SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/pci/intr_remapping.c

   1 #include <linux/dmar.h>
   2 #include <linux/spinlock.h>
   3 #include <linux/jiffies.h>
   4 #include <linux/pci.h>
   5 #include <asm/io_apic.h>
   6 #include "intel-iommu.h"
   7 #include "intr_remapping.h"
   8
   9 static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
  10 static int ir_ioapic_num;
  11 int intr_remapping_enabled;
  12
  13 static void iommu_set_intr_remapping(struct intel_iommu *iommu, int mode)
  14 {
  15         u64 addr;
  16         u32 cmd, sts;
  17         unsigned long flags;
  18
  19         addr = virt_to_phys((void *)iommu->ir_table->base);
  20
  21         spin_lock_irqsave(&iommu->register_lock, flags);
  22
  23         dmar_writeq(iommu->reg + DMAR_IRTA_REG,
  24                     (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
  25
  26         /* Set interrupt-remapping table pointer */
  27         cmd = iommu->gcmd | DMA_GCMD_SIRTP;
  28         writel(cmd, iommu->reg + DMAR_GCMD_REG);
  29
  30         IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
  31                       readl, (sts & DMA_GSTS_IRTPS), sts);
  32         spin_unlock_irqrestore(&iommu->register_lock, flags);
  33
  34         /*
  35          * global invalidation of interrupt entry cache before enabling
  36          * interrupt-remapping.
  37          */
  38         qi_global_iec(iommu);
  39
  40         spin_lock_irqsave(&iommu->register_lock, flags);
  41
  42         /* Enable interrupt-remapping */
  43         cmd = iommu->gcmd | DMA_GCMD_IRE;
  44         iommu->gcmd |= DMA_GCMD_IRE;
  45         writel(cmd, iommu->reg + DMAR_GCMD_REG);
  46
  47         IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
  48                       readl, (sts & DMA_GSTS_IRES), sts);
  49
  50         spin_unlock_irqrestore(&iommu->register_lock, flags);
  51 }
  52
  53
  54 static int setup_intr_remapping(struct intel_iommu *iommu, int mode)
  55 {
  56         struct ir_table *ir_table;
  57         struct page *pages;
  58
  59         ir_table = iommu->ir_table = kzalloc(sizeof(struct ir_table),
  60                                              GFP_KERNEL);
  61
  62         if (!iommu->ir_table)
  63                 return -ENOMEM;
  64
  65         pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, INTR_REMAP_PAGE_ORDER);
  66
  67         if (!pages) {
  68                 printk(KERN_ERR "failed to allocate pages of order %d\n",
  69                        INTR_REMAP_PAGE_ORDER);
  70                 kfree(iommu->ir_table);
  71                 return -ENOMEM;
  72         }
  73
  74         ir_table->base = page_address(pages);
  75
  76         iommu_set_intr_remapping(iommu, mode);
  77         return 0;
  78 }
  79
  80 int __init enable_intr_remapping(int eim)
  81 {
  82         struct dmar_drhd_unit *drhd;
  83         int setup = 0;
  84
  85         /*
  86          * check for the Interrupt-remapping support
  87          */
  88         for_each_drhd_unit(drhd) {
  89                 struct intel_iommu *iommu = drhd->iommu;
  90
  91                 if (!ecap_ir_support(iommu->ecap))
  92                         continue;
  93
  94                 if (eim && !ecap_eim_support(iommu->ecap)) {
  95                         printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, "
  96                                " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap);
  97                         return -1;
  98                 }
  99         }
 100
 101         /*
 102          * Enable queued invalidation for all the DRHD's.
 103          */
 104         for_each_drhd_unit(drhd) {
 105                 int ret;
 106                 struct intel_iommu *iommu = drhd->iommu;
 107                 ret = dmar_enable_qi(iommu);
 108
 109                 if (ret) {
 110                         printk(KERN_ERR "DRHD %Lx: failed to enable queued, "
 111                                " invalidation, ecap %Lx, ret %d\n",
 112                                drhd->reg_base_addr, iommu->ecap, ret);
 113                         return -1;
 114                 }
 115         }
 116
 117         /*
 118          * Setup Interrupt-remapping for all the DRHD's now.
 119          */
 120         for_each_drhd_unit(drhd) {
 121                 struct intel_iommu *iommu = drhd->iommu;
 122
 123                 if (!ecap_ir_support(iommu->ecap))
 124                         continue;
 125
 126                 if (setup_intr_remapping(iommu, eim))
 127                         goto error;
 128
 129                 setup = 1;
 130         }
 131
 132         if (!setup)
 133                 goto error;
 134
 135         intr_remapping_enabled = 1;
 136
 137         return 0;
 138
 139 error:
 140         /*
 141          * handle error condition gracefully here!
 142          */
 143         return -1;
 144 }
 145
 146 static int ir_parse_ioapic_scope(struct acpi_dmar_header *header,
 147                                  struct intel_iommu *iommu)
 148 {
 149         struct acpi_dmar_hardware_unit *drhd;
 150         struct acpi_dmar_device_scope *scope;
 151         void *start, *end;
 152
 153         drhd = (struct acpi_dmar_hardware_unit *)header;
 154
 155         start = (void *)(drhd + 1);
 156         end = ((void *)drhd) + header->length;
 157
 158         while (start < end) {
 159                 scope = start;
 160                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
 161                         if (ir_ioapic_num == MAX_IO_APICS) {
 162                                 printk(KERN_WARNING "Exceeded Max IO APICS\n");
 163                                 return -1;
 164                         }
 165
 166                         printk(KERN_INFO "IOAPIC id %d under DRHD base"
 167                                " 0x%Lx\n", scope->enumeration_id,
 168                                drhd->address);
 169
 170                         ir_ioapic[ir_ioapic_num].iommu = iommu;
 171                         ir_ioapic[ir_ioapic_num].id = scope->enumeration_id;
 172                         ir_ioapic_num++;
 173                 }
 174                 start += scope->length;
 175         }
 176
 177         return 0;
 178 }
 179
 180 /*
 181  * Finds the assocaition between IOAPIC's and its Interrupt-remapping
 182  * hardware unit.
 183  */
 184 int __init parse_ioapics_under_ir(void)
 185 {
 186         struct dmar_drhd_unit *drhd;
 187         int ir_supported = 0;
 188
 189         for_each_drhd_unit(drhd) {
 190                 struct intel_iommu *iommu = drhd->iommu;
 191
 192                 if (ecap_ir_support(iommu->ecap)) {
 193                         if (ir_parse_ioapic_scope(drhd->hdr, iommu))
 194                                 return -1;
 195
 196                         ir_supported = 1;
 197                 }
 198         }
 199
 200         if (ir_supported && ir_ioapic_num != nr_ioapics) {
 201                 printk(KERN_WARNING
 202                        "Not all IO-APIC's listed under remapping hardware\n");
 203                 return -1;
 204         }
 205
 206         return ir_supported;
 207 }