xref: /linux/drivers/sh/intc/chip.c (revision 06c7a489a97fce99fd86611f6f32e565e686e5d8)
1 /*
2  * IRQ chip definitions for INTC IRQs.
3  *
4  * Copyright (C) 2007, 2008 Magnus Damm
5  * Copyright (C) 2009, 2010 Paul Mundt
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file "COPYING" in the main directory of this archive
9  * for more details.
10  */
11 #include <linux/cpumask.h>
12 #include <linux/io.h>
13 #include "internals.h"
14 
15 void _intc_enable(unsigned int irq, unsigned long handle)
16 {
17 	struct intc_desc_int *d = get_intc_desc(irq);
18 	unsigned long addr;
19 	unsigned int cpu;
20 
21 	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_E(handle)); cpu++) {
22 #ifdef CONFIG_SMP
23 		if (!cpumask_test_cpu(cpu, irq_to_desc(irq)->affinity))
24 			continue;
25 #endif
26 		addr = INTC_REG(d, _INTC_ADDR_E(handle), cpu);
27 		intc_enable_fns[_INTC_MODE(handle)](addr, handle, intc_reg_fns\
28 						    [_INTC_FN(handle)], irq);
29 	}
30 
31 	intc_balancing_enable(irq);
32 }
33 
34 static void intc_enable(unsigned int irq)
35 {
36 	_intc_enable(irq, (unsigned long)get_irq_chip_data(irq));
37 }
38 
39 static void intc_disable(unsigned int irq)
40 {
41 	struct intc_desc_int *d = get_intc_desc(irq);
42 	unsigned long handle = (unsigned long)get_irq_chip_data(irq);
43 	unsigned long addr;
44 	unsigned int cpu;
45 
46 	intc_balancing_disable(irq);
47 
48 	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_D(handle)); cpu++) {
49 #ifdef CONFIG_SMP
50 		if (!cpumask_test_cpu(cpu, irq_to_desc(irq)->affinity))
51 			continue;
52 #endif
53 		addr = INTC_REG(d, _INTC_ADDR_D(handle), cpu);
54 		intc_disable_fns[_INTC_MODE(handle)](addr, handle,intc_reg_fns\
55 						     [_INTC_FN(handle)], irq);
56 	}
57 }
58 
59 static int intc_set_wake(unsigned int irq, unsigned int on)
60 {
61 	return 0; /* allow wakeup, but setup hardware in intc_suspend() */
62 }
63 
64 #ifdef CONFIG_SMP
65 /*
66  * This is held with the irq desc lock held, so we don't require any
67  * additional locking here at the intc desc level. The affinity mask is
68  * later tested in the enable/disable paths.
69  */
70 static int intc_set_affinity(unsigned int irq, const struct cpumask *cpumask)
71 {
72 	if (!cpumask_intersects(cpumask, cpu_online_mask))
73 		return -1;
74 
75 	cpumask_copy(irq_to_desc(irq)->affinity, cpumask);
76 
77 	return 0;
78 }
79 #endif
80 
81 static void intc_mask_ack(unsigned int irq)
82 {
83 	struct intc_desc_int *d = get_intc_desc(irq);
84 	unsigned long handle = intc_get_ack_handle(irq);
85 	unsigned long addr;
86 
87 	intc_disable(irq);
88 
89 	/* read register and write zero only to the associated bit */
90 	if (handle) {
91 		unsigned int value;
92 
93 		addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
94 		value = intc_set_field_from_handle(0, 1, handle);
95 
96 		switch (_INTC_FN(handle)) {
97 		case REG_FN_MODIFY_BASE + 0:	/* 8bit */
98 			__raw_readb(addr);
99 			__raw_writeb(0xff ^ value, addr);
100 			break;
101 		case REG_FN_MODIFY_BASE + 1:	/* 16bit */
102 			__raw_readw(addr);
103 			__raw_writew(0xffff ^ value, addr);
104 			break;
105 		case REG_FN_MODIFY_BASE + 3:	/* 32bit */
106 			__raw_readl(addr);
107 			__raw_writel(0xffffffff ^ value, addr);
108 			break;
109 		default:
110 			BUG();
111 			break;
112 		}
113 	}
114 }
115 
116 static struct intc_handle_int *intc_find_irq(struct intc_handle_int *hp,
117 					     unsigned int nr_hp,
118 					     unsigned int irq)
119 {
120 	int i;
121 
122 	/*
123 	 * this doesn't scale well, but...
