[PATCH V4 0/3] ARM64 LPC: legacy ISA I/O support

From: zhichang.yuan
Date: Thu Oct 20 2016 - 04:50:04 EST


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 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@xxxxxxxxxxxxx>

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 | 36 ++
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/extio.c | 53 +++
drivers/bus/Kconfig | 8 +
drivers/bus/Makefile | 1 +
drivers/bus/hisi_lpc.c | 501 +++++++++++++++++++++
drivers/of/address.c | 47 +-
drivers/pci/pci.c | 6 +-
include/linux/of_address.h | 17 +
13 files changed, 804 insertions(+), 5 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

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1.9.1