[U-Boot] [PATCH v4 00/21] sf: Tunning spi-flash layer
Jagan Teki
jteki at openedev.com
Fri Oct 30 21:33:45 CET 2015
On 31 October 2015 at 02:00, Marek Vasut <marex at denx.de> wrote:
> On Friday, October 30, 2015 at 09:02:15 PM, Jagan Teki wrote:
>> Hi Simon,
>>
>> On 30 October 2015 at 04:55, Simon Glass <sjg at chromium.org> wrote:
>> > Hi Jagan,
>> >
>> > On 28 October 2015 at 13:08, Jagan Teki <jteki at openedev.com> wrote:
>> >> Hi Simon,
>> >>
>> >> On 29 October 2015 at 00:17, Simon Glass <sjg at chromium.org> wrote:
>> >> > Hi Jagan,
>> >> >
>> >> > On 19 October 2015 at 03:28, Jagan Teki <jteki at openedev.com> wrote:
>> >> >> Hi Simon,
>> >> >>
>> >> >> On 19 October 2015 at 01:57, Simon Glass <sjg at chromium.org> wrote:
>> >> >>> Hi Jagan,
>> >> >>>
>> >> >>> On 12 October 2015 at 09:00, Jagan Teki <jteki at openedev.com> wrote:
>> >> >>>> Previous version link:
>> >> >>>> http://permalink.gmane.org/gmane.comp.boot-loaders.u-boot/233262
>> >> >>>>
>> >> >>>> spi-flash layer need to tune a lot for better code handling and
>> >> >>>> to sync with Linux spi-nor. So below areas got updated in this
>> >> >>>> series. - BAR handling
>> >> >>>> - spi_flash_cmd_wait_ready updates.
>> >> >>>> - Separate core spi-flash handling and spi-flash interface
>> >> >>>>
>> >> >>>> (interface between spi drivers vs spi-flash layer)
>> >> >>>>
>> >> >>>> Currently I'm working on spi-nor framework for u-boot which
>> >> >>>> is slighly same as Linux spi-nor core with addition of
>> >> >>>> u-boot driver model to it.
>> >> >>>>
>> >> >>>> This series will be starting point to add spi-nor functionalities.
>> >> >>>>
>> >> >>>> TODO:
>> >> >>>> - MTD core addition to spi-flash layer.
>> >> >>>> - spi-nor core addition.
>> >> >>>>
>> >> >>>> Code sizes:
>> >> >>>> After:
>> >> >>>>
>> >> >>>> dm:
>> >> >>>> text data bss dec hex filename
>> >> >>>>
>> >> >>>> 354820 12016 221112 587948 8f8ac u-boot
>> >> >>>>
>> >> >>>> non-dm
>> >> >>>>
>> >> >>>> text data bss dec hex filename
>> >> >>>>
>> >> >>>> 354317 11876 221124 587317 8f635 u-boot
>> >> >>>>
>> >> >>>> Before:
>> >> >>>> dm
>> >> >>>>
>> >> >>>> text data bss dec hex filename
>> >> >>>>
>> >> >>>> 354878 12016 221096 587990 8f8d6 u-boot
>> >> >>>>
>> >> >>>> non-dm
>> >> >>>>
>> >> >>>> text data bss dec hex filename
>> >> >>>>
>> >> >>>> 354447 11876 221124 587447 8f6b7 u-boot
>> >> >>>
>> >> >>> I don't think you should be adding new features to the
>> >> >>> non-driver-model SPI flash code. We are supposed to be migrating
>> >> >>> everything to driver model, so it would be better to move your
>> >> >>> boards over, and then work to deprecate and remove the old code.
>> >> >>> Adding new features to it sends the wrong message.
>> >> >>
>> >> >> spi-flash core code doesn't require to add driver model, and cmd_sf
>> >> >> to spi-flash code is already supporting driver model.
>> >> >>
>> >> >> OK, let me explain in-detail.
>> >> >>
>> >> >> Code in sf_probe.c supports both dm and non dm-spi-flash and flash
>> >> >> initialization code using
>> >> >> spi_flash_validate_params. sf.c acts as interface between spi drivers
>> >> >> vs spi-flash code.
>> >> >> So the spi-flash initialization code(part of sf_probe) and code in
>> >> >> sf_ops are commonly categorized as spi-flash core code and this will
>> >> >> not require driver model, so-that the dm drivers will simply use this
>> >> >> common code for spi-flash core functionality.
>> >> >>
>> >> >> This patch series will separate all the necessary existing code into
>> >> >> core and spi-flash vs spi drivers interface code. So at ends
>> >> >> - sf_probe is simply the copy of sf.c and dm and non-dm spi-flash
>> >> >> code so this will acts a spi-flash vs spi drivers interface. (which
>> >> >> has dm and non-dm as same as before)
>> >> >> - sf_ops is core spi-flash functionality.
>> >> >>
>> >> >> On top of this I'm adding actual spi-nor core code, where sf_ops.c
>> >> >> will become spi-nor.c and sf_probe.c will become spi-nor-flash.c.
