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/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
  38 int 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
  53 int 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
  72 EXPORT_SYMBOL(gsc_alloc_irq);
  73 EXPORT_SYMBOL(gsc_claim_irq);
  74
  75 /* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
  76 irqreturn_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
  97 int 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
 109 static 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
 125 static 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
 145 static unsigned int gsc_asic_startup_irq(unsigned int irq)
 146 {
 147         gsc_asic_enable_irq(irq);
 148         return 0;
 149 }
 150
 151 static 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
 161 int 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
 175 void 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
 189 static 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
 195 void 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
 214 int 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
 244 extern struct parisc_driver lasi_driver;
 245 extern struct parisc_driver asp_driver;
 246 extern struct parisc_driver wax_driver;
 247
 248 void __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 }