RE: [PATCH V8 0/9] Support for ARM64 ACPI based PCI host controller

Gabriele Paoloni
2016-06-01T07:37:47Z

Hi all

In v7 thread Lorenzo has summarized a roadmap to
get ACPI support for PCI controllers upstream.

The second point of the roadmap was
<< 2) In a real world (1) is not enough. Some ARM64 platforms, not entirely
ECAM compliant, already shipped with the corresponding firmware that
we can't update. HW has ECAM quirks and to work around it in the kernel
we put forward many solutions to the problem, it is time we found a
solution (when, of course, (1) is completed and upstream).
Using the MCFG table OEMID matching floated around in this thread
would work fine for most of the platforms (and cross-OS) that have
shipped with HW ECAM quirks, so I think that's the starting point for
our solution and that's how we can sort this out, _today_.

The solution is a trivial look-up table:
MCFG OEMID <-> PCI config space ops >>

I think maybe it is worth to post this quirk mechanism as RFC on
top of this v8 patchset, so that we can start to review it and
make some progress on the quirks.

If you agree I think Jon can tell who's the best person to
push the quirk RFC (as my understanding is that this mechanism
is currently used by some platforms deployed on the market...)

Thanks

Gab

> -----Original Message-----
> From: linux-pci-owner@vger.kernel.org [mailto:linux-pci-
> owner@vger.kernel.org] On Behalf Of Tomasz Nowicki
> Sent: 30 May 2016 16:14
> To: helgaas@kernel.org; arnd@arndb.de; will.deacon@arm.com;
> catalin.marinas@arm.com; rafael@kernel.org; hanjun.guo@linaro.org;
> Lorenzo.Pieralisi@arm.com; okaya@codeaurora.org; jchandra@broadcom.com
> Cc: robert.richter@caviumnetworks.com; mw@semihalf.com;
> Liviu.Dudau@arm.com; ddaney@caviumnetworks.com; Wangyijing;
> Suravee.Suthikulpanit@amd.com; msalter@redhat.com; linux-
> pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-
> acpi@vger.kernel.org; linux-kernel@vger.kernel.org; linaro-
> acpi@lists.linaro.org; jcm@redhat.com; andrea.gallo@linaro.org;
> dhdang@apm.com; jeremy.linton@arm.com; liudongdong (C);
> cov@codeaurora.org; Tomasz Nowicki
> Subject: [PATCH V8 0/9] Support for ARM64 ACPI based PCI host
> controller
>
> From the functionality point of view this series may be split into the
> following logic parts:
> 1. Export ECAM API and add parent device to pci_config_window
> 2. Add IO resources handling to PCI core code
> 3. Support for generic domain assignment based on ACPI
> 4. New MCFG driver
> 5. Implement ARM64 ACPI based PCI host controller driver under
> arch/arm64/
>
> Patches has been built on top of 4.7-rc1 and can be found here:
> git@github.com:semihalf-nowicki-tomasz/linux.git (pci-acpi-v8)
>
> This has been tested on Cavium ThunderX server. Any help in reviewing
> and
> testing is very appreciated.
>
> v7 -> v8
> - move code from drivers/acpi/pci_root_generic.c to
> arch/arm64/kernel/pci.c
> - minor changes around domain assignment
> - pci_mcfg.c improvements for parsing MCFG tables and lookup its
> entries
>
> v6 -> v7
> - drop quirks handling
> - changes for ACPI companion and domain number assignment approach
> - implement arch pcibios_{add|remove}_bus and call
> acpi_pci_{add|remove}_bus from there
> - cleanups around nomenclature
> - use resources oriented API for ECAM
> - fix for based address calculation before mapping ECAM region
> - remove useless lock for MCFG lookup
> - move MCFG stuff to separated file pci_mcfg.c
> - drop MCFG entries caching
> - rebase against 4.6-rc7
>
> v5 -> v6
