xref: /openbmc/linux/arch/sh/boards/mach-se/7724/irq.c (revision 020c5260)
1 /*
2  * linux/arch/sh/boards/se/7724/irq.c
3  *
4  * Copyright (C) 2009 Renesas Solutions Corp.
5  *
6  * Kuninori Morimoto <morimoto.kuninori@renesas.com>
7  *
8  * Based on  linux/arch/sh/boards/se/7722/irq.c
9  * Copyright (C) 2007  Nobuhiro Iwamatsu
10  *
11  * Hitachi UL SolutionEngine 7724 Support.
12  *
13  * This file is subject to the terms and conditions of the GNU General Public
14  * License.  See the file "COPYING" in the main directory of this archive
15  * for more details.
16  */
17 #include <linux/init.h>
18 #include <linux/irq.h>
19 #include <linux/interrupt.h>
20 #include <linux/export.h>
21 #include <linux/topology.h>
22 #include <linux/io.h>
23 #include <linux/err.h>
24 #include <mach-se/mach/se7724.h>
25 
26 struct fpga_irq {
27 	unsigned long  sraddr;
28 	unsigned long  mraddr;
29 	unsigned short mask;
30 	unsigned int   base;
31 };
32 
33 static unsigned int fpga2irq(unsigned int irq)
34 {
35 	if (irq >= IRQ0_BASE &&
36 	    irq <= IRQ0_END)
37 		return IRQ0_IRQ;
38 	else if (irq >= IRQ1_BASE &&
39 		 irq <= IRQ1_END)
40 		return IRQ1_IRQ;
41 	else
42 		return IRQ2_IRQ;
43 }
44 
45 static struct fpga_irq get_fpga_irq(unsigned int irq)
46 {
47 	struct fpga_irq set;
48 
49 	switch (irq) {
50 	case IRQ0_IRQ:
51 		set.sraddr = IRQ0_SR;
52 		set.mraddr = IRQ0_MR;
53 		set.mask   = IRQ0_MASK;
54 		set.base   = IRQ0_BASE;
55 		break;
56 	case IRQ1_IRQ:
57 		set.sraddr = IRQ1_SR;
58 		set.mraddr = IRQ1_MR;
59 		set.mask   = IRQ1_MASK;
60 		set.base   = IRQ1_BASE;
61 		break;
62 	default:
63 		set.sraddr = IRQ2_SR;
64 		set.mraddr = IRQ2_MR;
65 		set.mask   = IRQ2_MASK;
66 		set.base   = IRQ2_BASE;
67 		break;
68 	}
69 
70 	return set;
71 }
72 
73 static void disable_se7724_irq(struct irq_data *data)
74 {
75 	unsigned int irq = data->irq;
76 	struct fpga_irq set = get_fpga_irq(fpga2irq(irq));
77 	unsigned int bit = irq - set.base;
78 	__raw_writew(__raw_readw(set.mraddr) | 0x0001 << bit, set.mraddr);
79 }
80 
81 static void enable_se7724_irq(struct irq_data *data)
82 {
83 	unsigned int irq = data->irq;
84 	struct fpga_irq set = get_fpga_irq(fpga2irq(irq));
85 	unsigned int bit = irq - set.base;
86 	__raw_writew(__raw_readw(set.mraddr) & ~(0x0001 << bit), set.mraddr);
87 }
88 
89 static struct irq_chip se7724_irq_chip __read_mostly = {
90 	.name		= "SE7724-FPGA",
91 	.irq_mask	= disable_se7724_irq,
92 	.irq_unmask	= enable_se7724_irq,
93 };
94 
95 static void se7724_irq_demux(struct irq_desc *desc)
96 {
97 	unsigned int irq = irq_desc_get_irq(desc);
98 	struct fpga_irq set = get_fpga_irq(irq);
99 	unsigned short intv = __raw_readw(set.sraddr);
100 	unsigned int ext_irq = set.base;
101 
102 	intv &= set.mask;
103 
104 	for (; intv; intv >>= 1, ext_irq++) {
105 		if (!(intv & 1))
106 			continue;
107 
108 		generic_handle_irq(ext_irq);
109 	}
110 }
111 
112 /*
113  * Initialize IRQ setting
114  */
115 void __init init_se7724_IRQ(void)
116 {
117 	int irq_base, i;
118 
119 	__raw_writew(0xffff, IRQ0_MR);  /* mask all */
120 	__raw_writew(0xffff, IRQ1_MR);  /* mask all */
121 	__raw_writew(0xffff, IRQ2_MR);  /* mask all */
122 	__raw_writew(0x0000, IRQ0_SR);  /* clear irq */
123 	__raw_writew(0x0000, IRQ1_SR);  /* clear irq */
124 	__raw_writew(0x0000, IRQ2_SR);  /* clear irq */
125 	__raw_writew(0x002a, IRQ_MODE); /* set irq type */
126 
127 	irq_base = irq_alloc_descs(SE7724_FPGA_IRQ_BASE, SE7724_FPGA_IRQ_BASE,
128 				   SE7724_FPGA_IRQ_NR, numa_node_id());
129 	if (IS_ERR_VALUE(irq_base)) {
130 		pr_err("%s: failed hooking irqs for FPGA\n", __func__);
131 		return;
132 	}
133 
134 	for (i = 0; i < SE7724_FPGA_IRQ_NR; i++)
135 		irq_set_chip_and_handler_name(irq_base + i, &se7724_irq_chip,
136 					      handle_level_irq, "level");
137 
138 	irq_set_chained_handler(IRQ0_IRQ, se7724_irq_demux);
139 	irq_set_irq_type(IRQ0_IRQ, IRQ_TYPE_LEVEL_LOW);
140 
141 	irq_set_chained_handler(IRQ1_IRQ, se7724_irq_demux);
142 	irq_set_irq_type(IRQ1_IRQ, IRQ_TYPE_LEVEL_LOW);
143 
144 	irq_set_chained_handler(IRQ2_IRQ, se7724_irq_demux);
145 	irq_set_irq_type(IRQ2_IRQ, IRQ_TYPE_LEVEL_LOW);
146 }
147