1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3
4#include <linux/kernel.h>
5#include <linux/init.h>
6#include <linux/of.h>
7#include <linux/of_address.h>
8#include <linux/module.h>
9#include <linux/irqdomain.h>
10#include <linux/irqchip.h>
11#include <linux/irq.h>
12#include <linux/interrupt.h>
13#include <linux/io.h>
14#include <asm/irq.h>
15
16#define INTC_IRQS 64
17
18#define CK_INTC_ICR 0x00
19#define CK_INTC_PEN31_00 0x14
20#define CK_INTC_PEN63_32 0x2c
21#define CK_INTC_NEN31_00 0x10
22#define CK_INTC_NEN63_32 0x28
23#define CK_INTC_SOURCE 0x40
24#define CK_INTC_DUAL_BASE 0x100
25
26#define GX_INTC_PEN31_00 0x00
27#define GX_INTC_PEN63_32 0x04
28#define GX_INTC_NEN31_00 0x40
29#define GX_INTC_NEN63_32 0x44
30#define GX_INTC_NMASK31_00 0x50
31#define GX_INTC_NMASK63_32 0x54
32#define GX_INTC_SOURCE 0x60
33
34static void __iomem *reg_base;
35static struct irq_domain *root_domain;
36
37static int nr_irq = INTC_IRQS;
38
39/*
40 * When controller support pulse signal, the PEN_reg will hold on signal
41 * without software trigger.
42 *
43 * So, to support pulse signal we need to clear IFR_reg and the address of
44 * IFR_offset is NEN_offset - 8.
45 */
46static void irq_ck_mask_set_bit(struct irq_data *d)
47{
48 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
49 struct irq_chip_type *ct = irq_data_get_chip_type(d);
50 unsigned long ifr = ct->regs.mask - 8;
51 u32 mask = d->mask;
52
53 irq_gc_lock(gc);
54 *ct->mask_cache |= mask;
55 irq_reg_writel(gc, val: *ct->mask_cache, reg_offset: ct->regs.mask);
56 irq_reg_writel(gc, val: irq_reg_readl(gc, reg_offset: ifr) & ~mask, reg_offset: ifr);
57 irq_gc_unlock(gc);
58}
59
60static void __init ck_set_gc(struct device_node *node, void __iomem *reg_base,
61 u32 mask_reg, u32 irq_base)
62{
63 struct irq_chip_generic *gc;
64
65 gc = irq_get_domain_generic_chip(d: root_domain, hw_irq: irq_base);
66 gc->reg_base = reg_base;
67 gc->chip_types[0].regs.mask = mask_reg;
68 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
69 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
70
71 if (of_property_read_bool(np: node, propname: "csky,support-pulse-signal"))
72 gc->chip_types[0].chip.irq_unmask = irq_ck_mask_set_bit;
73}
74
75static inline u32 build_channel_val(u32 idx, u32 magic)
76{
77 u32 res;
78
79 /*
80 * Set the same index for each channel
81 */
82 res = idx | (idx << 8) | (idx << 16) | (idx << 24);
83
84 /*
85 * Set the channel magic number in descending order.
86 * The magic is 0x00010203 for ck-intc
87 * The magic is 0x03020100 for gx6605s-intc
88 */
89 return res | magic;
90}
91
92static inline void setup_irq_channel(u32 magic, void __iomem *reg_addr)
93{
94 u32 i;
95
96 /* Setup 64 channel slots */
97 for (i = 0; i < INTC_IRQS; i += 4)
98 writel(val: build_channel_val(idx: i, magic), addr: reg_addr + i);
99}
100
101static int __init
102ck_intc_init_comm(struct device_node *node, struct device_node *parent)
103{
104 int ret;
105
106 if (parent) {
107 pr_err("C-SKY Intc not a root irq controller\n");
108 return -EINVAL;
109 }
110
111 reg_base = of_iomap(node, index: 0);
112 if (!reg_base) {
113 pr_err("C-SKY Intc unable to map: %p.\n", node);
114 return -EINVAL;
115 }
116
117 root_domain = irq_domain_add_linear(of_node: node, size: nr_irq,
118 ops: &irq_generic_chip_ops, NULL);
119 if (!root_domain) {
120 pr_err("C-SKY Intc irq_domain_add failed.\n");
121 return -ENOMEM;
122 }
123
124 ret = irq_alloc_domain_generic_chips(root_domain, 32, 1,
125 "csky_intc", handle_level_irq,
126 IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN, 0, 0);
127 if (ret) {
128 pr_err("C-SKY Intc irq_alloc_gc failed.\n");
129 return -ENOMEM;
130 }
131
132 return 0;
133}
134
135static inline bool handle_irq_perbit(struct pt_regs *regs, u32 hwirq,
136 u32 irq_base)
137{
138 if (hwirq == 0)
139 return false;
140
141 generic_handle_domain_irq(domain: root_domain, hwirq: irq_base + __fls(word: hwirq));
142
143 return true;
144}
145
