kernel/drivers/irqchip/irq-sirfsoc.c

   1 /*
   2  * interrupt controller support for CSR SiRFprimaII
   3  *
   4  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
   5  *
   6  * Licensed under GPLv2 or later.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/io.h>
  11 #include <linux/irq.h>
  12 #include <linux/of.h>
  13 #include <linux/of_address.h>
  14 #include <linux/irqdomain.h>
  15 #include <linux/syscore_ops.h>
  16 #include <asm/mach/irq.h>
  17 #include <asm/exception.h>
  18 #include "irqchip.h"
  19
  20 #define SIRFSOC_INT_RISC_MASK0          0x0018
  21 #define SIRFSOC_INT_RISC_MASK1          0x001C
  22 #define SIRFSOC_INT_RISC_LEVEL0         0x0020
  23 #define SIRFSOC_INT_RISC_LEVEL1         0x0024
  24 #define SIRFSOC_INIT_IRQ_ID             0x0038
  25
  26 #define SIRFSOC_NUM_IRQS                64
  27
  28 static struct irq_domain *sirfsoc_irqdomain;
  29
  30 static __init void
  31 sirfsoc_alloc_gc(void __iomem *base, unsigned int irq_start, unsigned int num)
  32 {
  33         struct irq_chip_generic *gc;
  34         struct irq_chip_type *ct;
  35         int ret;
  36         unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
  37         unsigned int set = IRQ_LEVEL;
  38
  39         ret = irq_alloc_domain_generic_chips(sirfsoc_irqdomain, num, 1, "irq_sirfsoc",
  40                 handle_level_irq, clr, set, IRQ_GC_INIT_MASK_CACHE);
  41
  42         gc = irq_get_domain_generic_chip(sirfsoc_irqdomain, irq_start);
  43         gc->reg_base = base;
  44         ct = gc->chip_types;
  45         ct->chip.irq_mask = irq_gc_mask_clr_bit;
  46         ct->chip.irq_unmask = irq_gc_mask_set_bit;
  47         ct->regs.mask = SIRFSOC_INT_RISC_MASK0;
  48 }
  49
  50 static void __exception_irq_entry sirfsoc_handle_irq(struct pt_regs *regs)
  51 {
  52         void __iomem *base = sirfsoc_irqdomain->host_data;
  53         u32 irqstat;
  54
  55         irqstat = readl_relaxed(base + SIRFSOC_INIT_IRQ_ID);
  56         handle_domain_irq(sirfsoc_irqdomain, irqstat & 0xff, regs);
  57 }
  58
  59 static int __init sirfsoc_irq_init(struct device_node *np,
  60         struct device_node *parent)
  61 {
  62         void __iomem *base = of_iomap(np, 0);
  63         if (!base)
  64                 panic("unable to map intc cpu registers\n");
  65
  66         sirfsoc_irqdomain = irq_domain_add_linear(np, SIRFSOC_NUM_IRQS,
  67                 &irq_generic_chip_ops, base);
  68
  69         sirfsoc_alloc_gc(base, 0, 32);
  70         sirfsoc_alloc_gc(base + 4, 32, SIRFSOC_NUM_IRQS - 32);
  71
  72         writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL0);
  73         writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL1);
  74
  75         writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK0);
  76         writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK1);
  77
  78         set_handle_irq(sirfsoc_handle_irq);
  79
  80         return 0;
  81 }
  82 IRQCHIP_DECLARE(sirfsoc_intc, "sirf,prima2-intc", sirfsoc_irq_init);
  83
  84 struct sirfsoc_irq_status {
  85         u32 mask0;
  86         u32 mask1;
  87         u32 level0;
  88         u32 level1;
  89 };
  90
  91 static struct sirfsoc_irq_status sirfsoc_irq_st;
  92
  93 static int sirfsoc_irq_suspend(void)
  94 {
  95         void __iomem *base = sirfsoc_irqdomain->host_data;
  96
  97         sirfsoc_irq_st.mask0 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK0);
  98         sirfsoc_irq_st.mask1 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK1);
  99         sirfsoc_irq_st.level0 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL0);
 100         sirfsoc_irq_st.level1 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL1);
 101
 102         return 0;
 103 }
 104
 105 static void sirfsoc_irq_resume(void)
 106 {
 107         void __iomem *base = sirfsoc_irqdomain->host_data;
 108
 109         writel_relaxed(sirfsoc_irq_st.mask0, base + SIRFSOC_INT_RISC_MASK0);
 110         writel_relaxed(sirfsoc_irq_st.mask1, base + SIRFSOC_INT_RISC_MASK1);
 111         writel_relaxed(sirfsoc_irq_st.level0, base + SIRFSOC_INT_RISC_LEVEL0);
 112         writel_relaxed(sirfsoc_irq_st.level1, base + SIRFSOC_INT_RISC_LEVEL1);
 113 }
 114
 115 static struct syscore_ops sirfsoc_irq_syscore_ops = {
 116         .suspend        = sirfsoc_irq_suspend,
 117         .resume         = sirfsoc_irq_resume,
 118 };
 119
 120 static int __init sirfsoc_irq_pm_init(void)
 121 {
 122         if (!sirfsoc_irqdomain)
 123                 return 0;
 124
 125         register_syscore_ops(&sirfsoc_irq_syscore_ops);
 126         return 0;
 127 }
 128 device_initcall(sirfsoc_irq_pm_init);