linux/drivers/parisc/gsc.c
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   1/*
   2 * Interrupt management for most GSC and related devices.
   3 *
   4 * (c) Copyright 1999 Alex deVries for The Puffin Group
   5 * (c) Copyright 1999 Grant Grundler for Hewlett-Packard
   6 * (c) Copyright 1999 Matthew Wilcox
   7 * (c) Copyright 2000 Helge Deller
   8 * (c) Copyright 2001 Matthew Wilcox for Hewlett-Packard
   9 *
  10 *      This program is free software; you can redistribute it and/or modify
  11 *      it under the terms of the GNU General Public License as published by
  12 *      the Free Software Foundation; either version 2 of the License, or
  13 *      (at your option) any later version.
  14 */
  15
  16#include <linux/bitops.h>
  17#include <linux/errno.h>
  18#include <linux/init.h>
  19#include <linux/interrupt.h>
  20#include <linux/ioport.h>
  21#include <linux/module.h>
  22#include <linux/slab.h>
  23#include <linux/types.h>
  24
  25#include <asm/hardware.h>
  26#include <asm/io.h>
  27
  28#include "gsc.h"
  29
  30#undef DEBUG
  31
  32#ifdef DEBUG
  33#define DEBPRINTK printk
  34#else
  35#define DEBPRINTK(x,...)
  36#endif
  37
  38int gsc_alloc_irq(struct gsc_irq *i)
  39{
  40        int irq = txn_alloc_irq(GSC_EIM_WIDTH);
  41        if (irq < 0) {
  42                printk("cannot get irq\n");
  43                return irq;
  44        }
  45
  46        i->txn_addr = txn_alloc_addr(irq);
  47        i->txn_data = txn_alloc_data(irq);
  48        i->irq = irq;
  49
  50        return irq;
  51}
  52
  53int gsc_claim_irq(struct gsc_irq *i, int irq)
  54{
  55        int c = irq;
  56
  57        irq += CPU_IRQ_BASE; /* virtualize the IRQ first */
  58
  59        irq = txn_claim_irq(irq);
  60        if (irq < 0) {
  61                printk("cannot claim irq %d\n", c);
  62                return irq;
  63        }
  64
  65        i->txn_addr = txn_alloc_addr(irq);
  66        i->txn_data = txn_alloc_data(irq);
  67        i->irq = irq;
  68
  69        return irq;
  70}
  71
  72EXPORT_SYMBOL(gsc_alloc_irq);
  73EXPORT_SYMBOL(gsc_claim_irq);
  74
  75/* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
  76irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev)
  77{
  78        unsigned long irr;
  79        struct gsc_asic *gsc_asic = dev;
  80
  81        irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR);
  82        if (irr == 0)
  83                return IRQ_NONE;
  84
  85        DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr);
  86
  87        do {
  88                int local_irq = __ffs(irr);
  89                unsigned int irq = gsc_asic->global_irq[local_irq];
  90                __do_IRQ(irq);
  91                irr &= ~(1 << local_irq);
  92        } while (irr);
  93
  94        return IRQ_HANDLED;
  95}
  96
  97int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
  98{
  99        int local_irq;
 100
 101        for (local_irq = 0; local_irq < limit; local_irq++) {
 102                if (global_irqs[local_irq] == irq)
 103                        return local_irq;
 104        }
 105
 106        return NO_IRQ;
 107}
 108
 109static void gsc_asic_disable_irq(unsigned int irq)
 110{
 111        struct irq_desc *desc = irq_to_desc(irq);
 112        struct gsc_asic *irq_dev = desc->chip_data;
 113        int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 114        u32 imr;
 115
 116        DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
 117                        irq_dev->name, imr);
 118
 119        /* Disable the IRQ line by clearing the bit in the IMR */
 120        imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
 121        imr &= ~(1 << local_irq);
 122        gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
 123}
 124
 125static void gsc_asic_enable_irq(unsigned int irq)
 126{
 127        struct irq_desc *desc = irq_to_desc(irq);
 128        struct gsc_asic *irq_dev = desc->chip_data;
 129        int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 130        u32 imr;
 131
 132        DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
 133                        irq_dev->name, imr);
 134
 135        /* Enable the IRQ line by setting the bit in the IMR */
 136        imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
 137        imr |= 1 << local_irq;
 138        gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
 139        /*
 140         * FIXME: read IPR to make sure the IRQ isn't already pending.
