Re: [PATCH 2/3] arm64: dts: imx8mn-tqma8mqnl: restrict clock for SPI-NOR flash

[Alexander Stein]

Am Dienstag, 6. Oktober 2026, 15:46:50 Mitteleuropäische Sommerzeit schrieb Frank Li:
> On Tue, Oct 06, 2026 at 03:25:10PM +0200, Alexander Stein wrote:
> > From: Markus Niebel <Markus.Niebel@xxxxxxxxxxxxxxx>
> >
> > The FlexSPI controller uses quad SPI with internal clock recovery.
> > The clock is therefore restricted to 66.666666 MHz according to
> > data sheet.
> 
> Which datasheet? I suppose NOR flash datasheet, can you provide link
> here.

The i.MX8M Nano data sheet Rev 5 09/2022 section 3.9.1.1 "SDR mode with
FlexSPIn_MCR0[RXCLKSRC] = 0x0, 0x1, 0x2" Table 55. "FlexSPI input timing
in SDR mode where FlexSPIn_MCR0[RXCLKSRC] = 0x0" lists 66 Mhz maximum for
"Frequency of operation".

Best regards
Alexander

> Frank
> 
> >
> > Signed-off-by: Markus Niebel <Markus.Niebel@xxxxxxxxxxxxxxx>
> > Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> > ---
> >  arch/arm64/boot/dts/freescale/imx8mn-tqma8mqnl.dtsi | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mn-tqma8mqnl.dtsi b/arch/arm64/boot/dts/freescale/imx8mn-tqma8mqnl.dtsi
> > index 48a687926aa1b..c88d83243097f 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mn-tqma8mqnl.dtsi
> > +++ b/arch/arm64/boot/dts/freescale/imx8mn-tqma8mqnl.dtsi
> > @@ -63,7 +63,7 @@ &flexspi {
> >  	flash0: flash@0 {
> >  		compatible = "jedec,spi-nor";
> >  		reg = <0>;
> > -		spi-max-frequency = <84000000>;
> > +		spi-max-frequency = <66666666>;
> >  		spi-tx-bus-width = <1>;
> >  		spi-rx-bus-width = <4>;
> >  		vcc-supply = <&buck5_reg>;
> > --
> > 2.55.0
> >
> >
> 


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