xref: /openbmc/linux/drivers/irqchip/irq-mxs.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
4  * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
5  *	Add Alphascale ASM9260 support.
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/irq.h>
11 #include <linux/irqchip.h>
12 #include <linux/irqdomain.h>
13 #include <linux/io.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17 #include <linux/stmp_device.h>
18 #include <asm/exception.h>
19 
20 #include "alphascale_asm9260-icoll.h"
21 
22 /*
23  * this device provide 4 offsets for each register:
24  * 0x0 - plain read write mode
25  * 0x4 - set mode, OR logic.
26  * 0x8 - clr mode, XOR logic.
27  * 0xc - togle mode.
28  */
29 #define SET_REG 4
30 #define CLR_REG 8
31 
32 #define HW_ICOLL_VECTOR				0x0000
33 #define HW_ICOLL_LEVELACK			0x0010
34 #define HW_ICOLL_CTRL				0x0020
35 #define HW_ICOLL_STAT_OFFSET			0x0070
36 #define HW_ICOLL_INTERRUPT0			0x0120
37 #define HW_ICOLL_INTERRUPTn(n)			((n) * 0x10)
38 #define BM_ICOLL_INTR_ENABLE			BIT(2)
39 #define BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0	0x1
40 
41 #define ICOLL_NUM_IRQS		128
42 
43 enum icoll_type {
44 	ICOLL,
45 	ASM9260_ICOLL,
46 };
47 
48 struct icoll_priv {
49 	void __iomem *vector;
50 	void __iomem *levelack;
51 	void __iomem *ctrl;
52 	void __iomem *stat;
53 	void __iomem *intr;
54 	void __iomem *clear;
55 	enum icoll_type type;
56 };
57 
58 static struct icoll_priv icoll_priv;
59 static struct irq_domain *icoll_domain;
60 
61 /* calculate bit offset depending on number of intterupt per register */
62 static u32 icoll_intr_bitshift(struct irq_data *d, u32 bit)
63 {
64 	/*
65 	 * mask lower part of hwirq to convert it
66 	 * in 0, 1, 2 or 3 and then multiply it by 8 (or shift by 3)
67 	 */
68 	return bit << ((d->hwirq & 3) << 3);
69 }
70 
71 /* calculate mem offset depending on number of intterupt per register */
72 static void __iomem *icoll_intr_reg(struct irq_data *d)
73 {
74 	/* offset = hwirq / intr_per_reg * 0x10 */
75 	return icoll_priv.intr + ((d->hwirq >> 2) * 0x10);
76 }
77 
78 static void icoll_ack_irq(struct irq_data *d)
79 {
80 	/*
81 	 * The Interrupt Collector is able to prioritize irqs.
82 	 * Currently only level 0 is used. So acking can use
83 	 * BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 unconditionally.
84 	 */
85 	__raw_writel(BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0,
86 			icoll_priv.levelack);
87 }
88 
89 static void icoll_mask_irq(struct irq_data *d)
90 {
91 	__raw_writel(BM_ICOLL_INTR_ENABLE,
92 			icoll_priv.intr + CLR_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
93 }
94 
95 static void icoll_unmask_irq(struct irq_data *d)
96 {
97 	__raw_writel(BM_ICOLL_INTR_ENABLE,
98 			icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
99 }
100 
101 static void asm9260_mask_irq(struct irq_data *d)
102 {
103 	__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
104 			icoll_intr_reg(d) + CLR_REG);
105 }
106 
107 static void asm9260_unmask_irq(struct irq_data *d)
108 {
109 	__raw_writel(ASM9260_BM_CLEAR_BIT(d->hwirq),
110 		     icoll_priv.clear +
111 		     ASM9260_HW_ICOLL_CLEARn(d->hwirq));
112 
113 	__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
114 			icoll_intr_reg(d) + SET_REG);
115 }
116 
117 static struct irq_chip mxs_icoll_chip = {
118 	.irq_ack = icoll_ack_irq,
119 	.irq_mask = icoll_mask_irq,
120 	.irq_unmask = icoll_unmask_irq,
121 	.flags = IRQCHIP_MASK_ON_SUSPEND |
122 		 IRQCHIP_SKIP_SET_WAKE,
123 };
