aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/pmc-sierra/msp71xx/msp_irq_per.c
blob: 72bcd70d2ddf89d2ee72091b36c07d80b1d5cc3a (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
/*
 * Copyright 2010 PMC-Sierra, Inc, derived from irq_cpu.c
 *
 * This file define the irq handler for MSP PER 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/spinlock.h>
#include <linux/bitops.h>

#include <asm/mipsregs.h>
#include <asm/system.h>

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


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

#ifdef CONFIG_SMP
/*
 * The PER registers must be protected from concurrent access.
 */

static DEFINE_SPINLOCK(per_lock);
#endif

/* ensure writes to per are completed */

static inline void per_wmb(void)
{
	const volatile void __iomem *per_mem = PER_INT_MSK_REG;
	volatile u32 dummy_read;

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

static inline void unmask_per_irq(unsigned int irq)
{
#ifdef CONFIG_SMP
	unsigned long flags;
	spin_lock_irqsave(&per_lock, flags);
	*PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
	spin_unlock_irqrestore(&per_lock, flags);
#else
	*PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
#endif
	per_wmb();
}

static inline void mask_per_irq(unsigned int irq)
{
#ifdef CONFIG_SMP
	unsigned long flags;
	spin_lock_irqsave(&per_lock, flags);
	*PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
	spin_unlock_irqrestore(&per_lock, flags);
#else
	*PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
#endif
	per_wmb();
}

static inline void msp_per_irq_enable(unsigned int irq)
{
	unmask_per_irq(irq);
}

static inline void msp_per_irq_disable(unsigned int irq)
{
	 mask_per_irq(irq);
}

static unsigned int msp_per_irq_startup(unsigned int irq)
{
	msp_per_irq_enable(irq);
	return 0;
}

#define    msp_per_irq_shutdown    msp_per_irq_disable

static inline void msp_per_irq_ack(unsigned int irq)
{
	mask_per_irq(irq);
	/*
	 * In the PER interrupt controller, only bits 11 and 10
	 * are write-to-clear, (SPI TX complete, SPI RX complete).
	 * It does nothing for any others.
	 */

	*PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));

	/* Re-enable the CIC cascaded interrupt and return */
	irq_desc[MSP_INT_CIC].chip->end(MSP_INT_CIC);
}

static void msp_per_irq_end(unsigned int irq)
{
	if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
		unmask_per_irq(irq);
}

#ifdef CONFIG_SMP
static inline int msp_per_irq_set_affinity(unsigned int irq,
				const struct cpumask *affinity)
{
	unsigned long flags;
	/*
	 * Calls to ack, end, startup, enable are spinlocked in setup_irq and
	 * __do_IRQ.Callers of this function do not spinlock,so we need to
	 * do so ourselves.
	 */
	raw_spin_lock_irqsave(&irq_desc[irq].lock, flags);
	msp_per_irq_enable(irq);
	raw_spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
	return 0;

}
#endif

static struct irq_chip msp_per_irq_controller = {
	.name = "MSP_PER",
	.startup = msp_per_irq_startup,
	.shutdown = msp_per_irq_shutdown,
	.enable = msp_per_irq_enable,
	.disable = msp_per_irq_disable,
#ifdef CONFIG_SMP
	.set_affinity = msp_per_irq_set_affinity,
#endif
	.ack = msp_per_irq_ack,
	.end = msp_per_irq_end,
};

void __init msp_per_irq_init(void)
{
	int i;
	/* Mask/clear interrupts. */
	*PER_INT_MSK_REG  = 0x00000000;
	*PER_INT_STS_REG  = 0xFFFFFFFF;
	/* initialize all the IRQ descriptors */
	for (i = MSP_PER_INTBASE; i < MSP_PER_INTBASE + 32; i++) {
		irq_desc[i].status = IRQ_DISABLED;
		irq_desc[i].action = NULL;
		irq_desc[i].depth = 1;
		irq_desc[i].chip = &msp_per_irq_controller;
#ifdef CONFIG_MIPS_MT_SMTC
		irq_hwmask[i] = C_IRQ4;
#endif
	}
}

void msp_per_irq_dispatch(void)
{
	u32	per_mask = *PER_INT_MSK_REG;
	u32	per_status = *PER_INT_STS_REG;
	u32	pending;

	pending = per_status & per_mask;
	if (pending) {
		do_IRQ(ffs(pending) + MSP_PER_INTBASE - 1);
	} else {
		spurious_interrupt();
	/* Re-enable the CIC cascaded interrupt and return */
	irq_desc[MSP_INT_CIC].chip->end(MSP_INT_CIC);
	}
}