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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 42D4AEB64D9 for ; Fri, 7 Jul 2023 12:26:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=waHowEGHIdH50Dd3z4IF+qfogAGrwK2w1XZGlhc7e0I=; b=QB/yVXJO1BM/6k nxxPJHv24wtoarHpdoFucYs650klS18LOVieF+irjnYt5AI4z3A9Z1m/7ebveYOT32aGmgH2GlrfP 39KNLxLtbh0a0RtSnh3JjBImZpy2gbNbOOtrN0urjF+Gc242VY3dtSWpGv5plUliMn6RJdPVuR+v9 R4qJ4kY3J2c1AuuUW9jKoyYSkk4qML6PWPRWZHPBK/GO3TUuq7nPU8+dDhO0MpC6U6K01lrajNrCa 7cBChP5t4L1tm/ACavYrpWquxD4XshoCc4JZlUhyMm/vuRqN1rhfu/OpDhM4IEiwtsVaIGYwO4GVm WJpELeLnvgTNHkRPtomw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qHkX7-004cJC-36; Fri, 07 Jul 2023 12:25:57 +0000 Received: from mx1.tq-group.com ([93.104.207.81]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qHkX4-004cI1-1J for linux-arm-kernel@lists.infradead.org; Fri, 07 Jul 2023 12:25:56 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1688732754; x=1720268754; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fHVHlYyXVX/im36hgUnWjYzXHXB5AFCDep27NaHMXWM=; b=hO2Zx0f1ayzqevaXy5SlTIWIlknQ7Tu6LQnKXnIScE63sVq5wAmKGue2 0u5ggkKJECRFCLd65XWcmQvDu/iJ/U3beDyR0BVEKHPAzYZfSxYJvyhee yGnfYwQo0aj92os/4XPbAUWQLI5efwUZZk/bbHXo5y9oPrvSKkj0EEN0z mpqHF7MWRysxbYwsvrGba0IRmcKVe0z4iLZicmeuTNtnb6Tik3tQylCMP axUCaPF43Ra4Jm05sFohvuvHhPoce34h93zSB8GIycbc8FsLpN82tJnyC ACRCOZ+ue5IYLnHr63Yo+L64CoPAHdJBaOFAVln/M3VFvlJiJQDmM4XI2 g==; X-IronPort-AV: E=Sophos;i="6.01,187,1684792800"; d="scan'208";a="31813721" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 07 Jul 2023 14:25:49 +0200 Received: from steina-w.localnet (unknown [10.123.53.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by vtuxmail01.tq-net.de (Postfix) with ESMTPSA id 97C4E280084; Fri, 7 Jul 2023 14:25:49 +0200 (CEST) From: Alexander Stein To: Frank Li , Robin Murphy Cc: Lucas Stach , suzuki.poulose@arm.com, coresight@lists.linaro.org, imx@lists.linux.dev, Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Marek Vasut , Peng Fan , Adam Ford , Laurent Pinchart , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , open list Subject: Re: [PATCH 1/1] arm64: dts: imx8mp: remove arm, primecell-periphid at etm nodes Date: Fri, 07 Jul 2023 14:25:49 +0200 Message-ID: <6505804.Sb9uPGUboI@steina-w> Organization: TQ-Systems GmbH In-Reply-To: <5cf23bfd-a3b7-3dde-146b-4892d75b3485@arm.com> References: <20230705205954.4159781-1-Frank.Li@nxp.com> <24260662.6Emhk5qWAg@steina-w> <5cf23bfd-a3b7-3dde-146b-4892d75b3485@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230707_052554_829985_A0AF4B5E X-CRM114-Status: GOOD ( 33.88 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Robin, Am Freitag, 7. Juli 2023, 10:50:31 CEST schrieb Robin Murphy: > On 2023-07-07 06:34, Alexander Stein wrote: > > Hi Frank, > > = > > Am Donnerstag, 6. Juli 2023, 16:39:07 CEST schrieb Frank Li: > >> On Thu, Jul 06, 2023 at 12:06:19PM +0100, Robin Murphy wrote: > >>>>> Am Mittwoch, 5. Juli 2023, 22:59:53 CEST schrieb Frank Li: > >>>>>> The reg size of etm nodes is incorrectly set to 64k instead of 4k. > >>>>>> This > >>>>>> leads to a crash when calling amba_read_periphid(). After correct= ed > >>>>>> reg > >>>>>> size, amba_read_periphid() retrieve the correct periphid. > >>>>>> arm,primecell-periphid were removed from the etm nodes. > >>>>> = > >>>>> So this means the reference manual is wrong here? It clearly states > >>>>> the size is 64kiB. Reference Manual i.MX8MP Rev 1. 06/2021 > >>>>> On a side note: Is imx8mq affected by this as well? The DAP memory > >>>>> table lists similar sizes in the RM . > >>>> = > >>>> Note that the 64K MMIO space per device is really an alignment thing. > >>>> It's a recommendation from ARM to allow individual device MMIO regio= ns > >>>> to be mapped on kernels with 64K page size. Most of the time the real > >>>> MMIO space occupied by the device is actually much smaller than 64K. > >>> = > >>> Indeed, it's quite common for TRM memory maps to be written in terms = of > >>> the > >>> interconnect configuration, i.e. from the point of view of the > >>> interconnect > >>> itself, that whole range of address space is assigned to that > >>> peripheral, > >>> and it may even be true that the entire range is routed to the port > >>> where > >>> that peripheral is connected. However what's of more interest for DT = is > >>> how > >>> much of that range the peripheral itself actually decodes. > >> = > >> Yes, there are not problem by mapping bigger space in most case. > >> = > >> amba bus's periphal use close to end of region to show device's identi= cal > >> information. > > = > > Ah, thanks for the explanation. This make things more clear. > > But on the other is it sensible to assume the memory resource size to f= it > > the IP address space? It appears to me the size is fixed to 4kiB anyway. > > Would it make more sense to read the values from the address "base + 4K= - > > x" instead of "base + size - x"? > = > The size of PrimeCell components in general isn't necessarily 4KB > though, and the ID registers were defined relative to the *end* of the > register space. The old PrimeCell standards evolved into the CoreSight > spec, and from the oldest version of that I can easily link to[1]: > = > "Each component occupies one or more contiguous 4KB blocks of address > space. Where a component occupies more than one 4KB block, these > registers must appear in the highest 4KB block." > = > (FWIW the latest Coresight 3.0 spec relaxes this restriction, but we > tend to model newer stuff as platform drivers with explicit DT/ACPI > identifiers rather than amba drivers anyway) Ah, I wasn't aware the register space for PrimeCells/CoreSight could be lar= ger = than 4k. So the exact size must be known and used in DT. Thanks for = explanation. Best regards, Alexander > Thanks, > Robin. > = > [1] https://developer.arm.com/documentation/ihi0029/d/?lang=3Den > = > > Best regards, > > Alexander > > = > >> In drivers/amba/bus.c, > >> = > >> amba_read_periphid() > >> { > >> = > >> ... > >> size =3D resource_size(&dev->res); > >> ... > >> for (pid =3D 0, i =3D 0; i < 4; i++) > >> = > >> pid |=3D (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * > > = > > 8); > > = > >> } > >> = > >> So the range in DTS for arm,primecell should be actual IP address spac= e. > >> = > >>> Robin. > >>> = > >>>> _______________________________________________ > >>>> linux-arm-kernel mailing list > >>>> linux-arm-kernel@lists.infradead.org > >>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- = TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht M=FCnchen, HRB 105018 Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider http://www.tq-group.com/ _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel