1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for the Microchip LAN966x outbound interrupt controller
4 *
5 * Copyright (c) 2024 Technology Inc. and its subsidiaries.
6 *
7 * Authors:
8 * Horatiu Vultur <horatiu.vultur@microchip.com>
9 * Clément Léger <clement.leger@bootlin.com>
10 * Herve Codina <herve.codina@bootlin.com>
11 */
12
13 #include <linux/interrupt.h>
14 #include <linux/irqchip/chained_irq.h>
15 #include <linux/irqchip.h>
16 #include <linux/irq.h>
17 #include <linux/mod_devicetable.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21
22 struct lan966x_oic_chip_regs {
23 int reg_off_ena_set;
24 int reg_off_ena_clr;
25 int reg_off_sticky;
26 int reg_off_ident;
27 int reg_off_map;
28 };
29
30 struct lan966x_oic_data {
31 void __iomem *regs;
32 int irq;
33 };
34
35 #define LAN966X_OIC_NR_IRQ 86
36
37 /* Interrupt sticky status */
38 #define LAN966X_OIC_INTR_STICKY 0x30
39 #define LAN966X_OIC_INTR_STICKY1 0x34
40 #define LAN966X_OIC_INTR_STICKY2 0x38
41
42 /* Interrupt enable */
43 #define LAN966X_OIC_INTR_ENA 0x48
44 #define LAN966X_OIC_INTR_ENA1 0x4c
45 #define LAN966X_OIC_INTR_ENA2 0x50
46
47 /* Atomic clear of interrupt enable */
48 #define LAN966X_OIC_INTR_ENA_CLR 0x54
49 #define LAN966X_OIC_INTR_ENA_CLR1 0x58
50 #define LAN966X_OIC_INTR_ENA_CLR2 0x5c
51
52 /* Atomic set of interrupt */
53 #define LAN966X_OIC_INTR_ENA_SET 0x60
54 #define LAN966X_OIC_INTR_ENA_SET1 0x64
55 #define LAN966X_OIC_INTR_ENA_SET2 0x68
56
57 /* Mapping of source to destination interrupts (_n = 0..8) */
58 #define LAN966X_OIC_DST_INTR_MAP(_n) (0x78 + (_n) * 4)
59 #define LAN966X_OIC_DST_INTR_MAP1(_n) (0x9c + (_n) * 4)
60 #define LAN966X_OIC_DST_INTR_MAP2(_n) (0xc0 + (_n) * 4)
61
62 /* Currently active interrupt sources per destination (_n = 0..8) */
63 #define LAN966X_OIC_DST_INTR_IDENT(_n) (0xe4 + (_n) * 4)
64 #define LAN966X_OIC_DST_INTR_IDENT1(_n) (0x108 + (_n) * 4)
65 #define LAN966X_OIC_DST_INTR_IDENT2(_n) (0x12c + (_n) * 4)
66
lan966x_oic_irq_startup(struct irq_data * data)67 static unsigned int lan966x_oic_irq_startup(struct irq_data *data)
68 {
69 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
70 struct irq_chip_type *ct = irq_data_get_chip_type(data);
71 struct lan966x_oic_chip_regs *chip_regs = gc->private;
72 u32 map;
73
74 scoped_guard (raw_spinlock, &gc->lock) {
75 /* Map the source interrupt to the destination */
76 map = irq_reg_readl(gc, chip_regs->reg_off_map);
77 map |= data->mask;
78 irq_reg_writel(gc, map, chip_regs->reg_off_map);
79 }
80
81 ct->chip.irq_ack(data);
82 ct->chip.irq_unmask(data);
83
84 return 0;
85 }
86
lan966x_oic_irq_shutdown(struct irq_data * data)87 static void lan966x_oic_irq_shutdown(struct irq_data *data)
88 {
89 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
90 struct irq_chip_type *ct = irq_data_get_chip_type(data);
91 struct lan966x_oic_chip_regs *chip_regs = gc->private;
92 u32 map;
93
94 ct->chip.irq_mask(data);
95
96 guard(raw_spinlock)(&gc->lock);
97
98 /* Unmap the interrupt */
99 map = irq_reg_readl(gc, chip_regs->reg_off_map);
100 map &= ~data->mask;
101 irq_reg_writel(gc, map, chip_regs->reg_off_map);
