This patch series implements Linux driver support for the Rshim
component on Mellanox BlueField ARM SoC.
1. Overview of the Rshim component
The Rshim component provides a connection among different other
components of the SoC and can be accessed externally via USB or
PCIe. USB access is available on standard appliance and SmartNIC.
PCIe access is for SmartNIC only.
>From user perspective, Rshim provides the following
functionalities.
1.1 Boot FIFO
The Boot FIFO is polled by the boot ROM. At a later booting
phase it's read by UEFI as well to load the Linux kernel.
The Boot FIFO is a one-way direction FIFO. The data could
come from different sources.
a) On-chip eMMC, which is the default configuration.
After chip reset, HW will generate eMMC commands, which
triggers the boot stream on the eMMC boot partition to show
up in Boot FIFO.
This one doesn't need any Linux driver.
b) Injected externally from USB or PCIe.
External host could overwrite the boot mode and inject
boot stream into the Boot FIFO over USB or PCIe. It's
used in board bring-up, fault recovering or debugging.
This one usually needs driver support in the external host.
1.2 TmFifo
TmFifo are FIFOs which can be used for communication between
the SoC ARM core and the external side. Each direction has its
own FIFO.
TmFifo needs driver support on both the SoC side and the
external host side.
1.3 Rshim register space access
Rshim register space could be accessed externally via
USB or PCIe. It's used for configuration, debugging, etc.
More specifically, it could be used to access the ARM
CoreSight component which could do on-chip debugging,
such as for boot loader, drivers, or crash information
collection.
This one needs driver support from external host.
2. Driver Introduction
This patch series provides several drivers.
*) Patch 1/9 ~ 4/9 (tmfifo.c, tmfifo_regs.h, Kconfig, Makefile)
They provide Linux driver support for the TmFifo on the
SoC side (see above 1.2).
*) Patch 5/9 ~ 9/9
They provide Linux driver support for the external host.
- Patch 5/9 (rshim.c, rshim.h, rshim_regs.h, Makefile)
It provides common functionalities and register access
to the RShim component. Several character devices are
created like below for easy user-access.
/dev/rshim<N>/boot
This device file is used to inject boot stream into
the Boot FIFO, such as
'cat boot-image > /dev/rshim<N>/boot'
This one is to implement the above function 1.1.b
/dev/rshim<N>/rshim
This device file is used to access Rshim register
space like a plat file.
/dev/rshim<N>/console
This device file is used to access the virtual
console to the SoC via the TmFifo (see above
functionality 1.2). It can be used by any standard tools
like minicom, screen, etc.
- Patch 6/9 (rshim_net.c)
This patch provides virtual networking support over
the Rshim TmFifo (see above functionality 1.2).
- Patch 7/9 (rshim_usb.c)
This is the USB backend driver, which implements the
details to access the RShim component via USB. It supports
endpoints, USB bulk-transfer and interrupts. After loaded
by ACPI, it triggers the loading of the common driver
and network driver, and provides low-level APIs to the
common driver.
Below is an example of the networking calling stack.
Linux Network Stack --> virtio_net --> rshim_net -->
rshim common driver --> rshim USB backend driver
- Patch 8/9 (rshim_pcie.c)
This is the PCIe backend driver, which implements the
details to access the RShim component via PCIe when
the HCA firmware is ready. In such case, the Rshim component
is exposed as a standard PCIe PF and it's register space
can be mapped in BAR0.
Linux Network Stack --> virtio_net --> rshim_net -->
rshim common driver --> rshim PCIe backend driver
- Patch 9/9 (rshim_pcie_lf.c)
Similarly, this is another PCIe backend driver, but provides
slow access when the HCA firmware is not ready. In such as,
the BAR0 mapping is not available. The Rshim register access
is done via a slow access gateway. The below calling stack
is also similar.
Linux Network Stack --> virtio_net --> rshim_net -->
rshim common driver --> rshim PCIe livefish backend driver
Liming Sun (9):
soc: Add TmFifo driver for Mellanox BlueField Soc
arm64: Add Mellanox BlueField SoC config option
dt-bindings: soc: Add TmFifo binding for Mellanox BlueField SoC
MAINTAINERS: Add entry for Mellanox Bluefield Soc
soc: mellanox: host: Add the common host side Rshim driver
soc: mellanox: host: Add networking support over Rshim
soc: mellanox: host: Add the Rshim USB backend driver
soc: mellanox: host: Add the Rshim PCIe backend driver
soc: mellanox: host: Add the Rshim PCIe live-fish backend driver
.../devicetree/bindings/soc/mellanox/tmfifo.txt | 23 +
MAINTAINERS | 8 +
arch/arm64/Kconfig.platforms | 6 +
arch/arm64/configs/defconfig | 1 +
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/mellanox/Kconfig | 26 +
drivers/soc/mellanox/Makefile | 6 +
drivers/soc/mellanox/host/Makefile | 2 +
drivers/soc/mellanox/host/rshim.c | 2673 ++++++++++++++++++++
drivers/soc/mellanox/host/rshim.h | 361 +++
drivers/soc/mellanox/host/rshim_net.c | 834 ++++++
drivers/soc/mellanox/host/rshim_pcie.c | 478 ++++
drivers/soc/mellanox/host/rshim_pcie_lf.c | 695 +++++
drivers/soc/mellanox/host/rshim_regs.h | 152 ++
drivers/soc/mellanox/host/rshim_usb.c | 1035 ++++++++
drivers/soc/mellanox/tmfifo.c | 1244 +++++++++
drivers/soc/mellanox/tmfifo_regs.h | 76 +
18 files changed, 7622 insertions(+)
create mode 100644 Documentation/devicetree/bindings/soc/mellanox/tmfifo.txt
create mode 100644 drivers/soc/mellanox/Kconfig
create mode 100644 drivers/soc/mellanox/Makefile
create mode 100644 drivers/soc/mellanox/host/Makefile
create mode 100644 drivers/soc/mellanox/host/rshim.c
create mode 100644 drivers/soc/mellanox/host/rshim.h
create mode 100644 drivers/soc/mellanox/host/rshim_net.c
create mode 100644 drivers/soc/mellanox/host/rshim_pcie.c
create mode 100644 drivers/soc/mellanox/host/rshim_pcie_lf.c
create mode 100644 drivers/soc/mellanox/host/rshim_regs.h
create mode 100644 drivers/soc/mellanox/host/rshim_usb.c
create mode 100644 drivers/soc/mellanox/tmfifo.c
create mode 100644 drivers/soc/mellanox/tmfifo_regs.h
--
1.8.3.1
