Re: [PATCH] arm64: dts: imx8mp: Add dsp node

From: Daniel Baluta
Date: Fri Jul 16 2021 - 08:48:16 EST


On Fri, Jul 16, 2021 at 5:05 AM Peng Fan <peng.fan@xxxxxxx> wrote:
>
> Hi Daniel
>
> > Subject: [PATCH] arm64: dts: imx8mp: Add dsp node
> >
> > From: Daniel Baluta <daniel.baluta@xxxxxxx>
> >
> > i.MX8 MPlus SoC integrates Cadence HIFI4 DSP. This core runs either a custom
> > firmware or the open source SOF firmware [1]
> >
> > DSP device is handled by SOF OF driver found in sound/soc/sof/sof-of-dev.c
> >
> > Notice that the DSP node makes use of:
> > - dsp_reserved, a reserved memory region for various Audio
> > resources (e.g firmware loading, audio buffers, etc).
> > - Messaging Unit (mu2) for passing notifications betweem ARM
> > core and DSP.
> >
> > [1] https://thesofproject.github.io/latest/platforms/index.html
> > Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
> > ---
> > arch/arm64/boot/dts/freescale/imx8mp.dtsi | 28
> > +++++++++++++++++++++++
> > 1 file changed, 28 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > index 9f7c7f587d38..264ba540f363 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> > @@ -135,6 +135,17 @@ clk_ext4: clock-ext4 {
> > clock-output-names = "clk_ext4";
> > };
> >
> > + reserved-memory {
> > + #address-cells = <2>;
> > + #size-cells = <2>;
> > + ranges;
> > +
> > + dsp_reserved: dsp@92400000 {
> > + reg = <0 0x92400000 0 0x2000000>;
> > + no-map;
> > + };
> > + };
> > +
> > pmu {
> > compatible = "arm,cortex-a53-pmu";
> > interrupts = <GIC_PPI 7
> > @@ -698,6 +709,13 @@ mu: mailbox@30aa0000 {
> > #mbox-cells = <2>;
> > };
> >
> > + mu2: mailbox@30e60000 {
> > + compatible = "fsl,imx8mp-mu", "fsl,imx6sx-mu";
> > + reg = <0x30e60000 0x10000>;
> > + interrupts = <GIC_SPI 136 IRQ_TYPE_LEVEL_HIGH>;
> > + #mbox-cells = <2>;
>
> I think better mark this node as disabled. If its clock not enabled,
> kernel may hang.

Good point. Fixed in v2.