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                128
  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
  36         gc = irq_alloc_generic_chip("SIRFINTC", 1, irq_start, base, handle_level_irq);
  37         ct = gc->chip_types;
  38
  39         ct->chip.irq_mask = irq_gc_mask_clr_bit;
  40         ct->chip.irq_unmask = irq_gc_mask_set_bit;
  41         ct->regs.mask = SIRFSOC_INT_RISC_MASK0;
  42
  43         irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST, 0);
  44 }
  45
  46 static asmlinkage void __exception_irq_entry sirfsoc_handle_irq(struct pt_regs *regs)
  47 {
  48         void __iomem *base = sirfsoc_irqdomain->host_data;
  49         u32 irqstat, irqnr;
  50
  51         irqstat = readl_relaxed(base + SIRFSOC_INIT_IRQ_ID);
  52         irqnr = irq_find_mapping(sirfsoc_irqdomain, irqstat & 0xff);
  53
  54         handle_IRQ(irqnr, regs);
  55 }
  56
  57 static int __init sirfsoc_irq_init(struct device_node *np, struct device_node *parent)
  58 {
  59         void __iomem *base = of_iomap(np, 0);
  60         if (!base)
  61                 panic("unable to map intc cpu registers\n");
  62
  63         /* using legacy because irqchip_generic does not work with linear */
  64         sirfsoc_irqdomain = irq_domain_add_legacy(np, SIRFSOC_NUM_IRQS, 0, 0,
  65                                  &irq_domain_simple_ops, base);
  66
  67         sirfsoc_alloc_gc(base, 0, 32);
  68         sirfsoc_alloc_gc(base + 4, 32, SIRFSOC_NUM_IRQS - 32);
  69
  70         writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL0);
  71         writel_relaxed(0, base + SIRFSOC_INT_RISC_LEVEL1);
  72
  73         writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK0);
  74         writel_relaxed(0, base + SIRFSOC_INT_RISC_MASK1);
  75
  76         set_handle_irq(sirfsoc_handle_irq);
  77
  78         return 0;
  79 }
  80 IRQCHIP_DECLARE(sirfsoc_intc, "sirf,prima2-intc", sirfsoc_irq_init);
  81
  82 struct sirfsoc_irq_status {
  83         u32 mask0;
  84         u32 mask1;
  85         u32 level0;
  86         u32 level1;
  87 };
  88
  89 static struct sirfsoc_irq_status sirfsoc_irq_st;
  90
  91 static int sirfsoc_irq_suspend(void)
  92 {
  93         void __iomem *base = sirfsoc_irqdomain->host_data;
  94
  95         sirfsoc_irq_st.mask0 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK0);
  96         sirfsoc_irq_st.mask1 = readl_relaxed(base + SIRFSOC_INT_RISC_MASK1);
  97         sirfsoc_irq_st.level0 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL0);
  98         sirfsoc_irq_st.level1 = readl_relaxed(base + SIRFSOC_INT_RISC_LEVEL1);
  99
 100         return 0;
 101 }
 102
 103 static void sirfsoc_irq_resume(void)
 104 {
 105         void __iomem *base = sirfsoc_irqdomain->host_data;
 106
 107         writel_relaxed(sirfsoc_irq_st.mask0, base + SIRFSOC_INT_RISC_MASK0);
 108         writel_relaxed(sirfsoc_irq_st.mask1, base + SIRFSOC_INT_RISC_MASK1);
 109         writel_relaxed(sirfsoc_irq_st.level0, base + SIRFSOC_INT_RISC_LEVEL0);
 110         writel_relaxed(sirfsoc_irq_st.level1, base + SIRFSOC_INT_RISC_LEVEL1);
 111 }
 112
 113 static struct syscore_ops sirfsoc_irq_syscore_ops = {
 114         .suspend        = sirfsoc_irq_suspend,
 115         .resume         = sirfsoc_irq_resume,
 116 };
 117
 118 static int __init sirfsoc_irq_pm_init(void)
 119 {
 120         if (!sirfsoc_irqdomain)
 121                 return 0;
 122
 123         register_syscore_ops(&sirfsoc_irq_syscore_ops);
 124         return 0;
 125 }
 126 device_initcall(sirfsoc_irq_pm_init);