xref: /openbmc/linux/drivers/irqchip/irq-mxs.c (revision 5b7e5676)
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/irqchip/mxs.h>
13 #include <linux/irqdomain.h>
14 #include <linux/io.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/stmp_device.h>
19 #include <asm/exception.h>
20 
21 #include "alphascale_asm9260-icoll.h"
22 
23 /*
24  * this device provide 4 offsets for each register:
25  * 0x0 - plain read write mode
26  * 0x4 - set mode, OR logic.
27  * 0x8 - clr mode, XOR logic.
28  * 0xc - togle mode.
29  */
30 #define SET_REG 4
31 #define CLR_REG 8
32 
33 #define HW_ICOLL_VECTOR				0x0000
34 #define HW_ICOLL_LEVELACK			0x0010
35 #define HW_ICOLL_CTRL				0x0020
36 #define HW_ICOLL_STAT_OFFSET			0x0070
37 #define HW_ICOLL_INTERRUPT0			0x0120
38 #define HW_ICOLL_INTERRUPTn(n)			((n) * 0x10)
39 #define BM_ICOLL_INTR_ENABLE			BIT(2)
40 #define BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0	0x1
41 
42 #define ICOLL_NUM_IRQS		128
43 
44 enum icoll_type {
45 	ICOLL,
46 	ASM9260_ICOLL,
47 };
48 
49 struct icoll_priv {
50 	void __iomem *vector;
51 	void __iomem *levelack;
52 	void __iomem *ctrl;
53 	void __iomem *stat;
54 	void __iomem *intr;
55 	void __iomem *clear;
56 	enum icoll_type type;
57 };
58 
59 static struct icoll_priv icoll_priv;
60 static struct irq_domain *icoll_domain;
61 
62 /* calculate bit offset depending on number of interrupt per register */
63 static u32 icoll_intr_bitshift(struct irq_data *d, u32 bit)
64 {
65 	/*
66 	 * mask lower part of hwirq to convert it
67 	 * in 0, 1, 2 or 3 and then multiply it by 8 (or shift by 3)
68 	 */
69 	return bit << ((d->hwirq & 3) << 3);
70 }
71 
72 /* calculate mem offset depending on number of interrupt per register */
73 static void __iomem *icoll_intr_reg(struct irq_data *d)
74 {
75 	/* offset = hwirq / intr_per_reg * 0x10 */
76 	return icoll_priv.intr + ((d->hwirq >> 2) * 0x10);
77 }
78 
79 static void icoll_ack_irq(struct irq_data *d)
80 {
81 	/*
82 	 * The Interrupt Collector is able to prioritize irqs.
83 	 * Currently only level 0 is used. So acking can use
84 	 * BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 unconditionally.
85 	 */
86 	__raw_writel(BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0,
87 			icoll_priv.levelack);
88 }
89 
90 static void icoll_mask_irq(struct irq_data *d)
91 {
92 	__raw_writel(BM_ICOLL_INTR_ENABLE,
93 			icoll_priv.intr + CLR_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
94 }
95 
96 static void icoll_unmask_irq(struct irq_data *d)
97 {
98 	__raw_writel(BM_ICOLL_INTR_ENABLE,
99 			icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
100 }
101 
102 static void asm9260_mask_irq(struct irq_data *d)
103 {
104 	__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
105 			icoll_intr_reg(d) + CLR_REG);
106 }
107 
108 static void asm9260_unmask_irq(struct irq_data *d)
109 {
110 	__raw_writel(ASM9260_BM_CLEAR_BIT(d->hwirq),
111 		     icoll_priv.clear +
112 		     ASM9260_HW_ICOLL_CLEARn(d->hwirq));
113 
114 	__raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
115 			icoll_intr_reg(d) + SET_REG);
116 }
117 
118 static struct irq_chip mxs_icoll_chip = {
119 	.irq_ack = icoll_ack_irq,
120 	.irq_mask = icoll_mask_irq,
121 	.irq_unmask = icoll_unmask_irq,
122 	.flags = IRQCHIP_MASK_ON_SUSPEND |
123 		 IRQCHIP_SKIP_SET_WAKE,
124 };
125 
126 static struct irq_chip asm9260_icoll_chip = {
127 	.irq_ack = icoll_ack_irq,
