[PATCH V4 0/8] PCI: ACPI: Setting up DMA coherency for PCI device from _CCA attribute

[Rafael J. Wysocki]

On Wednesday, October 28, 2015 09:54:23 PM Hanjun Guo wrote:
> Hi Rafael,
> 
> On 10/27/2015 11:27 PM, Rafael J. Wysocki wrote:
> > On Tuesday, October 27, 2015 09:52:50 AM Bjorn Helgaas wrote:
> >> Hi Suravee,
> >>
> >> On Wed, Oct 21, 2015 at 08:52:03AM -0700, Suravee Suthikulpanit wrote:
> >>> This patch series adds support to setup DMA coherency for PCI device using
> >>> the ACPI _CCA attribute. According to the ACPI spec, the _CCA attribute
> >>> is required for ARM64. Therefore, this patch is a pre-req for ACPI PCI
> >>> support for ARM64 which is currently in development.  Also, this should
> >>> not affect other architectures that does not define
> >>> CONFIG_ACPI_CCA_REQUIRED, since the default value is coherent.
> >>>
> >>> In the process, this series also introduces enum dev_dma_attr and a set
> >>> of APIs to query device DMA attribute. These APIs replace the obsolete
> >>> device_dma_is_coherent(), and acpi_check_dma().
> >>>
> >>> I have also included a patch from Jeremy posted here:
> >>>      http://www.spinics.net/lists/linux-usb/msg128582.html
> >>>
> >>> This patch series  has been tested on AMD Seattle RevB platform.
> >>> The git tree containing tested code and pre-req patches are posted here:
> >>>
> >>>      http://github.com/ssuthiku/linux.git pci-cca-v4
> >>>
> >>> Changes from V3: (https://lkml.org/lkml/2015/8/26/389)
> >>>      * Clean up suggested by Bjorn
> >>>      * Introduce enum dev_dma_attr
> >>>      * Replace device_dma_is_coherent() and acpi_check_dma() with
> >>>        new APIs.
> >>>
> >>> Changes from V2: (https://lkml.org/lkml/2015/8/25/549)
> >>>      * Return -ENOSUPP instead of -1 (per Rafael's suggestion)
> >>>      * Add WARN() when fail to setup DMA for PCI device when booting
> >>>        ACPI (per Arnd's suggestion)
> >>>      * Added Acked-by from Rob.
> >>>      * Minor clean up
> >>>
> >>> Changes from V1: (https://lkml.org/lkml/2015/8/13/182)
> >>>      * Include patch 1 from Jeremy to enable support for _CCA=0
> >>>      * Clean up acpi_check_dma() per Bjorn suggestions
> >>>      * Split the original V1 patch into two patches (patch 3 and 4)
> >>>
> >>> Jeremy Linton (1):
> >>>    Honor ACPI _CCA attribute setting
> >>>
> >>> Suravee Suthikulpanit (7):
> >>>    device property: Introducing enum dev_dma_attr
> >>>    acpi: Adding DMA Attribute APIs for ACPI Device
> >>>    device property: Adding DMA Attribute APIs for Generic Devices
> >>>    device property: acpi: Make use of the new DMA Attribute APIs
> >>>    device property: acpi: Remove unused DMA APIs
> >>>    PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
> >>>    PCI: ACPI: Add support for PCI device DMA coherency
> >>>
> >>>   drivers/acpi/acpi_platform.c              |  7 +++++-
> >>>   drivers/acpi/glue.c                       |  8 +++---
> >>>   drivers/acpi/scan.c                       | 42 +++++++++++++++++++++++++++++++
> >>>   drivers/base/property.c                   | 32 +++++++++++++++++------
> >>>   drivers/crypto/ccp/ccp-platform.c         |  9 ++++++-
> >>>   drivers/net/ethernet/amd/xgbe/xgbe-main.c |  9 ++++++-
> >>>   drivers/of/of_pci.c                       | 20 ---------------
> >>>   drivers/pci/probe.c                       | 36 ++++++++++++++++++++++++--
> >>>   include/acpi/acpi_bus.h                   | 36 +++-----------------------
> >>>   include/linux/acpi.h                      |  7 +++++-
> >>>   include/linux/of_pci.h                    |  3 ---
> >>>   include/linux/property.h                  | 10 +++++++-
> >>>   12 files changed, 145 insertions(+), 74 deletions(-)
> >>
> >> I had a couple minor comments.  It's sort of a toss-up, but this feels
> >> more ACPI-flavored than PCI, so I assume Rafael will take this whole
> >> series unless I hear otherwise.
> >
> > I'll do that.
> 
> If Suravee address the comments and send another version,
> an it be merged into 4.4?

Well, it is likely, but not guaranteed.

We're only a few days from the beginning of the merge window and I'm still
in Seoul.

Thanks,
Rafael