Blame view

kernel/linux-imx6_3.14.28/arch/mips/dec/ioasic-irq.c 3.19 KB
6b13f685e   김민수   BSP 최초 추가
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
  /*
   *	DEC I/O ASIC interrupts.
   *
   *	Copyright (c) 2002, 2003, 2013  Maciej W. Rozycki
   *
   *	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/irq.h>
  #include <linux/types.h>
  
  #include <asm/dec/ioasic.h>
  #include <asm/dec/ioasic_addrs.h>
  #include <asm/dec/ioasic_ints.h>
  
  static int ioasic_irq_base;
  
  static void unmask_ioasic_irq(struct irq_data *d)
  {
  	u32 simr;
  
  	simr = ioasic_read(IO_REG_SIMR);
  	simr |= (1 << (d->irq - ioasic_irq_base));
  	ioasic_write(IO_REG_SIMR, simr);
  }
  
  static void mask_ioasic_irq(struct irq_data *d)
  {
  	u32 simr;
  
  	simr = ioasic_read(IO_REG_SIMR);
  	simr &= ~(1 << (d->irq - ioasic_irq_base));
  	ioasic_write(IO_REG_SIMR, simr);
  }
  
  static void ack_ioasic_irq(struct irq_data *d)
  {
  	mask_ioasic_irq(d);
  	fast_iob();
  }
  
  static struct irq_chip ioasic_irq_type = {
  	.name = "IO-ASIC",
  	.irq_ack = ack_ioasic_irq,
  	.irq_mask = mask_ioasic_irq,
  	.irq_mask_ack = ack_ioasic_irq,
  	.irq_unmask = unmask_ioasic_irq,
  };
  
  static void clear_ioasic_dma_irq(struct irq_data *d)
  {
  	u32 sir;
  
  	sir = ~(1 << (d->irq - ioasic_irq_base));
  	ioasic_write(IO_REG_SIR, sir);
  	fast_iob();
  }
  
  static struct irq_chip ioasic_dma_irq_type = {
  	.name = "IO-ASIC-DMA",
  	.irq_ack = clear_ioasic_dma_irq,
  	.irq_mask = mask_ioasic_irq,
  	.irq_unmask = unmask_ioasic_irq,
  	.irq_eoi = clear_ioasic_dma_irq,
  };
  
  /*
   * I/O ASIC implements two kinds of DMA interrupts, informational and
   * error interrupts.
   *
   * The formers do not stop DMA and should be cleared as soon as possible
   * so that if they retrigger before the handler has completed, usually as
   * a side effect of actions taken by the handler, then they are reissued.
   * These use the `handle_edge_irq' handler that clears the request right
   * away.
   *
   * The latters stop DMA and do not resume it until the interrupt has been
   * cleared.  This cannot be done until after a corrective action has been
   * taken and this also means they will not retrigger.  Therefore they use
   * the `handle_fasteoi_irq' handler that only clears the request on the
   * way out.  Because MIPS processor interrupt inputs, one of which the I/O
   * ASIC is cascaded to, are level-triggered it is recommended that error
   * DMA interrupt action handlers are registered with the IRQF_ONESHOT flag
   * set so that they are run with the interrupt line masked.
   *
   * This mask has `1' bits in the positions of informational interrupts.
   */
  #define IO_IRQ_DMA_INFO							\
  	(IO_IRQ_MASK(IO_INR_SCC0A_RXDMA) |				\
  	 IO_IRQ_MASK(IO_INR_SCC1A_RXDMA) |				\
  	 IO_IRQ_MASK(IO_INR_ISDN_TXDMA) |				\
  	 IO_IRQ_MASK(IO_INR_ISDN_RXDMA) |				\
  	 IO_IRQ_MASK(IO_INR_ASC_DMA))
  
  void __init init_ioasic_irqs(int base)
  {
  	int i;
  
  	/* Mask interrupts. */
  	ioasic_write(IO_REG_SIMR, 0);
  	fast_iob();
  
  	for (i = base; i < base + IO_INR_DMA; i++)
  		irq_set_chip_and_handler(i, &ioasic_irq_type,
  					 handle_level_irq);
  	for (; i < base + IO_IRQ_LINES; i++)
  		irq_set_chip_and_handler(i, &ioasic_dma_irq_type,
  					 1 << (i - base) & IO_IRQ_DMA_INFO ?
  					 handle_edge_irq : handle_fasteoi_irq);
  
  	ioasic_irq_base = base;
  }