> - drop idea of x86 MMCONFIG code refactoring
> - integrate JC's patches which introduce new ECAM API:
> https://lkml.org/lkml/2016/4/11/907
> git: https://github.com/jchandra-brcm/linux/ (arm64-acpi-pci-v3)
> - integrate Sinan's fix for releasing IO resources, see patch [06/13]
> - added ACPI support for ThunderX ECAM and PEM drivers
> - rebase against 4.6-rc2
>
> v4 -> v5
> - drop MCFG refactoring group patches 1-6 from series v4 and integrate
> Jayachandran's patch
> https://patchwork.ozlabs.org/patch/575525/
> - rewrite PCI legacy IRQs allocation
> - squash two patches 11 and 12 from series v4, fixed bisection issue
> - changelog improvements
> - rebase against 4.5-rc3
>
> v3 -> v4
> - drop Jiang's fix
> http://lkml.iu.edu/hypermail/linux/kernel/1601.1/04318.html
> - add Lorenzo's fix patch 19/24
> - ACPI PCI bus domain number assigning cleanup
> - change resource management, we now claim and reassign resources
> - improvements for applying quirks
> - drop Matthew's http://www.spinics.net/lists/linux-pci/msg45950.html
> dependency
> - rebase against 4.5-rc1
>
> v2 -> v3
> - fix legacy IRQ assigning and IO ports registration
> - remove reference to arch specific companion device for ia64
> - move ACPI PCI host controller driver to pci_root.c
> - drop generic domain assignment for x86 and ia64 as I am not
> able to run all necessary test variants
> - drop patch which cleaned legacy IRQ assignment since it belongs to
> Mathew's series:
> https://patchwork.ozlabs.org/patch/557504/
> - extend MCFG quirk code
> - rebase against 4.4
>
> v1 -> v2
> - move non-arch specific piece of code to dirver/acpi/ directory
> - fix IO resource handling
> - introduce PCI config accessors quirks matching
> - moved ACPI_COMPANION_SET to generic code
>
> v1 - https://lkml.org/lkml/2015/10/27/504
> v2 - https://lkml.org/lkml/2015/12/16/246
> v3 - http://lkml.iu.edu/hypermail/linux/kernel/1601.1/04308.html
> v4 - https://lkml.org/lkml/2016/2/4/646
> v5 - https://lkml.org/lkml/2016/2/16/426
> v6 - https://lkml.org/lkml/2016/4/15/594
>
> Jayachandran C (2):
> PCI: ecam: move ecam.h to linux/include/pci-ecam.h
> PCI: ecam: Add parent device field to pci_config_window
>
> Tomasz Nowicki (7):
> pci: Add new function to unmap IO resources.
> acpi, pci: Support IO resources when parsing PCI host bridge
> resources.
> pci, acpi: add acpi hook to assign domain number.
> arm64, pci, acpi: ACPI support for legacy IRQs parsing and
> consolidation with DT code.
> acpi: Add generic MCFG table handling
> arm64, pci, acpi: Provide ACPI-specific prerequisites for PCI bus
> enumeration.
> pci, acpi: ARM64 support for ACPI based generic PCI host controller
>
> arch/arm64/Kconfig | 2 +
> arch/arm64/kernel/pci.c | 143
> ++++++++++++++++++++++++++++++++++--
> drivers/acpi/Kconfig | 3 +
> drivers/acpi/Makefile | 1 +
> drivers/acpi/pci_mcfg.c | 94 ++++++++++++++++++++++++
> drivers/acpi/pci_root.c | 39 ++++++++++
> drivers/pci/ecam.c | 6 +-
> drivers/pci/ecam.h | 67 -----------------
> drivers/pci/host/pci-host-common.c | 3 +-
> drivers/pci/host/pci-host-generic.c | 3 +-
> drivers/pci/host/pci-thunder-ecam.c | 3 +-
> drivers/pci/host/pci-thunder-pem.c | 6 +-
> drivers/pci/pci.c | 29 +++++++-
> include/linux/pci-acpi.h | 2 +
> include/linux/pci-ecam.h | 67 +++++++++++++++++
> include/linux/pci.h | 9 ++-
> 16 files changed, 387 insertions(+), 90 deletions(-)
> create mode 100644 drivers/acpi/pci_mcfg.c
> delete mode 100644 drivers/pci/ecam.h
> create mode 100644 include/linux/pci-ecam.h
>
> --
> 1.9.1
>
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