[U-Boot] [PATCH] mtd: nand: mxs: Add support for multiple NAND chips

[Scott Wood <scottwood@freescale.com>]

On Sat, 2014-12-06 at 14:07 +0100, Marek Vasut wrote:
> On Tuesday, December 02, 2014 at 02:26:14 PM, Stefan Roese wrote:
> > This patch adds support for multiple NAND chips connected to the
> > i.MX6. Linux already supports this configuration. So lets port
> > the missing features to the U-Boot driver to support more than
> > one NAND chip here as well.
> > 
> > The necessary changes in detail are:
> > 
> > - Only use DMA channel 0 for all NAND chips:
> >   Linux: a7c12d01 (mtd: gpmi: use DMA channel 0 for all the
> >                    nand chips)
> >          d159d8b7 (mtd: gpmi: decouple the chip select from
> >                    the DMA channel)
> > - On i.MX6 only use ready/busy pin for CS0:
> >   Linux: 7caa4fd2 (mtd: gpmi: imx6: fix the wrong method for
> >                    checking ready/busy)
> > 
> > To enable this feature the board needs to configure
> > CONFIG_SYS_NAND_MAX_CHIPS to 2 (or more).
> > 
> > With these changes I'm able to detect and acces 2 NAND chips:
> > 
> > => nand device
> > 
> > Device 0: 2x nand0, sector size 128 KiB
> >   Page size      2048 b
> >   OOB size         64 b
> >   Erase size   131072 b
> 
> Shouldn't you see "Device 0" and "Device 1" ?

The "2x" indicates that there are two identical chips being treated as a
single device (chip->numchips).

-Scott