>> >> >> - spi-nor.c: Core SPI NOR
>> >> >> - spi-nor-flash: spi drivers vs spi-nor interface (which has dm and
>> >> >> non-dm as same as before)
>> >> >>
>> >> >> The reason for adding this spi-nor is to move flash code from
>> >> >> spi-drivers, example fsl_qspi and at the end this fsl_qspi will move
>> >> >> from spi drivers to spi-nor that will be in driver model.
>> >> >>
>> >> >> I'm simply adding new core functionality with adding new drivers as
>> >> >> dm-driven, I don't think this will not effect/change the driver model
>> >> >> growth.
>> >> >>
>> >> >> View of spi-nor framework:
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> cmd_sf
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> spi_flash
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> MTD Core
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> sf-uclass
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> SPI-NOR
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> spi-nor-flash drivers/mtd/spi/*
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> spi-uclass
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> drivers/spi/*
>> >> >>
>> >> >> -----------------------------------------------------
>> >> >>
>> >> >> drivers/mtd/spi/spi-nor.c: spi-nor core (not require to add dm)
>> >> >> drivers/mtd/spi/spi-flash-nor.c: spi-nor to spi drivers interface
>> >> >> (dm-driven) drivers/mtd/spi/fsl-quadspi.c: spi-nor controller driver
>> >> >> (dm-driven)
>> >> >>
>> >> >> Please let me know for any more comments.
>> >> >
>> >> > Perhaps another way of asking this is, what is the plan to remove the
>> >> > non-DM code from SF or at least stop adding new features to it.
>> >>
>> >> Sorry I didn't understand "remove non-dm code" or either I missed
>> >> something here.
>> >>
>> >> The plan is not to remove any code intentionally it's about following
>> >> feature additions
>> >> 1) Tuning up spi-flash framework: Separating Core spi-flash code and
>> >> interface code between spi-flash vs spi drivers
>> >> 2) Adding MTD core support to spi-flash core (no spi_flash ops -
>> >> mtd_ops will use)
>> >> 3) Introduce spi-nor core (spi-flash core becomes spi-nor) and new
>> >> spi-nor controller drivers are part of this like fsl_qspi or etc.
>> >> spi-nor controllers and interface code between spi-flash vs
>> >> spi-drivers become UCLASS_SPI_NOR
>> >>
>> >> Agenda is to add SPI-NOR framework(almost similar to Linux) with
>> >> driver model(as UCLASS_SPI_NOR)
>> >>
>> >> ------------------------------------------------------------------------
>> >> -----------------------
>> >>
>> >> cmd_spi cmd_sf
>> >>
>> >> -------|----------------------------------------------------------------
>> >> ------------------------
>> >>
>> >> | spi_flash
>> >>
>> >> -------|----------------------------------------------------------------
>> >> ------------------------
>> >>
>> >> | MTD Core
>> >>
>> >> -------|----------------------------------------------------------------
>> >> ------------------------
>> >>
>> >> | spi-nor-uclass
>> >>
>> >> -------|----------------------------------------------------------------
>> >> ------------------------
>> >>
>> >> | SPI-NOR Core
>> >> | (spi-nor.c)
>> >>
>> >> -------|----------------------------------------------------------------
>> >> -------------------------
>> >>
>> >> | |=========spi-nor-flash
>> >>
>> >> drivers/mtd/spi/fsl_qspi
>> >>
>> >> | | (m25p80.c)
>> >>
>> >> (fsl-quadspi.c)
>> >>
>> >> --------|-------V-------------------------------------------------------
>> >> ----------------------------
>> >>
>> >> spi-uclass
>> >>
>> >> ------------------------------------------------------------------------
>> >> --------------------------
>> >>
>> >> drivers/spi/*
>> >>
>> >> -----------------------------------------------------
>> >>
>> >> Let me know for any more comments?
>> >
>> > This is quite a big topic. Also you are the maintainer, not me. So I
>> > don't want to interfere. It's just that I am conscious that my SPI
>> > flash conversion was incomplete, in that:
>> >
>> > - it still provides the old API (and we need to keep this until every
>> > board migrates)
>> > - it still uses struct spi_flash as a parameter, when it should really
>> > use struct udevice
>> > - the concept of chip select number and bus number are still present,
>> > but in the end these should just be devices
>> >
>> > So I'm keen to keep moving things in the direction of 'fully migrated'.
>> >
>> > Adding a new feature like SPI nor seems like a good oppty to encourage
>> > people to move over to driver model - .e.g if the new feature is only
>> > available with driver model.
>>
>> Just park this spi-nor stuff, once I send all patches will discuss more.
>>
>> This series is for code re-factorization like separating spi-flash
>> core functionality vs spi-driver interface from spi-flash core. Did
>> you find any wrong on this?
>
> Why don't we converge toward Linux's spi-nor stack instead ?
Yes I'm trying for the same model with dm-driven (UCLASS_SPI_NOR)
thanks!
--
Jagan | openedev.
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