Re: [PATCH] ARM: dts: at91: sama5d2 Xplained: add QSPI0 + SPI NOR memory nodes

From: Ludovic Desroches
Date: Tue Dec 11 2018 - 09:50:13 EST


On Tue, Dec 11, 2018 at 03:35:45PM +0100, Alexandre Belloni wrote:
> On 11/12/2018 12:32:40+0000, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
> > Hi, Alexandre,
> >
> > On 12/10/2018 11:35 PM, Alexandre Belloni wrote:
> > > Hi,
> > >
> > > On 10/12/2018 17:15:29+0000, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
> > >> From: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxx>
> > >>
> > >> This patch configures the QSPI0 controller pin muxing and declares
> > >> a jedec,spi-nor memory.
> > >>
> > >> sama5d2 Xplained RevB and RevC use the Macronix MX25L25673G flash
> > >> memory which advertises a maximum frequency of 80MHz for Quad IO
> > >> Fast Read. Set the spi-max-frequency to 80MHz knowing that actually
> > >> the QSPI drver will set the SPI bus clock to 166MHz / 3 = 55.3MHz.
> > >>
> > >> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxx>
> > >> [tudor.ambarus@xxxxxxxxxxxxx:
> > >> - drop partitions,
> > >> - add spi-rx/tx-bus-width
> > >> - change spi-max-frequency to match the 80MHz limit advertised by
> > >> MX25L25673G for Quad IO Fast Read,
> > >> - reword commit message and subject.]
> > >> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
> > >> ---
> > >> arch/arm/boot/dts/at91-sama5d2_xplained.dts | 31 +++++++++++++++++++++++++++++
> > >> 1 file changed, 31 insertions(+)
> > >>
> > >> diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> > >> index 518e2b095ccf..171bc82cfbbf 100644
> > >> --- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> > >> +++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
> > >> @@ -108,6 +108,21 @@
> > >> };
> > >>
> > >> apb {
> > >> + qspi0: spi@f0020000 {
> > >> + pinctrl-names = "default";
> > >> + pinctrl-0 = <&pinctrl_qspi0_default>;
> > >> + /* status = "okay"; */ /* conflict with sdmmc1 */
> > >
> > > Isn't that conflicting then because I think the default is okay.
> > qspi0 is disabled in sama5d2.dtsi.
> >
>
> Ok, then maybe that comment is not necessary at all.

Usually we do it the other way around:
status = "disabled"; /* conflict with ... */

Regards

Ludovic