Hi Jagan,
-----Original Message----- From: Jagan Teki [mailto:jagannadh.teki@gmail.com] Sent: Wednesday, November 01, 2017 2:54 PM To: Siva Durga Prasad Paladugu sivadur@xilinx.com Cc: u-boot@lists.denx.de; Liam Beguin liambeguin@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@xilinx.com wrote:
Hi Jagan,
-----Original Message----- From: Jagan Teki [mailto:jagannadh.teki@gmail.com] Sent: Tuesday, October 31, 2017 3:01 PM To: Siva Durga Prasad Paladugu sivadur@xilinx.com Cc: u-boot@lists.denx.de; Liam Beguin liambeguin@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@xilinx.com wrote:
Hi Jagan,
-----Original Message----- From: Jagan Teki [mailto:jagannadh.teki@gmail.com] Sent: Tuesday, October 31, 2017 2:40 PM To: Siva Durga Prasad Paladugu sivadur@xilinx.com Cc: u-boot@lists.denx.de; Liam Beguin liambeguin@gmail.com;
Siva
Durga Prasad Paladugu sivadur@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@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.
Thanks, Siva.
Hope it clear.
thanks!
Jagan Teki Free Software Engineer | www.openedev.com U-Boot, Linux | Upstream Maintainer Hyderabad, India.