linux/arch/powerpc/platforms/cell/beat_interrupt.c
<<
>>
Prefs
   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
  33static DEFINE_RAW_SPINLOCK(beatic_irq_mask_lock);
  34static uint64_t beatic_irq_mask_enable[(MAX_IRQS+255)/64];
  35static uint64_t beatic_irq_mask_ack[(MAX_IRQS+255)/64];
  36
  37static 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 */
  45static 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
  64static 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
  74static 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
  84static 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
  94static 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
 112static 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 */
 125static 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 */
 136static 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 */
 157static 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
 169static int beatic_pic_host_match(struct irq_host *h, struct device_node *np)
 170{
 171        /* Match all */
 172        return 1;
 173}
 174
 175static 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 */
 186static 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}
 217unsigned 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 */
 229void __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
 249void beatic_deinit_IRQ(void)
 250{
 251        int     i;
 252
 253        for (i = 1; i < NR_IRQS; i++)
 254                beat_destruct_irq_plug(i);
 255}
 256