arch/powerpc/platforms/cell/beat_interrupt.c

   1 /*
   2  * Celleb/Beat Interrupt controller
   3  *
   4  * (C) Copyright 2006-2007 TOSHIBA CORPORATION
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/irq.h>
  24 #include <linux/percpu.h>
  25 #include <linux/types.h>
  26
  27 #include <asm/machdep.h>
  28
  29 #include "beat_interrupt.h"
  30 #include "beat_wrapper.h"
  31
  32 #define MAX_IRQS        NR_IRQS
  33 static DEFINE_RAW_SPINLOCK(beatic_irq_mask_lock);
  34 static uint64_t beatic_irq_mask_enable[(MAX_IRQS+255)/64];
  35 static uint64_t beatic_irq_mask_ack[(MAX_IRQS+255)/64];
  36
  37 static struct irq_host *beatic_host;
  38
  39 /*
  40  * In this implementation, "virq" == "IRQ plug number",
  41  * "(irq_hw_number_t)hwirq" == "IRQ outlet number".
  42  */
  43
  44 /* assumption: locked */
  45 static inline void beatic_update_irq_mask(unsigned int irq_plug)
  46 {
  47         int off;
  48         unsigned long masks[4];
  49
  50         off = (irq_plug / 256) * 4;
  51         masks[0] = beatic_irq_mask_enable[off + 0]
  52                 & beatic_irq_mask_ack[off + 0];
  53         masks[1] = beatic_irq_mask_enable[off + 1]
  54                 & beatic_irq_mask_ack[off + 1];
  55         masks[2] = beatic_irq_mask_enable[off + 2]
  56                 & beatic_irq_mask_ack[off + 2];
  57         masks[3] = beatic_irq_mask_enable[off + 3]
  58                 & beatic_irq_mask_ack[off + 3];
  59         if (beat_set_interrupt_mask(irq_plug&~255UL,
  60                 masks[0], masks[1], masks[2], masks[3]) != 0)
  61                 panic("Failed to set mask IRQ!");
  62 }
  63
  64 static void beatic_mask_irq(struct irq_data *d)
  65 {
  66         unsigned long flags;
  67
  68         raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
  69         beatic_irq_mask_enable[d->irq/64] &= ~(1UL << (63 - (d->irq%64)));
  70         beatic_update_irq_mask(d->irq);
  71         raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
  72 }
  73
  74 static void beatic_unmask_irq(struct irq_data *d)
  75 {
  76         unsigned long flags;
  77
  78         raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
  79         beatic_irq_mask_enable[d->irq/64] |= 1UL << (63 - (d->irq%64));
  80         beatic_update_irq_mask(d->irq);
  81         raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
  82 }
  83
  84 static void beatic_ack_irq(struct irq_data *d)
  85 {
  86         unsigned long flags;
  87
  88         raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
  89         beatic_irq_mask_ack[d->irq/64] &= ~(1UL << (63 - (d->irq%64)));
  90         beatic_update_irq_mask(d->irq);
  91         raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
  92 }
  93
  94 static void beatic_end_irq(struct irq_data *d)
  95 {
  96         s64 err;
  97         unsigned long flags;
  98
  99         err = beat_downcount_of_interrupt(d->irq);
 100         if (err != 0) {
 101                 if ((err & 0xFFFFFFFF) != 0xFFFFFFF5) /* -11: wrong state */
 102                         panic("Failed to downcount IRQ! Error = %16llx", err);
 103
 104                 printk(KERN_ERR "IRQ over-downcounted, plug %d\n", d->irq);
 105         }
 106         raw_spin_lock_irqsave(&beatic_irq_mask_lock, flags);
 107         beatic_irq_mask_ack[d->irq/64] |= 1UL << (63 - (d->irq%64));
 108         beatic_update_irq_mask(d->irq);
 109         raw_spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
 110 }
 111
 112 static struct irq_chip beatic_pic = {
 113         .name = "CELL-BEAT",
 114         .irq_unmask = beatic_unmask_irq,
 115         .irq_mask = beatic_mask_irq,
 116         .irq_eoi = beatic_end_irq,
 117 };
 118
 119 /*
 120  * Dispose binding hardware IRQ number (hw) and Virtuql IRQ number (virq),
 121  * update flags.
 122  *
 123  * Note that the number (virq) is already assigned at upper layer.
 124  */
 125 static void beatic_pic_host_unmap(struct irq_host *h, unsigned int virq)
 126 {
 127         beat_destruct_irq_plug(virq);
 128 }
 129
 130 /*
 131  * Create or update binding hardware IRQ number (hw) and Virtuql
 132  * IRQ number (virq). This is called only once for a given mapping.
 133  *
 134  * Note that the number (virq) is already assigned at upper layer.
