From f8bab73515ca5b392680bb033dceeb37b8463e95 Mon Sep 17 00:00:00 2001 From: mark gross Date: Fri, 8 Feb 2008 04:18:38 -0800 Subject: intel-iommu: PMEN support Add support for protected memory enable bits by clearing them if they are set at startup time. Some future boot loaders or firmware could have this bit set after it loads the kernel, and it needs to be cleared if DMA's are going to happen effectively. Signed-off-by: mark gross Acked-by: Muli Ben-Yehuda Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/pci/intel-iommu.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) (limited to 'drivers/pci/intel-iommu.c') diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 31fa6c92aa5..585e188c174 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -692,6 +692,23 @@ static int iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did, DMA_TLB_PSI_FLUSH, non_present_entry_flush); } +static void iommu_disable_protect_mem_regions(struct intel_iommu *iommu) +{ + u32 pmen; + unsigned long flags; + + spin_lock_irqsave(&iommu->register_lock, flags); + pmen = readl(iommu->reg + DMAR_PMEN_REG); + pmen &= ~DMA_PMEN_EPM; + writel(pmen, iommu->reg + DMAR_PMEN_REG); + + /* wait for the protected region status bit to clear */ + IOMMU_WAIT_OP(iommu, DMAR_PMEN_REG, + readl, !(pmen & DMA_PMEN_PRS), pmen); + + spin_unlock_irqrestore(&iommu->register_lock, flags); +} + static int iommu_enable_translation(struct intel_iommu *iommu) { u32 sts; @@ -745,7 +762,7 @@ static char *fault_reason_strings[] = "non-zero reserved fields in PTE", "Unknown" }; -#define MAX_FAULT_REASON_IDX ARRAY_SIZE(fault_reason_strings) - 1 +#define MAX_FAULT_REASON_IDX (ARRAY_SIZE(fault_reason_strings) - 1) char *dmar_get_fault_reason(u8 fault_reason) { @@ -1730,6 +1747,8 @@ int __init init_dmars(void) iommu_flush_context_global(iommu, 0); iommu_flush_iotlb_global(iommu, 0); + iommu_disable_protect_mem_regions(iommu); + ret = iommu_enable_translation(iommu); if (ret) goto error; -- cgit v1.2.3