From 5d990b627537e59a3a2f039ff588a4750e9c1a6a Mon Sep 17 00:00:00 2001 From: Chris Wright Date: Fri, 4 Dec 2009 12:15:21 -0800 Subject: PCI: add pci_request_acs Commit ae21ee65e8bc228416bbcc8a1da01c56a847a60c "PCI: acs p2p upsteram forwarding enabling" doesn't actually enable ACS. Add a function to pci core to allow an IOMMU to request that ACS be enabled. The existing mechanism of using iommu_found() in the pci core to know when ACS should be enabled doesn't actually work due to initialization order; iommu has only been detected not initialized. Have Intel and AMD IOMMUs request ACS, and Xen does as well during early init of dom0. Cc: Allen Kay Cc: David Woodhouse Cc: Jeremy Fitzhardinge Cc: Joerg Roedel Signed-off-by: Chris Wright Signed-off-by: Jesse Barnes --- drivers/pci/dmar.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/pci/dmar.c') diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index e01ca4d6b3e6..0e98f6b6f515 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -614,8 +614,11 @@ void __init detect_intel_iommu(void) #endif #ifdef CONFIG_DMAR if (ret && !no_iommu && !iommu_detected && !swiotlb && - !dmar_disabled) + !dmar_disabled) { iommu_detected = 1; + /* Make sure ACS will be enabled */ + pci_request_acs(); + } #endif } early_acpi_os_unmap_memory(dmar_tbl, dmar_tbl_size); -- cgit v1.2.3