xref: /openbmc/linux/drivers/sh/intc/chip.c (revision 30377642138aadeef35a31c2f90dba0b6fa7b91a)
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 #ifdef CONFIG_SMP
62 /*
63  * This is held with the irq desc lock held, so we don't require any
64  * additional locking here at the intc desc level. The affinity mask is
65  * later tested in the enable/disable paths.
66  */
67 static int intc_set_affinity(struct irq_data *data,
68 			     const struct cpumask *cpumask,
69 			     bool force)
70 {
71 	if (!cpumask_intersects(cpumask, cpu_online_mask))
72 		return -1;
73 
74 	cpumask_copy(data->affinity, cpumask);
75 
76 	return IRQ_SET_MASK_OK_NOCOPY;
77 }
78 #endif
79 
80 static void intc_mask_ack(struct irq_data *data)
81 {
82 	unsigned int irq = data->irq;
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(data);
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 irq_data *data = irq_get_irq_data(irq);
148 	struct intc_handle_int *ihp;
149 
150 	if (!intc_get_prio_level(irq) || prio <= 1)
151 		return -EINVAL;
152 
153 	ihp = intc_find_irq(d->prio, d->nr_prio, irq);
154 	if (ihp) {
155 		if (prio >= (1 << _INTC_WIDTH(ihp->handle)))
156 			return -EINVAL;
157 
158 		intc_set_prio_level(irq, prio);
159 
160 		/*
161 		 * only set secondary masking method directly
162 		 * primary masking method is using intc_prio_level[irq]
163 		 * priority level will be set during next enable()
164 		 */
165 		if (_INTC_FN(ihp->handle) != REG_FN_ERR)
166 			_intc_enable(data, ihp->handle);
167 	}
168 	return 0;
169 }
170 
171 #define SENSE_VALID_FLAG 0x80
172 #define VALID(x) (x | SENSE_VALID_FLAG)
173 
174 static unsigned char intc_irq_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
175 	[IRQ_TYPE_EDGE_FALLING] = VALID(0),
176 	[IRQ_TYPE_EDGE_RISING] = VALID(1),
177 	[IRQ_TYPE_LEVEL_LOW] = VALID(2),
178 	/* SH7706, SH7707 and SH7709 do not support high level triggered */
179 #if !defined(CONFIG_CPU_SUBTYPE_SH7706) && \
180     !defined(CONFIG_CPU_SUBTYPE_SH7707) && \
181     !defined(CONFIG_CPU_SUBTYPE_SH7709)
182 	[IRQ_TYPE_LEVEL_HIGH] = VALID(3),
183 #endif
184 #if defined(CONFIG_ARM) /* all recent SH-Mobile / R-Mobile ARM support this */
185 	[IRQ_TYPE_EDGE_BOTH] = VALID(4),
186 #endif
187 };
188 
189 static int intc_set_type(struct irq_data *data, unsigned int type)
190 {
191 	unsigned int irq = data->irq;
192 	struct intc_desc_int *d = get_intc_desc(irq);
193 	unsigned char value = intc_irq_sense_table[type & IRQ_TYPE_SENSE_MASK];
194 	struct intc_handle_int *ihp;
195 	unsigned long addr;
196 
197 	if (!value)
198 		return -EINVAL;
199 
200 	value &= ~SENSE_VALID_FLAG;
201 
202 	ihp = intc_find_irq(d->sense, d->nr_sense, irq);
203 	if (ihp) {
204 		/* PINT has 2-bit sense registers, should fail on EDGE_BOTH */
205 		if (value >= (1 << _INTC_WIDTH(ihp->handle)))
206 			return -EINVAL;
207 
208 		addr = INTC_REG(d, _INTC_ADDR_E(ihp->handle), 0);
209 		intc_reg_fns[_INTC_FN(ihp->handle)](addr, ihp->handle, value);
210 	}
211 
212 	return 0;
213 }
214 
215 struct irq_chip intc_irq_chip	= {
216 	.irq_mask		= intc_disable,
217 	.irq_unmask		= intc_enable,
218 	.irq_mask_ack		= intc_mask_ack,
219 	.irq_enable		= intc_enable,
220 	.irq_disable		= intc_disable,
221 	.irq_set_type		= intc_set_type,
222 #ifdef CONFIG_SMP
223 	.irq_set_affinity	= intc_set_affinity,
224 #endif
225 	.flags			= IRQCHIP_SKIP_SET_WAKE,
226 };
227