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/mm.h>
15#include <linux/sched.h>
16#include <linux/seq_file.h>
17#include <linux/kallsyms.h>
18#include <linux/uaccess.h>
19
20#include <asm/irq.h>
21#include <asm/loongson.h>
22#include <asm/setup.h>
23
24DEFINE_PER_CPU(unsigned long, irq_stack);
25DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
26EXPORT_PER_CPU_SYMBOL(irq_stat);
27
28struct acpi_vector_group pch_group[MAX_IO_PICS];
29struct acpi_vector_group msi_group[MAX_IO_PICS];
30/*
31 * 'what should we do if we get a hw irq event on an illegal vector'.
32 * each architecture has to answer this themselves.
33 */
34void ack_bad_irq(unsigned int irq)
35{
36	pr_warn("Unexpected IRQ # %d\n", irq);
37}
38
39atomic_t irq_err_count;
40
41asmlinkage void spurious_interrupt(void)
42{
43	atomic_inc(&irq_err_count);
44}
45
46int arch_show_interrupts(struct seq_file *p, int prec)
47{
48#ifdef CONFIG_SMP
49	show_ipi_list(p, prec);
50#endif
51	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
52	return 0;
53}
54
55static int __init early_pci_mcfg_parse(struct acpi_table_header *header)
56{
57	struct acpi_table_mcfg *mcfg;
58	struct acpi_mcfg_allocation *mptr;
59	int i, n;
60
61	if (header->length < sizeof(struct acpi_table_mcfg))
62		return -EINVAL;
63
64	n = (header->length - sizeof(struct acpi_table_mcfg)) /
65					sizeof(struct acpi_mcfg_allocation);
66	mcfg = (struct acpi_table_mcfg *)header;
67	mptr = (struct acpi_mcfg_allocation *) &mcfg[1];
68
69	for (i = 0; i < n; i++, mptr++) {
70		msi_group[i].pci_segment = mptr->pci_segment;
71		pch_group[i].node = msi_group[i].node = (mptr->address >> 44) & 0xf;
72	}
73
74	return 0;
75}
76
77static void __init init_vec_parent_group(void)
78{
79	int i;
80
81	for (i = 0; i < MAX_IO_PICS; i++) {
82		msi_group[i].pci_segment = -1;
83		msi_group[i].node = -1;
84		pch_group[i].node = -1;
85	}
86
87	acpi_table_parse(ACPI_SIG_MCFG, early_pci_mcfg_parse);
88}
89
90static int __init get_ipi_irq(void)
91{
92	struct irq_domain *d = irq_find_matching_fwnode(cpuintc_handle, DOMAIN_BUS_ANY);
93
94	if (d)
95		return irq_create_mapping(d, INT_IPI);
96
97	return -EINVAL;
98}
99
100void __init init_IRQ(void)
101{
102	int i;
103#ifdef CONFIG_SMP
104	int r, ipi_irq;
105	static int ipi_dummy_dev;
106#endif
107	unsigned int order = get_order(IRQ_STACK_SIZE);
108	struct page *page;
109
110	clear_csr_ecfg(ECFG0_IM);
111	clear_csr_estat(ESTATF_IP);
112
113	init_vec_parent_group();
114	irqchip_init();
115#ifdef CONFIG_SMP
116	ipi_irq = get_ipi_irq();
117	if (ipi_irq < 0)
118		panic("IPI IRQ mapping failed\n");
119	irq_set_percpu_devid(ipi_irq);
120	r = request_percpu_irq(ipi_irq, loongson_ipi_interrupt, "IPI", &ipi_dummy_dev);
121	if (r < 0)
122		panic("IPI IRQ request failed\n");
123#endif
124
125	for (i = 0; i < NR_IRQS; i++)
126		irq_set_noprobe(i);
127
128	for_each_possible_cpu(i) {
129		page = alloc_pages_node(cpu_to_node(i), GFP_KERNEL, order);
130
131		per_cpu(irq_stack, i) = (unsigned long)page_address(page);
132		pr_debug("CPU%d IRQ stack at 0x%lx - 0x%lx\n", i,
133			per_cpu(irq_stack, i), per_cpu(irq_stack, i) + IRQ_STACK_SIZE);
134	}
135
136	set_csr_ecfg(ECFGF_IP0 | ECFGF_IP1 | ECFGF_IP2 | ECFGF_IPI | ECFGF_PMC);
137}
138