x2APIC/VT-d: improve interrupt remapping and queued invalidation enabling and disabling

x2APIC depends on interrupt remapping, so interrupt remapping needs to
be enabled before x2APIC. Usually x2APIC is not enabled
(x2apic_enabled=0) when enable interrupt remapping, although x2APIC
will be enabled later. So it needs to pass a parameter to set
interrupt mode in intremap_enable, instead of checking
x2apic_enable. This patch adds a parameter "eim" to intremap_enable to
achieve it.  Interrupt remapping and queued invalidation are already
enabled when enable x2apic, so it needn't to enable them again when
setup iommu. This patch checks if interrupt remapping and queued
invalidation are already enable or not, and won't enable them if
already enabled. It does the similar in disabling, that's to say don't
disable them if already disabled.

Signed-off-by: Weidong Han <weidong.han@intel.com>

diff --git a/xen/drivers/passthrough/vtd/extern.h b/xen/drivers/passthrough/vtd/extern.h
index 2e923922d67e450f78e5030bb15f0d85a2472922..131e97b4359b34f9e0eb5e15565c95d851682ede 100644 (file)
--- a/xen/drivers/passthrough/vtd/extern.h
+++ b/xen/drivers/passthrough/vtd/extern.h
@@ -33,7 +33,7 @@ extern struct keyhandler dump_iommu_info_keyhandler;
 
 int enable_qinval(struct iommu *iommu);
 void disable_qinval(struct iommu *iommu);
-int enable_intremap(struct iommu *iommu);
+int enable_intremap(struct iommu *iommu, int eim);
 void disable_intremap(struct iommu *iommu);
 int queue_invalidate_context(struct iommu *iommu,
     u16 did, u16 source_id, u8 function_mask, u8 granu);

diff --git a/xen/drivers/passthrough/vtd/intremap.c b/xen/drivers/passthrough/vtd/intremap.c
index 215428ffd8616602f5be2e1c5da47444b6660f6d..6552e5297fd70545d0f136e0f5f2767bba82ff0a 100644 (file)
--- a/xen/drivers/passthrough/vtd/intremap.c
+++ b/xen/drivers/passthrough/vtd/intremap.c
@@ -711,7 +711,7 @@ void msi_msg_write_remap_rte(
 }
 #endif
 
-int enable_intremap(struct iommu *iommu)
+int enable_intremap(struct iommu *iommu, int eim)
 {
     struct acpi_drhd_unit *drhd;
     struct ir_ctrl *ir_ctrl;
@@ -721,10 +721,25 @@ int enable_intremap(struct iommu *iommu)
     ASSERT(ecap_intr_remap(iommu->ecap) && iommu_intremap);
 
     ir_ctrl = iommu_ir_ctrl(iommu);
+    sts = dmar_readl(iommu->reg, DMAR_GSTS_REG);
+
+    /* Return if already enabled by Xen */
+    if ( (sts & DMA_GSTS_IRES) && ir_ctrl->iremap_maddr )
+        return 0;
+
+    sts = dmar_readl(iommu->reg, DMAR_GSTS_REG);
+    if ( !(sts & DMA_GSTS_QIES) )
+    {
+        dprintk(XENLOG_ERR VTDPREFIX,
+                "Queued invalidation is not enabled, should not enable "
+                "interrupt remapping\n");
+        return -EINVAL;
+    }
+
     if ( ir_ctrl->iremap_maddr == 0 )
     {
         drhd = iommu_to_drhd(iommu);
-        ir_ctrl->iremap_maddr = alloc_pgtable_maddr(drhd, IREMAP_ARCH_PAGE_NR );
+        ir_ctrl->iremap_maddr = alloc_pgtable_maddr(drhd, IREMAP_ARCH_PAGE_NR);
         if ( ir_ctrl->iremap_maddr == 0 )
         {
             dprintk(XENLOG_WARNING VTDPREFIX,
@@ -737,7 +752,7 @@ int enable_intremap(struct iommu *iommu)
 #ifdef CONFIG_X86
     /* set extended interrupt mode bit */
     ir_ctrl->iremap_maddr |=
-            x2apic_enabled ? (1 << IRTA_REG_EIME_SHIFT) : 0;
+            eim ? (1 << IRTA_REG_EIME_SHIFT) : 0;
 #endif
     spin_lock_irqsave(&iommu->register_lock, flags);
 
@@ -774,13 +789,18 @@ void disable_intremap(struct iommu *iommu)
     u32 sts;
     unsigned long flags;
 
