[PATCH V6 0/5] LPC: legacy ISA I/O support

From: zhichang.yuan
Date: Tue Jan 24 2017 - 01:34:38 EST

This patch supports the IPMI-bt device attached to the Low-Pin-Count interface
implemented on Hisilicon Hip06/Hip07 SoC.
| LPC host|
| |
| |
| BT(ipmi)|

When master accesses those peripherals beneath the Hip06 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 LPC.
To solve this issue and keep the relevant existing peripherals' driver
untouched, 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 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;

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 (5):
LIB: Indirect ISA/LPC port IO introduced
PCI: Adapt pci_register_io_range() for indirect-IO and PCI I/O
OF: Add missing I/O range exception for indirect-IO devices
LPC: Support the device-tree LPC host on Hip06/Hip07
LPC: Add the ACPI LPC support

.../arm/hisilicon/hisilicon-low-pin-count.txt | 33 ++
arch/arm64/boot/dts/hisilicon/hip06-d03.dts | 4 +
arch/arm64/boot/dts/hisilicon/hip06.dtsi | 14 +
drivers/acpi/pci_root.c | 12 +-
drivers/bus/Kconfig | 8 +
drivers/bus/Makefile | 1 +
drivers/bus/hisi_lpc.c | 625 +++++++++++++++++++++
drivers/of/address.c | 95 +++-
drivers/pci/pci.c | 44 +-
include/asm-generic/io.h | 50 ++
include/linux/extio.h | 89 +++
include/linux/io.h | 1 +
include/linux/pci.h | 7 +-
lib/Kconfig | 8 +
lib/Makefile | 2 +
lib/extio.c | 375 +++++++++++++
17 files changed, 1342 insertions(+), 35 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
create mode 100644 drivers/bus/hisi_lpc.c
create mode 100644 include/linux/extio.h
create mode 100644 lib/extio.c