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9#define DRV_MODULE_NAME "flipper-pic"
10#define pr_fmt(fmt) DRV_MODULE_NAME ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/irq.h>
15#include <linux/irqdomain.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <asm/io.h>
19
20#include "flipper-pic.h"
21
22#define FLIPPER_NR_IRQS 32
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32
33#define FLIPPER_ICR 0x00
34#define FLIPPER_ICR_RSS (1<<16)
35
36#define FLIPPER_IMR 0x04
37
38#define FLIPPER_RESET 0x24
39
40
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43
44
45
46static void flipper_pic_mask_and_ack(struct irq_data *d)
47{
48 int irq = irqd_to_hwirq(d);
49 void __iomem *io_base = irq_data_get_irq_chip_data(d);
50 u32 mask = 1 << irq;
51
52 clrbits32(io_base + FLIPPER_IMR, mask);
53
54 out_be32(io_base + FLIPPER_ICR, mask);
55}
56
57static void flipper_pic_ack(struct irq_data *d)
58{
59 int irq = irqd_to_hwirq(d);
60 void __iomem *io_base = irq_data_get_irq_chip_data(d);
61
62
63 out_be32(io_base + FLIPPER_ICR, 1 << irq);
64}
65
66static void flipper_pic_mask(struct irq_data *d)
67{
68 int irq = irqd_to_hwirq(d);
69 void __iomem *io_base = irq_data_get_irq_chip_data(d);
70
71 clrbits32(io_base + FLIPPER_IMR, 1 << irq);
72}
73
74static void flipper_pic_unmask(struct irq_data *d)
75{
76 int irq = irqd_to_hwirq(d);
77 void __iomem *io_base = irq_data_get_irq_chip_data(d);
78
79 setbits32(io_base + FLIPPER_IMR, 1 << irq);
80}
81
82
83static struct irq_chip flipper_pic = {
84 .name = "flipper-pic",
85 .irq_ack = flipper_pic_ack,
86 .irq_mask_ack = flipper_pic_mask_and_ack,
87 .irq_mask = flipper_pic_mask,
88 .irq_unmask = flipper_pic_unmask,
89};
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95
96static struct irq_domain *flipper_irq_host;
97
98static int flipper_pic_map(struct irq_domain *h, unsigned int virq,
99 irq_hw_number_t hwirq)
100{
101 irq_set_chip_data(virq, h->host_data);
102 irq_set_status_flags(virq, IRQ_LEVEL);
103 irq_set_chip_and_handler(virq, &flipper_pic, handle_level_irq);
104 return 0;
105}
106
107static const struct irq_domain_ops flipper_irq_domain_ops = {
108 .map = flipper_pic_map,
109};
110
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114
115
116static void __flipper_quiesce(void __iomem *io_base)
117{
118
119 out_be32(io_base + FLIPPER_IMR, 0x00000000);
120 out_be32(io_base + FLIPPER_ICR, 0xffffffff);
121}
122
123static struct irq_domain * __init flipper_pic_init(struct device_node *np)
124{
125 struct device_node *pi;
126 struct irq_domain *irq_domain = NULL;
127 struct resource res;
128 void __iomem *io_base;
129 int retval;
130
131 pi = of_get_parent(np);
132 if (!pi) {
133 pr_err("no parent found\n");
134 goto out;
135 }
136 if (!of_device_is_compatible(pi, "nintendo,flipper-pi")) {
137 pr_err("unexpected parent compatible\n");
138 goto out;
139 }
140
141 retval = of_address_to_resource(pi, 0, &res);
142 if (retval) {
143 pr_err("no io memory range found\n");
144 goto out;
145 }
146 io_base = ioremap(res.start, resource_size(&res));
147
148 pr_info("controller at 0x%08x mapped to 0x%p\n", res.start, io_base);
149
150 __flipper_quiesce(io_base);
151
152 irq_domain = irq_domain_add_linear(np, FLIPPER_NR_IRQS,
153 &flipper_irq_domain_ops, io_base);
154 if (!irq_domain) {
155 pr_err("failed to allocate irq_domain\n");
156 return NULL;
157 }
158
159out:
160 return irq_domain;
161}
162
163unsigned int flipper_pic_get_irq(void)
164{
165 void __iomem *io_base = flipper_irq_host->host_data;
166 int irq;
167 u32 irq_status;
168
169 irq_status = in_be32(io_base + FLIPPER_ICR) &
170 in_be32(io_base + FLIPPER_IMR);
171 if (irq_status == 0)
172 return 0;
173
174 irq = __ffs(irq_status);
175 return irq_linear_revmap(flipper_irq_host, irq);
176}
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182
183void __init flipper_pic_probe(void)
184{
185 struct device_node *np;
186
187 np = of_find_compatible_node(NULL, NULL, "nintendo,flipper-pic");
188 BUG_ON(!np);
189
190 flipper_irq_host = flipper_pic_init(np);
191 BUG_ON(!flipper_irq_host);
192
193 irq_set_default_host(flipper_irq_host);
194
195 of_node_put(np);
196}
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208
209void flipper_quiesce(void)
210{
211 void __iomem *io_base = flipper_irq_host->host_data;
212
213 __flipper_quiesce(io_base);
214}
215
216
217
218
219void flipper_platform_reset(void)
220{
221 void __iomem *io_base;
222
223 if (flipper_irq_host && flipper_irq_host->host_data) {
224 io_base = flipper_irq_host->host_data;
225 out_8(io_base + FLIPPER_RESET, 0x00);
226 }
227}
228
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230
231
232int flipper_is_reset_button_pressed(void)
233{
234 void __iomem *io_base;
235 u32 icr;
236
237 if (flipper_irq_host && flipper_irq_host->host_data) {
238 io_base = flipper_irq_host->host_data;
239 icr = in_be32(io_base + FLIPPER_ICR);
240 return !(icr & FLIPPER_ICR_RSS);
241 }
242 return 0;
243}
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245