diff options
Diffstat (limited to 'drivers/iommu/amd/iommu.c')
| -rw-r--r-- | drivers/iommu/amd/iommu.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 7b4390a2f726..33c134a2b581 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -667,7 +667,14 @@ retry: event[0], event[1], event[2], event[3]); } - memset(__evt, 0, 4 * sizeof(u32)); + /* + * To detect the hardware errata 732 we need to clear the + * entry back to zero. This issue does not exist on SNP + * enabled system. Also this buffer is not writeable on + * SNP enabled system. + */ + if (!amd_iommu_snp_en) + memset(__evt, 0, 4 * sizeof(u32)); } static void iommu_poll_events(struct amd_iommu *iommu) @@ -736,10 +743,13 @@ static void iommu_poll_ppr_log(struct amd_iommu *iommu) entry[1] = raw[1]; /* - * To detect the hardware bug we need to clear the entry - * back to zero. + * To detect the hardware errata 733 we need to clear the + * entry back to zero. This issue does not exist on SNP + * enabled system. Also this buffer is not writeable on + * SNP enabled system. */ - raw[0] = raw[1] = 0UL; + if (!amd_iommu_snp_en) + raw[0] = raw[1] = 0UL; /* Update head pointer of hardware ring-buffer */ head = (head + PPR_ENTRY_SIZE) % PPR_LOG_SIZE; |