[PATCH 5/5] x86/amd-iommu: Add ATS enable/disable code

From: Joerg Roedel
Date: Fri Apr 08 2011 - 04:17:46 EST


This patch adds the necessary code to the AMD IOMMU driver
for enabling and disabling the ATS capability on a device
and to setup the IOMMU data structures correctly.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/include/asm/amd_iommu_types.h | 2 ++
arch/x86/kernel/amd_iommu.c | 29 +++++++++++++++++++++++------
2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index cb811c9..7434377 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -216,6 +216,8 @@
#define IOMMU_PTE_IR (1ULL << 61)
#define IOMMU_PTE_IW (1ULL << 62)

+#define DTE_FLAG_IOTLB 0x01
+
#define IOMMU_PAGE_MASK (((1ULL << 52) - 1) & ~0xfffULL)
#define IOMMU_PTE_PRESENT(pte) ((pte) & IOMMU_PTE_P)
#define IOMMU_PTE_PAGE(pte) (phys_to_virt((pte) & IOMMU_PAGE_MASK))
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index f3ce433..ad97fd6 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1452,17 +1452,22 @@ static bool dma_ops_domain(struct protection_domain *domain)
return domain->flags & PD_DMA_OPS_MASK;
}

-static void set_dte_entry(u16 devid, struct protection_domain *domain)
+static void set_dte_entry(u16 devid, struct protection_domain *domain, bool ats)
{
u64 pte_root = virt_to_phys(domain->pt_root);
+ u32 flags = 0;

pte_root |= (domain->mode & DEV_ENTRY_MODE_MASK)
<< DEV_ENTRY_MODE_SHIFT;
pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | IOMMU_PTE_TV;

- amd_iommu_dev_table[devid].data[2] = domain->id;
- amd_iommu_dev_table[devid].data[1] = upper_32_bits(pte_root);
- amd_iommu_dev_table[devid].data[0] = lower_32_bits(pte_root);
+ if (ats)
+ flags |= DTE_FLAG_IOTLB;
+
+ amd_iommu_dev_table[devid].data[3] |= flags;
+ amd_iommu_dev_table[devid].data[2] = domain->id;
+ amd_iommu_dev_table[devid].data[1] = upper_32_bits(pte_root);
+ amd_iommu_dev_table[devid].data[0] = lower_32_bits(pte_root);
}

static void clear_dte_entry(u16 devid)
@@ -1479,16 +1484,22 @@ static void do_attach(struct device *dev, struct protection_domain *domain)
{
struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
+ struct pci_dev *pdev;
+ bool ats = false;
u16 devid;

devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
dev_data = get_dev_data(dev);
+ pdev = to_pci_dev(dev);
+
+ if (amd_iommu_iotlb_sup)
+ ats = pci_enable_ats(pdev, PAGE_SHIFT) == 0;

/* Update data structures */
dev_data->domain = domain;
list_add(&dev_data->list, &domain->dev_list);
- set_dte_entry(devid, domain);
+ set_dte_entry(devid, domain, ats);

/* Do reference counting */
domain->dev_iommu[iommu->index] += 1;
@@ -1502,11 +1513,13 @@ static void do_detach(struct device *dev)
{
struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
+ struct pci_dev *pdev;
u16 devid;

devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
dev_data = get_dev_data(dev);
+ pdev = to_pci_dev(dev);

/* decrease reference counters */
dev_data->domain->dev_iommu[iommu->index] -= 1;
@@ -1517,6 +1530,9 @@ static void do_detach(struct device *dev)
list_del(&dev_data->list);
clear_dte_entry(devid);

+ if (amd_iommu_iotlb_sup && pci_ats_enabled(pdev))
+ pci_disable_ats(pdev);
+
/* Flush the DTE entry */
device_flush_dte(dev);
}
@@ -1795,8 +1811,9 @@ static void update_device_table(struct protection_domain *domain)
struct iommu_dev_data *dev_data;

list_for_each_entry(dev_data, &domain->dev_list, list) {
+ struct pci_dev *pdev = to_pci_dev(dev_data->dev);
u16 devid = get_device_id(dev_data->dev);
- set_dte_entry(devid, domain);
+ set_dte_entry(devid, domain, pci_ats_enabled(pdev));
}
}

--
1.7.1


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