1 /*
2 * SPEAr platform shared irq layer source file
3 *
4 * Copyright (C) 2009-2012 ST Microelectronics
5 * Viresh Kumar <vireshk@kernel.org>
6 *
7 * Copyright (C) 2012 ST Microelectronics
8 * Shiraz Hashim <shiraz.linux.kernel@gmail.com>
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 */
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16 #include <linux/err.h>
17 #include <linux/export.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/irq.h>
21 #include <linux/irqchip.h>
22 #include <linux/irqdomain.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25 #include <linux/of_irq.h>
26 #include <linux/spinlock.h>
27
28 /*
29 * struct spear_shirq: shared irq structure
30 *
31 * base: Base register address
32 * status_reg: Status register offset for chained interrupt handler
33 * mask_reg: Mask register offset for irq chip
34 * mask: Mask to apply to the status register
35 * virq_base: Base virtual interrupt number
36 * nr_irqs: Number of interrupts handled by this block
37 * offset: Bit offset of the first interrupt
38 * irq_chip: Interrupt controller chip used for this instance,
39 * if NULL group is disabled, but accounted
40 */
41 struct spear_shirq {
42 void __iomem *base;
43 u32 status_reg;
44 u32 mask_reg;
45 u32 mask;
46 u32 virq_base;
47 u32 nr_irqs;
48 u32 offset;
49 struct irq_chip *irq_chip;
50 };
51
52 /* spear300 shared irq registers offsets and masks */
53 #define SPEAR300_INT_ENB_MASK_REG 0x54
54 #define SPEAR300_INT_STS_MASK_REG 0x58
55
56 static DEFINE_RAW_SPINLOCK(shirq_lock);
57
shirq_irq_mask(struct irq_data * d)58 static void shirq_irq_mask(struct irq_data *d)
59 {
60 struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
61 u32 val, shift = d->irq - shirq->virq_base + shirq->offset;
62 u32 __iomem *reg = shirq->base + shirq->mask_reg;
63
64 raw_spin_lock(&shirq_lock);
65 val = readl(reg) & ~(0x1 << shift);
66 writel(val, reg);
67 raw_spin_unlock(&shirq_lock);
68 }
69
shirq_irq_unmask(struct irq_data * d)70 static void shirq_irq_unmask(struct irq_data *d)
71 {
72 struct spear_shirq *shirq = irq_data_get_irq_chip_data(d);
73 u32 val, shift = d->irq - shirq->virq_base + shirq->offset;
74 u32 __iomem *reg = shirq->base + shirq->mask_reg;
75
76 raw_spin_lock(&shirq_lock);
77 val = readl(reg) | (0x1 << shift);
78 writel(val, reg);
79 raw_spin_unlock(&shirq_lock);
80 }
81
82 static struct irq_chip shirq_chip = {
83 .name = "spear-shirq",
84 .irq_mask = shirq_irq_mask,
85 .irq_unmask = shirq_irq_unmask,
86 };
87
88 static struct spear_shirq spear300_shirq_ras1 = {
89 .offset = 0,
90 .nr_irqs = 9,
91 .mask = ((0x1 << 9) - 1) << 0,
92 .irq_chip = &shirq_chip,
93 .status_reg = SPEAR300_INT_STS_MASK_REG,
94 .mask_reg = SPEAR300_INT_ENB_MASK_REG,
95 };
96
97 static struct spear_shirq *spear300_shirq_blocks[] = {
98 &spear300_shirq_ras1,
99 };
100
101 /* spear310 shared irq registers offsets and masks */
102 #define SPEAR310_INT_STS_MASK_REG 0x04
103
104 static struct spear_shirq spear310_shirq_ras1 = {
105 .offset = 0,
106 .nr_irqs = 8,
107 .mask = ((0x1 << 8) - 1) << 0,
108 .irq_chip = &dummy_irq_chip,
109 .status_reg = SPEAR310_INT_STS_MASK_REG,
110 };
111
112 static struct spear_shirq spear310_shirq_ras2 = {
113 .offset = 8,
114 .nr_irqs = 5,
115 .mask = ((0x1 << 5) - 1) << 8,
116 .irq_chip = &dummy_irq_chip,
117 .status_reg = SPEAR310_INT_STS_MASK_REG,
118 };
119
120 static struct spear_shirq spear310_shirq_ras3 = {
121 .offset = 13,
122 .nr_irqs = 1,
123 .mask = ((0x1 << 1) - 1) << 13,
124 .irq_chip = &dummy_irq_chip,
125 .status_reg = SPEAR310_INT_STS_MASK_REG,
126 };
127
128 static struct spear_shirq spear310_shirq_intrcomm_ras = {
129 .offset = 14,
130 .nr_irqs = 3,
131 .mask = ((0x1 << 3) - 1) << 14,
132 .irq_chip = &dummy_irq_chip,
133 .status_reg = SPEAR310_INT_STS_MASK_REG,
134 };
135
136 static struct spear_shirq *spear310_shirq_blocks[] = {
137 &spear310_shirq_ras1,
138 &spear310_shirq_ras2,
139 &spear310_shirq_ras3,
140 &spear310_shirq_intrcomm_ras,
141 };
142
143 /* spear320 shared irq registers offsets and masks */
144 #define SPEAR320_INT_STS_MASK_REG 0x04
145 #define SPEAR320_INT_CLR_MASK_REG 0x04
146 #define SPEAR320_INT_ENB_MASK_REG 0x08
147
148 static struct spear_shirq spear320_shirq_ras3 = {
149 .offset = 0,
150 .nr_irqs = 7,
151 .mask = ((0x1 << 7) - 1) << 0,
