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

dann frazier
2017-03-30T21:42:24Z

On Thu, Mar 30, 2017 at 9:26 AM, zhichang.yuan
<yuanzhichang@hisilicon.com> wrote:
> 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

Booted up on a D05, was able to use the LPC-connected IPMI interface.

Tested-by: dann frazier <dann.frazier@canonical.com>