[U-Boot] [PATCH v5] Tegra: T210: Add QSPI driver

[Jagan Teki]

On 6 November 2015 at 23:08, Tom Warren <TWarren at nvidia.com> wrote:
> Jagan,
>
>> -----Original Message-----
>> From: Jagan Teki [mailto:jteki at openedev.com]
>> Sent: Friday, November 06, 2015 9:40 AM
>> To: Tom Warren <TWarren at nvidia.com>
>> Cc: u-boot at lists.denx.de; Stephen Warren <swarren at nvidia.com>;
>> tomcwarren3959 at gmail.com
>> Subject: Re: [U-Boot] [PATCH v5] Tegra: T210: Add QSPI driver
>>
>> On 6 November 2015 at 22:01, Tom Warren <TWarren at nvidia.com> wrote:
>> > Jagan,
>> >
>> > Ping!
>> >
>> >> -----Original Message-----
>> >> From: Tom Warren
>> >> Sent: Thursday, October 29, 2015 12:33 PM
>> >> To: 'Jagan Teki' <jteki at openedev.com>
>> >> Cc: u-boot at lists.denx.de; Stephen Warren <swarren at nvidia.com>;
>> >> tomcwarren3959 at gmail.com; Yen Lin <yelin at nvidia.com>
>> >> Subject: RE: [U-Boot] [PATCH v5] Tegra: T210: Add QSPI driver
>> >>
>> >> Jagan,
>> >>
>> >> > -----Original Message-----
>> >> > From: Jagan Teki [mailto:jteki at openedev.com]
>> >> > Sent: Thursday, October 29, 2015 10:34 AM
>> >> > To: Tom Warren <TWarren at nvidia.com>
>> >> > Cc: u-boot at lists.denx.de; Stephen Warren <swarren at nvidia.com>;
>> >> > tomcwarren3959 at gmail.com
>> >> > Subject: Re: [U-Boot] [PATCH v5] Tegra: T210: Add QSPI driver
>> >> >
>> >> > On 28 October 2015 at 21:25, Tom Warren <TWarren at nvidia.com>
>> wrote:
>> >> > > Jagan,
>> >> > >
>> >> > >> -----Original Message-----
>> >> > >> From: Tom Warren
>> >> > >> Sent: Monday, October 26, 2015 1:56 PM
>> >> > >> To: u-boot at lists.denx.de
>> >> > >> Cc: Stephen Warren <swarren at nvidia.com>;
>> >> tomcwarren3959 at gmail.com;
>> >> > >> jteki at openedev.com; Yen Lin <yelin at nvidia.com>; Tom Warren
>> >> > >> <TWarren at nvidia.com>
>> >> > >> Subject: [PATCH v5] Tegra: T210: Add QSPI driver
>> >> > >>
>> >> > >> This is the normal Tegra SPI driver modified to work with the
>> >> > >> QSPI controller in Tegra210. It does not do 2x/4x transfers or
>> >> > >> any other QSPI
>> >> > protocol.
>> >> > >>
>> >> > >> Signed-off-by: Yen Lin <yelin at nvidia.com>
>> >> > >> Signed-off-by: Tom Warren <twarren at nvidia.com>
>> >> >
>> >> > Reviewed-by: Jagan Teki <jteki at openedev.com>
>> >> >
>> >> > >> ---
>> >> > >> Changes in v2:
>> >> > >> - Drop defconfig and pinmux files, this is a driver-only patch.
>> >> > >> - If/when pinmux tables have been updated for P2371/P2571,
>> >> > >> another
>> >> > >> - patch will be sent to enable the QSPI driver on those boards.
>> >> > >> Changes in v3:
>> >> > >> - removed status reg write/clear in claim_bus(), done in xfer()
>> >> > >> Changes in
>> >> > v4:
>> >> > >> - added timeout in wait for FIFO flush status in xfer()
>> >> > >> - used BIT and GENMASK macros throughout
>> >> > >> - minor changes in copyright message in driver and Kconfig help
>> >> > >> Changes in v5:
>> >> > >> - commented on reason for udelay before setting GO bit, as per Yen
>> Lin.
>> >> > >
>> >> > > Can you PTAL and see if this meets all your requests? Thanks.
>> >> >
>> >> > OK with this? Can you point the dts and config patch for this
>> >> > driver - I couldn't find it either.
>> >> The intent is to only upstream the driver. The DTS already contains
>> >> the QSPI node (see spi at 0,70410000), and the defconfig/pinmux-config.h
>> >> changes won't be merged since there's no T210 board (from Nvidia)
>> >> that has a SPI part on the QSPI controller currently. There is a
>> >> customer with their own board that needs this driver upstreamed so they
>> can pull it down into their custom U-Boot repo.
>> >> However, if you search the list for my original patch ('[PATCH]
>> >> Tegra210: add QSPI driver'), you'll see examples of the p2571
>> >> def_config/pinmux configs that can be used if someone does wish to pop a
>> SPI chip on their T210 board, etc.
>>
>> I'm little concern about stale driver without have any board to use, any
>> possibility that T210 will be in ML - because I have removed some in past as
>> there is no progress on the drivers as no board's been used for long time.
>
> There are downstream (customer and in-house dev) boards that use/will use this driver, hence the need to upstream it. It just happens to be true that no _current_ T210 boards have a SPI chip hanging off of the QSPI pins at this time.
>
> I'm not sure what 'T210 will be in ML' means, though.
>
> As to progress on the driver, it works fine as-is - I'm not sure what progress you are looking for - I'm certain there are a lot of drivers in U-Boot that have been written once and remained virtually untouched since then, and continue to work just fine.

OK, then take this via tegra repo.

>
>>
>> >>
>> >> So with that in mind, will you take this in to the SPI repo, or can I
>> >> take it in via the Tegra repo instead? I'm fine with either course.
>> >>
>> >> Tom
>> >> --
>> >> nvpublic
>> >>
>> >> >
>> >> > >
>> >> > > And do you want to take this in, or can I take it in via the Tegra repo?

thanks!
-- 
Jagan | openedev.