[patch 04/13] dmar: routines for disabling queued invalidation and intr remapping

Suresh Siddha
2009-03-17T00:29:01Z

[-- Attachment #1: dmar_qi_routines.patch --]
[-- Type: text/plain, Size: 2907 bytes --]

Routines for disabling queued invalidation and interrupt remapping.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
---

Index: tip/drivers/pci/dmar.c
===================================================================
--- tip.orig/drivers/pci/dmar.c
+++ tip/drivers/pci/dmar.c
@@ -754,6 +754,42 @@ int qi_flush_iotlb(struct intel_iommu *i
}

/*
+ * Disable Queued Invalidation interface.
+ */
+void dmar_disable_qi(struct intel_iommu *iommu)
+{
+ unsigned long flags;
+ u32 sts;
+ cycles_t start_time = get_cycles();
+
+ if (!ecap_qis(iommu->ecap))
+ return;
+
+ spin_lock_irqsave(&iommu->register_lock, flags);
+
+ sts = dmar_readq(iommu->reg + DMAR_GSTS_REG);
+ if (!(sts & DMA_GSTS_QIES))
+ goto end;
+
+ /*
+ * Give a chance to HW to complete the pending invalidation requests.
+ */
+ while ((readl(iommu->reg + DMAR_IQT_REG) !=
+ readl(iommu->reg + DMAR_IQH_REG)) &&
+ (DMAR_OPERATION_TIMEOUT > (get_cycles() - start_time)))
+ cpu_relax();
+
+ iommu->gcmd &= ~DMA_GCMD_QIE;
+
+ writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+ IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl,
+ !(sts & DMA_GSTS_QIES), sts);
+end:
+ spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+/*
* Enable Queued Invalidation interface. This is a must to support
* interrupt-remapping. Also used by DMA-remapping, which replaces
* register based IOTLB invalidation.
Index: tip/include/linux/intel-iommu.h
===================================================================
--- tip.orig/include/linux/intel-iommu.h
+++ tip/include/linux/intel-iommu.h
@@ -321,6 +321,7 @@ extern struct dmar_drhd_unit * dmar_find
extern int alloc_iommu(struct dmar_drhd_unit *drhd);
extern void free_iommu(struct intel_iommu *iommu);
extern int dmar_enable_qi(struct intel_iommu *iommu);
+extern void dmar_disable_qi(struct intel_iommu *iommu);
extern void qi_global_iec(struct intel_iommu *iommu);

extern int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid,
Index: tip/drivers/pci/intr_remapping.c
===================================================================
--- tip.orig/drivers/pci/intr_remapping.c
+++ tip/drivers/pci/intr_remapping.c
@@ -467,6 +467,33 @@ static int setup_intr_remapping(struct i
return 0;
}

+/*
+ * Disable Interrupt Remapping.
+ */
+static void disable_intr_remapping(struct intel_iommu *iommu)
+{
+ unsigned long flags;
+ u32 sts;
+
+ if (!ecap_ir_support(iommu->ecap))
+ return;
+
+ spin_lock_irqsave(&iommu->register_lock, flags);
+
+ sts = dmar_readq(iommu->reg + DMAR_GSTS_REG);
+ if (!(sts & DMA_GSTS_IRES))
+ goto end;
+
+ iommu->gcmd &= ~DMA_GCMD_IRE;
+ writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+ IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+ readl, !(sts & DMA_GSTS_IRES), sts);
+
+end:
+ spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
int __init enable_intr_remapping(int eim)
{
struct dmar_drhd_unit *drhd;

--