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
21 static 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
32 static 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
43 static 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
53 static 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
60 static 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
75 static int __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
112 module_init(setup_hd64461);
113
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