 	mptr = (struct acpi_mcfg_allocation *) &mcfg[1];
69 
70 	for (i = 0; i < n; i++, mptr++) {
71 		msi_group[i].pci_segment = mptr->pci_segment;
72 		pch_group[i].node = msi_group[i].node = (mptr->address >> 44) & 0xf;
73 	}
74 
75 	return 0;
76 }
77 
78 static void __init init_vec_parent_group(void)
79 {
80 	int i;
81 
82 	for (i = 0; i < MAX_IO_PICS; i++) {
83 		msi_group[i].pci_segment = -1;
84 		msi_group[i].node = -1;
85 		pch_group[i].node = -1;
86 	}
87 
88 	acpi_table_parse(ACPI_SIG_MCFG, early_pci_mcfg_parse);
89 }
90 
91 int __init arch_probe_nr_irqs(void)
92 {
93 	int nr_io_pics = bitmap_weight(loongson_sysconf.cores_io_master, NR_CPUS);
94 
95 	if (!cpu_has_avecint)
96 		irq_set_nr_irqs(64 + NR_VECTORS * nr_io_pics);
97 	else
98 		irq_set_nr_irqs(64 + NR_VECTORS * (nr_cpu_ids + nr_io_pics));
99 
100 	return NR_IRQS_LEGACY;
101 }
102 
103 unsigned int arch_dynirq_lower_bound(unsigned int from)
104 {
105 	return MAX(from, NR_IRQS_LEGACY);
106 }
107 
108 void __init init_IRQ(void)
109 {
110 	int i;
111 	unsigned int order = get_order(IRQ_STACK_SIZE);
112 	struct page *page;
113 
114 	clear_csr_ecfg(ECFG0_IM);
115 	clear_csr_estat(ESTATF_IP);
116 
117 	init_vec_parent_group();
118 	irqchip_init();
119 #ifdef CONFIG_SMP
120 	mp_ops.init_ipi();
121 #endif
122 
123 	for_each_possible_cpu(i) {
124 		page = alloc_pages_node(cpu_to_node(i), GFP_KERNEL, order);
125 
126 		per_cpu(irq_stack, i) = (unsigned long)page_address(page);
127 		pr_debug("CPU%d IRQ stack at 0x%lx - 0x%lx\n", i,
128 			per_cpu(irq_stack, i), per_cpu(irq_stack, i) + IRQ_STACK_SIZE);
129 	}
130 
131 	set_csr_ecfg(ECFGF_SIP0 | ECFGF_IP0 | ECFGF_IP1 | ECFGF_IP2 | ECFGF_IPI | ECFGF_PMC);
132 }
133