Re: [PATCH v1 3/3] arm64: dts: add Hi6220 mailbox node

[Leo Yan <leo.yan@linaro.org>]

Hi Mark,

On Sat, Aug 22, 2015 at 09:30:50PM +0800, Leo Yan wrote:
> On Fri, Aug 21, 2015 at 07:40:59PM +0100, Mark Rutland wrote:
> > On Wed, Aug 19, 2015 at 10:37:35AM +0100, Leo Yan wrote:
> > > On Hi6220, below memory regions in DDR have specific purpose:
> > > 
> > >   0x05e0,0000 - 0x05ef,ffff: For MCU firmware using at runtime;
> > >   0x0740,f000 - 0x0740,ffff: For MCU firmware's section;
> > >   0x06df,f000 - 0x06df,ffff: For mailbox message data.
> > > 
> > > This patch reserves these memory regions and add device node for
> > > mailbox in dts.
> > > 
> > > Signed-off-by: Leo Yan <leo.yan@linaro.org>
> > > ---
> > >  arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts | 20 +++++++++++++++++---
> > >  arch/arm64/boot/dts/hisilicon/hi6220.dtsi      |  8 ++++++++
> > >  2 files changed, 25 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> > > index e36a539..d5470d3 100644
> > > --- a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> > > +++ b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
> > > @@ -7,9 +7,6 @@
> > >  
> > >  /dts-v1/;
> > >  
> > > -/*Reserved 1MB memory for MCU*/
> > > -/memreserve/ 0x05e00000 0x00100000;
> > > -
> > >  #include "hi6220.dtsi"
> > >  
> > >  / {
> > > @@ -28,4 +25,21 @@
> > >  		device_type = "memory";
> > >  		reg = <0x0 0x0 0x0 0x40000000>;
> > >  	};
> > > +
> > > +	reserved-memory {
> > > +		#address-cells = <2>;
> > > +		#size-cells = <2>;
> > > +		ranges;
> > > +
> > > +		mcu-buf@05e00000 {
> > > +			no-map;
> > > +			reg = <0x0 0x05e00000 0x0 0x00100000>,	/* MCU firmware buffer */
> > > +			      <0x0 0x0740f000 0x0 0x00001000>;	/* MCU firmware section */
> > > +		};
> > > +
> > > +		mbox-buf@06dff000 {
> > > +			no-map;
> > > +			reg = <0x0 0x06dff000 0x0 0x00001000>;	/* Mailbox message buf */
> > > +		};
> > > +	};
> > 
> > As far as I can see, it would be simpler to simply carve these out of the
> > memory node.
> 
> Will modify for MCU firmware buffer and section.
> 
> > I don't see why you need reserved-memory here, given you're not referring to
> > these regions by phandle anyway.
> 
> mbox-buf is used by below mailbox's node, but the start address has
> been truncated with 4KB alignment; so should keep it, right?

I think i got your point, all these nodes can be removed and just use
memory node to carve them out; but currently i saw the memory node
cannot be passed correctly from UEFI to kernel, we will check for
this. So will follow your suggestion if without any unknown reason.

Thanks,
Leo Yan

> > >  };
> > > diff --git a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> > > index 3f03380..9ff25bc 100644
> > > --- a/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> > > +++ b/arch/arm64/boot/dts/hisilicon/hi6220.dtsi
> > > @@ -167,5 +167,13 @@
> > >  			clocks = <&ao_ctrl 36>, <&ao_ctrl 36>;
> > >  			clock-names = "uartclk", "apb_pclk";
> > >  		};
> > > +
> > > +		mailbox: mailbox@f7510000 {
> > > +			#mbox-cells = <1>;
> > > +			compatible = "hisilicon,hi6220-mbox";
> > > +			reg = <0x0 0xf7510000 0x0 0x1000>, /* IPC_S */
> > > +			      <0x0 0x06dff800 0x0 0x0800>; /* Mailbox buffer */
> > > +			interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>;
> > > +		};
> > >  	};
> > >  };
> > > -- 
> > > 1.9.1
> > >