RE: [PATCH v13 0/9] ACPI/IORT: Support for IORT RMR node

[Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>]

> -----Original Message-----
> From: Steven Price [mailto:steven.price@arm.com]
> Sent: 17 June 2022 13:42
> To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>;
> linux-arm-kernel@lists.infradead.org; linux-acpi@vger.kernel.org;
> iommu@lists.linux-foundation.org
> Cc: Linuxarm <linuxarm@huawei.com>; lorenzo.pieralisi@arm.com;
> joro@8bytes.org; robin.murphy@arm.com; will@kernel.org; wanghuiqiang
> <wanghuiqiang@huawei.com>; Guohanjun (Hanjun Guo)
> <guohanjun@huawei.com>; Sami.Mujawar@arm.com; jon@solid-run.com;
> eric.auger@redhat.com; laurentiu.tudor@nxp.com; hch@infradead.org
> Subject: Re: [PATCH v13 0/9] ACPI/IORT: Support for IORT RMR node
> 
> On 15/06/2022 11:10, Shameer Kolothum wrote:
> > Hi
> >
> > v12 --> v13
> >   -No changes. Rebased to 5.19-rc1.
> >   -Picked up tags received from Laurentiu, Hanjun and Will. Thanks!.
> 
> You've already got my Tested-by tags, but just to confirm I gave this a
> spin and it works fine.

Thanks Steve.

I think the series is now in a good shape to be merged.

Hi Will/Robin,

Appreciate, if you could please take a look at the remaining SMMU related 
patches(7-9) and provide your approval?

Thanks,
Shameer

> 
> Thanks,
> 
> Steve
> 
> >
> > Thanks,
> > Shameer
> >
> > From old:
> > We have faced issues with 3408iMR RAID controller cards which
> > fail to boot when SMMU is enabled. This is because these
> > controllers make use of host memory for various caching related
> > purposes and when SMMU is enabled the iMR firmware fails to
> > access these memory regions as there is no mapping for them.
> > IORT RMR provides a way for UEFI to describe and report these
> > memory regions so that the kernel can make a unity mapping for
> > these in SMMU.
> >
> > Change History:
> >
> > v11 --> v12
> >   -Minor fix in patch #4 to address the issue reported by the kernel test
> robot.
> >   -Added R-by tags by Christoph(patch #1) and Lorenzo(patch #4).
> >   -Added T-by from Steve to all relevant patches. Many thanks!.
> >
> > v10 --> v11
> >  -Addressed Christoph's comments. We now have a  callback to
> >   struct iommu_resv_region to free all related memory and also dropped
> >   the FW specific union and now has a container struct
> iommu_iort_rmr_data.
> >   See patches #1 & #4
> >  -Added R-by from Christoph.
> >  -Dropped R-by from Lorenzo for patches #4 & #5 due to the above
> changes.
> >  -Also dropped T-by from Steve and Laurentiu. Many thanks for your test
> >   efforts. I have done basic sanity testing on my platform but please
> >   do it again at your end.
> >
> > v9 --> v10
> >  - Dropped patch #1 ("Add temporary RMR node flag definitions") since
> >    the ACPICA header updates patch is now in the mailing list
> >  - Based on the suggestion from Christoph, introduced a
> >    resv_region_free_fw_data() callback in struct iommu_resv_region and
> >    used that to free RMR specific memory allocations.
> >
> > v8 --> v9
> >  - Adressed comments from Robin on interfaces.
> >  - Addressed comments from Lorenzo.
> >
> > v7 --> v8
> >   - Patch #1 has temp definitions for RMR related changes till
> >     the ACPICA header changes are part of kernel.
> >   - No early parsing of RMR node info and is only parsed at the
> >     time of use.
> >   - Changes to the RMR get/put API format compared to the
> >     previous version.
> >   - Support for RMR descriptor shared by multiple stream IDs.
> >
> > v6 --> v7
> >  -fix pointed out by Steve to the SMMUv2 SMR bypass install in patch #8.
> >
> > v5 --> v6
> > - Addressed comments from Robin & Lorenzo.
> >   : Moved iort_parse_rmr() to acpi_iort_init() from
> >     iort_init_platform_devices().
> >   : Removed use of struct iort_rmr_entry during the initial
> >     parse. Using struct iommu_resv_region instead.
> >   : Report RMR address alignment and overlap errors, but continue.
> >   : Reworked arm_smmu_init_bypass_stes() (patch # 6).
> > - Updated SMMUv2 bypass SMR code. Thanks to Jon N (patch #8).
> > - Set IOMMU protection flags(IOMMU_CACHE, IOMMU_MMIO) based
> >   on Type of RMR region. Suggested by Jon N.
> >
> > v4 --> v5
> >  -Added a fw_data union to struct iommu_resv_region and removed
> >   struct iommu_rmr (Based on comments from Joerg/Robin).
> >  -Added iommu_put_rmrs() to release mem.
> >  -Thanks to Steve for verifying on SMMUv2, but not added the Tested-by
> >   yet because of the above changes.
> >
> > v3 -->v4
> > -Included the SMMUv2 SMR bypass install changes suggested by
> >  Steve(patch #7)
> > -As per Robin's comments, RMR reserve implementation is now
> >  more generic  (patch #8) and dropped v3 patches 8 and 10.
> > -Rebase to 5.13-rc1
> >
> > RFC v2 --> v3
> >  -Dropped RFC tag as the ACPICA header changes are now ready to be
> >   part of 5.13[0]. But this series still has a dependency on that patch.
> >  -Added IORT E.b related changes(node flags, _DSM function 5 checks for
> >   PCIe).
> >  -Changed RMR to stream id mapping from M:N to M:1 as per the spec
> and
> >   discussion here[1].
> >  -Last two patches add support for SMMUv2(Thanks to Jon Nettleton!)
> >
> > Jon Nettleton (1):
> >   iommu/arm-smmu: Get associated RMR info and install bypass SMR
> >
> > Shameer Kolothum (8):
> >   iommu: Introduce a callback to struct iommu_resv_region
> >   ACPI/IORT: Make iort_iommu_msi_get_resv_regions() return void
> >   ACPI/IORT: Provide a generic helper to retrieve reserve regions
> >   ACPI/IORT: Add support to retrieve IORT RMR reserved regions
> >   ACPI/IORT: Add a helper to retrieve RMR info directly
> >   iommu/arm-smmu-v3: Introduce strtab init helper
> >   iommu/arm-smmu-v3: Refactor arm_smmu_init_bypass_stes() to force
> >     bypass
> >   iommu/arm-smmu-v3: Get associated RMR info and install bypass STE
> >
> >  drivers/acpi/arm64/iort.c                   | 360
> ++++++++++++++++++--
> >  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c |  78 ++++-
> >  drivers/iommu/arm/arm-smmu/arm-smmu.c       |  52 +++
> >  drivers/iommu/dma-iommu.c                   |   2 +-
> >  drivers/iommu/iommu.c                       |  16 +-
> >  include/linux/acpi_iort.h                   |  14 +-
> >  include/linux/iommu.h                       |  10 +
> >  7 files changed, 486 insertions(+), 46 deletions(-)
> >
>