102 }
103
lan966x_oic_irq_set_type(struct irq_data * data,unsigned int flow_type)104 static int lan966x_oic_irq_set_type(struct irq_data *data,
105 unsigned int flow_type)
106 {
107 if (flow_type != IRQ_TYPE_LEVEL_HIGH) {
108 pr_err("lan966x oic doesn't support flow type %d\n", flow_type);
109 return -EINVAL;
110 }
111
112 return 0;
113 }
114
lan966x_oic_irq_handler_domain(struct irq_domain * d,u32 first_irq)115 static void lan966x_oic_irq_handler_domain(struct irq_domain *d, u32 first_irq)
116 {
117 struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, first_irq);
118 struct lan966x_oic_chip_regs *chip_regs = gc->private;
119 unsigned long ident;
120 unsigned int hwirq;
121
122 ident = irq_reg_readl(gc, chip_regs->reg_off_ident);
123 if (!ident)
124 return;
125
126 for_each_set_bit(hwirq, &ident, 32)
127 generic_handle_domain_irq(d, hwirq + first_irq);
128 }
129
lan966x_oic_irq_handler(struct irq_desc * desc)130 static void lan966x_oic_irq_handler(struct irq_desc *desc)
131 {
132 struct irq_domain *d = irq_desc_get_handler_data(desc);
133 struct irq_chip *chip = irq_desc_get_chip(desc);
134
135 chained_irq_enter(chip, desc);
136 lan966x_oic_irq_handler_domain(d, 0);
137 lan966x_oic_irq_handler_domain(d, 32);
138 lan966x_oic_irq_handler_domain(d, 64);
139 chained_irq_exit(chip, desc);
140 }
141
142 static struct lan966x_oic_chip_regs lan966x_oic_chip_regs[3] = {
143 {
144 .reg_off_ena_set = LAN966X_OIC_INTR_ENA_SET,
145 .reg_off_ena_clr = LAN966X_OIC_INTR_ENA_CLR,
146 .reg_off_sticky = LAN966X_OIC_INTR_STICKY,
147 .reg_off_ident = LAN966X_OIC_DST_INTR_IDENT(0),
148 .reg_off_map = LAN966X_OIC_DST_INTR_MAP(0),
149 }, {
150 .reg_off_ena_set = LAN966X_OIC_INTR_ENA_SET1,
151 .reg_off_ena_clr = LAN966X_OIC_INTR_ENA_CLR1,
152 .reg_off_sticky = LAN966X_OIC_INTR_STICKY1,
153 .reg_off_ident = LAN966X_OIC_DST_INTR_IDENT1(0),
154 .reg_off_map = LAN966X_OIC_DST_INTR_MAP1(0),
155 }, {
156 .reg_off_ena_set = LAN966X_OIC_INTR_ENA_SET2,
157 .reg_off_ena_clr = LAN966X_OIC_INTR_ENA_CLR2,
158 .reg_off_sticky = LAN966X_OIC_INTR_STICKY2,
159 .reg_off_ident = LAN966X_OIC_DST_INTR_IDENT2(0),
160 .reg_off_map = LAN966X_OIC_DST_INTR_MAP2(0),
161 }
162 };
163
lan966x_oic_chip_init(struct irq_chip_generic * gc)164 static int lan966x_oic_chip_init(struct irq_chip_generic *gc)
165 {
166 struct lan966x_oic_data *lan966x_oic = gc->domain->host_data;
167 struct lan966x_oic_chip_regs *chip_regs;
168
169 chip_regs = &lan966x_oic_chip_regs[gc->irq_base / 32];
170
171 gc->reg_base = lan966x_oic->regs;
172 gc->chip_types[0].regs.enable = chip_regs->reg_off_ena_set;
173 gc->chip_types[0].regs.disable = chip_regs->reg_off_ena_clr;
174 gc->chip_types[0].regs.ack = chip_regs->reg_off_sticky;
175 gc->chip_types[0].chip.irq_startup = lan966x_oic_irq_startup;
176 gc->chip_types[0].chip.irq_shutdown = lan966x_oic_irq_shutdown;
177 gc->chip_types[0].chip.irq_set_type = lan966x_oic_irq_set_type;
178 gc->chip_types[0].chip.irq_mask = irq_gc_mask_disable_reg;
179 gc->chip_types[0].chip.irq_unmask = irq_gc_unmask_enable_reg;
180 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
