xref: /openbmc/linux/arch/arm/mach-pxa/irq.c (revision ebd09753) 
1 /*
2  *  linux/arch/arm/mach-pxa/irq.c
3  *
4  *  Generic PXA IRQ handling
5  *
6  *  Author:	Nicolas Pitre
7  *  Created:	Jun 15, 2001
8  *  Copyright:	MontaVista Software Inc.
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License version 2 as
12  *  published by the Free Software Foundation.
13  */
14 #include <linux/bitops.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/syscore_ops.h>
19 #include <linux/io.h>
20 #include <linux/irq.h>
21 #include <linux/of_address.h>
22 #include <linux/of_irq.h>
23 
24 #include <asm/exception.h>
25 
26 #include <mach/hardware.h>
27 #include <mach/irqs.h>
28 
29 #include "generic.h"
30 
31 #define ICIP			(0x000)
32 #define ICMR			(0x004)
33 #define ICLR			(0x008)
34 #define ICFR			(0x00c)
35 #define ICPR			(0x010)
36 #define ICCR			(0x014)
37 #define ICHP			(0x018)
38 #define IPR(i)			(((i) < 32) ? (0x01c + ((i) << 2)) :		\
39 				((i) < 64) ? (0x0b0 + (((i) - 32) << 2)) :	\
40 				      (0x144 + (((i) - 64) << 2)))
41 #define ICHP_VAL_IRQ		(1 << 31)
42 #define ICHP_IRQ(i)		(((i) >> 16) & 0x7fff)
43 #define IPR_VALID		(1 << 31)
44 
45 #define MAX_INTERNAL_IRQS	128
46 
47 /*
48  * This is for peripheral IRQs internal to the PXA chip.
49  */
50 
51 static void __iomem *pxa_irq_base;
52 static int pxa_internal_irq_nr;
53 static bool cpu_has_ipr;
54 static struct irq_domain *pxa_irq_domain;
55 
56 static inline void __iomem *irq_base(int i)
57 {
58 	static unsigned long phys_base_offset[] = {
59 		0x0,
60 		0x9c,
61 		0x130,
62 	};
63 
64 	return pxa_irq_base + phys_base_offset[i];
65 }
66 
67 void pxa_mask_irq(struct irq_data *d)
68 {
69 	void __iomem *base = irq_data_get_irq_chip_data(d);
70 	irq_hw_number_t irq = irqd_to_hwirq(d);
71 	uint32_t icmr = __raw_readl(base + ICMR);
72 
73 	icmr &= ~BIT(irq & 0x1f);
74 	__raw_writel(icmr, base + ICMR);
75 }
76 
77 void pxa_unmask_irq(struct irq_data *d)
78 {
79 	void __iomem *base = irq_data_get_irq_chip_data(d);
80 	irq_hw_number_t irq = irqd_to_hwirq(d);
81 	uint32_t icmr = __raw_readl(base + ICMR);
82 
83 	icmr |= BIT(irq & 0x1f);
84 	__raw_writel(icmr, base + ICMR);
85 }
86 
87 static struct irq_chip pxa_internal_irq_chip = {
88 	.name		= "SC",
89 	.irq_ack	= pxa_mask_irq,
90 	.irq_mask	= pxa_mask_irq,
91 	.irq_unmask	= pxa_unmask_irq,
92 };
93 
94 asmlinkage void __exception_irq_entry icip_handle_irq(struct pt_regs *regs)
95 {
96 	uint32_t icip, icmr, mask;
97 
98 	do {
99 		icip = __raw_readl(pxa_irq_base + ICIP);
100 		icmr = __raw_readl(pxa_irq_base + ICMR);
101 		mask = icip & icmr;
102 
103 		if (mask == 0)
104 			break;
105 
106 		handle_IRQ(PXA_IRQ(fls(mask) - 1), regs);
107 	} while (1);
108 }
109 
110 asmlinkage void __exception_irq_entry ichp_handle_irq(struct pt_regs *regs)
111 {
112 	uint32_t ichp;
113 
114 	do {
115 		__asm__ __volatile__("mrc p6, 0, %0, c5, c0, 0\n": "=r"(ichp));
116 
117 		if ((ichp & ICHP_VAL_IRQ) == 0)
118 			break;
119 
120 		handle_IRQ(PXA_IRQ(ICHP_IRQ(ichp)), regs);
121 	} while (1);
122 }
123 
124 static int pxa_irq_map(struct irq_domain *h, unsigned int virq,
125 		       irq_hw_number_t hw)
126 {
127 	void __iomem *base = irq_base(hw / 32);
128 
129 	/* initialize interrupt priority */
130 	if (cpu_has_ipr)
131 		__raw_writel(hw | IPR_VALID, pxa_irq_base + IPR(hw));
132 
133 	irq_set_chip_and_handler(virq, &pxa_internal_irq_chip,
134 				 handle_level_irq);
135 	irq_set_chip_data(virq, base);
136 
137 	return 0;
138 }
139 
140 static const struct irq_domain_ops pxa_irq_ops = {
141 	.map    = pxa_irq_map,