-    ASSERT(ecap_intr_remap(iommu->ecap) && iommu_intremap);
+    if ( !ecap_intr_remap(iommu->ecap) )
+        return;
 
     spin_lock_irqsave(&iommu->register_lock, flags);
     sts = dmar_readl(iommu->reg, DMAR_GSTS_REG);
+    if ( !(sts & DMA_GSTS_IRES) )
+        goto out;
+
     dmar_writel(iommu->reg, DMAR_GCMD_REG, sts & (~DMA_GCMD_IRE));
 
     IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, dmar_readl,
                   !(sts & DMA_GSTS_IRES), sts);
+out:
     spin_unlock_irqrestore(&iommu->register_lock, flags);
 }

diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index c867d7fdcefda2154207849a71565830da4ca3d0..c04d429939c85715bb03b0e7ffe4599928d22530 100644 (file)
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1834,24 +1834,20 @@ static int init_vtd_hw(void)
         spin_lock_irqsave(&iommu->register_lock, flags);
         dmar_writel(iommu->reg, DMAR_FECTL_REG, 0);
         spin_unlock_irqrestore(&iommu->register_lock, flags);
-
-        /* initialize flush functions */
-        flush = iommu_get_flush(iommu);
-        flush->context = flush_context_reg;
-        flush->iotlb = flush_iotlb_reg;
     }
 
-    if ( iommu_qinval )
+    for_each_drhd_unit ( drhd )
     {
-        for_each_drhd_unit ( drhd )
+        iommu = drhd->iommu;
+        /*
+         * If queued invalidation not enabled, use regiser based
+         * invalidation
+         */
+        if ( enable_qinval(iommu) != 0 )
         {
-            iommu = drhd->iommu;
-            if ( enable_qinval(iommu) != 0 )
-            {
-                dprintk(XENLOG_INFO VTDPREFIX,
-                        "Failed to enable Queued Invalidation!\n");
-                break;
-            }
+            flush = iommu_get_flush(iommu);
+            flush->context = flush_context_reg;
+            flush->iotlb = flush_iotlb_reg;
         }
     }
 
@@ -1877,9 +1873,9 @@ static int init_vtd_hw(void)
         for_each_drhd_unit ( drhd )
         {
             iommu = drhd->iommu;
-            if ( enable_intremap(iommu) != 0 )
+            if ( enable_intremap(iommu, 0) != 0 )
             {
-                dprintk(XENLOG_INFO VTDPREFIX,
+                dprintk(XENLOG_WARNING VTDPREFIX,
                         "Failed to enable Interrupt Remapping!\n");
                 break;
             }

diff --git a/xen/drivers/passthrough/vtd/qinval.c b/xen/drivers/passthrough/vtd/qinval.c
index 7dde42b302ccfacd53b0274489c1fb67773c4efc..a1ac3ee7ba97cd37125b84069f1eee9413911dc4 100644 (file)
--- a/xen/drivers/passthrough/vtd/qinval.c
+++ b/xen/drivers/passthrough/vtd/qinval.c
@@ -437,10 +437,16 @@ int enable_qinval(struct iommu *iommu)
     u32 sts;
     unsigned long flags;
 
+    if ( !ecap_queued_inval(iommu->ecap) || !iommu_qinval )
+        return -ENOENT;
+
     qi_ctrl = iommu_qi_ctrl(iommu);
     flush = iommu_get_flush(iommu);
 
-    ASSERT(ecap_queued_inval(iommu->ecap) && iommu_qinval);
+    /* Return if already enabled by Xen */
+    sts = dmar_readl(iommu->reg, DMAR_GSTS_REG);
+    if ( (sts & DMA_GSTS_QIES) && qi_ctrl->qinval_maddr )
+        return 0;
 
     if ( qi_ctrl->qinval_maddr == 0 )
     {
@@ -488,14 +494,19 @@ void disable_qinval(struct iommu *iommu)
     u32 sts;
     unsigned long flags;
 
-    ASSERT(ecap_queued_inval(iommu->ecap) && iommu_qinval);
+    if ( !ecap_queued_inval(iommu->ecap) )
+        return;
 
     spin_lock_irqsave(&iommu->register_lock, flags);
     sts = dmar_readl(iommu->reg, DMAR_GSTS_REG);
+    if ( !(sts & DMA_GSTS_QIES) )
+        goto out;
+
     dmar_writel(iommu->reg, DMAR_GCMD_REG, sts & (~DMA_GCMD_QIE));
 
     /* Make sure hardware complete it */
     IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, dmar_readl,
                   !(sts & DMA_GSTS_QIES), sts);
+out:
     spin_unlock_irqrestore(&iommu->register_lock, flags);
 }