From 1531a6a6b81a4e6f9eec9a5608758a6ea14b96e0 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 16 Mar 2009 17:04:57 -0700 Subject: x86, dmar: start with sane state while enabling dma and interrupt-remapping Impact: cleanup/sanitization Start from a sane state while enabling dma and interrupt-remapping, by clearing the previous recorded faults and disabling previously enabled queued invalidation and interrupt-remapping. Signed-off-by: Suresh Siddha Signed-off-by: H. Peter Anvin --- drivers/pci/intel-iommu.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'drivers/pci/intel-iommu.c') diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 25fc1df486bb..ef167b8b047d 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -1855,11 +1855,40 @@ static int __init init_dmars(void) } } + /* + * Start from the sane iommu hardware state. + */ for_each_drhd_unit(drhd) { if (drhd->ignored) continue; iommu = drhd->iommu; + + /* + * If the queued invalidation is already initialized by us + * (for example, while enabling interrupt-remapping) then + * we got the things already rolling from a sane state. + */ + if (iommu->qi) + continue; + + /* + * Clear any previous faults. + */ + dmar_fault(-1, iommu); + /* + * Disable queued invalidation if supported and already enabled + * before OS handover. + */ + dmar_disable_qi(iommu); + } + + for_each_drhd_unit(drhd) { + if (drhd->ignored) + continue; + + iommu = drhd->iommu; + if (dmar_enable_qi(iommu)) { /* * Queued Invalidate not enabled, use Register Based -- cgit v1.2.3