release/src-rt-6.x.4708/linux/linux-2.6.36/arch/powerpc/sysdev/mpc8xx_pic.c

   1 #include <linux/kernel.h>
   2 #include <linux/module.h>
   3 #include <linux/stddef.h>
   4 #include <linux/init.h>
   5 #include <linux/sched.h>
   6 #include <linux/signal.h>
   7 #include <linux/irq.h>
   8 #include <linux/dma-mapping.h>
   9 #include <asm/prom.h>
  10 #include <asm/irq.h>
  11 #include <asm/io.h>
  12 #include <asm/8xx_immap.h>
  13
  14 #include "mpc8xx_pic.h"
  15
  16
  17 #define PIC_VEC_SPURRIOUS      15
  18
  19 extern int cpm_get_irq(struct pt_regs *regs);
  20
  21 static struct irq_host *mpc8xx_pic_host;
  22 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
  23 static unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
  24 static sysconf8xx_t __iomem *siu_reg;
  25
  26 int cpm_get_irq(struct pt_regs *regs);
  27
  28 static void mpc8xx_unmask_irq(unsigned int virq)
  29 {
  30         int     bit, word;
  31         unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
  32
  33         bit = irq_nr & 0x1f;
  34         word = irq_nr >> 5;
  35
  36         ppc_cached_irq_mask[word] |= (1 << (31-bit));
  37         out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
  38 }
  39
  40 static void mpc8xx_mask_irq(unsigned int virq)
  41 {
  42         int     bit, word;
  43         unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
  44
  45         bit = irq_nr & 0x1f;
  46         word = irq_nr >> 5;
  47
  48         ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
  49         out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
  50 }
  51
  52 static void mpc8xx_ack(unsigned int virq)
  53 {
  54         int     bit;
  55         unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
  56
  57         bit = irq_nr & 0x1f;
  58         out_be32(&siu_reg->sc_sipend, 1 << (31-bit));
  59 }
  60
  61 static void mpc8xx_end_irq(unsigned int virq)
  62 {
  63         int bit, word;
  64         unsigned int irq_nr = (unsigned int)irq_map[virq].hwirq;
  65
  66         bit = irq_nr & 0x1f;
  67         word = irq_nr >> 5;
  68
  69         ppc_cached_irq_mask[word] |= (1 << (31-bit));
  70         out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
  71 }
  72
  73 static int mpc8xx_set_irq_type(unsigned int virq, unsigned int flow_type)
  74 {
  75         struct irq_desc *desc = irq_to_desc(virq);
  76
  77         desc->status &= ~(IRQ_TYPE_SENSE_MASK | IRQ_LEVEL);
  78         desc->status |= flow_type & IRQ_TYPE_SENSE_MASK;
  79         if (flow_type & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
  80                 desc->status |= IRQ_LEVEL;
  81
  82         if (flow_type & IRQ_TYPE_EDGE_FALLING) {
  83                 irq_hw_number_t hw = (unsigned int)irq_map[virq].hwirq;
  84                 unsigned int siel = in_be32(&siu_reg->sc_siel);
  85
  86                 /* only external IRQ senses are programmable */
  87                 if ((hw & 1) == 0) {
  88                         siel |= (0x80000000 >> hw);
  89                         out_be32(&siu_reg->sc_siel, siel);
  90                         desc->handle_irq = handle_edge_irq;
  91                 }
  92         }
  93         return 0;
  94 }
  95
  96 static struct irq_chip mpc8xx_pic = {
  97         .name = "MPC8XX SIU",
  98         .unmask = mpc8xx_unmask_irq,
  99         .mask = mpc8xx_mask_irq,
 100         .ack = mpc8xx_ack,
 101         .eoi = mpc8xx_end_irq,
 102         .set_type = mpc8xx_set_irq_type,
 103 };
 104
 105 unsigned int mpc8xx_get_irq(void)
 106 {
 107         int irq;
 108
 109         /* For MPC8xx, read the SIVEC register and shift the bits down
 110          * to get the irq number.
 111          */
 112         irq = in_be32(&siu_reg->sc_sivec) >> 26;
 113
 114         if (irq == PIC_VEC_SPURRIOUS)
 115                 irq = NO_IRQ;
 116
 117         return irq_linear_revmap(mpc8xx_pic_host, irq);
 118
 119 }
 120
 121 static int mpc8xx_pic_host_map(struct irq_host *h, unsigned int virq,
 122                           irq_hw_number_t hw)
 123 {
 124         pr_debug("mpc8xx_pic_host_map(%d, 0x%lx)\n", virq, hw);
 125
 126         /* Set default irq handle */
 127         set_irq_chip_and_handler(virq, &mpc8xx_pic, handle_level_irq);
 128         return 0;
 129 }
 130
 131
 132 static int mpc8xx_pic_host_xlate(struct irq_host *h, struct device_node *ct,
 133                             const u32 *intspec, unsigned int intsize,
 134                             irq_hw_number_t *out_hwirq, unsigned int *out_flags)
 135 {
 136         static unsigned char map_pic_senses[4] = {
 137                 IRQ_TYPE_EDGE_RISING,
 138                 IRQ_TYPE_LEVEL_LOW,
 139                 IRQ_TYPE_LEVEL_HIGH,
 140                 IRQ_TYPE_EDGE_FALLING,
 141         };
 142
 143         *out_hwirq = intspec[0];
 144         if (intsize > 1 && intspec[1] < 4)
 145                 *out_flags = map_pic_senses[intspec[1]];
 146         else
 147                 *out_flags = IRQ_TYPE_NONE;
 148
 149         return 0;
 150 }
 151
 152
 153 static struct irq_host_ops mpc8xx_pic_host_ops = {
 154         .map = mpc8xx_pic_host_map,
 155         .xlate = mpc8xx_pic_host_xlate,
 156 };
 157
 158 int mpc8xx_pic_init(void)
 159 {
 160         struct resource res;
 161         struct device_node *np;
 162         int ret;
 163
 164         np = of_find_compatible_node(NULL, NULL, "fsl,pq1-pic");
 165         if (np == NULL)
 166                 np = of_find_node_by_type(NULL, "mpc8xx-pic");
 167         if (np == NULL) {
 168                 printk(KERN_ERR "Could not find fsl,pq1-pic node\n");
 169                 return -ENOMEM;
 170         }
 171
 172         ret = of_address_to_resource(np, 0, &res);
 173         if (ret)
 174                 goto out;
 175
 176         siu_reg = ioremap(res.start, res.end - res.start + 1);
 177         if (siu_reg == NULL) {
 178                 ret = -EINVAL;
 179                 goto out;
 180         }
 181
 182         mpc8xx_pic_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR,
 183                                          64, &mpc8xx_pic_host_ops, 64);
 184         if (mpc8xx_pic_host == NULL) {
 185                 printk(KERN_ERR "MPC8xx PIC: failed to allocate irq host!\n");
 186                 ret = -ENOMEM;
 187                 goto out;
 188         }
 189         return 0;
 190
 191 out:
 192         of_node_put(np);
 193         return ret;
 194 }