From patchwork Mon May 22 07:38:35 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Brezillon X-Patchwork-Id: 765279 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3wWVsb3hwCz9ryQ for ; Mon, 22 May 2017 17:39:15 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="SavzzUvZ"; dkim-atps=neutral DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=zDFaSjrNs97l3gqpFuxoFZvKnURAt8A+4aCWXcZPW/A=; b=SavzzUvZpvT5uK rwZBKm5ybS8Z4nvSMi2XjfqUk+Nj+zenjgMcO7kN5tEOBX6fDDn/WXs0ymKLR38LUfzCtx866lNPD ey2XzWxKQEiSegQnKgM5VGIrfDFDqUpi0U7er/Cc8DBSxk1tkixPy8kUlzNMZo0wRhSxzaRIIJ/Dn 4gR0lPovO66GKz8UylQvDpD+7a72z0ZY+8nDObvTseILygr96DxfRW08XnckWZLX8kG5hotmaugDw TX/aLKgo2k8pzN2+soqH+77jZ5godFoPHRP6QXvK4P670huwVz3ZP9ZetdEohUoSx4bbJ1XZzgOTt ZSgp2ky161PkjIW6KTDA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dChvr-0001LC-S8; Mon, 22 May 2017 07:39:11 +0000 Received: from mail.free-electrons.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dChvn-0001J2-To for linux-mtd@lists.infradead.org; Mon, 22 May 2017 07:39:10 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id 5E88D206E1; Mon, 22 May 2017 09:38:45 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.4.0 Received: from bbrezillon (LStLambert-657-1-97-87.w90-63.abo.wanadoo.fr [90.63.216.87]) by mail.free-electrons.com (Postfix) with ESMTPSA id 1BA95206E2; Mon, 22 May 2017 09:38:35 +0200 (CEST) Date: Mon, 22 May 2017 09:38:35 +0200 From: Boris Brezillon To: Chris Packham Subject: Re: [PATCH 3/4] mtd: mchp23k256: add partitioning support Message-ID: <20170522093835.70f7f110@bbrezillon> In-Reply-To: <31c94577108c42c1b51d410081d97eb5@svr-chch-ex1.atlnz.lc> References: <20170517053908.26138-1-chris.packham@alliedtelesis.co.nz> <20170517053908.26138-4-chris.packham@alliedtelesis.co.nz> <20170517172911.5f926712@bbrezillon> <31c94577108c42c1b51d410081d97eb5@svr-chch-ex1.atlnz.lc> X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170522_003908_251787_EEA2C634 X-CRM114-Status: GOOD ( 26.56 ) X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.4.1 on bombadil.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "andrew@lunn.ch" , Richard Weinberger , "linux-kernel@vger.kernel.org" , Marek Vasut , "linux-mtd@lists.infradead.org" , Cyrille Pitchen , "computersforpeace@gmail.com" , "dwmw2@infradead.org" Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Hi Chris, On Mon, 22 May 2017 04:52:34 +0000 Chris Packham wrote: > On 18/05/17 03:29, Boris Brezillon wrote: > > Hi Chris, > > > > On Wed, 17 May 2017 17:39:07 +1200 > > Chris Packham wrote: > > > >> Setting the of_node for the mtd device allows the generic mtd code to > >> setup the partitions. Additionally we must specify a non-zero erasesize > >> for the partitions to be writeable. > >> > >> Signed-off-by: Chris Packham > >> --- > >> drivers/mtd/devices/mchp23k256.c | 5 +++++ > >> 1 file changed, 5 insertions(+) > >> > >> diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c > >> index 2542f5b8b63f..02c6b9dcbd3e 100644 > >> --- a/drivers/mtd/devices/mchp23k256.c > >> +++ b/drivers/mtd/devices/mchp23k256.c > >> @@ -143,6 +143,7 @@ static int mchp23k256_probe(struct spi_device *spi) > >> > >> data = dev_get_platdata(&spi->dev); > >> > >> + mtd_set_of_node(&flash->mtd, spi->dev.of_node); > >> flash->mtd.dev.parent = &spi->dev; > >> flash->mtd.type = MTD_RAM; > >> flash->mtd.flags = MTD_CAP_RAM; > >> @@ -151,6 +152,10 @@ static int mchp23k256_probe(struct spi_device *spi) > >> flash->mtd._read = mchp23k256_read; > >> flash->mtd._write = mchp23k256_write; > >> > >> + flash->mtd.erasesize = PAGE_SIZE; > >> + while (flash->mtd.size & (flash->mtd.erasesize - 1)) > >> + flash->mtd.erasesize >>= 1; > >> + > > > > Can we fix allocate_partition() to properly handle the > > master->erasesize == 0 case instead of doing that? > > > > Do you mean something like this? I had something slightly different in mind (see below). > > diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c > index ea5e5307f667..0cd20ed6b374 100644 > --- a/drivers/mtd/mtdpart.c > +++ b/drivers/mtd/mtdpart.c > @@ -577,6 +577,7 @@ static struct mtd_part *allocate_partition(struct > mtd_info *master, > part->name); > } > if ((slave->mtd.flags & MTD_WRITEABLE) && > + master->erasesize != 0 && > mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) { > slave->mtd.flags &= ~MTD_WRITEABLE; > > > I'm happy to submit this as a formal patch but it could potentially > affect a number of devices. Whereas the snippet I initially added is > consistent with drivers/mtd/chips/map_ram.c. Well, if you're duplicating a workaround that's a good sign this should actually be handled in the core. > > For now I'll leave v2 as-is but I can send a v3 if needed. > --->8--- diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index ea5e5307f667..378ff4a9174e 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -393,7 +393,9 @@ static struct mtd_part *allocate_partition(struct mtd_info *master, const struct mtd_partition *part, int partno, uint64_t cur_offset) { + int wr_alignment = master->erasesize ? : master->writesize; struct mtd_part *slave; + u32 remainder; char *name; /* allocate the partition structure */ @@ -499,10 +501,12 @@ static struct mtd_part *allocate_partition(struct mtd_info *master, if (slave->offset == MTDPART_OFS_APPEND) slave->offset = cur_offset; if (slave->offset == MTDPART_OFS_NXTBLK) { + u64 tmp = cur_offset; + slave->offset = cur_offset; - if (mtd_mod_by_eb(cur_offset, master) != 0) { - /* Round up to next erasesize */ - slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize; + remainder = do_div(tmp, wr_alignment); + if (remainder) { + slave->offset += wr_alignment - remainder; printk(KERN_NOTICE "Moving partition %d: " "0x%012llx -> 0x%012llx\n", partno, (unsigned long long)cur_offset, (unsigned long long)slave->offset); @@ -567,19 +571,22 @@ static struct mtd_part *allocate_partition(struct mtd_info *master, slave->mtd.erasesize = master->erasesize; } - if ((slave->mtd.flags & MTD_WRITEABLE) && - mtd_mod_by_eb(slave->offset, &slave->mtd)) { + tmp = slave->offset; + remainder = do_div(tmp, wr_alignment); + if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) { /* Doesn't start on a boundary of major erase size */ /* FIXME: Let it be writable if it is on a boundary of * _minor_ erase size though */ slave->mtd.flags &= ~MTD_WRITEABLE; - printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n", + printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n", part->name); } - if ((slave->mtd.flags & MTD_WRITEABLE) && - mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) { + + tmp = slave->mtd.size; + remainder = do_div(tmp, wr_alignment); + if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) { slave->mtd.flags &= ~MTD_WRITEABLE; - printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n", + printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n", part->name); }