 141         *   If so, we need to read IRR and manually call do_irq().
 142         */
 143}
 144
 145static unsigned int gsc_asic_startup_irq(unsigned int irq)
 146{
 147        gsc_asic_enable_irq(irq);
 148        return 0;
 149}
 150
 151static struct hw_interrupt_type gsc_asic_interrupt_type = {
 152        .typename =     "GSC-ASIC",
 153        .startup =      gsc_asic_startup_irq,
 154        .shutdown =     gsc_asic_disable_irq,
 155        .enable =       gsc_asic_enable_irq,
 156        .disable =      gsc_asic_disable_irq,
 157        .ack =          no_ack_irq,
 158        .end =          no_end_irq,
 159};
 160
 161int gsc_assign_irq(struct hw_interrupt_type *type, void *data)
 162{
 163        static int irq = GSC_IRQ_BASE;
 164        struct irq_desc *desc;
 165
 166        if (irq > GSC_IRQ_MAX)
 167                return NO_IRQ;
 168
 169        desc = irq_to_desc(irq);
 170        desc->chip = type;
 171        desc->chip_data = data;
 172        return irq++;
 173}
 174
 175void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
 176{
 177        int irq = asic->global_irq[local_irq];
 178        
 179        if (irq <= 0) {
 180                irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
 181                if (irq == NO_IRQ)
 182                        return;
 183
 184                asic->global_irq[local_irq] = irq;
 185        }
 186        *irqp = irq;
 187}
 188
 189static struct device *next_device(struct klist_iter *i)
 190{
 191        struct klist_node * n = klist_next(i);
 192        return n ? container_of(n, struct device, knode_parent) : NULL;
 193}
 194
 195void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
 196                        void (*choose_irq)(struct parisc_device *, void *))
 197{
 198        struct device *dev;
 199        struct klist_iter i;
 200
 201        klist_iter_init(&parent->dev.klist_children, &i);
 202        while ((dev = next_device(&i))) {
 203                struct parisc_device *padev = to_parisc_device(dev);
 204
 205                /* work-around for 715/64 and others which have parent 
 206                   at path [5] and children at path [5/0/x] */
 207                if (padev->id.hw_type == HPHW_FAULTY)
 208                        return gsc_fixup_irqs(padev, ctrl, choose_irq);
 209                choose_irq(padev, ctrl);
 210        }
 211        klist_iter_exit(&i);
 212}
 213
 214int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
 215{
 216        struct resource *res;
 217        int i;
 218
 219        gsc_asic->gsc = parent;
 220
 221        /* Initialise local irq -> global irq mapping */
 222        for (i = 0; i < 32; i++) {
 223                gsc_asic->global_irq[i] = NO_IRQ;
 224        }
 225
 226        /* allocate resource region */
 227        res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
 228        if (res) {
 229                res->flags = IORESOURCE_MEM;    /* do not mark it busy ! */
 230        }
 231
 232#if 0
 233        printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
 234                        parent->irq, gsc_asic->eim);
 235        if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
 236                printk("  IMR is non-zero! (0x%x)",
 237                                gsc_readl(gsc_asic->hpa + OFFSET_IMR));
 238        printk("\n");
 239#endif
 240
 241        return 0;
 242}
 243
 244extern struct parisc_driver lasi_driver;
 245extern struct parisc_driver asp_driver;
 246extern struct parisc_driver wax_driver;
 247
 248void __init gsc_init(void)
 249{
 250#ifdef CONFIG_GSC_LASI
 251        register_parisc_driver(&lasi_driver);
 252        register_parisc_driver(&asp_driver);
 253#endif
 254#ifdef CONFIG_GSC_WAX
 255        register_parisc_driver(&wax_driver);
 256#endif
 257}
 258