LXR linux/arch/powerpc/sysdev/mpic

   1/*
   2 * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License
   6 * as published by the Free Software Foundation; version 2 of the
   7 * License.
   8 *
   9 */
  10
  11#include <linux/irq.h>
  12#include <linux/bitmap.h>
  13#include <linux/msi.h>
  14#include <asm/mpic.h>
  15#include <asm/prom.h>
  16#include <asm/hw_irq.h>
  17#include <asm/ppc-pci.h>
  18#include <asm/msi_bitmap.h>
  19
  20#include <sysdev/mpic.h>
  21
  22void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
  23{
  24        /* The mpic calls this even when there is no allocator setup */
  25        if (!mpic->msi_bitmap.bitmap)
  26                return;
  27
  28        msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
  29}
  30
  31#ifdef CONFIG_MPIC_U3_HT_IRQS
  32static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
  33{
  34        irq_hw_number_t hwirq;
  35        struct irq_host_ops *ops = mpic->irqhost->ops;
  36        struct device_node *np;
  37        int flags, index, i;
  38        struct of_irq oirq;
  39
  40        pr_debug("mpic: found U3, guessing msi allocator setup\n");
  41
  42        /* Reserve source numbers we know are reserved in the HW */
  43        for (i = 0;   i < 8;   i++)
  44                msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
  45
  46        for (i = 42;  i < 46;  i++)
  47                msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
  48
  49        for (i = 100; i < 105; i++)
  50                msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, i);
  51
  52        np = NULL;
  53        while ((np = of_find_all_nodes(np))) {
  54                pr_debug("mpic: mapping hwirqs for %s\n", np->full_name);
  55
  56                index = 0;
  57                while (of_irq_map_one(np, index++, &oirq) == 0) {
  58                        ops->xlate(mpic->irqhost, NULL, oirq.specifier,
  59                                                oirq.size, &hwirq, &flags);
  60                        msi_bitmap_reserve_hwirq(&mpic->msi_bitmap, hwirq);
  61                }
  62        }
  63
  64        return 0;
  65}
  66#else
  67static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
  68{
  69        return -1;
  70}
  71#endif
  72
  73int mpic_msi_init_allocator(struct mpic *mpic)
  74{
  75        int rc;
  76
  77        rc = msi_bitmap_alloc(&mpic->msi_bitmap, mpic->irq_count,
  78                              mpic->irqhost->of_node);
  79        if (rc)
  80                return rc;
  81
  82        rc = msi_bitmap_reserve_dt_hwirqs(&mpic->msi_bitmap);
  83        if (rc > 0) {
  84                if (mpic->flags & MPIC_U3_HT_IRQS)
  85                        rc = mpic_msi_reserve_u3_hwirqs(mpic);
  86
  87                if (rc) {
  88                        msi_bitmap_free(&mpic->msi_bitmap);
  89                        return rc;
  90                }
  91        }
  92
  93        return 0;
  94}
  95