124 
125 static struct irq_chip asm9260_icoll_chip = {
126 	.irq_ack = icoll_ack_irq,
127 	.irq_mask = asm9260_mask_irq,
128 	.irq_unmask = asm9260_unmask_irq,
129 	.flags = IRQCHIP_MASK_ON_SUSPEND |
130 		 IRQCHIP_SKIP_SET_WAKE,
131 };
132 
133 asmlinkage void __exception_irq_entry icoll_handle_irq(struct pt_regs *regs)
134 {
135 	u32 irqnr;
136 
137 	irqnr = __raw_readl(icoll_priv.stat);
138 	__raw_writel(irqnr, icoll_priv.vector);
139 	handle_domain_irq(icoll_domain, irqnr, regs);
140 }
141 
142 static int icoll_irq_domain_map(struct irq_domain *d, unsigned int virq,
143 				irq_hw_number_t hw)
144 {
145 	struct irq_chip *chip;
146 
147 	if (icoll_priv.type == ICOLL)
148 		chip = &mxs_icoll_chip;
149 	else
150 		chip = &asm9260_icoll_chip;
151 
152 	irq_set_chip_and_handler(virq, chip, handle_level_irq);
153 
154 	return 0;
155 }
156 
157 static const struct irq_domain_ops icoll_irq_domain_ops = {
158 	.map = icoll_irq_domain_map,
159 	.xlate = irq_domain_xlate_onecell,
160 };
161 
162 static void __init icoll_add_domain(struct device_node *np,
163 			  int num)
164 {
165 	icoll_domain = irq_domain_add_linear(np, num,
166 					     &icoll_irq_domain_ops, NULL);
167 
168 	if (!icoll_domain)
169 		panic("%pOF: unable to create irq domain", np);
170 }
171 
172 static void __iomem * __init icoll_init_iobase(struct device_node *np)
173 {
174 	void __iomem *icoll_base;
175 
176 	icoll_base = of_io_request_and_map(np, 0, np->name);
177 	if (IS_ERR(icoll_base))
178 		panic("%pOF: unable to map resource", np);
179 	return icoll_base;
180 }
181 
182 static int __init icoll_of_init(struct device_node *np,
183 			  struct device_node *interrupt_parent)
184 {
185 	void __iomem *icoll_base;
186 
187 	icoll_priv.type = ICOLL;
188 
189 	icoll_base		= icoll_init_iobase(np);
190 	icoll_priv.vector	= icoll_base + HW_ICOLL_VECTOR;
191 	icoll_priv.levelack	= icoll_base + HW_ICOLL_LEVELACK;
192 	icoll_priv.ctrl		= icoll_base + HW_ICOLL_CTRL;
193 	icoll_priv.stat		= icoll_base + HW_ICOLL_STAT_OFFSET;
194 	icoll_priv.intr		= icoll_base + HW_ICOLL_INTERRUPT0;
195 	icoll_priv.clear	= NULL;
196 
197 	/*
198 	 * Interrupt Collector reset, which initializes the priority
199 	 * for each irq to level 0.
200 	 */
201 	stmp_reset_block(icoll_priv.ctrl);
202 
203 	icoll_add_domain(np, ICOLL_NUM_IRQS);
204 
205 	return 0;
206 }
207 IRQCHIP_DECLARE(mxs, "fsl,icoll", icoll_of_init);
208 
209 static int __init asm9260_of_init(struct device_node *np,
210 			  struct device_node *interrupt_parent)
211 {
212 	void __iomem *icoll_base;
213 	int i;
214 
215 	icoll_priv.type = ASM9260_ICOLL;
216 
217 	icoll_base = icoll_init_iobase(np);
218 	icoll_priv.vector	= icoll_base + ASM9260_HW_ICOLL_VECTOR;
219 	icoll_priv.levelack	= icoll_base + ASM9260_HW_ICOLL_LEVELACK;
220 	icoll_priv.ctrl		= icoll_base + ASM9260_HW_ICOLL_CTRL;
221 	icoll_priv.stat		= icoll_base + ASM9260_HW_ICOLL_STAT_OFFSET;
222 	icoll_priv.intr		= icoll_base + ASM9260_HW_ICOLL_INTERRUPT0;
223 	icoll_priv.clear	= icoll_base + ASM9260_HW_ICOLL_CLEAR0;
224 
225 	writel_relaxed(ASM9260_BM_CTRL_IRQ_ENABLE,
226 			icoll_priv.ctrl);
227 	/*
228 	 * ASM9260 don't provide reset bit. So, we need to set level 0
229 	 * manually.
230 	 */
231 	for (i = 0; i < 16 * 0x10; i += 0x10)
232 		writel(0, icoll_priv.intr + i);
233 
234 	icoll_add_domain(np, ASM9260_NUM_IRQS);
235 	set_handle_irq(icoll_handle_irq);
236 
237 	return 0;
238 }
239 IRQCHIP_DECLARE(asm9260, "alphascale,asm9260-icoll", asm9260_of_init);
240