1/*
2 * Interrupt handling for Marvell mv64360/mv64460 host bridges (Discovery)
3 *
4 * Author: Dale Farnsworth <dale@farnsworth.org>
5 *
6 * 2007 (c) MontaVista, Software, Inc.  This file is licensed under
7 * the terms of the GNU General Public License version 2.  This program
8 * is licensed "as is" without any warranty of any kind, whether express
9 * or implied.
10 */
11
12#include <linux/stddef.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/irq.h>
16#include <linux/interrupt.h>
17#include <linux/spinlock.h>
18
19#include <asm/byteorder.h>
20#include <asm/io.h>
21#include <asm/prom.h>
22#include <asm/irq.h>
23
24#include "mv64x60.h"
25
26/* Interrupt Controller Interface Registers */
27#define MV64X60_IC_MAIN_CAUSE_LO	0x0004
28#define MV64X60_IC_MAIN_CAUSE_HI	0x000c
29#define MV64X60_IC_CPU0_INTR_MASK_LO	0x0014
30#define MV64X60_IC_CPU0_INTR_MASK_HI	0x001c
31#define MV64X60_IC_CPU0_SELECT_CAUSE	0x0024
32
33#define MV64X60_HIGH_GPP_GROUPS		0x0f000000
34#define MV64X60_SELECT_CAUSE_HIGH	0x40000000
35
36/* General Purpose Pins Controller Interface Registers */
37#define MV64x60_GPP_INTR_CAUSE		0x0008
38#define MV64x60_GPP_INTR_MASK		0x000c
39
40#define MV64x60_LEVEL1_LOW		0
41#define MV64x60_LEVEL1_HIGH		1
42#define MV64x60_LEVEL1_GPP		2
43
44#define MV64x60_LEVEL1_MASK		0x00000060
45#define MV64x60_LEVEL1_OFFSET		5
46
47#define MV64x60_LEVEL2_MASK		0x0000001f
48
49#define MV64x60_NUM_IRQS		96
50
51static DEFINE_SPINLOCK(mv64x60_lock);
52
53static void __iomem *mv64x60_irq_reg_base;
54static void __iomem *mv64x60_gpp_reg_base;
55
56/*
57 * Interrupt Controller Handling
58 *
59 * The interrupt controller handles three groups of interrupts:
60 *   main low:	IRQ0-IRQ31
61 *   main high:	IRQ32-IRQ63
62 *   gpp:	IRQ64-IRQ95
63 *
64 * This code handles interrupts in two levels.  Level 1 selects the
65 * interrupt group, and level 2 selects an IRQ within that group.
66 * Each group has its own irq_chip structure.
67 */
68
69static u32 mv64x60_cached_low_mask;
70static u32 mv64x60_cached_high_mask = MV64X60_HIGH_GPP_GROUPS;
71static u32 mv64x60_cached_gpp_mask;
72
73static struct irq_domain *mv64x60_irq_host;
74
75/*
76 * mv64x60_chip_low functions
77 */
78
79static void mv64x60_mask_low(struct irq_data *d)
80{
81	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
82	unsigned long flags;
83
84	spin_lock_irqsave(&mv64x60_lock, flags);
85	mv64x60_cached_low_mask &= ~(1 << level2);
86	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
87		 mv64x60_cached_low_mask);
88	spin_unlock_irqrestore(&mv64x60_lock, flags);
89	(void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO);
90}
91
92static void mv64x60_unmask_low(struct irq_data *d)
93{
94	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
95	unsigned long flags;
96
97	spin_lock_irqsave(&mv64x60_lock, flags);
98	mv64x60_cached_low_mask |= 1 << level2;
99	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
100		 mv64x60_cached_low_mask);
101	spin_unlock_irqrestore(&mv64x60_lock, flags);
102	(void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO);
103}
104
105static struct irq_chip mv64x60_chip_low = {
106	.name		= "mv64x60_low",
107	.irq_mask	= mv64x60_mask_low,
108	.irq_mask_ack	= mv64x60_mask_low,
109	.irq_unmask	= mv64x60_unmask_low,
110};
111
112/*
113 * mv64x60_chip_high functions
114 */
115
116static void mv64x60_mask_high(struct irq_data *d)
117{
118	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
119	unsigned long flags;
120
121	spin_lock_irqsave(&mv64x60_lock, flags);
122	mv64x60_cached_high_mask &= ~(1 << level2);
123	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
124		 mv64x60_cached_high_mask);
125	spin_unlock_irqrestore(&mv64x60_lock, flags);
126	(void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI);
127}
128
129static void mv64x60_unmask_high(struct irq_data *d)
130{
131	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
132	unsigned long flags;
133
134	spin_lock_irqsave(&mv64x60_lock, flags);
135	mv64x60_cached_high_mask |= 1 << level2;
136	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
137		 mv64x60_cached_high_mask);
138	spin_unlock_irqrestore(&mv64x60_lock, flags);
139	(void)in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI);
140}
141
142static struct irq_chip mv64x60_chip_high = {
143	.name		= "mv64x60_high",
144	.irq_mask	= mv64x60_mask_high,
145	.irq_mask_ack	= mv64x60_mask_high,
146	.irq_unmask	= mv64x60_unmask_high,
147};
148
149/*
150 * mv64x60_chip_gpp functions
151 */
152
153static void mv64x60_mask_gpp(struct irq_data *d)