128 	.irq_mask = asm9260_mask_irq,
129 	.irq_unmask = asm9260_unmask_irq,
130 	.flags = IRQCHIP_MASK_ON_SUSPEND |
131 		 IRQCHIP_SKIP_SET_WAKE,
132 };
133 
134 asmlinkage void __exception_irq_entry icoll_handle_irq(struct pt_regs *regs)
135 {
136 	u32 irqnr;
137 
138 	irqnr = __raw_readl(icoll_priv.stat);
139 	__raw_writel(irqnr, icoll_priv.vector);
140 	generic_handle_domain_irq(icoll_domain, irqnr);
141 }
142 
143 static int icoll_irq_domain_map(struct irq_domain *d, unsigned int virq,
144 				irq_hw_number_t hw)
145 {
146 	struct irq_chip *chip;
147 
148 	if (icoll_priv.type == ICOLL)
149 		chip = &mxs_icoll_chip;
150 	else
151 		chip = &asm9260_icoll_chip;
152 
153 	irq_set_chip_and_handler(virq, chip, handle_level_irq);
154 
155 	return 0;
156 }
157 
158 static const struct irq_domain_ops icoll_irq_domain_ops = {
159 	.map = icoll_irq_domain_map,
160 	.xlate = irq_domain_xlate_onecell,
161 };
162 
163 static void __init icoll_add_domain(struct device_node *np,
164 			  int num)
165 {
166 	icoll_domain = irq_domain_add_linear(np, num,
167 					     &icoll_irq_domain_ops, NULL);
168 
169 	if (!icoll_domain)
170 		panic("%pOF: unable to create irq domain", np);
171 }
172 
173 static void __iomem * __init icoll_init_iobase(struct device_node *np)
174 {
175 	void __iomem *icoll_base;
176 
177 	icoll_base = of_io_request_and_map(np, 0, np->name);
178 	if (IS_ERR(icoll_base))
179 		panic("%pOF: unable to map resource", np);
180 	return icoll_base;
181 }
182 
183 static int __init icoll_of_init(struct device_node *np,
184 			  struct device_node *interrupt_parent)
185 {
186 	void __iomem *icoll_base;
187 
188 	icoll_priv.type = ICOLL;
189 
190 	icoll_base		= icoll_init_iobase(np);
191 	icoll_priv.vector	= icoll_base + HW_ICOLL_VECTOR;
192 	icoll_priv.levelack	= icoll_base + HW_ICOLL_LEVELACK;
193 	icoll_priv.ctrl		= icoll_base + HW_ICOLL_CTRL;
194 	icoll_priv.stat		= icoll_base + HW_ICOLL_STAT_OFFSET;
195 	icoll_priv.intr		= icoll_base + HW_ICOLL_INTERRUPT0;
196 	icoll_priv.clear	= NULL;
197 
198 	/*
199 	 * Interrupt Collector reset, which initializes the priority
200 	 * for each irq to level 0.
201 	 */
202 	stmp_reset_block(icoll_priv.ctrl);
203 
204 	icoll_add_domain(np, ICOLL_NUM_IRQS);
205 
206 	return 0;
207 }
208 IRQCHIP_DECLARE(mxs, "fsl,icoll", icoll_of_init);
209 
210 static int __init asm9260_of_init(struct device_node *np,
211 			  struct device_node *interrupt_parent)
212 {
213 	void __iomem *icoll_base;
214 	int i;
215 
216 	icoll_priv.type = ASM9260_ICOLL;
217 
218 	icoll_base = icoll_init_iobase(np);
219 	icoll_priv.vector	= icoll_base + ASM9260_HW_ICOLL_VECTOR;
220 	icoll_priv.levelack	= icoll_base + ASM9260_HW_ICOLL_LEVELACK;
221 	icoll_priv.ctrl		= icoll_base + ASM9260_HW_ICOLL_CTRL;
222 	icoll_priv.stat		= icoll_base + ASM9260_HW_ICOLL_STAT_OFFSET;
223 	icoll_priv.intr		= icoll_base + ASM9260_HW_ICOLL_INTERRUPT0;
224 	icoll_priv.clear	= icoll_base + ASM9260_HW_ICOLL_CLEAR0;
225 
226 	writel_relaxed(ASM9260_BM_CTRL_IRQ_ENABLE,
227 			icoll_priv.ctrl);
228 	/*
229 	 * ASM9260 don't provide reset bit. So, we need to set level 0
230 	 * manually.
231 	 */
232 	for (i = 0; i < 16 * 0x10; i += 0x10)
233 		writel(0, icoll_priv.intr + i);
234 
235 	icoll_add_domain(np, ASM9260_NUM_IRQS);
236 	set_handle_irq(icoll_handle_irq);
237 
238 	return 0;
239 }
240 IRQCHIP_DECLARE(asm9260, "alphascale,asm9260-icoll", asm9260_of_init);
241