Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
awilliam
GitHub Repository: awilliam/linux-vfio
 Path: blob/master/arch/mn10300/unit-asb2364/irq-fpga.c
10817 views
1
/* ASB2364 FPGA interrupt multiplexing

2
 *

3
 * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.

4
 * Written by David Howells ([email protected])

5
 *

6
 * This program is free software; you can redistribute it and/or

7
 * modify it under the terms of the GNU General Public Licence

8
 * as published by the Free Software Foundation; either version

9
 * 2 of the Licence, or (at your option) any later version.

10
 */

11


12
#include <linux/interrupt.h>

13
#include <linux/init.h>

14
#include <linux/irq.h>

15
#include <unit/fpga-regs.h>

16


17
/*

18
 * FPGA PIC operations

19
 */

20
static void asb2364_fpga_mask(struct irq_data *d)

21
{

22
	ASB2364_FPGA_REG_MASK(d->irq - NR_CPU_IRQS) = 0x0001;

23
	SyncExBus();

24
}

25


26
static void asb2364_fpga_ack(struct irq_data *d)

27
{

28
	ASB2364_FPGA_REG_IRQ(d->irq - NR_CPU_IRQS) = 0x0001;

29
	SyncExBus();

30
}

31


32
static void asb2364_fpga_mask_ack(struct irq_data *d)

33
{

34
	ASB2364_FPGA_REG_MASK(d->irq - NR_CPU_IRQS) = 0x0001;

35
	SyncExBus();

36
	ASB2364_FPGA_REG_IRQ(d->irq - NR_CPU_IRQS) = 0x0001;

37
	SyncExBus();

38
}

39


40
static void asb2364_fpga_unmask(struct irq_data *d)

41
{

42
	ASB2364_FPGA_REG_MASK(d->irq - NR_CPU_IRQS) = 0x0000;

43
	SyncExBus();

44
}

45


46
static struct irq_chip asb2364_fpga_pic = {

47
	.name		= "fpga",

48
	.irq_ack	= asb2364_fpga_ack,

49
	.irq_mask	= asb2364_fpga_mask,

50
	.irq_mask_ack	= asb2364_fpga_mask_ack,

51
	.irq_unmask	= asb2364_fpga_unmask,

52
};

53


54
/*

55
 * FPGA PIC interrupt handler

56
 */

57
static irqreturn_t fpga_interrupt(int irq, void *_mask)

58
{

59
	if ((ASB2364_FPGA_REG_IRQ_LAN  & 0x0001) != 0x0001)

60
		generic_handle_irq(FPGA_LAN_IRQ);

61
	if ((ASB2364_FPGA_REG_IRQ_UART & 0x0001) != 0x0001)

62
		generic_handle_irq(FPGA_UART_IRQ);

63
	if ((ASB2364_FPGA_REG_IRQ_I2C  & 0x0001) != 0x0001)

64
		generic_handle_irq(FPGA_I2C_IRQ);

65
	if ((ASB2364_FPGA_REG_IRQ_USB  & 0x0001) != 0x0001)

66
		generic_handle_irq(FPGA_USB_IRQ);

67
	if ((ASB2364_FPGA_REG_IRQ_FPGA & 0x0001) != 0x0001)

68
		generic_handle_irq(FPGA_FPGA_IRQ);

69


70
	return IRQ_HANDLED;

71
}

72


73
/*

74
 * Define an interrupt action for each FPGA PIC output

75
 */

76
static struct irqaction fpga_irq[]  = {

77
	[0] = {

78
		.handler	= fpga_interrupt,

79
		.flags		= IRQF_DISABLED | IRQF_SHARED,

80
		.name		= "fpga",

81
	},

82
};

83


84
/*

85
 * Initialise the FPGA's PIC

86
 */

87
void __init irq_fpga_init(void)

88
{

89
	int irq;

90


91
	ASB2364_FPGA_REG_MASK_LAN  = 0x0001;

92
	SyncExBus();

93
	ASB2364_FPGA_REG_MASK_UART = 0x0001;

94
	SyncExBus();

95
	ASB2364_FPGA_REG_MASK_I2C  = 0x0001;

96
	SyncExBus();

97
	ASB2364_FPGA_REG_MASK_USB  = 0x0001;

98
	SyncExBus();

99
	ASB2364_FPGA_REG_MASK_FPGA = 0x0001;

100
	SyncExBus();

101


102
	for (irq = NR_CPU_IRQS; irq < NR_IRQS; irq++)

103
		irq_set_chip_and_handler(irq, &asb2364_fpga_pic,

104
					 handle_level_irq);

105


106
	/* the FPGA drives the XIRQ1 input on the CPU PIC */

107
	setup_irq(XIRQ1, &fpga_irq[0]);

108
}

109


110