drivers/parisc/gsc.c

   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/types.h>
  23
  24 #include <asm/hardware.h>
  25 #include <asm/io.h>
  26
  27 #include "gsc.h"
  28
  29 #undef DEBUG
  30
  31 #ifdef DEBUG
  32 #define DEBPRINTK printk
  33 #else
  34 #define DEBPRINTK(x,...)
  35 #endif
  36
  37 int gsc_alloc_irq(struct gsc_irq *i)
  38 {
  39         int irq = txn_alloc_irq(GSC_EIM_WIDTH);
  40         if (irq < 0) {
  41                 printk("cannot get irq\n");
  42                 return irq;
  43         }
  44
  45         i->txn_addr = txn_alloc_addr(irq);
  46         i->txn_data = txn_alloc_data(irq);
  47         i->irq = irq;
  48
  49         return irq;
  50 }
  51
  52 int gsc_claim_irq(struct gsc_irq *i, int irq)
  53 {
  54         int c = irq;
  55
  56         irq += CPU_IRQ_BASE; /* virtualize the IRQ first */
  57
  58         irq = txn_claim_irq(irq);
  59         if (irq < 0) {
  60                 printk("cannot claim irq %d\n", c);
  61                 return irq;
  62         }
  63
  64         i->txn_addr = txn_alloc_addr(irq);
  65         i->txn_data = txn_alloc_data(irq);
  66         i->irq = irq;
  67
  68         return irq;
  69 }
  70
  71 EXPORT_SYMBOL(gsc_alloc_irq);
  72 EXPORT_SYMBOL(gsc_claim_irq);
  73
  74 /* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
  75 irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev)
  76 {
  77         unsigned long irr;
  78         struct gsc_asic *gsc_asic = dev;
  79
  80         irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR);
  81         if (irr == 0)
  82                 return IRQ_NONE;
  83
  84         DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr);
  85
  86         do {
  87                 int local_irq = __ffs(irr);
  88                 unsigned int irq = gsc_asic->global_irq[local_irq];
  89                 __do_IRQ(irq);
  90                 irr &= ~(1 << local_irq);
  91         } while (irr);
  92
  93         return IRQ_HANDLED;
  94 }
  95
  96 int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
  97 {
  98         int local_irq;
  99
 100         for (local_irq = 0; local_irq < limit; local_irq++) {
 101                 if (global_irqs[local_irq] == irq)
 102                         return local_irq;
 103         }
 104
 105         return NO_IRQ;
 106 }
 107
 108 static void gsc_asic_disable_irq(unsigned int irq)
 109 {
 110         struct irq_desc *desc = irq_to_desc(irq);
 111         struct gsc_asic *irq_dev = desc->chip_data;
 112         int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 113         u32 imr;
 114
 115         DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
 116                         irq_dev->name, imr);
 117
 118         /* Disable the IRQ line by clearing the bit in the IMR */
 119         imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
 120         imr &= ~(1 << local_irq);
 121         gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
 122 }
 123
 124 static void gsc_asic_enable_irq(unsigned int irq)
 125 {
 126         struct irq_desc *desc = irq_to_desc(irq);
 127         struct gsc_asic *irq_dev = desc->chip_data;
 128         int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 129         u32 imr;
 130
 131         DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
 132                         irq_dev->name, imr);
 133
 134         /* Enable the IRQ line by setting the bit in the IMR */
 135         imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
 136         imr |= 1 << local_irq;
 137         gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
 138         /*
 139          * FIXME: read IPR to make sure the IRQ isn't already pending.
 140          *   If so, we need to read IRR and manually call do_irq().
 141          */
 142 }
 143
 144 static unsigned int gsc_asic_startup_irq(unsigned int irq)
 145 {
 146         gsc_asic_enable_irq(irq);
 147         return 0;
 148 }
 149
 150 static struct irq_chip gsc_asic_interrupt_type = {
 151         .name    =      "GSC-ASIC",
 152         .startup =      gsc_asic_startup_irq,
 153         .shutdown =     gsc_asic_disable_irq,
 154         .enable =       gsc_asic_enable_irq,
 155         .disable =      gsc_asic_disable_irq,
 156         .ack =          no_ack_irq,
 157         .end =          no_end_irq,
 158 };
 159
 160 int gsc_assign_irq(struct irq_chip *type, void *data)
 161 {
 162         static int irq = GSC_IRQ_BASE;
 163         struct irq_desc *desc;
 164
 165         if (irq > GSC_IRQ_MAX)
 166                 return NO_IRQ;
 167
 168         desc = irq_to_desc(irq);
 169         desc->chip = type;
 170         desc->chip_data = data;
 171         return irq++;
 172 }
 173
 174 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
 175 {
 176         int irq = asic->global_irq[local_irq];
 177
 178         if (irq <= 0) {
 179                 irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
 180                 if (irq == NO_IRQ)
 181                         return;
 182
 183                 asic->global_irq[local_irq] = irq;
 184         }
 185         *irqp = irq;
 186 }
 187
 188 struct gsc_fixup_struct {
 189         void (*choose_irq)(struct parisc_device *, void *);
 190         void *ctrl;
 191 };
 192
 193 static int gsc_fixup_irqs_callback(struct device *dev, void *data)
 194 {
 195         struct parisc_device *padev = to_parisc_device(dev);
 196         struct gsc_fixup_struct *gf = data;
 197
 198         /* work-around for 715/64 and others which have parent
 199            at path [5] and children at path [5/0/x] */
 200         if (padev->id.hw_type == HPHW_FAULTY)
 201                 gsc_fixup_irqs(padev, gf->ctrl, gf->choose_irq);
 202         gf->choose_irq(padev, gf->ctrl);
 203
 204         return 0;
 205 }
 206
 207 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
 208                         void (*choose_irq)(struct parisc_device *, void *))
 209 {
 210         struct gsc_fixup_struct data = {
 211                 .choose_irq     = choose_irq,
 212                 .ctrl           = ctrl,
 213         };
 214
 215         device_for_each_child(&parent->dev, &data, gsc_fixup_irqs_callback);
 216 }
 217
 218 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
 219 {
 220         struct resource *res;
 221         int i;
 222
 223         gsc_asic->gsc = parent;
 224
 225         /* Initialise local irq -> global irq mapping */
 226         for (i = 0; i < 32; i++) {
 227                 gsc_asic->global_irq[i] = NO_IRQ;
 228         }
 229
 230         /* allocate resource region */
 231         res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
 232         if (res) {
 233                 res->flags = IORESOURCE_MEM;    /* do not mark it busy ! */
 234         }
 235
 236 #if 0
 237         printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
 238                         parent->irq, gsc_asic->eim);
 239         if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
 240                 printk("  IMR is non-zero! (0x%x)",
 241                                 gsc_readl(gsc_asic->hpa + OFFSET_IMR));
 242         printk("\n");
 243 #endif
 244
 245         return 0;
 246 }
 247
 248 extern struct parisc_driver lasi_driver;
 249 extern struct parisc_driver asp_driver;
 250 extern struct parisc_driver wax_driver;
 251
 252 void __init gsc_init(void)
 253 {
 254 #ifdef CONFIG_GSC_LASI
 255         register_parisc_driver(&lasi_driver);
 256         register_parisc_driver(&asp_driver);
 257 #endif
 258 #ifdef CONFIG_GSC_WAX
 259         register_parisc_driver(&wax_driver);
 260 #endif
 261 }