xref: /linux/drivers/sh/intc/chip.c (revision 765532c8aaac624b5f8687af6d319c6a1138a257)
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(struct irq_data *data, unsigned long handle)
16 {
17 	unsigned int irq = data->irq;
18 	struct intc_desc_int *d = get_intc_desc(irq);
19 	unsigned long addr;
20 	unsigned int cpu;
21 
22 	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_E(handle)); cpu++) {
23 #ifdef CONFIG_SMP
24 		if (!cpumask_test_cpu(cpu, data->affinity))
25 			continue;
26 #endif
27 		addr = INTC_REG(d, _INTC_ADDR_E(handle), cpu);
28 		intc_enable_fns[_INTC_MODE(handle)](addr, handle, intc_reg_fns\
29 						    [_INTC_FN(handle)], irq);
30 	}
31 
32 	intc_balancing_enable(irq);
33 }
34 
35 static void intc_enable(struct irq_data *data)
36 {
37 	_intc_enable(data, (unsigned long)irq_data_get_irq_chip_data(data));
38 }
39 
40 static void intc_disable(struct irq_data *data)
41 {
42 	unsigned int irq = data->irq;
43 	struct intc_desc_int *d = get_intc_desc(irq);
44 	unsigned long handle = (unsigned long)irq_data_get_irq_chip_data(data);
45 	unsigned long addr;
46 	unsigned int cpu;
47 
48 	intc_balancing_disable(irq);
49 
50 	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_D(handle)); cpu++) {
51 #ifdef CONFIG_SMP
52 		if (!cpumask_test_cpu(cpu, data->affinity))
53 			continue;
54 #endif
55 		addr = INTC_REG(d, _INTC_ADDR_D(handle), cpu);
56 		intc_disable_fns[_INTC_MODE(handle)](addr, handle,intc_reg_fns\
57 						     [_INTC_FN(handle)], irq);
58 	}
59 }
60 
61 static int intc_set_wake(struct irq_data *data, unsigned int on)
62 {
63 	return 0; /* allow wakeup, but setup hardware in intc_suspend() */
64 }
65 
66 #ifdef CONFIG_SMP
67 /*
68  * This is held with the irq desc lock held, so we don't require any
69  * additional locking here at the intc desc level. The affinity mask is
70  * later tested in the enable/disable paths.
71  */
72 static int intc_set_affinity(struct irq_data *data,
73 			     const struct cpumask *cpumask,
74 			     bool force)
75 {
76 	if (!cpumask_intersects(cpumask, cpu_online_mask))
77 		return -1;
78 
79 	cpumask_copy(data->affinity, cpumask);
80 
81 	return 0;
82 }
83 #endif
84 
85 static void intc_mask_ack(struct irq_data *data)
86 {
87 	unsigned int irq = data->irq;
88 	struct intc_desc_int *d = get_intc_desc(irq);
89 	unsigned long handle = intc_get_ack_handle(irq);
90 	unsigned long addr;
91 
92 	intc_disable(data);
93 
94 	/* read register and write zero only to the associated bit */
95 	if (handle) {
96 		unsigned int value;
97 
98 		addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
99 		value = intc_set_field_from_handle(0, 1, handle);
100 
101 		switch (_INTC_FN(handle)) {
102 		case REG_FN_MODIFY_BASE + 0:	/* 8bit */
103 			__raw_readb(addr);
104 			__raw_writeb(0xff ^ value, addr);
105 			break;
106 		case REG_FN_MODIFY_BASE + 1:	/* 16bit */
107 			__raw_readw(addr);
108 			__raw_writew(0xffff ^ value, addr);
109 			break;
110 		case REG_FN_MODIFY_BASE + 3:	/* 32bit */
111 			__raw_readl(addr);
112 			__raw_writel(0xffffffff ^ value, addr);
113 			break;
114 		default:
115 			BUG();
116 			break;
117 		}
118 	}
119 }
120 
121 static struct intc_handle_int *intc_find_irq(struct intc_handle_int *hp,
122 					     unsigned int nr_hp,
123 					     unsigned int irq)
124 {
125 	int i;
126 
127 	/*
128 	 * this doesn't scale well, but...