142 	.xlate  = irq_domain_xlate_onecell,
143 };
144 
145 static __init void
146 pxa_init_irq_common(struct device_node *node, int irq_nr,
147 		    int (*fn)(struct irq_data *, unsigned int))
148 {
149 	int n;
150 
151 	pxa_internal_irq_nr = irq_nr;
152 	pxa_irq_domain = irq_domain_add_legacy(node, irq_nr,
153 					       PXA_IRQ(0), 0,
154 					       &pxa_irq_ops, NULL);
155 	if (!pxa_irq_domain)
156 		panic("Unable to add PXA IRQ domain\n");
157 	irq_set_default_host(pxa_irq_domain);
158 
159 	for (n = 0; n < irq_nr; n += 32) {
160 		void __iomem *base = irq_base(n >> 5);
161 
162 		__raw_writel(0, base + ICMR);	/* disable all IRQs */
163 		__raw_writel(0, base + ICLR);	/* all IRQs are IRQ, not FIQ */
164 	}
165 	/* only unmasked interrupts kick us out of idle */
166 	__raw_writel(1, irq_base(0) + ICCR);
167 
168 	pxa_internal_irq_chip.irq_set_wake = fn;
169 }
170 
171 void __init pxa_init_irq(int irq_nr, int (*fn)(struct irq_data *, unsigned int))
172 {
173 	BUG_ON(irq_nr > MAX_INTERNAL_IRQS);
174 
175 	pxa_irq_base = io_p2v(0x40d00000);
176 	cpu_has_ipr = !cpu_is_pxa25x();
177 	pxa_init_irq_common(NULL, irq_nr, fn);
178 }
179 
180 #ifdef CONFIG_PM
181 static unsigned long saved_icmr[MAX_INTERNAL_IRQS/32];
182 static unsigned long saved_ipr[MAX_INTERNAL_IRQS];
183 
184 static int pxa_irq_suspend(void)
185 {
186 	int i;
187 
188 	for (i = 0; i < DIV_ROUND_UP(pxa_internal_irq_nr, 32); i++) {
189 		void __iomem *base = irq_base(i);
190 
191 		saved_icmr[i] = __raw_readl(base + ICMR);
192 		__raw_writel(0, base + ICMR);
193 	}
194 
195 	if (cpu_has_ipr) {
196 		for (i = 0; i < pxa_internal_irq_nr; i++)
197 			saved_ipr[i] = __raw_readl(pxa_irq_base + IPR(i));
198 	}
199 
200 	return 0;
201 }
202 
203 static void pxa_irq_resume(void)
204 {
205 	int i;
206 
207 	for (i = 0; i < DIV_ROUND_UP(pxa_internal_irq_nr, 32); i++) {
208 		void __iomem *base = irq_base(i);
209 
210 		__raw_writel(saved_icmr[i], base + ICMR);
211 		__raw_writel(0, base + ICLR);
212 	}
213 
214 	if (cpu_has_ipr)
215 		for (i = 0; i < pxa_internal_irq_nr; i++)
216 			__raw_writel(saved_ipr[i], pxa_irq_base + IPR(i));
217 
218 	__raw_writel(1, pxa_irq_base + ICCR);
219 }
220 #else
221 #define pxa_irq_suspend		NULL
222 #define pxa_irq_resume		NULL
223 #endif
224 
225 struct syscore_ops pxa_irq_syscore_ops = {
226 	.suspend	= pxa_irq_suspend,
227 	.resume		= pxa_irq_resume,
228 };
229 
230 #ifdef CONFIG_OF
231 static const struct of_device_id intc_ids[] __initconst = {
232 	{ .compatible = "marvell,pxa-intc", },
233 	{}
234 };
235 
236 void __init pxa_dt_irq_init(int (*fn)(struct irq_data *, unsigned int))
237 {
238 	struct device_node *node;
239 	struct resource res;
240 	int ret;
241 
242 	node = of_find_matching_node(NULL, intc_ids);
243 	if (!node) {
244 		pr_err("Failed to find interrupt controller in arch-pxa\n");
245 		return;
246 	}
247 
248 	ret = of_property_read_u32(node, "marvell,intc-nr-irqs",
249 				   &pxa_internal_irq_nr);
250 	if (ret) {
251 		pr_err("Not found marvell,intc-nr-irqs property\n");
252 		return;
253 	}
254 
255 	ret = of_address_to_resource(node, 0, &res);
256 	if (ret < 0) {
257 		pr_err("No registers defined for node\n");
258 		return;
259 	}
260 	pxa_irq_base = io_p2v(res.start);
261 
262 	if (of_find_property(node, "marvell,intc-priority", NULL))
263 		cpu_has_ipr = 1;
264 
265 	ret = irq_alloc_descs(-1, 0, pxa_internal_irq_nr, 0);
266 	if (ret < 0) {
267 		pr_err("Failed to allocate IRQ numbers\n");
268 		return;
269 	}
270 
271 	pxa_init_irq_common(node, pxa_internal_irq_nr, fn);
272 }
273 #endif /* CONFIG_OF */
274