181 gc->private = chip_regs;
182
183 /* Disable all interrupts handled by this chip */
184 irq_reg_writel(gc, ~0U, chip_regs->reg_off_ena_clr);
185
186 return 0;
187 }
188
lan966x_oic_chip_exit(struct irq_chip_generic * gc)189 static void lan966x_oic_chip_exit(struct irq_chip_generic *gc)
190 {
191 /* Disable and ack all interrupts handled by this chip */
192 irq_reg_writel(gc, ~0U, gc->chip_types[0].regs.disable);
193 irq_reg_writel(gc, ~0U, gc->chip_types[0].regs.ack);
194 }
195
lan966x_oic_domain_init(struct irq_domain * d)196 static int lan966x_oic_domain_init(struct irq_domain *d)
197 {
198 struct lan966x_oic_data *lan966x_oic = d->host_data;
199
200 irq_set_chained_handler_and_data(lan966x_oic->irq, lan966x_oic_irq_handler, d);
201
202 return 0;
203 }
204
lan966x_oic_domain_exit(struct irq_domain * d)205 static void lan966x_oic_domain_exit(struct irq_domain *d)
206 {
207 struct lan966x_oic_data *lan966x_oic = d->host_data;
208
209 irq_set_chained_handler_and_data(lan966x_oic->irq, NULL, NULL);
210 }
211
lan966x_oic_probe(struct platform_device * pdev)212 static int lan966x_oic_probe(struct platform_device *pdev)
213 {
214 struct irq_domain_chip_generic_info dgc_info = {
215 .name = "lan966x-oic",
216 .handler = handle_level_irq,
217 .irqs_per_chip = 32,
218 .num_ct = 1,
219 .init = lan966x_oic_chip_init,
220 .exit = lan966x_oic_chip_exit,
221 };
222 struct irq_domain_info d_info = {
223 .fwnode = of_fwnode_handle(pdev->dev.of_node),
224 .domain_flags = IRQ_DOMAIN_FLAG_DESTROY_GC,
225 .size = LAN966X_OIC_NR_IRQ,
226 .hwirq_max = LAN966X_OIC_NR_IRQ,
227 .ops = &irq_generic_chip_ops,
228 .dgc_info = &dgc_info,
229 .init = lan966x_oic_domain_init,
230 .exit = lan966x_oic_domain_exit,
231 };
232 struct lan966x_oic_data *lan966x_oic;
233 struct device *dev = &pdev->dev;
234 struct irq_domain *domain;
235
236 lan966x_oic = devm_kmalloc(dev, sizeof(*lan966x_oic), GFP_KERNEL);
237 if (!lan966x_oic)
238 return -ENOMEM;
239
240 lan966x_oic->regs = devm_platform_ioremap_resource(pdev, 0);
241 if (IS_ERR(lan966x_oic->regs))
242 return dev_err_probe(dev, PTR_ERR(lan966x_oic->regs),
243 "failed to map resource\n");
244
245 lan966x_oic->irq = platform_get_irq(pdev, 0);
246 if (lan966x_oic->irq < 0)
247 return dev_err_probe(dev, lan966x_oic->irq, "failed to get the IRQ\n");
248
249 d_info.host_data = lan966x_oic;
250 domain = devm_irq_domain_instantiate(dev, &d_info);
251 if (IS_ERR(domain))
252 return dev_err_probe(dev, PTR_ERR(domain),
253 "failed to instantiate the IRQ domain\n");
254 return 0;
255 }
256
257 static const struct of_device_id lan966x_oic_of_match[] = {
258 { .compatible = "microchip,lan966x-oic" },
259 {} /* sentinel */
260 };
261 MODULE_DEVICE_TABLE(of, lan966x_oic_of_match);
262
263 static struct platform_driver lan966x_oic_driver = {
264 .probe = lan966x_oic_probe,
265 .driver = {
266 .name = "lan966x-oic",
267 .of_match_table = lan966x_oic_of_match,
268 },
269 };
270 module_platform_driver(lan966x_oic_driver);
271
272 MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
273 MODULE_DESCRIPTION("Microchip LAN966x OIC driver");
274 MODULE_LICENSE("GPL");
275