146/* gx6605s 64 irqs interrupt controller */
147static void gx_irq_handler(struct pt_regs *regs)
148{
149 bool ret;
150
151retry:
152 ret = handle_irq_perbit(regs,
153 readl(addr: reg_base + GX_INTC_PEN63_32), irq_base: 32);
154 if (ret)
155 goto retry;
156
157 ret = handle_irq_perbit(regs,
158 readl(addr: reg_base + GX_INTC_PEN31_00), irq_base: 0);
159 if (ret)
160 goto retry;
161}
162
163static int __init
164gx_intc_init(struct device_node *node, struct device_node *parent)
165{
166 int ret;
167
168 ret = ck_intc_init_comm(node, parent);
169 if (ret)
170 return ret;
171
172 /*
173 * Initial enable reg to disable all interrupts
174 */
175 writel(val: 0x0, addr: reg_base + GX_INTC_NEN31_00);
176 writel(val: 0x0, addr: reg_base + GX_INTC_NEN63_32);
177
178 /*
179 * Initial mask reg with all unmasked, because we only use enable reg
180 */
181 writel(val: 0x0, addr: reg_base + GX_INTC_NMASK31_00);
182 writel(val: 0x0, addr: reg_base + GX_INTC_NMASK63_32);
183
184 setup_irq_channel(magic: 0x03020100, reg_addr: reg_base + GX_INTC_SOURCE);
185
186 ck_set_gc(node, reg_base, GX_INTC_NEN31_00, irq_base: 0);
187 ck_set_gc(node, reg_base, GX_INTC_NEN63_32, irq_base: 32);
188
189 set_handle_irq(gx_irq_handler);
190
191 return 0;
192}
193IRQCHIP_DECLARE(csky_gx6605s_intc, "csky,gx6605s-intc", gx_intc_init);
194
195/*
196 * C-SKY simple 64 irqs interrupt controller, dual-together could support 128
197 * irqs.
198 */
199static void ck_irq_handler(struct pt_regs *regs)
200{
201 bool ret;
202 void __iomem *reg_pen_lo = reg_base + CK_INTC_PEN31_00;
203 void __iomem *reg_pen_hi = reg_base + CK_INTC_PEN63_32;
204
205retry:
206 /* handle 0 - 63 irqs */
207 ret = handle_irq_perbit(regs, readl(addr: reg_pen_hi), irq_base: 32);
208 if (ret)
209 goto retry;
210
211 ret = handle_irq_perbit(regs, readl(addr: reg_pen_lo), irq_base: 0);
212 if (ret)
213 goto retry;
214
215 if (nr_irq == INTC_IRQS)
216 return;
217
218 /* handle 64 - 127 irqs */
219 ret = handle_irq_perbit(regs,
220 readl(addr: reg_pen_hi + CK_INTC_DUAL_BASE), irq_base: 96);
221 if (ret)
222 goto retry;
223
224 ret = handle_irq_perbit(regs,
225 readl(addr: reg_pen_lo + CK_INTC_DUAL_BASE), irq_base: 64);
226 if (ret)
227 goto retry;
228}
229
230static int __init
231ck_intc_init(struct device_node *node, struct device_node *parent)
232{
233 int ret;
234
235 ret = ck_intc_init_comm(node, parent);
236 if (ret)
237 return ret;
238
239 /* Initial enable reg to disable all interrupts */
240 writel(val: 0, addr: reg_base + CK_INTC_NEN31_00);
241 writel(val: 0, addr: reg_base + CK_INTC_NEN63_32);
242
243 /* Enable irq intc */
244 writel(BIT(31), addr: reg_base + CK_INTC_ICR);
245
246 ck_set_gc(node, reg_base, CK_INTC_NEN31_00, irq_base: 0);
247 ck_set_gc(node, reg_base, CK_INTC_NEN63_32, irq_base: 32);
248
249 setup_irq_channel(magic: 0x00010203, reg_addr: reg_base + CK_INTC_SOURCE);
250
251 set_handle_irq(ck_irq_handler);
252
253 return 0;
254}
255IRQCHIP_DECLARE(ck_intc, "csky,apb-intc", ck_intc_init);
256
257static int __init
258ck_dual_intc_init(struct device_node *node, struct device_node *parent)
259{
260 int ret;
261
262 /* dual-apb-intc up to 128 irq sources*/
263 nr_irq = INTC_IRQS * 2;
264
265 ret = ck_intc_init(node, parent);
266 if (ret)
267 return ret;
268
269 /* Initial enable reg to disable all interrupts */
270 writel(val: 0, addr: reg_base + CK_INTC_NEN31_00 + CK_INTC_DUAL_BASE);
271 writel(val: 0, addr: reg_base + CK_INTC_NEN63_32 + CK_INTC_DUAL_BASE);
272
273 ck_set_gc(node, reg_base: reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN31_00, irq_base: 64);
274 ck_set_gc(node, reg_base: reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN63_32, irq_base: 96);
275
276 setup_irq_channel(magic: 0x00010203,
277 reg_addr: reg_base + CK_INTC_SOURCE + CK_INTC_DUAL_BASE);
278
279 return 0;
280}
281IRQCHIP_DECLARE(ck_dual_intc, "csky,dual-apb-intc", ck_dual_intc_init);
282

source code of linux/drivers/irqchip/irq-csky-apb-intc.c