Re: [PATCH v3 00/27] memory: omap-gpmc: mtd: nand: Support GPMC NAND on non-OMAP platforms

[Tony Lindgren <tony@atomide.com>]

* Roger Quadros <rogerq@ti.com> [150930 04:04]:
> Tony,
> 
> On 18/09/15 17:53, Roger Quadros wrote:
> > Hi,
> > 
> > We do a couple of things in this series which result in
> > cleaner device tree implementation, faster perfomance and
> > multi-platform support. As an added bonus we get new GPI/Interrupt pins
> > for use in the system.
> > 
> > - Establish a custom interface between NAND and GPMC driver. This is
> > needed because all of the NAND registers sit in the GPMC register space.
> > Some bits like NAND IRQ are even shared with GPMC.
> > 
> > - Remove NAND IRQ handling from omap-gpmc driver, share the GPMC IRQ
> > with the omap2-nand driver and handle NAND IRQ events in the NAND driver.
> > This causes performance increase when using prefetch-irq mode.
> > 30% increase in read, 17% increase in write in prefetch-irq mode.
> > 
> > - Clean up device tree support so that omap-gpmc IP and the omap2 NAND
> > driver can be used on non-OMAP platforms. e.g. Keystone.
> > 
> > - Implement GPIOCHIP + IRQCHIP for the GPMC WAITPINS. SoCs can contain
> > 2 to 4 of these and most of them would be unused otherwise. It also
> > allows a cleaner implementation of NAND Ready pin status for the NAND driver.
> > 
> > - Implement GPIOlib based NAND ready pin checking for OMAP NAND driver.
> > 
> > This series is available at
> > git@github.com:rogerq/linux.git
> > in branch
> > for-v4.4/gpmc-v3

In general, very nice work :)

> I've verified this series with the following boards
> -dra7-evm
> -am437x-gp-evm
> -am335x-evm
> -beagleboard-c4
> 
> For legacy boot I've checked only on beagleboard-c4.

Great.

Does build and boot and use NAND work throughtout the series?
Otherwise we'll have hard time bisecting anything..

> Test procedure was to read an existing ubifs partition,
> create a new one and read it back.
> 
> Need you to Ack if it looks good.
> Do you mind taking it via omap-soc once MTD maintainers ack their relevant parts?

Sure. I'll try to do some testing on the series first too.

Can the dts changes be merged separtely? Otherwise we'll have
a dependency between dts branch and the GPMC/NAND changes.

Regards,

Tony