154{
155	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
156	unsigned long flags;
157
158	spin_lock_irqsave(&mv64x60_lock, flags);
159	mv64x60_cached_gpp_mask &= ~(1 << level2);
160	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
161		 mv64x60_cached_gpp_mask);
162	spin_unlock_irqrestore(&mv64x60_lock, flags);
163	(void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK);
164}
165
166static void mv64x60_mask_ack_gpp(struct irq_data *d)
167{
168	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
169	unsigned long flags;
170
171	spin_lock_irqsave(&mv64x60_lock, flags);
172	mv64x60_cached_gpp_mask &= ~(1 << level2);
173	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
174		 mv64x60_cached_gpp_mask);
175	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE,
176		 ~(1 << level2));
177	spin_unlock_irqrestore(&mv64x60_lock, flags);
178	(void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE);
179}
180
181static void mv64x60_unmask_gpp(struct irq_data *d)
182{
183	int level2 = irqd_to_hwirq(d) & MV64x60_LEVEL2_MASK;
184	unsigned long flags;
185
186	spin_lock_irqsave(&mv64x60_lock, flags);
187	mv64x60_cached_gpp_mask |= 1 << level2;
188	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
189		 mv64x60_cached_gpp_mask);
190	spin_unlock_irqrestore(&mv64x60_lock, flags);
191	(void)in_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK);
192}
193
194static struct irq_chip mv64x60_chip_gpp = {
195	.name		= "mv64x60_gpp",
196	.irq_mask	= mv64x60_mask_gpp,
197	.irq_mask_ack	= mv64x60_mask_ack_gpp,
198	.irq_unmask	= mv64x60_unmask_gpp,
199};
200
201/*
202 * mv64x60_host_ops functions
203 */
204
205static struct irq_chip *mv64x60_chips[] = {
206	[MV64x60_LEVEL1_LOW]  = &mv64x60_chip_low,
207	[MV64x60_LEVEL1_HIGH] = &mv64x60_chip_high,
208	[MV64x60_LEVEL1_GPP]  = &mv64x60_chip_gpp,
209};
210
211static int mv64x60_host_map(struct irq_domain *h, unsigned int virq,
212			  irq_hw_number_t hwirq)
213{
214	int level1;
215
216	irq_set_status_flags(virq, IRQ_LEVEL);
217
218	level1 = (hwirq & MV64x60_LEVEL1_MASK) >> MV64x60_LEVEL1_OFFSET;
219	BUG_ON(level1 > MV64x60_LEVEL1_GPP);
220	irq_set_chip_and_handler(virq, mv64x60_chips[level1],
221				 handle_level_irq);
222
223	return 0;
224}
225
226static struct irq_domain_ops mv64x60_host_ops = {
227	.map   = mv64x60_host_map,
228};
229
230/*
231 * Global functions
232 */
233
234void __init mv64x60_init_irq(void)
235{
236	struct device_node *np;
237	phys_addr_t paddr;
238	unsigned int size;
239	const unsigned int *reg;
240	unsigned long flags;
241
242	np = of_find_compatible_node(NULL, NULL, "marvell,mv64360-gpp");
243	reg = of_get_property(np, "reg", &size);
244	paddr = of_translate_address(np, reg);
245	mv64x60_gpp_reg_base = ioremap(paddr, reg[1]);
246	of_node_put(np);
247
248	np = of_find_compatible_node(NULL, NULL, "marvell,mv64360-pic");
249	reg = of_get_property(np, "reg", &size);
250	paddr = of_translate_address(np, reg);
251	mv64x60_irq_reg_base = ioremap(paddr, reg[1]);
252
253	mv64x60_irq_host = irq_domain_add_linear(np, MV64x60_NUM_IRQS,
254					  &mv64x60_host_ops, NULL);
255
256	spin_lock_irqsave(&mv64x60_lock, flags);
257	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_MASK,
258		 mv64x60_cached_gpp_mask);
259	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_LO,
260		 mv64x60_cached_low_mask);
261	out_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_INTR_MASK_HI,
262		 mv64x60_cached_high_mask);
263
264	out_le32(mv64x60_gpp_reg_base + MV64x60_GPP_INTR_CAUSE, 0);
265	out_le32(mv64x60_irq_reg_base + MV64X60_IC_MAIN_CAUSE_LO, 0);
266	out_le32(mv64x60_irq_reg_base + MV64X60_IC_MAIN_CAUSE_HI, 0);
267	spin_unlock_irqrestore(&mv64x60_lock, flags);
268}
269
270unsigned int mv64x60_get_irq(void)
271{
272	u32 cause;
273	int level1;
274	irq_hw_number_t hwirq;
275	int virq = NO_IRQ;
276
277	cause = in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_SELECT_CAUSE);
278	if (cause & MV64X60_SELECT_CAUSE_HIGH) {
279		cause &= mv64x60_cached_high_mask;
280		level1 = MV64x60_LEVEL1_HIGH;
281		if (cause & MV64X60_HIGH_GPP_GROUPS) {
282			cause = in_le32(mv64x60_gpp_reg_base +
283					MV64x60_GPP_INTR_CAUSE);
284			cause &= mv64x60_cached_gpp_mask;
285			level1 = MV64x60_LEVEL1_GPP;
286		}
287	} else {
288		cause &= mv64x60_cached_low_mask;
289		level1 = MV64x60_LEVEL1_LOW;
290	}
291	if (cause) {
292		hwirq = (level1 << MV64x60_LEVEL1_OFFSET) | __ilog2(cause);
293		virq = irq_linear_revmap(mv64x60_irq_host, hwirq);
294	}
295
296	return virq;
297}
298