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/config.h>
  18 #include <linux/errno.h>
  19 #include <linux/init.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/ioport.h>
  22 #include <linux/module.h>
  23 #include <linux/slab.h>
  24 #include <linux/types.h>
  25
  26 #include <asm/hardware.h>
  27 #include <asm/io.h>
  28
  29 #include "gsc.h"
  30
  31 #undef DEBUG
  32
  33 #ifdef DEBUG
  34 #define DEBPRINTK printk
  35 #else
  36 #define DEBPRINTK(x,...)
  37 #endif
  38
  39 int gsc_alloc_irq(struct gsc_irq *i)
  40 {
  41         int irq = txn_alloc_irq(GSC_EIM_WIDTH);
  42         if (irq < 0) {
  43                 printk("cannot get irq\n");
  44                 return irq;
  45         }
  46
  47         i->txn_addr = txn_alloc_addr(irq);
  48         i->txn_data = txn_alloc_data(irq);
  49         i->irq = irq;
  50
  51         return irq;
  52 }
  53
  54 int gsc_claim_irq(struct gsc_irq *i, int irq)
  55 {
  56         int c = irq;
  57
  58         irq += CPU_IRQ_BASE; /* virtualize the IRQ first */
  59
  60         irq = txn_claim_irq(irq);
  61         if (irq < 0) {
  62                 printk("cannot claim irq %d\n", c);
  63                 return irq;
  64         }
  65
  66         i->txn_addr = txn_alloc_addr(irq);
  67         i->txn_data = txn_alloc_data(irq);
  68         i->irq = irq;
  69
  70         return irq;
  71 }
  72
  73 EXPORT_SYMBOL(gsc_alloc_irq);
  74 EXPORT_SYMBOL(gsc_claim_irq);
  75
  76 /* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
  77 irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev, struct pt_regs *regs)
  78 {
  79         unsigned long irr;
  80         struct gsc_asic *gsc_asic = dev;
  81
  82         irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR);
  83         if (irr == 0)
  84                 return IRQ_NONE;
  85
  86         DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr);
  87
  88         do {
  89                 int local_irq = __ffs(irr);
  90                 unsigned int irq = gsc_asic->global_irq[local_irq];
  91                 __do_IRQ(irq, regs);
  92                 irr &= ~(1 << local_irq);
  93         } while (irr);
  94
  95         return IRQ_HANDLED;
  96 }
  97
  98 int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
  99 {
 100         int local_irq;
 101
 102         for (local_irq = 0; local_irq < limit; local_irq++) {
 103                 if (global_irqs[local_irq] == irq)
 104                         return local_irq;
 105         }
 106
 107         return NO_IRQ;
 108 }
 109
 110 static void gsc_asic_disable_irq(unsigned int irq)
 111 {
 112         struct gsc_asic *irq_dev = irq_desc[irq].handler_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", __FUNCTION__, 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 gsc_asic *irq_dev = irq_desc[irq].handler_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", __FUNCTION__, 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 hw_interrupt_type gsc_asic_interrupt_type = {
 151         .typename =     "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 hw_interrupt_type *type, void *data)
 161 {
 162         static int irq = GSC_IRQ_BASE;
 163
 164         if (irq > GSC_IRQ_MAX)
 165                 return NO_IRQ;
 166
 167         irq_desc[irq].handler = type;
 168         irq_desc[irq].handler_data = data;
 169         return irq++;
 170 }
 171
 172 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
 173 {
 174         int irq = asic->global_irq[local_irq];
 175
 176         if (irq <= 0) {
 177                 irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
 178                 if (irq == NO_IRQ)
 179                         return;
 180
 181                 asic->global_irq[local_irq] = irq;
 182         }
 183         *irqp = irq;
 184 }
 185
 186 static struct device *next_device(struct klist_iter *i)
 187 {
 188         struct klist_node * n = klist_next(i);
 189         return n ? container_of(n, struct device, knode_parent) : NULL;
 190 }
 191
 192 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
 193                         void (*choose_irq)(struct parisc_device *, void *))
 194 {
 195         struct device *dev;
 196         struct klist_iter i;
 197
 198         klist_iter_init(&parent->dev.klist_children, &i);
 199         while ((dev = next_device(&i))) {
 200                 struct parisc_device *padev = to_parisc_device(dev);
 201
 202                 /* work-around for 715/64 and others which have parent
 203                    at path [5] and children at path [5/0/x] */
 204                 if (padev->id.hw_type == HPHW_FAULTY)
 205                         return gsc_fixup_irqs(padev, ctrl, choose_irq);
 206                 choose_irq(padev, ctrl);
 207         }
 208         klist_iter_exit(&i);
 209 }
 210
 211 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
 212 {
 213         struct resource *res;
 214         int i;
 215
 216         gsc_asic->gsc = parent;
 217
 218         /* Initialise local irq -> global irq mapping */
 219         for (i = 0; i < 32; i++) {
 220                 gsc_asic->global_irq[i] = NO_IRQ;
 221         }
 222
 223         /* allocate resource region */
 224         res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
 225         if (res) {
 226                 res->flags = IORESOURCE_MEM;    /* do not mark it busy ! */
 227         }
 228
 229 #if 0
 230         printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
 231                         parent->irq, gsc_asic->eim);
 232         if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
 233                 printk("  IMR is non-zero! (0x%x)",
 234                                 gsc_readl(gsc_asic->hpa + OFFSET_IMR));
 235         printk("\n");
 236 #endif
 237
 238         return 0;
 239 }
 240
 241 extern struct parisc_driver lasi_driver;
 242 extern struct parisc_driver asp_driver;
 243 extern struct parisc_driver wax_driver;
 244
 245 void __init gsc_init(void)
 246 {
 247 #ifdef CONFIG_GSC_LASI
 248         register_parisc_driver(&lasi_driver);
 249         register_parisc_driver(&asp_driver);
 250 #endif
 251 #ifdef CONFIG_GSC_WAX
 252         register_parisc_driver(&wax_driver);
 253 #endif
 254 }