124 	 *
125 	 * this function should only be used for cerain uncommon
126 	 * operations such as intc_set_priority() and intc_set_type()
127 	 * and in those rare cases performance doesn't matter that much.
128 	 * keeping the memory footprint low is more important.
129 	 *
130 	 * one rather simple way to speed this up and still keep the
131 	 * memory footprint down is to make sure the array is sorted
132 	 * and then perform a bisect to lookup the irq.
133 	 */
134 	for (i = 0; i < nr_hp; i++) {
135 		if ((hp + i)->irq != irq)
136 			continue;
137 
138 		return hp + i;
139 	}
140 
141 	return NULL;
142 }
143 
144 int intc_set_priority(unsigned int irq, unsigned int prio)
145 {
146 	struct intc_desc_int *d = get_intc_desc(irq);
147 	struct intc_handle_int *ihp;
148 
149 	if (!intc_get_prio_level(irq) || prio <= 1)
150 		return -EINVAL;
151 
152 	ihp = intc_find_irq(d->prio, d->nr_prio, irq);
153 	if (ihp) {
154 		if (prio >= (1 << _INTC_WIDTH(ihp->handle)))
155 			return -EINVAL;
156 
157 		intc_set_prio_level(irq, prio);
158 
159 		/*
160 		 * only set secondary masking method directly
161 		 * primary masking method is using intc_prio_level[irq]
162 		 * priority level will be set during next enable()
163 		 */
164 		if (_INTC_FN(ihp->handle) != REG_FN_ERR)
165 			_intc_enable(irq, ihp->handle);
166 	}
167 	return 0;
168 }
169 
170 #define VALID(x) (x | 0x80)
171 
172 static unsigned char intc_irq_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
173 	[IRQ_TYPE_EDGE_FALLING] = VALID(0),
174 	[IRQ_TYPE_EDGE_RISING] = VALID(1),
175 	[IRQ_TYPE_LEVEL_LOW] = VALID(2),
176 	/* SH7706, SH7707 and SH7709 do not support high level triggered */
177 #if !defined(CONFIG_CPU_SUBTYPE_SH7706) && \
178     !defined(CONFIG_CPU_SUBTYPE_SH7707) && \
179     !defined(CONFIG_CPU_SUBTYPE_SH7709)
180 	[IRQ_TYPE_LEVEL_HIGH] = VALID(3),
181 #endif
182 };
183 
184 static int intc_set_type(unsigned int irq, unsigned int type)
185 {
186 	struct intc_desc_int *d = get_intc_desc(irq);
187 	unsigned char value = intc_irq_sense_table[type & IRQ_TYPE_SENSE_MASK];
188 	struct intc_handle_int *ihp;
189 	unsigned long addr;
190 
191 	if (!value)
192 		return -EINVAL;
193 
194 	ihp = intc_find_irq(d->sense, d->nr_sense, irq);
195 	if (ihp) {
196 		addr = INTC_REG(d, _INTC_ADDR_E(ihp->handle), 0);
197 		intc_reg_fns[_INTC_FN(ihp->handle)](addr, ihp->handle, value);
198 	}
199 
200 	return 0;
201 }
202 
203 struct irq_chip intc_irq_chip	= {
204 	.mask		= intc_disable,
205 	.unmask		= intc_enable,
206 	.mask_ack	= intc_mask_ack,
207 	.enable		= intc_enable,
208 	.disable	= intc_disable,
209 	.shutdown	= intc_disable,
210 	.set_type	= intc_set_type,
211 	.set_wake	= intc_set_wake,
212 #ifdef CONFIG_SMP
213 	.set_affinity	= intc_set_affinity,
214 #endif
215 };
216