[PATCH V2 0/4] ARM64 LPC: legacy ISA I/O support
Zhichang Yuan
yuanzhichang at hisilicon.com
Wed Sep 7 06:33:49 PDT 2016
From: "zhichang.yuan" <yuanzhichang at hisilicon.com>
This patch supports the 16550 compatible UART attached to the Low-Pin-Count
interface mplemented on Hisilicon Hip06 SoC. The periperals attached this LPC
include UART, BT, KCS, and so on.
-----------
| LPC host|
| |
-----------
|
_____________V_______________LPC
| |
V V
----------- ------------
| UART | | 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.
This patch set is built based on mainline v4.8-rc5;
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 (4):
ARM64 LPC: Indirect ISA port IO introduced
ARM64 LPC: LPC driver implementation on Hip06
ARM64 LPC: support serial based on low-pin-count
ARM64 LPC: support earlycon for UART connected to LPC
.../arm/hisilicon/hisilicon-low-pin-count.txt | 27 +
.../devicetree/bindings/serial/hisi-lpc-uart.txt | 50 ++
arch/arm64/Kconfig | 6 +
arch/arm64/include/asm/io.h | 109 ++++
arch/arm64/include/asm/pci.h | 1 -
drivers/bus/Kconfig | 8 +
drivers/bus/Makefile | 1 +
drivers/bus/hisi_lpc.c | 625 +++++++++++++++++++++
drivers/of/address.c | 3 +-
drivers/pci/pci.c | 6 +-
drivers/tty/serial/8250/8250_hisi_lpc.c | 104 ++++
drivers/tty/serial/8250/Kconfig | 9 +
drivers/tty/serial/8250/Makefile | 1 +
13 files changed, 945 insertions(+), 5 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
create mode 100644 Documentation/devicetree/bindings/serial/hisi-lpc-uart.txt
create mode 100644 drivers/bus/hisi_lpc.c
create mode 100644 drivers/tty/serial/8250/8250_hisi_lpc.c
--
1.9.1
More information about the linux-arm-kernel
mailing list