arch/powerpc/sysdev/mpc8xx_pic.c

   1 #include <linux/kernel.h>
   2 #include <linux/stddef.h>
   3 #include <linux/sched.h>
   4 #include <linux/signal.h>
   5 #include <linux/irq.h>
   6 #include <linux/dma-mapping.h>
   7 #include <asm/prom.h>
   8 #include <asm/irq.h>
   9 #include <asm/io.h>
  10 #include <asm/8xx_immap.h>
  11
  12 #include "mpc8xx_pic.h"
  13
  14
  15 #define PIC_VEC_SPURRIOUS      15
  16
  17 extern int cpm_get_irq(struct pt_regs *regs);
  18
  19 static struct irq_domain *mpc8xx_pic_host;
  20 static unsigned long mpc8xx_cached_irq_mask;
  21 static sysconf8xx_t __iomem *siu_reg;
  22
  23 static inline unsigned long mpc8xx_irqd_to_bit(struct irq_data *d)
  24 {
  25         return 0x80000000 >> irqd_to_hwirq(d);
  26 }
  27
  28 static void mpc8xx_unmask_irq(struct irq_data *d)
  29 {
  30         mpc8xx_cached_irq_mask |= mpc8xx_irqd_to_bit(d);
  31         out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
  32 }
  33
  34 static void mpc8xx_mask_irq(struct irq_data *d)
  35 {
  36         mpc8xx_cached_irq_mask &= ~mpc8xx_irqd_to_bit(d);
  37         out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
  38 }
  39
  40 static void mpc8xx_ack(struct irq_data *d)
  41 {
  42         out_be32(&siu_reg->sc_sipend, mpc8xx_irqd_to_bit(d));
  43 }
  44
  45 static void mpc8xx_end_irq(struct irq_data *d)
  46 {
  47         mpc8xx_cached_irq_mask |= mpc8xx_irqd_to_bit(d);
  48         out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
  49 }
  50
  51 static int mpc8xx_set_irq_type(struct irq_data *d, unsigned int flow_type)
  52 {
  53         /* only external IRQ senses are programmable */
  54         if ((flow_type & IRQ_TYPE_EDGE_FALLING) && !(irqd_to_hwirq(d) & 1)) {
  55                 unsigned int siel = in_be32(&siu_reg->sc_siel);
  56                 siel |= mpc8xx_irqd_to_bit(d);
  57                 out_be32(&siu_reg->sc_siel, siel);
  58                 irq_set_handler_locked(d, handle_edge_irq);
  59         }
  60         return 0;
  61 }
  62
  63 static struct irq_chip mpc8xx_pic = {
  64         .name = "8XX SIU",
  65         .irq_unmask = mpc8xx_unmask_irq,
  66         .irq_mask = mpc8xx_mask_irq,
  67         .irq_ack = mpc8xx_ack,
  68         .irq_eoi = mpc8xx_end_irq,
  69         .irq_set_type = mpc8xx_set_irq_type,
  70 };
  71
  72 unsigned int mpc8xx_get_irq(void)
  73 {
  74         int irq;
  75
  76         /* For MPC8xx, read the SIVEC register and shift the bits down
  77          * to get the irq number.
  78          */
  79         irq = in_be32(&siu_reg->sc_sivec) >> 26;
  80
  81         if (irq == PIC_VEC_SPURRIOUS)
  82                 return 0;
  83
  84         return irq_linear_revmap(mpc8xx_pic_host, irq);
  85
  86 }
  87
  88 static int mpc8xx_pic_host_map(struct irq_domain *h, unsigned int virq,
  89                           irq_hw_number_t hw)
  90 {
  91         pr_debug("mpc8xx_pic_host_map(%d, 0x%lx)\n", virq, hw);
  92
  93         /* Set default irq handle */
  94         irq_set_chip_and_handler(virq, &mpc8xx_pic, handle_level_irq);
  95         return 0;
  96 }
  97
  98
  99 static int mpc8xx_pic_host_xlate(struct irq_domain *h, struct device_node *ct,
 100                             const u32 *intspec, unsigned int intsize,
 101                             irq_hw_number_t *out_hwirq, unsigned int *out_flags)
 102 {
 103         static unsigned char map_pic_senses[4] = {
 104                 IRQ_TYPE_EDGE_RISING,
 105                 IRQ_TYPE_LEVEL_LOW,
 106                 IRQ_TYPE_LEVEL_HIGH,
 107                 IRQ_TYPE_EDGE_FALLING,
 108         };
 109
 110         if (intspec[0] > 0x1f)
 111                 return 0;
 112
 113         *out_hwirq = intspec[0];
 114         if (intsize > 1 && intspec[1] < 4)
 115                 *out_flags = map_pic_senses[intspec[1]];
 116         else
 117                 *out_flags = IRQ_TYPE_NONE;
 118
 119         return 0;
 120 }
 121
 122
 123 static const struct irq_domain_ops mpc8xx_pic_host_ops = {
 124         .map = mpc8xx_pic_host_map,
 125         .xlate = mpc8xx_pic_host_xlate,
 126 };
 127
 128 int mpc8xx_pic_init(void)
 129 {
 130         struct resource res;
 131         struct device_node *np;
 132         int ret;
 133
 134         np = of_find_compatible_node(NULL, NULL, "fsl,pq1-pic");
 135         if (np == NULL)
 136                 np = of_find_node_by_type(NULL, "mpc8xx-pic");
 137         if (np == NULL) {
 138                 printk(KERN_ERR "Could not find fsl,pq1-pic node\n");
 139                 return -ENOMEM;
 140         }
 141
 142         ret = of_address_to_resource(np, 0, &res);
 143         if (ret)
 144                 goto out;
 145
 146         siu_reg = ioremap(res.start, resource_size(&res));
 147         if (siu_reg == NULL) {
 148                 ret = -EINVAL;
 149                 goto out;
 150         }
 151
 152         mpc8xx_pic_host = irq_domain_add_linear(np, 64, &mpc8xx_pic_host_ops, NULL);
 153         if (mpc8xx_pic_host == NULL) {
 154                 printk(KERN_ERR "MPC8xx PIC: failed to allocate irq host!\n");
 155                 ret = -ENOMEM;
 156                 goto out;
 157         }
 158         return 0;
 159
 160 out:
 161         of_node_put(np);
 162         return ret;
 163 }