152 .irq_chip = &dummy_irq_chip,
153 .status_reg = SPEAR320_INT_STS_MASK_REG,
154 };
155
156 static struct spear_shirq spear320_shirq_ras1 = {
157 .offset = 7,
158 .nr_irqs = 3,
159 .mask = ((0x1 << 3) - 1) << 7,
160 .irq_chip = &dummy_irq_chip,
161 .status_reg = SPEAR320_INT_STS_MASK_REG,
162 };
163
164 static struct spear_shirq spear320_shirq_ras2 = {
165 .offset = 10,
166 .nr_irqs = 1,
167 .mask = ((0x1 << 1) - 1) << 10,
168 .irq_chip = &dummy_irq_chip,
169 .status_reg = SPEAR320_INT_STS_MASK_REG,
170 };
171
172 static struct spear_shirq spear320_shirq_intrcomm_ras = {
173 .offset = 11,
174 .nr_irqs = 11,
175 .mask = ((0x1 << 11) - 1) << 11,
176 .irq_chip = &dummy_irq_chip,
177 .status_reg = SPEAR320_INT_STS_MASK_REG,
178 };
179
180 static struct spear_shirq *spear320_shirq_blocks[] = {
181 &spear320_shirq_ras3,
182 &spear320_shirq_ras1,
183 &spear320_shirq_ras2,
184 &spear320_shirq_intrcomm_ras,
185 };
186
shirq_handler(struct irq_desc * desc)187 static void shirq_handler(struct irq_desc *desc)
188 {
189 struct spear_shirq *shirq = irq_desc_get_handler_data(desc);
190 u32 pend;
191
192 pend = readl(shirq->base + shirq->status_reg) & shirq->mask;
193 pend >>= shirq->offset;
194
195 while (pend) {
196 int irq = __ffs(pend);
197
198 pend &= ~(0x1 << irq);
199 generic_handle_irq(shirq->virq_base + irq);
200 }
201 }
202
spear_shirq_register(struct spear_shirq * shirq,int parent_irq)203 static void __init spear_shirq_register(struct spear_shirq *shirq,
204 int parent_irq)
205 {
206 int i;
207
208 if (!shirq->irq_chip)
209 return;
210
211 irq_set_chained_handler_and_data(parent_irq, shirq_handler, shirq);
212
213 for (i = 0; i < shirq->nr_irqs; i++) {
214 irq_set_chip_and_handler(shirq->virq_base + i,
215 shirq->irq_chip, handle_simple_irq);
216 irq_set_chip_data(shirq->virq_base + i, shirq);
217 }
218 }
219
shirq_init(struct spear_shirq ** shirq_blocks,int block_nr,struct device_node * np)220 static int __init shirq_init(struct spear_shirq **shirq_blocks, int block_nr,
221 struct device_node *np)
222 {
223 int i, parent_irq, virq_base, hwirq = 0, nr_irqs = 0;
224 struct irq_domain *shirq_domain;
225 void __iomem *base;
226
227 base = of_iomap(np, 0);
228 if (!base) {
229 pr_err("%s: failed to map shirq registers\n", __func__);
230 return -ENXIO;
231 }
232
233 for (i = 0; i < block_nr; i++)
234 nr_irqs += shirq_blocks[i]->nr_irqs;
235
236 virq_base = irq_alloc_descs(-1, 0, nr_irqs, 0);
237 if (virq_base < 0) {
238 pr_err("%s: irq desc alloc failed\n", __func__);
239 goto err_unmap;
240 }
241
242 shirq_domain = irq_domain_add_legacy(np, nr_irqs, virq_base, 0,
243 &irq_domain_simple_ops, NULL);
244 if (WARN_ON(!shirq_domain)) {
245 pr_warn("%s: irq domain init failed\n", __func__);
246 goto err_free_desc;
247 }
248
249 for (i = 0; i < block_nr; i++) {
250 shirq_blocks[i]->base = base;
251 shirq_blocks[i]->virq_base = irq_find_mapping(shirq_domain,
252 hwirq);
253
254 parent_irq = irq_of_parse_and_map(np, i);
255 spear_shirq_register(shirq_blocks[i], parent_irq);
256 hwirq += shirq_blocks[i]->nr_irqs;
257 }
258
259 return 0;
260
261 err_free_desc:
262 irq_free_descs(virq_base, nr_irqs);
263 err_unmap:
264 iounmap(base);
265 return -ENXIO;
266 }
267
spear300_shirq_of_init(struct device_node * np,struct device_node * parent)268 static int __init spear300_shirq_of_init(struct device_node *np,
269 struct device_node *parent)
270 {
271 return shirq_init(spear300_shirq_blocks,
272 ARRAY_SIZE(spear300_shirq_blocks), np);
273 }
274 IRQCHIP_DECLARE(spear300_shirq, "st,spear300-shirq", spear300_shirq_of_init);
275
spear310_shirq_of_init(struct device_node * np,struct device_node * parent)276 static int __init spear310_shirq_of_init(struct device_node *np,
277 struct device_node *parent)
278 {
279 return shirq_init(spear310_shirq_blocks,
280 ARRAY_SIZE(spear310_shirq_blocks), np);
281 }
282 IRQCHIP_DECLARE(spear310_shirq, "st,spear310-shirq", spear310_shirq_of_init);
283
spear320_shirq_of_init(struct device_node * np,struct device_node * parent)284 static int __init spear320_shirq_of_init(struct device_node *np,
285 struct device_node *parent)
286 {
287 return shirq_init(spear320_shirq_blocks,
288 ARRAY_SIZE(spear320_shirq_blocks), np);
289 }
290 IRQCHIP_DECLARE(spear320_shirq, "st,spear320-shirq", spear320_shirq_of_init);
291