diff options
Diffstat (limited to 'drivers/iommu/amd/init.c')
| -rw-r--r-- | drivers/iommu/amd/init.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 35f220704bef..662b01eaf0f2 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -359,6 +359,29 @@ static void iommu_set_exclusion_range(struct amd_iommu *iommu) &entry, sizeof(entry)); } +static void iommu_set_cwwb_range(struct amd_iommu *iommu) +{ + u64 start = iommu_virt_to_phys((void *)iommu->cmd_sem); + u64 entry = start & PM_ADDR_MASK; + + if (!iommu_feature(iommu, FEATURE_SNP)) + return; + + /* Note: + * Re-purpose Exclusion base/limit registers for Completion wait + * write-back base/limit. + */ + memcpy_toio(iommu->mmio_base + MMIO_EXCL_BASE_OFFSET, + &entry, sizeof(entry)); + + /* Note: + * Default to 4 Kbytes, which can be specified by setting base + * address equal to the limit address. + */ + memcpy_toio(iommu->mmio_base + MMIO_EXCL_LIMIT_OFFSET, + &entry, sizeof(entry)); +} + /* Programs the physical address of the device table into the IOMMU hardware */ static void iommu_set_device_table(struct amd_iommu *iommu) { @@ -1884,6 +1907,9 @@ static int __init amd_iommu_init_pci(void) ret = iommu_init_pci(iommu); if (ret) break; + + /* Need to setup range after PCI init */ + iommu_set_cwwb_range(iommu); } /* |