 135  */
 136 static int beatic_pic_host_map(struct irq_host *h, unsigned int virq,
 137                                irq_hw_number_t hw)
 138 {
 139         int64_t err;
 140
 141         err = beat_construct_and_connect_irq_plug(virq, hw);
 142         if (err < 0)
 143                 return -EIO;
 144
 145         irq_set_status_flags(virq, IRQ_LEVEL);
 146         irq_set_chip_and_handler(virq, &beatic_pic, handle_fasteoi_irq);
 147         return 0;
 148 }
 149
 150 /*
 151  * Translate device-tree interrupt spec to irq_hw_number_t style (ulong),
 152  * to pass away to irq_create_mapping().
 153  *
 154  * Called from irq_create_of_mapping() only.
 155  * Note: We have only 1 entry to translate.
 156  */
 157 static int beatic_pic_host_xlate(struct irq_host *h, struct device_node *ct,
 158                                  const u32 *intspec, unsigned int intsize,
 159                                  irq_hw_number_t *out_hwirq,
 160                                  unsigned int *out_flags)
 161 {
 162         const u64 *intspec2 = (const u64 *)intspec;
 163
 164         *out_hwirq = *intspec2;
 165         *out_flags |= IRQ_TYPE_LEVEL_LOW;
 166         return 0;
 167 }
 168
 169 static int beatic_pic_host_match(struct irq_host *h, struct device_node *np)
 170 {
 171         /* Match all */
 172         return 1;
 173 }
 174
 175 static struct irq_host_ops beatic_pic_host_ops = {
 176         .map = beatic_pic_host_map,
 177         .unmap = beatic_pic_host_unmap,
 178         .xlate = beatic_pic_host_xlate,
 179         .match = beatic_pic_host_match,
 180 };
 181
 182 /*
 183  * Get an IRQ number
 184  * Note: returns VIRQ
 185  */
 186 static inline unsigned int beatic_get_irq_plug(void)
 187 {
 188         int i;
 189         uint64_t        pending[4], ub;
 190
 191         for (i = 0; i < MAX_IRQS; i += 256) {
 192                 beat_detect_pending_interrupts(i, pending);
 193                 __asm__ ("cntlzd %0,%1":"=r"(ub):
 194                         "r"(pending[0] & beatic_irq_mask_enable[i/64+0]
 195                                        & beatic_irq_mask_ack[i/64+0]));
 196                 if (ub != 64)
 197                         return i + ub + 0;
 198                 __asm__ ("cntlzd %0,%1":"=r"(ub):
 199                         "r"(pending[1] & beatic_irq_mask_enable[i/64+1]
 200                                        & beatic_irq_mask_ack[i/64+1]));
 201                 if (ub != 64)
 202                         return i + ub + 64;
 203                 __asm__ ("cntlzd %0,%1":"=r"(ub):
 204                         "r"(pending[2] & beatic_irq_mask_enable[i/64+2]
 205                                        & beatic_irq_mask_ack[i/64+2]));
 206                 if (ub != 64)
 207                         return i + ub + 128;
 208                 __asm__ ("cntlzd %0,%1":"=r"(ub):
 209                         "r"(pending[3] & beatic_irq_mask_enable[i/64+3]
 210                                        & beatic_irq_mask_ack[i/64+3]));
 211                 if (ub != 64)
 212                         return i + ub + 192;
 213         }
 214
 215         return NO_IRQ;
 216 }
 217 unsigned int beatic_get_irq(void)
 218 {
 219         unsigned int ret;
 220
 221         ret = beatic_get_irq_plug();
 222         if (ret != NO_IRQ)
 223                 beatic_ack_irq(irq_get_irq_data(ret));
 224         return ret;
 225 }
 226
 227 /*
 228  */
 229 void __init beatic_init_IRQ(void)
 230 {
 231         int     i;
 232
 233         memset(beatic_irq_mask_enable, 0, sizeof(beatic_irq_mask_enable));
 234         memset(beatic_irq_mask_ack, 255, sizeof(beatic_irq_mask_ack));
 235         for (i = 0; i < MAX_IRQS; i += 256)
 236                 beat_set_interrupt_mask(i, 0L, 0L, 0L, 0L);
 237
 238         /* Set out get_irq function */
 239         ppc_md.get_irq = beatic_get_irq;
 240
 241         /* Allocate an irq host */
 242         beatic_host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0,
 243                                      &beatic_pic_host_ops,
 244                                          0);
 245         BUG_ON(beatic_host == NULL);
 246         irq_set_default_host(beatic_host);
 247 }
 248
 249 void beatic_deinit_IRQ(void)
 250 {
 251         int     i;
 252
 253         for (i = 1; i < NR_IRQS; i++)
 254                 beat_destruct_irq_plug(i);
 255 }