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

["zhichang.yuan" <yuanzhichang@hisilicon.com>]

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@hisilicon.com>
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

-- 
1.9.1