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  • only in /netgear-R7000-V1.0.7.12_1.2.5/components/opensource/linux/linux-2.6.36/arch/arm/mach-omap2/
1/*
2 * linux/arch/arm/mach-omap2/irq.c
3 *
4 * Interrupt handler for OMAP2 boards.
5 *
6 * Copyright (C) 2005 Nokia Corporation
7 * Author: Paul Mundt <paul.mundt@nokia.com>
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file "COPYING" in the main directory of this archive
11 * for more details.
12 */
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/interrupt.h>
16#include <linux/io.h>
17#include <mach/hardware.h>
18#include <asm/mach/irq.h>
19
20
21/* selected INTC register offsets */
22
23#define INTC_REVISION		0x0000
24#define INTC_SYSCONFIG		0x0010
25#define INTC_SYSSTATUS		0x0014
26#define INTC_SIR		0x0040
27#define INTC_CONTROL		0x0048
28#define INTC_PROTECTION		0x004C
29#define INTC_IDLE		0x0050
30#define INTC_THRESHOLD		0x0068
31#define INTC_MIR0		0x0084
32#define INTC_MIR_CLEAR0		0x0088
33#define INTC_MIR_SET0		0x008c
34#define INTC_PENDING_IRQ0	0x0098
35/* Number of IRQ state bits in each MIR register */
36#define IRQ_BITS_PER_REG	32
37
38/*
39 * OMAP2 has a number of different interrupt controllers, each interrupt
40 * controller is identified as its own "bank". Register definitions are
41 * fairly consistent for each bank, but not all registers are implemented
42 * for each bank.. when in doubt, consult the TRM.
43 */
44static struct omap_irq_bank {
45	void __iomem *base_reg;
46	unsigned int nr_irqs;
47} __attribute__ ((aligned(4))) irq_banks[] = {
48	{
49		/* MPU INTC */
50		.base_reg	= 0,
51		.nr_irqs	= 96,
52	},
53};
54
55/* Structure to save interrupt controller context */
56struct omap3_intc_regs {
57	u32 sysconfig;
58	u32 protection;
59	u32 idle;
60	u32 threshold;
61	u32 ilr[INTCPS_NR_IRQS];
62	u32 mir[INTCPS_NR_MIR_REGS];
63};
64
65static struct omap3_intc_regs intc_context[ARRAY_SIZE(irq_banks)];
66
67/* INTC bank register get/set */
68
69static void intc_bank_write_reg(u32 val, struct omap_irq_bank *bank, u16 reg)
70{
71	__raw_writel(val, bank->base_reg + reg);
72}
73
74static u32 intc_bank_read_reg(struct omap_irq_bank *bank, u16 reg)
75{
76	return __raw_readl(bank->base_reg + reg);
77}
78
79static int previous_irq;
80
81/*
82 * On 34xx we can get occasional spurious interrupts if the ack from
83 * an interrupt handler does not get posted before we unmask. Warn about
84 * the interrupt handlers that need to flush posted writes.
85 */
86static int omap_check_spurious(unsigned int irq)
87{
88	u32 sir, spurious;
89
90	sir = intc_bank_read_reg(&irq_banks[0], INTC_SIR);
91	spurious = sir >> 7;
92
93	if (spurious) {
94		printk(KERN_WARNING "Spurious irq %i: 0x%08x, please flush "
95					"posted write for irq %i\n",
96					irq, sir, previous_irq);
97		return spurious;
98	}
99
100	return 0;
101}
102
103static void omap_ack_irq(unsigned int irq)
104{
105	intc_bank_write_reg(0x1, &irq_banks[0], INTC_CONTROL);
106}
107
108static void omap_mask_irq(unsigned int irq)
109{
110	int offset = irq & (~(IRQ_BITS_PER_REG - 1));
111
112	if (cpu_is_omap34xx()) {
113		int spurious = 0;
114
115		/*
116		 * INT_34XX_GPT12_IRQ is also the spurious irq. Maybe because
117		 * it is the highest irq number?