129 	 *
130 	 * this function should only be used for cerain uncommon
131 	 * operations such as intc_set_priority() and intc_set_type()
132 	 * and in those rare cases performance doesn't matter that much.
133 	 * keeping the memory footprint low is more important.
134 	 *
135 	 * one rather simple way to speed this up and still keep the
136 	 * memory footprint down is to make sure the array is sorted
137 	 * and then perform a bisect to lookup the irq.
138 	 */
139 	for (i = 0; i < nr_hp; i++) {
140 		if ((hp + i)->irq != irq)
141 			continue;
142 
143 		return hp + i;
144 	}
145 
146 	return NULL;
147 }
148 
149 int intc_set_priority(unsigned int irq, unsigned int prio)
150 {
151 	struct intc_desc_int *d = get_intc_desc(irq);
152 	struct irq_data *data = irq_get_irq_data(irq);
153 	struct intc_handle_int *ihp;
154 
155 	if (!intc_get_prio_level(irq) || prio <= 1)
156 		return -EINVAL;
157 
158 	ihp = intc_find_irq(d->prio, d->nr_prio, irq);
159 	if (ihp) {
160 		if (prio >= (1 << _INTC_WIDTH(ihp->handle)))
161 			return -EINVAL;
162 
163 		intc_set_prio_level(irq, prio);
164 
165 		/*
166 		 * only set secondary masking method directly
167 		 * primary masking method is using intc_prio_level[irq]
168 		 * priority level will be set during next enable()
169 		 */
170 		if (_INTC_FN(ihp->handle) != REG_FN_ERR)
171 			_intc_enable(data, ihp->handle);
172 	}
173 	return 0;
174 }
175 
176 #define VALID(x) (x | 0x80)
177 
178 static unsigned char intc_irq_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
179 	[IRQ_TYPE_EDGE_FALLING] = VALID(0),
180 	[IRQ_TYPE_EDGE_RISING] = VALID(1),
181 	[IRQ_TYPE_LEVEL_LOW] = VALID(2),
182 	/* SH7706, SH7707 and SH7709 do not support high level triggered */
183 #if !defined(CONFIG_CPU_SUBTYPE_SH7706) && \
184     !defined(CONFIG_CPU_SUBTYPE_SH7707) && \
185     !defined(CONFIG_CPU_SUBTYPE_SH7709)
186 	[IRQ_TYPE_LEVEL_HIGH] = VALID(3),
187 #endif
188 };
189 
190 static int intc_set_type(struct irq_data *data, unsigned int type)
191 {
192 	unsigned int irq = data->irq;
193 	struct intc_desc_int *d = get_intc_desc(irq);
194 	unsigned char value = intc_irq_sense_table[type & IRQ_TYPE_SENSE_MASK];
195 	struct intc_handle_int *ihp;
196 	unsigned long addr;
197 
198 	if (!value)
199 		return -EINVAL;
200 
201 	ihp = intc_find_irq(d->sense, d->nr_sense, irq);
202 	if (ihp) {
203 		addr = INTC_REG(d, _INTC_ADDR_E(ihp->handle), 0);
204 		intc_reg_fns[_INTC_FN(ihp->handle)](addr, ihp->handle, value);
205 	}
206 
207 	return 0;
208 }
209 
210 struct irq_chip intc_irq_chip	= {
211 	.irq_mask		= intc_disable,
212 	.irq_unmask		= intc_enable,
213 	.irq_mask_ack		= intc_mask_ack,
214 	.irq_enable		= intc_enable,
215 	.irq_disable		= intc_disable,
216 	.irq_shutdown		= intc_disable,
217 	.irq_set_type		= intc_set_type,
218 	.irq_set_wake		= intc_set_wake,
219 #ifdef CONFIG_SMP
220 	.irq_set_affinity	= intc_set_affinity,
221 #endif
222 };
223