Thanks Arnd for the comments! Please see the response inline. - Liming > -----Original Message----- > From: arndbergmann@xxxxxxxxx [mailto:arndbergmann@xxxxxxxxx] On > Behalf Of Arnd Bergmann > Sent: Thursday, October 25, 2018 11:33 AM > To: Liming Sun <lsun@xxxxxxxxxxxx> > Cc: Olof Johansson <olof@xxxxxxxxx>; David Woods > <dwoods@xxxxxxxxxxxx>; Robin Murphy <robin.murphy@xxxxxxx>; arm- > soc <arm@xxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH v4 3/4] dt-bindings: soc: Add TmFifo binding for Mellanox > BlueField SoC > > On 10/24/18, Liming Sun <lsun@xxxxxxxxxxxx> wrote: > > Add devicetree bindings for the TmFifo which is found on Mellanox > > BlueField SoCs. > > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > Reviewed-by: David Woods <dwoods@xxxxxxxxxxxx> > > Signed-off-by: Liming Sun <lsun@xxxxxxxxxxxx> > > --- > > .../devicetree/bindings/soc/mellanox/tmfifo.txt | 23 > > ++++++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > create mode 100644 > > Documentation/devicetree/bindings/soc/mellanox/tmfifo.txt > > > > diff --git a/Documentation/devicetree/bindings/soc/mellanox/tmfifo.txt > > b/Documentation/devicetree/bindings/soc/mellanox/tmfifo.txt > > new file mode 100644 > > index 0000000..8a13fa6 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/soc/mellanox/tmfifo.txt > > @@ -0,0 +1,23 @@ > > +* Mellanox BlueField SoC TmFifo > > + > > +BlueField TmFifo provides a shared FIFO between the target and the > > +external host machine, which can be accessed by external host via > > +USB or PCIe. In the current tmfifo driver, this FIFO has been demuxed > > +to implement virtual console and network interface based on the virtio > > +framework. > > + > > +Required properties: > > + > > +- compatible: Should be "mellanox,bf-tmfifo" > > +- reg: Physical base address and length of Rx/Tx block > > +- interrupts: The interrupt number of Rx low water mark, Rx high water > > mark > > + Tx low water mark, Tx high water mark respectively. > > > This sounds like it might fit into the mailbox subsystem, and perhaps > it should use the mailbox DT bindings. Have you had a look at that? This commit of dt-bindings is mainly to solve the warning of checkpatch.pl. Like the response to patch 2/4, ACPI is actually used now instead of device tree. The TMFIFO definition in the ACPI DSDT table would be something like below. // RShim TMFIFO Device(RSH0) { Name(_HID, "MLNXBF01") Name(_UID, Zero) Name(_CCA, 1) Name(_CRS, ResourceTemplate() { Memory32Fixed(ReadWrite, 0x00800a20, 0x00000018) Memory32Fixed(ReadWrite, 0x00800a40, 0x00000018) Interrupt(ResourceConsumer, Edge, ActiveHigh, Exclusive) { BF1_RSH0_TM_HTT_LWM_INT, BF1_RSH0_TM_HTT_HWM_INT, BF1_RSH0_TM_TTH_LWM_INT, BF1_RSH0_TM_TTH_HWM_INT } }) } Any suggestion how it should be added into Linux Documentation, or maybe I should just remove this commit from this patch series? As for the sub-component of this driver, the "soc" might be better fit than the mailbox for some reasons. It's a communication between extern machines and the SoC via USB / PCIe, like pushing boot stream, console and network mgmt. Some of the features, like pushing boot stream, doesn't communicate with the ARM core. The boot stream is pushed to the SoC HW logic directly. I'll add the host-side virtio-based driver in patch v5. > > Arnd
