From: Piotr Sroka <piotrs@cadence.com> To: Miquel Raynal <miquel.raynal@bootlin.com> Cc: <linux-kernel@vger.kernel.org>, Boris Brezillon <bbrezillon@kernel.org>, Richard Weinberger <richard@nod.at>, David Woodhouse <dwmw2@infradead.org>, Brian Norris <computersforpeace@gmail.com>, Marek Vasut <marek.vasut@gmail.com>, Paul Burton <paul.burton@mips.com>, "Geert Uytterhoeven" <geert@linux-m68k.org>, Arnd Bergmann <arnd@arndb.de>, "Marcel Ziswiler" <marcel.ziswiler@toradex.com>, Dmitry Osipenko <digetx@gmail.com>, Stefan Agner <stefan@agner.ch>, <linux-mtd@lists.infradead.org> Subject: Re: [PATCH v2 1/2] mtd: nand: Add Cadence NAND controller driver Date: Mon, 1 Jul 2019 11:21:36 +0100 [thread overview] Message-ID: <20190701102135.GA20033@global.cadence.com> (raw) In-Reply-To: <20190701120454.6c8ac48e@xps13> The 07/01/2019 12:04, Miquel Raynal wrote: >EXTERNAL MAIL > > >Hi Piotr, > >Piotr Sroka <piotrs@cadence.com> wrote on Mon, 1 Jul 2019 10:51:45 >+0100: > > >[...] >> >> >> > >> >> >> >This driver is way too massive, I am pretty sure it can shrink a >> >> >> >little bit more. >> >> >> >[...] >> >> >> > >> >> >> I will try to make it shorer but it will be difucult to achive. It is because - there are a lot of calculation needed for PHY - ECC are interleaved with data (like on marvell-nand or gpmi-nand). >> >> >> Therefore: + RAW mode is complicated + protecting BBM increases number of lines of source code >> >> >> - need to support two DMA engines internal and external (slave) We will see on next patch version what is the result. That page layout looks: >> >> > >> >> >Maybe you don't need to support both internal and external DMA? >> >> > >> >> >I am pretty sure there are rooms for size reduction. >> >> >> >> I describe how it works in general and maybe you help me chose better solution. >> >> >> >> HW controller can work in 3 modes. PIO - can work in master or slave DMA >> >> CDMA - needs Master DMA for accessing command descriptors. >> >> Generic mode - can use only Slave DMA. >> >> >> >> Generic mode is neccessery to implement functions other than page >> >> program, page read, block erase. So it is essential. I cannot avoid >> >> to use Slave DMA. >> > >> >This deserves a nice comment at the top. >> Ok I will add the modes description to cover letter. > > >Not only to the cover letter: People read the code. Interested people >might also read the commit log which is quite easy to find. The cover >letter however will just disappear in the history of the Internet. I >would rather prefer you explain how the IP works at the top of the >driver. So I will add the modes description to both cover letter and at the top of the driver. > > >Thanks, >Miquèl Thanks, Piotr
WARNING: multiple messages have this Message-ID (diff)
From: Piotr Sroka <piotrs@cadence.com> To: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Arnd Bergmann <arnd@arndb.de>, Boris Brezillon <bbrezillon@kernel.org>, Marcel Ziswiler <marcel.ziswiler@toradex.com>, Richard Weinberger <richard@nod.at>, linux-kernel@vger.kernel.org, Stefan Agner <stefan@agner.ch>, Marek Vasut <marek.vasut@gmail.com>, Paul Burton <paul.burton@mips.com>, Geert Uytterhoeven <geert@linux-m68k.org>, linux-mtd@lists.infradead.org, Dmitry Osipenko <digetx@gmail.com>, Brian Norris <computersforpeace@gmail.com>, David Woodhouse <dwmw2@infradead.org> Subject: Re: [PATCH v2 1/2] mtd: nand: Add Cadence NAND controller driver Date: Mon, 1 Jul 2019 11:21:36 +0100 [thread overview] Message-ID: <20190701102135.GA20033@global.cadence.com> (raw) In-Reply-To: <20190701120454.6c8ac48e@xps13> The 07/01/2019 12:04, Miquel Raynal wrote: >EXTERNAL MAIL > > >Hi Piotr, > >Piotr Sroka <piotrs@cadence.com> wrote on Mon, 1 Jul 2019 10:51:45 >+0100: > > >[...] >> >> >> > >> >> >> >This driver is way too massive, I am pretty sure it can shrink a >> >> >> >little bit more. >> >> >> >[...] >> >> >> > >> >> >> I will try to make it shorer but it will be difucult to achive. It is because - there are a lot of calculation needed for PHY - ECC are interleaved with data (like on marvell-nand or gpmi-nand). >> >> >> Therefore: + RAW mode is complicated + protecting BBM increases number of lines of source code >> >> >> - need to support two DMA engines internal and external (slave) We will see on next patch version what is the result. That page layout looks: >> >> > >> >> >Maybe you don't need to support both internal and external DMA? >> >> > >> >> >I am pretty sure there are rooms for size reduction. >> >> >> >> I describe how it works in general and maybe you help me chose better solution. >> >> >> >> HW controller can work in 3 modes. PIO - can work in master or slave DMA >> >> CDMA - needs Master DMA for accessing command descriptors. >> >> Generic mode - can use only Slave DMA. >> >> >> >> Generic mode is neccessery to implement functions other than page >> >> program, page read, block erase. So it is essential. I cannot avoid >> >> to use Slave DMA. >> > >> >This deserves a nice comment at the top. >> Ok I will add the modes description to cover letter. > > >Not only to the cover letter: People read the code. Interested people >might also read the commit log which is quite easy to find. The cover >letter however will just disappear in the history of the Internet. I >would rather prefer you explain how the IP works at the top of the >driver. So I will add the modes description to both cover letter and at the top of the driver. > > >Thanks, >Miquèl Thanks, Piotr ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/
next prev parent reply other threads:[~2019-07-01 10:22 UTC|newest] Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-02-19 16:14 [PATCH v2 0/2] mtd: nand: Add Cadence NAND controller driver Piotr Sroka 2019-02-19 16:14 ` Piotr Sroka 2019-02-19 16:18 ` [PATCH v2 1/2] " Piotr Sroka 2019-02-19 16:18 ` Piotr Sroka 2019-03-05 18:09 ` Miquel Raynal 2019-03-05 18:09 ` Miquel Raynal 2019-03-21 9:33 ` Piotr Sroka 2019-03-21 9:33 ` Piotr Sroka 2019-05-12 12:24 ` Miquel Raynal 2019-05-12 12:24 ` Miquel Raynal 2019-06-06 15:19 ` Piotr Sroka 2019-06-06 15:19 ` Piotr Sroka 2019-06-27 16:15 ` Miquel Raynal 2019-06-27 16:15 ` Miquel Raynal 2019-07-01 9:51 ` Piotr Sroka 2019-07-01 9:51 ` Piotr Sroka 2019-07-01 10:04 ` Miquel Raynal 2019-07-01 10:04 ` Miquel Raynal 2019-07-01 10:21 ` Piotr Sroka [this message] 2019-07-01 10:21 ` Piotr Sroka 2019-02-19 16:19 ` [PATCH v2 2/2] dt-bindings: " Piotr Sroka 2019-02-19 16:19 ` Piotr Sroka 2019-02-19 16:19 ` Piotr Sroka 2019-02-22 20:40 ` Rob Herring 2019-02-22 20:40 ` Rob Herring 2019-06-07 16:08 ` Piotr Sroka 2019-06-07 16:08 ` Piotr Sroka 2019-06-07 16:08 ` Piotr Sroka
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