Re: [PATCH V8 0/7] LPC: legacy ISA I/O support

[dann frazier]

On Thu, Mar 30, 2017 at 9:26 AM, zhichang.yuan
<yuanzhichang@xxxxxxxxxxxxx> wrote:
> This patchset supports the IPMI-bt device attached to the Low-Pin-Count
> interface implemented on Hisilicon Hip06/Hip07 SoC.
>                         -----------
>                         | LPC host|
>                         |         |
>                         -----------
>                              |
>                 _____________V_______________LPC
>                   |                       |
>                   V                       V
>                                      ------------
>                                      |  BT(ipmi)|
>                                      ------------
>
> When master accesses those peripherals beneath the Hip06/Hip07 LPC, a specific
> LPC driver is needed to make LPC host generate the standard LPC I/O cycles with
> the target peripherals'I/O port addresses. But on curent arm64 world, there is
> no real I/O accesses. All the I/O operations through in/out pair are based on
> MMIO which is not satisfied the I/O mechanism on Hip06/Hip07 LPC.
> To solve this issue and keep the relevant existing peripherals' driver
> untouched, this patchset implements:
>   - introduces a generic I/O space management framwork, LIBIO, to support I/O
>     operations of both MMIO buses and the host controllers which access their
>     peripherals with host local I/O addresses;
>   - redefines the in/out accessors to provide unified interfaces for MMIO and
>     legacy I/O. Based on the LIBIO, the calling of in/out() from upper-layer
>     drivers, such as ipmi-si, will be redirected to the corresponding
>     device-specific I/O hooks to perfrom the I/O accesses.
> Based on this patch-set, all the I/O accesses to Hip06/Hip07 LPC peripherals can
> be supported without any changes on the existing ipmi-si driver.
>
> Changes from V7:
>   - Based on Arnd's comment, rename the LIBIO as LOGIC_PIO;
>   - Improved the mapping process in LOGIC_PIO to gain better efficiency when
>     redirecting the I/O accesses to right device driver;
>   - To reduce the impact on PCI MMIO to a minimum, add a new
>     CONFIG_INDIRECT_PIO for indirect-IO hosts/devices;
>   - Added a new ACPI handler for indirect-IO hosts/devices;
>   - Fixed the compile issues on V6;
>
> Changes from V6:
>   - According to the comments from Bjorn and Alex, merge PCI IO and indirect-IO
>     into a generic I/O space management, LIBIO;
>   - Adopted the '_DEP' to replace the platform bus notifier. In this way, we can
>     ensure the LPC peripherals' I/O resources had been translated to logical IO
>     before the LPC peripheral enumeration;
>   - Replaced the rwlock with rcu list based on Alex's suggestion;
>   - Applied relaxed write/read to LPC driver;
>   - Some bugs fixing and some optimazations based on the comments of V6;
>
> Changes from V5:
>   - Made the extio driver more generic and locate in lib/;
>   - Supported multiple indirect-IO bus instances;
>   - Extended the pci_register_io_range() to support indirect-IO, then dropped
>   the I/O reservation used in previous patchset;
>   - Reimplemented the ACPI LPC support;
>   - Fixed some bugs, including the compile error on other archs, the module
>   building failure found by Ming Lei, etc;
>
> Changes from V4:
>   - Some revises based on the comments from Bjorn, Rob on V4;
>   - Fixed the compile error on some platforms, such as openrisc;
>
> Changes from V3:
>   - UART support deferred to a separate patchset; This patchset only support
>   ipmi device under LPC;
>   - LPC bus I/O range is fixed to 0 ~ (PCIBIOS_MIN_IO - 1), which is separeted
>   from PCI/PCIE PIO space;
>   - Based on Arnd's remarks, removed the ranges property from Hip06 lpc dts and
>   added a new fixup function, of_isa_indirect_io(), to get the I/O address
>   directly from LPC dts configurations;
>   - Support in(w,l)/out(w,l) for Hip06 lpc I/O;
>   - Decouple the header file dependency on the gerenic io.h by defining in/out
>   as normal functions in c file;
>   - removed unused macro definitions in the LPC driver;
>
> Changes from V2:
>   - Support the PIO retrieval from the linux PIO generated by
>   pci_address_to_pio. This method replace the 4K PIO reservation in V2;
>   - Support the flat-tree earlycon;
>   - Some revises based on Arnd's remarks;
>   - Make sure the linux PIO range allocated to Hip06 LPC peripherals starts
>   from non-ZERO;
>
> Changes from V1:
>   - Support the ACPI LPC device;
>   - Optimize the dts LPC driver in ISA compatible mode;
>   - Reserve the IO range below 4K in avoid the possible conflict with PCI host
>   IO ranges;
>   - Support the LPC uart and relevant earlycon;
>
> V7 thread here: https://lkml.org/lkml/2017/3/12/279
> v6 thread here: https://lkml.org/lkml/2017/1/24/25
> v5 thread here: https://lkml.org/lkml/2016/11/7/955
> v4 thread here: https://lkml.org/lkml/2016/10/20/149
> v3 thread here: https://lkml.org/lkml/2016/9/14/326
> v2 thread here: https://lkml.org/lkml/2016/9/7/356
> v1 thread here: https://lkml.org/lkml/2015/12/29/154
>
>
> Signed-off-by: Zhichang Yuan <yuanzhichang@xxxxxxxxxxxxx>
> zhichang.yuan (6):
>   LIBIO: Introduce a generic PIO mapping method
>   PCI: Apply the new generic I/O management on PCI IO hosts
>   OF: Add missing I/O range exception for indirect-IO devices
>   LPC: Support the device-tree LPC host on Hip06/Hip07
>   ACPI: Support the probing on the devices which apply indirect-IO
>   LPC: Add the ACPI LPC support
>
>  .../arm/hisilicon/hisilicon-low-pin-count.txt      |  33 ++
>  MAINTAINERS                                        |   8 +
>  arch/arm64/boot/dts/hisilicon/hip06-d03.dts        |   4 +
>  arch/arm64/boot/dts/hisilicon/hip06.dtsi           |  14 +
>  arch/arm64/boot/dts/hisilicon/hip07-d05.dts        |   4 +
>  arch/arm64/boot/dts/hisilicon/hip07.dtsi           |  14 +
>  drivers/acpi/Makefile                              |   1 +
>  drivers/acpi/acpi_indirectio.c                     | 344 +++++++++++++
>  drivers/acpi/internal.h                            |   5 +
>  drivers/acpi/pci_root.c                            |   8 +-
>  drivers/acpi/scan.c                                |   1 +
>  drivers/bus/Kconfig                                |   9 +
>  drivers/bus/Makefile                               |   1 +
>  drivers/bus/hisi_lpc.c                             | 547 +++++++++++++++++++++
>  drivers/of/address.c                               |  95 +++-
>  drivers/pci/pci.c                                  | 104 +---
>  include/asm-generic/io.h                           |  50 ++
>  include/linux/logic_pio.h                          | 174 +++++++
>  include/linux/pci.h                                |   3 +-
>  lib/Kconfig                                        |  26 +
>  lib/Makefile                                       |   2 +
>  lib/logic_pio.c                                    | 413 ++++++++++++++++
>  22 files changed, 1758 insertions(+), 102 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
>  create mode 100644 drivers/acpi/acpi_indirectio.c
>  create mode 100644 drivers/bus/hisi_lpc.c
>  create mode 100644 include/linux/logic_pio.h
>  create mode 100644 lib/logic_pio.c

Booted up on a D05, was able to use the LPC-connected IPMI interface.

Tested-by: dann frazier <dann.frazier@xxxxxxxxxxxxx>