118		 */
119		if (irq == INT_34XX_GPT12_IRQ)
120			spurious = omap_check_spurious(irq);
121
122		if (!spurious)
123			previous_irq = irq;
124	}
125
126	irq &= (IRQ_BITS_PER_REG - 1);
127
128	intc_bank_write_reg(1 << irq, &irq_banks[0], INTC_MIR_SET0 + offset);
129}
130
131static void omap_unmask_irq(unsigned int irq)
132{
133	int offset = irq & (~(IRQ_BITS_PER_REG - 1));
134
135	irq &= (IRQ_BITS_PER_REG - 1);
136
137	intc_bank_write_reg(1 << irq, &irq_banks[0], INTC_MIR_CLEAR0 + offset);
138}
139
140static void omap_mask_ack_irq(unsigned int irq)
141{
142	omap_mask_irq(irq);
143	omap_ack_irq(irq);
144}
145
146static struct irq_chip omap_irq_chip = {
147	.name	= "INTC",
148	.ack	= omap_mask_ack_irq,
149	.mask	= omap_mask_irq,
150	.unmask	= omap_unmask_irq,
151};
152
153static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)
154{
155	unsigned long tmp;
156
157	tmp = intc_bank_read_reg(bank, INTC_REVISION) & 0xff;
158	printk(KERN_INFO "IRQ: Found an INTC at 0x%p "
159			 "(revision %ld.%ld) with %d interrupts\n",
160			 bank->base_reg, tmp >> 4, tmp & 0xf, bank->nr_irqs);
161
162	tmp = intc_bank_read_reg(bank, INTC_SYSCONFIG);
163	tmp |= 1 << 1;	/* soft reset */
164	intc_bank_write_reg(tmp, bank, INTC_SYSCONFIG);
165
166	while (!(intc_bank_read_reg(bank, INTC_SYSSTATUS) & 0x1))
167		/* Wait for reset to complete */;
168
169	/* Enable autoidle */
170	intc_bank_write_reg(1 << 0, bank, INTC_SYSCONFIG);
171}
172
173int omap_irq_pending(void)
174{
175	int i;
176
177	for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
178		struct omap_irq_bank *bank = irq_banks + i;
179		int irq;
180
181		for (irq = 0; irq < bank->nr_irqs; irq += 32)
182			if (intc_bank_read_reg(bank, INTC_PENDING_IRQ0 +
183					       ((irq >> 5) << 5)))
184				return 1;
185	}
186	return 0;
187}
188
189void __init omap_init_irq(void)
190{
191	unsigned long nr_of_irqs = 0;
192	unsigned int nr_banks = 0;
193	int i;
194
195	for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
196		unsigned long base = 0;
197		struct omap_irq_bank *bank = irq_banks + i;
198
199		if (cpu_is_omap24xx())
200			base = OMAP24XX_IC_BASE;
201		else if (cpu_is_omap34xx())
202			base = OMAP34XX_IC_BASE;
203
204		BUG_ON(!base);
205
206		/* Static mapping, never released */
207		bank->base_reg = ioremap(base, SZ_4K);
208		if (!bank->base_reg) {
209			printk(KERN_ERR "Could not ioremap irq bank%i\n", i);
210			continue;
211		}
212
213		omap_irq_bank_init_one(bank);
214
215		nr_of_irqs += bank->nr_irqs;
216		nr_banks++;
217	}
218
219	printk(KERN_INFO "Total of %ld interrupts on %d active controller%s\n",
220	       nr_of_irqs, nr_banks, nr_banks > 1 ? "s" : "");
221
222	for (i = 0; i < nr_of_irqs; i++) {
223		set_irq_chip(i, &omap_irq_chip);
224		set_irq_handler(i, handle_level_irq);
225		set_irq_flags(i, IRQF_VALID);
226	}
227}
228
229#ifdef CONFIG_ARCH_OMAP3
230void omap_intc_save_context(void)
231{
232	int ind = 0, i = 0;
233	for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
234		struct omap_irq_bank *bank = irq_banks + ind;
235		intc_context[ind].sysconfig =
236			intc_bank_read_reg(bank, INTC_SYSCONFIG);
237		intc_context[ind].protection =
238			intc_bank_read_reg(bank, INTC_PROTECTION);
239		intc_context[ind].idle =
240			intc_bank_read_reg(bank, INTC_IDLE);
241		intc_context[ind].threshold =
242			intc_bank_read_reg(bank, INTC_THRESHOLD);
243		for (i = 0; i < INTCPS_NR_IRQS; i++)
244			intc_context[ind].ilr[i] =
245				intc_bank_read_reg(bank, (0x100 + 0x4*i));
246		for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
247			intc_context[ind].mir[i] =
248				intc_bank_read_reg(&irq_banks[0], INTC_MIR0 +
249				(0x20 * i));
250	}
251}
252
253void omap_intc_restore_context(void)
254{
255	int ind = 0, i = 0;
256
257	for (ind = 0; ind < ARRAY_SIZE(irq_banks); ind++) {
258		struct omap_irq_bank *bank = irq_banks + ind;
259		intc_bank_write_reg(intc_context[ind].sysconfig,
260					bank, INTC_SYSCONFIG);
261		intc_bank_write_reg(intc_context[ind].sysconfig,
262					bank, INTC_SYSCONFIG);
263		intc_bank_write_reg(intc_context[ind].protection,
264					bank, INTC_PROTECTION);
265		intc_bank_write_reg(intc_context[ind].idle,
266					bank, INTC_IDLE);
267		intc_bank_write_reg(intc_context[ind].threshold,
268					bank, INTC_THRESHOLD);
269		for (i = 0; i < INTCPS_NR_IRQS; i++)
270			intc_bank_write_reg(intc_context[ind].ilr[i],
271				bank, (0x100 + 0x4*i));
272		for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
273			intc_bank_write_reg(intc_context[ind].mir[i],
274				 &irq_banks[0], INTC_MIR0 + (0x20 * i));
275	}
276	/* MIRs are saved and restore with other PRCM registers */
277}
278
279void omap3_intc_suspend(void)
280{
281	/* A pending interrupt would prevent OMAP from entering suspend */
282	omap_ack_irq(0);
283}
284
285void omap3_intc_prepare_idle(void)
286{
287	/* Disable autoidle as it can stall interrupt controller */
288	intc_bank_write_reg(0, &irq_banks[0], INTC_SYSCONFIG);
289}
290
291void omap3_intc_resume_idle(void)
292{
293	/* Re-enable autoidle */
294	intc_bank_write_reg(1, &irq_banks[0], INTC_SYSCONFIG);
295}
296#endif /* CONFIG_ARCH_OMAP3 */
297