From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DC754E7849A for ; Mon, 2 Oct 2023 09:30:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236120AbjJBJa3 (ORCPT ); Mon, 2 Oct 2023 05:30:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236118AbjJBJa1 (ORCPT ); Mon, 2 Oct 2023 05:30:27 -0400 Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2B625A4 for ; Mon, 2 Oct 2023 02:30:22 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPSA id A66AB1BF204; Mon, 2 Oct 2023 09:30:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1696239021; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1nvcBaLCmY8mO5vCFGklzXqpSCLTGt+OF1cfRa4tU1I=; b=Gcu7m0Pp90GHp77BmLulIh3lxJ0ZsmBaZP25G4W3qzZoxP5zDxpwxd9xrPi9jXYNVEHQHl gs5ksdF8QBLn0dDh7DneFcTXW7sWyJgEvjsDusTLTZLpdY2bIbfiJ/qCO69QGqCnPEnM1X 5v4Zjj2T2t2a1urSFGseCBBWjFk/9JiBLRvr6FC8HksUeu2Fxuj7Xu9eGJD+KVSmqShlqx 9mAy6i19fqNtvGZ/y9RLOKrO2s07JQtVmjQjfUM7c9cTLYzzrVj/wCMHeVcmoAfYh/VF2X O2NlsZbI442Ie1NYSl6+Cnptn2zDykeaCUokAp6Gmm1dSL8uIWXqTWtwZnMH1A== Date: Mon, 2 Oct 2023 11:30:17 +0200 From: Miquel Raynal To: Nikita Shubin Cc: Rouven Czerwinski , Richard Weinberger , Vignesh Raghavendra , Arnd Bergmann , Linus Walleij , Jean Delvare , Neil Armstrong , Christophe Kerello , Chris Packham , Johan Jonker , Daniel Lezcano , linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org Subject: Re: [RFC PATCH] mtd: nand: add support for ts72xx Message-ID: <20231002113017.481aae31@xps-13> In-Reply-To: <8bbe66a23eb5c8a2404b72d754b1bcb6f4d23867.camel@maquefel.me> References: <20230927141532.25525-1-nikita.shubin@maquefel.me> <20230927172947.33106fe2@xps-13> <8bbe66a23eb5c8a2404b72d754b1bcb6f4d23867.camel@maquefel.me> Organization: Bootlin X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-GND-Sasl: miquel.raynal@bootlin.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Nikita, > ``` > # modprobe technologic-nand-controller > nand: device found, Manufacturer ID: 0xec, Chip ID: 0xf1 > nand: Samsung NAND 128MiB 3,3V 8-bit > nand: 128 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64 > Scanning device for bad blocks > Bad eraseblock 137 at 0x000001120000 > Bad eraseblock 310 at 0x0000026c0000 > 3 fixed-partitions partitions found on MTD device 60000000.nand- > controller > Creating 3 MTD partitions on "60000000.nand-controller": > 0x000000000000-0x000000020000 : "TS-BOOTROM" > 0x000000020000-0x000007d20000 : "Linux" > 0x000007d20000-0x000008000000 : "RedBoot" > ``` >=20 > This looks like Samsung K9F1G08U0D or K9F1G08U0B. >=20 > And the patch above totally solves my issues with READCACHE - thank > you! >=20 Great! > > If you are using a Micron chip that specifies not supporting ECC > > correction together with sequential cache reads, then it's a problem > > that we will solve soon (you can hardcode > > chip->controller->supported_op.cont_read to 0); > >=20 > > Otherwise we can discuss it. > > =20 > > > - legacy wait implementation had no delays - only timeout and if i > > > set=20 > > > =C2=A0 readb_poll_timeout() to something reasonable i experience speed > > > degradation=20 > > > =C2=A0 on mtd_speedtest, can it be left as 0 ? =20 > >=20 > > Looks like the legacy implementation used cond_resched(). The delay > > needs to be observed before first checking for the status, it's a > > delay > > that is described in the spec, if you get the status before you might > > just not see a consistent value. I believe that is worth taking into > > account in your implementation below (don't wait then delay, it's > > not relevant). Can you share the values you've tried and the > > performances you've got? =20 >=20 > The numbers are pretty stable, so indeed legacy is a bit faster, > followed up by new one with zero interval. ... > Legacy speedtest (old version of nand controller): > mtd_speedtest: eraseblock write speed is 3793 KiB/s > mtd_speedtest: eraseblock read speed is 3567 KiB/s > mtd_speedtest: page write speed is 3682 KiB/s > mtd_speedtest: page read speed is 3488 KiB/s > mtd_speedtest: 2 page write speed is 3724 KiB/s > mtd_speedtest: 2 page read speed is 3521 KiB/s > mtd_speedtest: erase speed is 198709 KiB/s ... =20 > New version with interval zero: > mtd_speedtest: eraseblock write speed is 3685 KiB/s > mtd_speedtest: eraseblock read speed is 3517 KiB/s > mtd_speedtest: page write speed is 3592 KiB/s > mtd_speedtest: page read speed is 3444 KiB/s > mtd_speedtest: 2 page write speed is 3608 KiB/s > mtd_speedtest: 2 page read speed is 3475 KiB/s > mtd_speedtest: erase speed is 194499 KiB/s Looks almost the same as above, I believe the difference is just noise between measurements. ... > New version with interval 100: > mtd_speedtest: eraseblock write speed is 2722 KiB/s > mtd_speedtest: eraseblock read speed is 2175 KiB/s > mtd_speedtest: page write speed is 2598 KiB/s > mtd_speedtest: page read speed is 2070 KiB/s > mtd_speedtest: 2 page write speed is 2627 KiB/s > mtd_speedtest: 2 page read speed is 2106 KiB/s > mtd_speedtest: erase speed is 175851 KiB/s ... > Also providing version with zero interval and "if (instr->delay_ns)" > dropped - it's optional as far i understood: It's not optional, sorry for the wrong comment, please keep it as it is, knowing that it will be null after a wait_rdy. > mtd_speedtest: eraseblock write speed is 3695 KiB/s > mtd_speedtest: eraseblock read speed is 3532 KiB/s > mtd_speedtest: page write speed is 3593 KiB/s > mtd_speedtest: page read speed is 3457 KiB/s > mtd_speedtest: 2 page write speed is 3640 KiB/s > mtd_speedtest: 2 page read speed is 3488 KiB/s > mtd_speedtest: erase speed is 195451 KiB/s Thanks, Miqu=C3=A8l