[PATCH V5 0/3] ARM64 LPC: legacy ISA I/O support

zhichang.yuan yuanzhichang at hisilicon.com
Mon Nov 7 19:47:06 PST 2016


This patch supports the IPMI-bt device attached to the Low-Pin-Count interface
implemented on Hisilicon Hip06 SoC.
	                -----------
			| LPC host|
	                |         |
	                -----------
	                     |
 	        _____________V_______________LPC
                  |			  |
                  V	                  V
			             ------------
			             |  BT(ipmi)|
			             ------------

When master accesses those periperals beneath the Hip06 LPC, a specific LPC
driver is needed to make LPC host generate the standard LPC I/O cycles with
the target periperals'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 LPC.
To solve this issue and keep the relevant existing peripherals' driver
unchanged, this patch set redefines the in/out pair to support both the IO
operations for Hip06 LPC and the original MMIO. The way specific to Hip06 is
named as indirect-IO in this patchset.

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;

Signed-off-by: Zhichang Yuan <yuanzhichang at hisilicon.com>

zhichang.yuan (3):
  ARM64 LPC: Indirect ISA port IO introduced
  ARM64 LPC: Add missing range exception for special ISA
  ARM64 LPC: LPC driver implementation on Hip06

 .../arm/hisilicon/hisilicon-low-pin-count.txt      |  31 ++
 MAINTAINERS                                        |   8 +
 arch/arm64/Kconfig                                 |   6 +
 arch/arm64/include/asm/extio.h                     |  94 ++++
 arch/arm64/include/asm/io.h                        |  35 ++
 arch/arm64/kernel/Makefile                         |   1 +
 arch/arm64/kernel/extio.c                          |  52 +++
 drivers/bus/Kconfig                                |   8 +
 drivers/bus/Makefile                               |   1 +
 drivers/bus/hisi_lpc.c                             | 501 +++++++++++++++++++++
 drivers/of/address.c                               |  56 ++-
 drivers/pci/pci.c                                  |   6 +-
 include/linux/of_address.h                         |  17 +
 include/linux/pci.h                                |   8 +
 14 files changed, 820 insertions(+), 4 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
 create mode 100644 arch/arm64/include/asm/extio.h
 create mode 100644 arch/arm64/kernel/extio.c
 create mode 100644 drivers/bus/hisi_lpc.c

-- 
1.9.1




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