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
43enum icoll_type {
44	ICOLL,
45	ASM9260_ICOLL,
46};
47
48struct 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
58static struct icoll_priv icoll_priv;
59static struct irq_domain *icoll_domain;
60
61/* calculate bit offset depending on number of interrupt per register */
62static 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 interrupt per register */
72static 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
78static 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
89static 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
95static 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
101static 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
107static 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
117static 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
125static 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
133asmlinkage 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	generic_handle_domain_irq(icoll_domain, irqnr);
140}
141
142static 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
157static const struct irq_domain_ops icoll_irq_domain_ops = {
158	.map = icoll_irq_domain_map,
159	.xlate = irq_domain_xlate_onecell,
160};
161
162static 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
172static 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
182static 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	set_handle_irq(icoll_handle_irq);
205
206	return 0;
207}
208IRQCHIP_DECLARE(mxs, "fsl,icoll", icoll_of_init);
209
210static 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}
240IRQCHIP_DECLARE(asm9260, "alphascale,asm9260-icoll", asm9260_of_init);
241