aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/pmcs-msp71xx/msp_irq_cic.c
blob: 1207ec4dfb77021a6a114d776684ccfbe696ea00 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/*
 * Copyright 2010 PMC-Sierra, Inc, derived from irq_cpu.c
 *
 * This file define the irq handler for MSP CIC subsystem interrupts.
 *
 * This program is free software; you can redistribute	it and/or modify it
 * under  the terms of	the GNU General	 Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/bitops.h>
#include <linux/irq.h>

#include <asm/mipsregs.h>

#include <msp_cic_int.h>
#include <msp_regs.h>

/*
 * External API
 */
extern void msp_per_irq_init(void);
extern void msp_per_irq_dispatch(void);


/*
 * Convenience Macro.  Should be somewhere generic.
 */
#define get_current_vpe()   \
	((read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & TCBIND_CURVPE)

#ifdef CONFIG_SMP

#define LOCK_VPE(flags, mtflags) \
do {				\
	local_irq_save(flags);	\
	mtflags = dmt();	\
} while (0)

#define UNLOCK_VPE(flags, mtflags) \
do {				\
	emt(mtflags);		\
	local_irq_restore(flags);\
} while (0)

#define LOCK_CORE(flags, mtflags) \
do {				\
	local_irq_save(flags);	\
	mtflags = dvpe();	\
} while (0)

#define UNLOCK_CORE(flags, mtflags)		\
do {				\
	evpe(mtflags);		\
	local_irq_restore(flags);\
} while (0)

#else

#define LOCK_VPE(flags, mtflags)
#define UNLOCK_VPE(flags, mtflags)
#endif

/* ensure writes to cic are completed */
static inline void cic_wmb(void)
{
	const volatile void __iomem *cic_mem = CIC_VPE0_MSK_REG;
	volatile u32 dummy_read;

	wmb();
	dummy_read = __raw_readl(cic_mem);
	dummy_read++;
}

static void unmask_cic_irq(struct irq_data *d)
{
	volatile u32   *cic_msk_reg = CIC_VPE0_MSK_REG;
	int vpe;
#ifdef CONFIG_SMP
	unsigned int mtflags;
	unsigned long  flags;

	/*
	* Make sure we have IRQ affinity.  It may have changed while
	* we were processing the IRQ.
	*/
	if (!cpumask_test_cpu(smp_processor_id(), d->affinity))
		return;
#endif

	vpe = get_current_vpe();
	LOCK_VPE(flags, mtflags);
	cic_msk_reg[vpe] |= (1 << (d->irq - MSP_CIC_INTBASE));
	UNLOCK_VPE(flags, mtflags);
	cic_wmb();
}

static void mask_cic_irq(struct irq_data *d)
{
	volatile u32 *cic_msk_reg = CIC_VPE0_MSK_REG;
	int	vpe = get_current_vpe();
#ifdef CONFIG_SMP
	unsigned long flags, mtflags;
#endif
	LOCK_VPE(flags, mtflags);
	cic_msk_reg[vpe] &= ~(1 << (d->irq - MSP_CIC_INTBASE));
	UNLOCK_VPE(flags, mtflags);
	cic_wmb();
}
static void msp_cic_irq_ack(struct irq_data *d)
{
	mask_cic_irq(d);
	/*
	* Only really necessary for 18, 16-14 and sometimes 3:0
	* (since these can be edge sensitive) but it doesn't
	* hurt for the others
	*/
	*CIC_STS_REG = (1 << (d->irq - MSP_CIC_INTBASE));
}

/* Note: Limiting to VSMP.  */

#ifdef CONFIG_MIPS_MT_SMP
static int msp_cic_irq_set_affinity(struct irq_data *d,
				    const struct cpumask *cpumask, bool force)
{
	int cpu;
	unsigned long flags;
	unsigned int  mtflags;
	unsigned long imask = (1 << (d->irq - MSP_CIC_INTBASE));
	volatile u32 *cic_mask = (volatile u32 *)CIC_VPE0_MSK_REG;

	/* timer balancing should be disabled in kernel code */
	BUG_ON(d->irq == MSP_INT_VPE0_TIMER || d->irq == MSP_INT_VPE1_TIMER);

	LOCK_CORE(flags, mtflags);
	/* enable if any of each VPE's TCs require this IRQ */
	for_each_online_cpu(cpu) {
		if (cpumask_test_cpu(cpu, cpumask))
			cic_mask[cpu] |= imask;
		else
			cic_mask[cpu] &= ~imask;

	}

	UNLOCK_CORE(flags, mtflags);
	return 0;

}
#endif

static struct irq_chip msp_cic_irq_controller = {
	.name = "MSP_CIC",
	.irq_mask = mask_cic_irq,
	.irq_mask_ack = msp_cic_irq_ack,
	.irq_unmask = unmask_cic_irq,
	.irq_ack = msp_cic_irq_ack,
#ifdef CONFIG_MIPS_MT_SMP
	.irq_set_affinity = msp_cic_irq_set_affinity,
#endif
};

void __init msp_cic_irq_init(void)
{
	int i;
	/* Mask/clear interrupts. */
	*CIC_VPE0_MSK_REG = 0x00000000;
	*CIC_VPE1_MSK_REG = 0x00000000;
	*CIC_STS_REG	  = 0xFFFFFFFF;
	/*
	* The MSP7120 RG and EVBD boards use IRQ[6:4] for PCI.
	* These inputs map to EXT_INT_POL[6:4] inside the CIC.
	* They are to be active low, level sensitive.
	*/
	*CIC_EXT_CFG_REG &= 0xFFFF8F8F;

	/* initialize all the IRQ descriptors */
	for (i = MSP_CIC_INTBASE ; i < MSP_CIC_INTBASE + 32 ; i++) {
		irq_set_chip_and_handler(i, &msp_cic_irq_controller,
					 handle_level_irq);
	}

	/* Initialize the PER interrupt sub-system */
	 msp_per_irq_init();
}

/* CIC masked by CIC vector processing before dispatch called */
void msp_cic_irq_dispatch(void)
{
	volatile u32	*cic_msk_reg = (volatile u32 *)CIC_VPE0_MSK_REG;
	u32	cic_mask;
	u32	 pending;
	int	cic_status = *CIC_STS_REG;
	cic_mask = cic_msk_reg[get_current_vpe()];
	pending = cic_status & cic_mask;
	if (pending & (1 << (MSP_INT_VPE0_TIMER - MSP_CIC_INTBASE))) {
		do_IRQ(MSP_INT_VPE0_TIMER);
	} else if (pending & (1 << (MSP_INT_VPE1_TIMER - MSP_CIC_INTBASE))) {
		do_IRQ(MSP_INT_VPE1_TIMER);
	} else if (pending & (1 << (MSP_INT_PER - MSP_CIC_INTBASE))) {
		msp_per_irq_dispatch();
	} else if (pending) {
		do_IRQ(ffs(pending) + MSP_CIC_INTBASE - 1);
	} else{
		spurious_interrupt();
	}
}