Commit 62dcee71 authored by Adrian Huang's avatar Adrian Huang Committed by Joerg Roedel
Browse files

iommu/amd: Replace two consecutive readl calls with one readq 



Optimize the reigster reading by using readq instead of the two
consecutive readl calls.

Signed-off-by: default avatarAdrian Huang <ahuang12@lenovo.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent bde9e6b9

drivers/iommu/amd_iommu_init.c

+1 −5
Original line number Diff line number Diff line
@@ -1718,7 +1718,6 @@ static const struct attribute_group *amd_iommu_groups[] = { 
static int __init iommu_init_pci(struct amd_iommu *iommu)

{

	int cap_ptr = iommu->cap_ptr;

	u32 low, high;

	int ret;



	iommu->dev = pci_get_domain_bus_and_slot(0, PCI_BUS_NUM(iommu->devid),
@@ -1736,10 +1735,7 @@ static int __init iommu_init_pci(struct amd_iommu *iommu) 
		amd_iommu_iotlb_sup = false;



	/* read extended feature bits */

	low  = readl(iommu->mmio_base + MMIO_EXT_FEATURES);

	high = readl(iommu->mmio_base + MMIO_EXT_FEATURES + 4);



	iommu->features = ((u64)high << 32) | low;

	iommu->features = readq(iommu->mmio_base + MMIO_EXT_FEATURES);



	if (iommu_feature(iommu, FEATURE_GT)) {

		int glxval;

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