[U-Boot] [UBOOT PATCH 1/2] spi: zynqmp_qspi: Add support for ZynqMP qspi driver

[Siva Durga Prasad Paladugu]

Hi jagan,

> -----Original Message-----
> From: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> Sent: Thursday, December 07, 2017 10:56 AM
> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
> Cc: u-boot at lists.denx.de; Liam Beguin <liambeguin at gmail.com>
> Subject: Re: [UBOOT PATCH 1/2] spi: zynqmp_qspi: Add support for
> ZynqMP qspi driver
> 
> On Thu, Nov 23, 2017 at 1:00 PM, Siva Durga Prasad Paladugu
> <sivadur at xilinx.com> wrote:
> > Hi Jagan,
> >
> >> -----Original Message-----
> >> From: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> >> Sent: Wednesday, November 01, 2017 2:54 PM
> >> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
> >> Cc: u-boot at lists.denx.de; Liam Beguin <liambeguin at gmail.com>
> >> Subject: Re: [UBOOT PATCH 1/2] spi: zynqmp_qspi: Add support for
> >> ZynqMP qspi driver
> >>
> >> On Tue, Oct 31, 2017 at 6:33 PM, Siva Durga Prasad Paladugu
> >> <sivadur at xilinx.com> wrote:
> >> > Hi Jagan,
> >> >
> >> >> -----Original Message-----
> >> >> From: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> >> >> Sent: Tuesday, October 31, 2017 3:01 PM
> >> >> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
> >> >> Cc: u-boot at lists.denx.de; Liam Beguin <liambeguin at gmail.com>
> >> >> Subject: Re: [UBOOT PATCH 1/2] spi: zynqmp_qspi: Add support for
> >> >> ZynqMP qspi driver
> >> >>
> >> >> On Tue, Oct 31, 2017 at 2:50 PM, Siva Durga Prasad Paladugu
> >> >> <sivadur at xilinx.com> wrote:
> >> >> > Hi Jagan,
> >> >> >
> >> >> >> -----Original Message-----
> >> >> >> From: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> >> >> >> Sent: Tuesday, October 31, 2017 2:40 PM
> >> >> >> To: Siva Durga Prasad Paladugu <sivadur at xilinx.com>
> >> >> >> Cc: u-boot at lists.denx.de; Liam Beguin <liambeguin at gmail.com>;
> >> Siva
> >> >> >> Durga Prasad Paladugu <sivadur at xilinx.com>
> >> >> >> Subject: Re: [UBOOT PATCH 1/2] spi: zynqmp_qspi: Add support
> >> >> >> for ZynqMP qspi driver
> >> >> >>
> >> >> >> On Tue, Oct 24, 2017 at 3:33 PM, Siva Durga Prasad Paladugu
> >> >> >> <siva.durga.paladugu at xilinx.com> wrote:
> >> >> >> > This patch adds qspi driver support for ZynqMP SoC. This
> >> >> >> > driver is responsible for communicating with qspi flash devices.
> >> >> >>
> >> >> >> Legacy question, what is your approach for dual memory setup?
> >> >> >> Did you write another flash driver?
> >> >> > No
> >> >> >
> >> >> >>
> >> >> >> I see this driver use dual flash slave 'option' which doesn't
> >> >> >> live on spi side anymore. better to have a discussion on
> >> >> >> approach and will
> >> >> review further.
> >> >> >
> >> >> > I can see that spi_flash.c(driver/mtd/spi/spi_flash.c) has the
> >> >> > option for
> >> >> dual flash under CONFIG_SF_DUAL_FLASH.
> >> >> > I thought of using the same. Isn't it takes care of dual flash case?
> >> >> > Please let me know if you any further thoughts on how it has to
> >> >> > be
> >> >> handled.
> >> >>
> >> >> Dual flash case should take for generic spi drivers, if you
> >> >> strictly want your controller to handle flash device rather
> >> >> !flashes then we need to write the driver at flash side. ie why I asked
> as first question.
> >> >
> >> > Does this mean that drivers that are present in drivers/spi/ should
> >> > work for both flashes and !flashes. And the drivers that only
> >> > targets flash devices should be in different place and doesn’t use
> >> > Dual flash
> >> functionality under CONFIG_SF_DUAL_FLASH? Or it can still use this.
> >>
> >> Sorry, you understand it reverse or may be I'm not clear.
> >>
> >> drivers at drivers/spi can handle only generic slaves which includes
> >> spi-flash and some spi-flash(spi-nor) controllers which only deals
> >> with spi-flash slaves which can be part of drivers/mtd/spi. Since
> >> your driver is categorized as spi-nor controller(in above notes from
> >> you) it's better to write driver at drivers/mtd/spi side.
> >
> > No, the controller is meant to handle other slaves as well along with spi-
> nor.
> > Also for now, we are targeting single spi flash. So, keeping the
> > driver here should just be fine. Please let me know if you need any further
> info.
> 
> remember if driver sits here, then we can't extent your controller specific
> functions.
Yes, that’s fine, we are not targeting to have controller specific features. When we do
We will move it to new place as you suggest.
> 
> And rebase your patches and set it again.

I will rebase on top of latest master and will send v2.

Thanks,
Siva