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
34 static void __iomem *reg_base;
35 static struct irq_domain *root_domain;
36
37 static 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 */
irq_ck_mask_set_bit(struct irq_data * d)46 static 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, *ct->mask_cache, ct->regs.mask);
56 irq_reg_writel(gc, irq_reg_readl(gc, ifr) & ~mask, ifr);
57 irq_gc_unlock(gc);
58 }
59
ck_set_gc(struct device_node * node,void __iomem * reg_base,u32 mask_reg,u32 irq_base)60 static 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(root_domain, 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_find_property(node, "csky,support-pulse-signal", NULL))
72 gc->chip_types[0].chip.irq_unmask = irq_ck_mask_set_bit;
73 }
74
build_channel_val(u32 idx,u32 magic)75 static 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
setup_irq_channel(u32 magic,void __iomem * reg_addr)92 static 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(build_channel_val(i, magic), reg_addr + i);
99 }
100
101 static int __init
ck_intc_init_comm(struct device_node * node,struct device_node * parent)102 ck_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, 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(node, nr_irq,
118 &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
handle_irq_perbit(struct pt_regs * regs,u32 hwirq,u32 irq_base)135 static inline bool handle_irq_perbit(struct pt_regs *regs, u32 hwirq,
136 u32 irq_base)
137 {
138 if (hwirq == 0)
139 return 0;
140
141 handle_domain_irq(root_domain, irq_base + __fls(hwirq), regs);
142
143 return 1;
144 }
145
146 /* gx6605s 64 irqs interrupt controller */
gx_irq_handler(struct pt_regs * regs)147 static void gx_irq_handler(struct pt_regs *regs)
148 {
149 bool ret;
150
151 retry:
152 ret = handle_irq_perbit(regs,
153 readl(reg_base + GX_INTC_PEN63_32), 32);
154 if (ret)
155 goto retry;
156
157 ret = handle_irq_perbit(regs,
158 readl(reg_base + GX_INTC_PEN31_00), 0);
159 if (ret)
160 goto retry;
161 }
162
163 static int __init
gx_intc_init(struct device_node * node,struct device_node * parent)164 gx_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(0x0, reg_base + GX_INTC_NEN31_00);
176 writel(0x0, reg_base + GX_INTC_NEN63_32);
177
178 /*
179 * Initial mask reg with all unmasked, because we only use enable reg
180 */
181 writel(0x0, reg_base + GX_INTC_NMASK31_00);
182 writel(0x0, reg_base + GX_INTC_NMASK63_32);
183
184 setup_irq_channel(0x03020100, reg_base + GX_INTC_SOURCE);
185
186 ck_set_gc(node, reg_base, GX_INTC_NEN31_00, 0);
187 ck_set_gc(node, reg_base, GX_INTC_NEN63_32, 32);
188
189 set_handle_irq(gx_irq_handler);
190
191 return 0;
192 }
193 IRQCHIP_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 */
ck_irq_handler(struct pt_regs * regs)199 static 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
205 retry:
206 /* handle 0 - 63 irqs */
207 ret = handle_irq_perbit(regs, readl(reg_pen_hi), 32);
208 if (ret)
209 goto retry;
210
211 ret = handle_irq_perbit(regs, readl(reg_pen_lo), 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(reg_pen_hi + CK_INTC_DUAL_BASE), 96);
221 if (ret)
222 goto retry;
223
224 ret = handle_irq_perbit(regs,
225 readl(reg_pen_lo + CK_INTC_DUAL_BASE), 64);
226 if (ret)
227 goto retry;
228 }
229
230 static int __init
ck_intc_init(struct device_node * node,struct device_node * parent)231 ck_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(0, reg_base + CK_INTC_NEN31_00);
241 writel(0, reg_base + CK_INTC_NEN63_32);
242
243 /* Enable irq intc */
244 writel(BIT(31), reg_base + CK_INTC_ICR);
245
246 ck_set_gc(node, reg_base, CK_INTC_NEN31_00, 0);
247 ck_set_gc(node, reg_base, CK_INTC_NEN63_32, 32);
248
249 setup_irq_channel(0x00010203, reg_base + CK_INTC_SOURCE);
250
251 set_handle_irq(ck_irq_handler);
252
253 return 0;
254 }
255 IRQCHIP_DECLARE(ck_intc, "csky,apb-intc", ck_intc_init);
256
257 static int __init
ck_dual_intc_init(struct device_node * node,struct device_node * parent)258 ck_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(0, reg_base + CK_INTC_NEN31_00 + CK_INTC_DUAL_BASE);
271 writel(0, reg_base + CK_INTC_NEN63_32 + CK_INTC_DUAL_BASE);
272
273 ck_set_gc(node, reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN31_00, 64);
274 ck_set_gc(node, reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN63_32, 96);
275
276 setup_irq_channel(0x00010203,
277 reg_base + CK_INTC_SOURCE + CK_INTC_DUAL_BASE);
278
279 return 0;
280 }
281 IRQCHIP_DECLARE(ck_dual_intc, "csky,dual-apb-intc", ck_dual_intc_init);
282