[PATCH][v2] powerpc/fsl-booke: Add T1040D4RDB/T1042D4RDB board support

[Priyanka Jain]

> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Friday, July 17, 2015 1:06 AM
> To: Jain Priyanka-B32167
> Cc: linuxppc-dev at lists.ozlabs.org
> Subject: Re: [PATCH][v2] powerpc/fsl-booke: Add T1040D4RDB/T1042D4RDB
> board support
> 
> On Thu, 2015-07-16 at 04:34 -0500, Jain Priyanka-B32167 wrote:
> >
> > -----Original Message-----
> > From: Wood Scott-B07421
> > Sent: Wednesday, July 15, 2015 11:17 PM
> > To: Jain Priyanka-B32167
> > Cc: linuxppc-dev at lists.ozlabs.org
> > Subject: Re: [PATCH][v2] powerpc/fsl-booke: Add
> T1040D4RDB/T1042D4RDB
> > board support
> >
> > On Wed, 2015-07-15 at 15:00 +0530, Priyanka Jain wrote:
> > > T1040D4RDB/T1042D4RDB are Freescale Reference Design Board which
> can
> > > support T1040/T1042 QorIQ Power Architecture™ processor respectively
> > >
> > > T1040D4RDB/T1042D4RDB board Overview
> > > -------------------------------------
> > > - SERDES Connections, 8 lanes supporting:
> > >         - PCI
> > >         - SGMII
> > >         - SATA 2.0
> > >         - QSGMII(only for T1040D4RDB)
> > >     - DDR Controller
> > >         - Supports rates of up to 1600 MHz data-rate
> > >         - Supports one DDR4 UDIMM
> > >     -IFC/Local Bus
> > >         - NAND flash: 1GB 8-bit NAND flash
> > >         - NOR: 128MB 16-bit NOR Flash
> > >     - Ethernet
> > >         - Two on-board RGMII 10/100/1G ethernet ports.
> > >         - PHY #0 remains powered up during deep-sleep
> > >     - CPLD
> > >     - Clocks
> > >         - System and DDR clock (SYSCLK, “DDRCLK”)
> > >         - SERDES clocks
> > >     - Power Supplies
> > >     - USB
> > >         - Supports two USB 2.0 ports with integrated PHYs
> > >         - Two type A ports with   5V at 1.5Aperport.
> > >     - SDHC
> > >         - SDHC/SDXC connector
> > >     - SPI
> > >         - On-board 64MB SPI flash
> > >     - I2C
> > >         - Devices connected: EEPROM, thermal monitor, VID controller
> > >     - Other IO
> > >         - Two Serial ports
> > >         - ProfiBus port
> > >
> > >     Add support for T1040/T1042D4RDB board:
> > >     -add device tree
> > >     -Add entry in corenet_generic.c
> > >
> > > Signed-off-by: Priyanka Jain <Priyanka.Jain at freescale.com>
> > > ---
> > >  Changes for v2:
> > >       Incorporated Scott's comments on device tree
> >
> > You didn't respond to the comments on the CPLD node.
> > [Priyanka]
> > T1042D4RDB,  T1040D4RDB are derivatives of same board , CPLD is same
> > for both.
> > So, I have moved below node having compatible and reg field together
> > in t104xd4rdb.dtsi.
> > Is this fine?
> >               cpld at 3,0 {
> >                       compatible = "fsl,t1040d4rdb-cpld";
> >                       reg = <3 0 0x300>;
> >               };
> 
> If the CPLD image is exactly the same on both, this is fine.
> 
> > > +                i2c at 118100{
> > > +                      mux at 77{
> > > +                             compatible = "nxp,pca9546";
> > > +                             reg = <0x77>;
> > > +                             #address-cells = <1>;
> > > +                             #size-cells = <0>;
> > > +                     };
> > > +             };
> >
> > A mux with no nodes under it (and yet it has #address-cells/#size-cells)?
> > What is it multiplexing?
> > [Priyanka]: PCA9546 is i2c mux device , to which other i2c devices
> > (up-to 8
> > ) can be further connected on output channels On T104xD4RDB,  channel
> > 0, 1, 3 line are connected to PEX device, Channel 2 to hdmi interface
> > (initialization is done in u-boot only), other channels are grounded.
> > So, as such Linux is not using the second level I2C devices connected
> > on this MUX device. So, I have not shown next level hierarchy.
> > Should I replace 'mux' with some other name? . Please suggest.
> 
> The device tree describes the hardware, not just what Linux uses... but what
> I don't understand is why you describe the mux at all if you're not going to
> describe what goes underneath it.
> 
[Jain Priyanka-B32167] : Is below looks OK?
i2c at 118100{
 +                      i2c at 77{
 +                             compatible = "nxp,pca9546";
 +                             reg = <0x77>;
 +                             #address-cells = <1>;
 +                             #size-cells = <0>;
 +                     };
 +             };
> -Scott