diff options
| author | Vasant Hegde <vasant.hegde@amd.com> | 2023-06-28 05:16:24 +0000 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2023-07-14 16:19:36 +0200 |
| commit | 274c2218b8b29ea2e0404f97d52040deb16d42dd (patch) | |
| tree | c3625caa3ed9601624ebfe8896fcfc98c64b1152 /drivers/iommu/amd/init.c | |
| parent | 386ae59bd7db4eafc74bdfdcf60182c2171aea2a (diff) | |
iommu/amd: Handle PPR log overflow
Some ATS-capable peripherals can issue requests to the processor to service
peripheral page requests using PCIe PRI (the Page Request Interface). IOMMU
supports PRI using PPR log buffer. IOMMU writes PRI request to PPR log
buffer and sends PPR interrupt to host. When there is no space in the
PPR log buffer (PPR log overflow) it will set PprOverflow bit in 'MMIO
Offset 2020h IOMMU Status Register'. When this happens PPR log needs to be
restarted as specified in IOMMU spec [1] section 2.6.2.
When handling the event it just resumes the PPR log without resizing
(similar to the way event and GA log overflow is handled).
Failing to handle PPR overflow means device may not work properly as
IOMMU stops processing new PPR events from device.
[1] https://www.amd.com/system/files/TechDocs/48882_3.07_PUB.pdf
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20230628051624.5792-3-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/amd/init.c')
| -rw-r--r-- | drivers/iommu/amd/init.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c index 7fab6ecb6295..e78d7c4f41bd 100644 --- a/drivers/iommu/amd/init.c +++ b/drivers/iommu/amd/init.c @@ -800,6 +800,17 @@ void amd_iommu_restart_ga_log(struct amd_iommu *iommu) } /* + * This function restarts ppr logging in case the IOMMU experienced + * PPR log overflow. + */ +void amd_iommu_restart_ppr_log(struct amd_iommu *iommu) +{ + amd_iommu_restart_log(iommu, "PPR", CONTROL_PPRINT_EN, + CONTROL_PPRLOG_EN, MMIO_STATUS_PPR_RUN_MASK, + MMIO_STATUS_PPR_OVERFLOW_MASK); +} + +/* * This function resets the command buffer if the IOMMU stopped fetching * commands from it. */ |