1 /*
2  *  linux/arch/arm/mach-mmp/irq-mmp2.c
3  *
4  *  Generic IRQ handling, GPIO IRQ demultiplexing, etc.
5  *
6  *  Author:	Haojian Zhuang <haojian.zhuang@marvell.com>
7  *  Copyright:	Marvell International Ltd.
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2 as
11  *  published by the Free Software Foundation.
12  */
13 
14 #include <linux/init.h>
15 #include <linux/irq.h>
16 #include <linux/io.h>
17 
18 #include <mach/regs-icu.h>
19 #include <mach/mmp2.h>
20 
21 #include "common.h"
22 
icu_mask_irq(struct irq_data * d)23 static void icu_mask_irq(struct irq_data *d)
24 {
25 	uint32_t r = __raw_readl(ICU_INT_CONF(d->irq));
26 
27 	r &= ~ICU_INT_ROUTE_PJ4_IRQ;
28 	__raw_writel(r, ICU_INT_CONF(d->irq));
29 }
30 
icu_unmask_irq(struct irq_data * d)31 static void icu_unmask_irq(struct irq_data *d)
32 {
33 	uint32_t r = __raw_readl(ICU_INT_CONF(d->irq));
34 
35 	r |= ICU_INT_ROUTE_PJ4_IRQ;
36 	__raw_writel(r, ICU_INT_CONF(d->irq));
37 }
38 
39 static struct irq_chip icu_irq_chip = {
40 	.name		= "icu_irq",
41 	.irq_mask	= icu_mask_irq,
42 	.irq_mask_ack	= icu_mask_irq,
43 	.irq_unmask	= icu_unmask_irq,
44 };
45 
pmic_irq_ack(struct irq_data * d)46 static void pmic_irq_ack(struct irq_data *d)
47 {
48 	if (d->irq == IRQ_MMP2_PMIC)
49 		mmp2_clear_pmic_int();
50 }
51 
52 #define SECOND_IRQ_MASK(_name_, irq_base, prefix)			\
53 static void _name_##_mask_irq(struct irq_data *d)			\
54 {									\
55 	uint32_t r;							\
56 	r = __raw_readl(prefix##_MASK) | (1 << (d->irq - irq_base));	\
57 	__raw_writel(r, prefix##_MASK);					\
58 }
59 
60 #define SECOND_IRQ_UNMASK(_name_, irq_base, prefix)			\
61 static void _name_##_unmask_irq(struct irq_data *d)			\
62 {									\
63 	uint32_t r;							\
64 	r = __raw_readl(prefix##_MASK) & ~(1 << (d->irq - irq_base));	\
65 	__raw_writel(r, prefix##_MASK);					\
66 }
67 
68 #define SECOND_IRQ_DEMUX(_name_, irq_base, prefix)			\
69 static void _name_##_irq_demux(unsigned int irq, struct irq_desc *desc)	\
70 {									\
71 	unsigned long status, mask, n;					\
72 	mask = __raw_readl(prefix##_MASK);				\
73 	while (1) {							\
74 		status = __raw_readl(prefix##_STATUS) & ~mask;		\
75 		if (status == 0)					\
76 			break;						\
77 		n = find_first_bit(&status, BITS_PER_LONG);		\
78 		while (n < BITS_PER_LONG) {				\
79 			generic_handle_irq(irq_base + n);		\
80 			n = find_next_bit(&status, BITS_PER_LONG, n+1);	\
81 		}							\
82 	}								\
83 }
84 
85 #define SECOND_IRQ_CHIP(_name_, irq_base, prefix)			\
86 SECOND_IRQ_MASK(_name_, irq_base, prefix)				\
87 SECOND_IRQ_UNMASK(_name_, irq_base, prefix)				\
88 SECOND_IRQ_DEMUX(_name_, irq_base, prefix)				\
89 static struct irq_chip _name_##_irq_chip = {				\
90 	.name		= #_name_,					\
91 	.irq_mask	= _name_##_mask_irq,				\
92 	.irq_unmask	= _name_##_unmask_irq,				\
93 }
94 
95 SECOND_IRQ_CHIP(pmic, IRQ_MMP2_PMIC_BASE, MMP2_ICU_INT4);
96 SECOND_IRQ_CHIP(rtc,  IRQ_MMP2_RTC_BASE,  MMP2_ICU_INT5);
97 SECOND_IRQ_CHIP(twsi, IRQ_MMP2_TWSI_BASE, MMP2_ICU_INT17);
98 SECOND_IRQ_CHIP(misc, IRQ_MMP2_MISC_BASE, MMP2_ICU_INT35);
99 SECOND_IRQ_CHIP(ssp,  IRQ_MMP2_SSP_BASE,  MMP2_ICU_INT51);
100 
init_mux_irq(struct irq_chip * chip,int start,int num)101 static void init_mux_irq(struct irq_chip *chip, int start, int num)
102 {
103 	int irq;
104 
105 	for (irq = start; num > 0; irq++, num--) {
106 		struct irq_data *d = irq_get_irq_data(irq);
107 
108 		/* mask and clear the IRQ */
109 		chip->irq_mask(d);
110 		if (chip->irq_ack)
111 			chip->irq_ack(d);
112 
113 		irq_set_chip(irq, chip);
114 		set_irq_flags(irq, IRQF_VALID);
115 		irq_set_handler(irq, handle_level_irq);
116 	}
117 }
118 
mmp2_init_icu(void)119 void __init mmp2_init_icu(void)
120 {
121 	int irq;
122 
123 	for (irq = 0; irq < IRQ_MMP2_MUX_BASE; irq++) {
124 		icu_mask_irq(irq_get_irq_data(irq));
125 		irq_set_chip(irq, &icu_irq_chip);
126 		set_irq_flags(irq, IRQF_VALID);
127 
128 		switch (irq) {
129 		case IRQ_MMP2_PMIC_MUX:
130 		case IRQ_MMP2_RTC_MUX:
131 		case IRQ_MMP2_TWSI_MUX:
132 		case IRQ_MMP2_MISC_MUX:
133 		case IRQ_MMP2_SSP_MUX:
134 			break;
135 		default:
136 			irq_set_handler(irq, handle_level_irq);
137 			break;
138 		}
139 	}
140 
141 	/* NOTE: IRQ_MMP2_PMIC requires the PMIC MFPR register
142 	 * to be written to clear the interrupt
143 	 */
144 	pmic_irq_chip.irq_ack = pmic_irq_ack;
145 
146 	init_mux_irq(&pmic_irq_chip, IRQ_MMP2_PMIC_BASE, 2);
147 	init_mux_irq(&rtc_irq_chip, IRQ_MMP2_RTC_BASE, 2);
148 	init_mux_irq(&twsi_irq_chip, IRQ_MMP2_TWSI_BASE, 5);
149 	init_mux_irq(&misc_irq_chip, IRQ_MMP2_MISC_BASE, 15);
150 	init_mux_irq(&ssp_irq_chip, IRQ_MMP2_SSP_BASE, 2);
151 
152 	irq_set_chained_handler(IRQ_MMP2_PMIC_MUX, pmic_irq_demux);
153 	irq_set_chained_handler(IRQ_MMP2_RTC_MUX, rtc_irq_demux);
154 	irq_set_chained_handler(IRQ_MMP2_TWSI_MUX, twsi_irq_demux);
155 	irq_set_chained_handler(IRQ_MMP2_MISC_MUX, misc_irq_demux);
156 	irq_set_chained_handler(IRQ_MMP2_SSP_MUX, ssp_irq_demux);
157 }
158