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   1 #include <linux/dmar.h>
   2 #include <asm/io_apic.h>
   3 #include "intel-iommu.h"
   4 #include "intr_remapping.h"
   5
   6 static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
   7 static int ir_ioapic_num;
   8
   9 static int ir_parse_ioapic_scope(struct acpi_dmar_header *header,
  10                                  struct intel_iommu *iommu)
  11 {
  12         struct acpi_dmar_hardware_unit *drhd;
  13         struct acpi_dmar_device_scope *scope;
  14         void *start, *end;
  15
  16         drhd = (struct acpi_dmar_hardware_unit *)header;
  17
  18         start = (void *)(drhd + 1);
  19         end = ((void *)drhd) + header->length;
  20
  21         while (start < end) {
  22                 scope = start;
  23                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
  24                         if (ir_ioapic_num == MAX_IO_APICS) {
  25                                 printk(KERN_WARNING "Exceeded Max IO APICS\n");
  26                                 return -1;
  27                         }
  28
  29                         printk(KERN_INFO "IOAPIC id %d under DRHD base"
  30                                " 0x%Lx\n", scope->enumeration_id,
  31                                drhd->address);
  32
  33                         ir_ioapic[ir_ioapic_num].iommu = iommu;
  34                         ir_ioapic[ir_ioapic_num].id = scope->enumeration_id;
  35                         ir_ioapic_num++;
  36                 }
  37                 start += scope->length;
  38         }
  39
  40         return 0;
  41 }
  42
  43 /*
  44  * Finds the assocaition between IOAPIC's and its Interrupt-remapping
  45  * hardware unit.
  46  */
  47 int __init parse_ioapics_under_ir(void)
  48 {
  49         struct dmar_drhd_unit *drhd;
  50         int ir_supported = 0;
  51
  52         for_each_drhd_unit(drhd) {
  53                 struct intel_iommu *iommu = drhd->iommu;
  54
  55                 if (ecap_ir_support(iommu->ecap)) {
  56                         if (ir_parse_ioapic_scope(drhd->hdr, iommu))
  57                                 return -1;
  58
  59                         ir_supported = 1;
  60                 }
  61         }
  62
  63         if (ir_supported && ir_ioapic_num != nr_ioapics) {
  64                 printk(KERN_WARNING
  65                        "Not all IO-APIC's listed under remapping hardware\n");
  66                 return -1;
  67         }
  68
  69         return ir_supported;
  70 }