1// SPDX-License-Identifier: GPL-2.0
2/*
3 *	Copyright (C) 2000 YAEGASHI Takeshi
4 *	Hitachi HD64461 companion chip support
5 */
6
7#include <linux/sched.h>
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/param.h>
11#include <linux/interrupt.h>
12#include <linux/init.h>
13#include <linux/irq.h>
14#include <linux/io.h>
15#include <asm/irq.h>
16#include <asm/hd64461.h>
17
18/* This belongs in cpu specific */
19#define INTC_ICR1 0xA4140010UL
20
21static void hd64461_mask_irq(struct irq_data *data)
22{
23	unsigned int irq = data->irq;
24	unsigned short nimr;
25	unsigned short mask = 1 << (irq - HD64461_IRQBASE);
26
27	nimr = __raw_readw(HD64461_NIMR);
28	nimr |= mask;
29	__raw_writew(nimr, HD64461_NIMR);
30}
31
32static void hd64461_unmask_irq(struct irq_data *data)
33{
34	unsigned int irq = data->irq;
35	unsigned short nimr;
36	unsigned short mask = 1 << (irq - HD64461_IRQBASE);
37
38	nimr = __raw_readw(HD64461_NIMR);
39	nimr &= ~mask;
40	__raw_writew(nimr, HD64461_NIMR);
41}
42
43static void hd64461_mask_and_ack_irq(struct irq_data *data)
44{
45	hd64461_mask_irq(data);
46
47#ifdef CONFIG_HD64461_ENABLER
48	if (data->irq == HD64461_IRQBASE + 13)
49		__raw_writeb(0x00, HD64461_PCC1CSCR);
50#endif
51}
52
53static struct irq_chip hd64461_irq_chip = {
54	.name		= "HD64461-IRQ",
55	.irq_mask	= hd64461_mask_irq,
56	.irq_mask_ack	= hd64461_mask_and_ack_irq,
57	.irq_unmask	= hd64461_unmask_irq,
58};
59
60static void hd64461_irq_demux(struct irq_desc *desc)
61{
62	unsigned short intv = __raw_readw(HD64461_NIRR);
63	unsigned int ext_irq = HD64461_IRQBASE;
64
65	intv &= (1 << HD64461_IRQ_NUM) - 1;
66
67	for (; intv; intv >>= 1, ext_irq++) {
68		if (!(intv & 1))
69			continue;
70
71		generic_handle_irq(ext_irq);
72	}
73}
74
75int __init setup_hd64461(void)
76{
77	int irq_base, i;
78
79	printk(KERN_INFO
80	       "HD64461 configured at 0x%x on irq %d(mapped into %d to %d)\n",
81	       HD64461_IOBASE, CONFIG_HD64461_IRQ, HD64461_IRQBASE,
82	       HD64461_IRQBASE + 15);
83
84/* Should be at processor specific part.. */
85#if defined(CONFIG_CPU_SUBTYPE_SH7709)
86	__raw_writew(0x2240, INTC_ICR1);
87#endif
88	__raw_writew(0xffff, HD64461_NIMR);
89
90	irq_base = irq_alloc_descs(HD64461_IRQBASE, HD64461_IRQBASE, 16, -1);
91	if (IS_ERR_VALUE(irq_base)) {
92		pr_err("%s: failed hooking irqs for HD64461\n", __func__);
93		return irq_base;
94	}
95
96	for (i = 0; i < 16; i++)
97		irq_set_chip_and_handler(irq_base + i, &hd64461_irq_chip,
98					 handle_level_irq);
99
100	irq_set_chained_handler(CONFIG_HD64461_IRQ, hd64461_irq_demux);
101	irq_set_irq_type(CONFIG_HD64461_IRQ, IRQ_TYPE_LEVEL_LOW);
102
103#ifdef CONFIG_HD64461_ENABLER
104	printk(KERN_INFO "HD64461: enabling PCMCIA devices\n");
105	__raw_writeb(0x4c, HD64461_PCC1CSCIER);
106	__raw_writeb(0x00, HD64461_PCC1CSCR);
107#endif
108
109	return 0;
110}
111
112module_init(setup_hd64461);
113