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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 315CDC433F5 for ; Fri, 20 May 2022 08:05:47 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4L4K6K580yz3bvM for ; Fri, 20 May 2022 18:05:45 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=PLGFqZcc; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=145.40.68.75; helo=ams.source.kernel.org; envelope-from=pali@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=PLGFqZcc; dkim-atps=neutral Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4L4K5W1GbMz3bm7 for ; Fri, 20 May 2022 18:05:02 +1000 (AEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 12792B82A59; Fri, 20 May 2022 08:04:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8E373C385A9; Fri, 20 May 2022 08:04:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653033897; bh=2+UsR8SY09lQomSf/1VOLFJ4QEsxG2ZXRneVf/dRIRQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PLGFqZccKSIjEgIWJN2VKqwQzgxTVsmT1Os/COyLLsf72r3km7q6scL8RKqTvMzGH fGGyAXIDxmixCis7kbCQUDTIFR+kkCMEKpDbG44/e4AT9f73rI8rmDq7IZV/NiGMYo fj2GQzGF5i1bTCoYocEVOl3Wu1H4tz94tet7vKNJd8ogrKJWWzKFu3b62ZZaZqMebv 3mWP3KnJvOYxTn02uLcE6bF8pPkk9iTHX4Kbr1IRhEfO6zSuL2V4+3PEzB9wns8iV9 D7I2+rPaUBv+4OIfsw3KtPCyb/q5GcgyQQzGLobuGO4KxLZJm2PW+mqJug7Ax53DtE KLNrk+p+H7yFw== Received: by pali.im (Postfix) id 3491053E; Fri, 20 May 2022 10:04:54 +0200 (CEST) Date: Fri, 20 May 2022 10:04:54 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Ash Logan Subject: Re: [PATCH 11/12] powerpc: wiiu: don't enforce flat memory Message-ID: <20220520080454.c3cqodsdbfbkmg56@pali> References: <20220302044406.63401-1-ash@heyquark.com> <20220302044406.63401-12-ash@heyquark.com> <20220513224353.n56qg5fhstbaqhfz@pali> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20180716 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, robh+dt@kernel.org, paulus@samba.org, linuxppc-dev@lists.ozlabs.org, j.ne@posteo.net Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Friday 20 May 2022 13:41:04 Ash Logan wrote: > On 14/5/22 08:43, Pali Rohár wrote: > > On Wednesday 02 March 2022 15:44:05 Ash Logan wrote: > >> pgtable_32.c:mapin_ram loops over each valid memory range, which means > >> non-contiguous memory just works. > > > > Hello! Does it mean that non-contiguous memory works for any 32-bit > > powerpc platform, and not only for wiiu? If yes, should not be > > non-contiguous memory support enabled for all 32-bit ppc boards then? > > Hi! Sorry for my delayed response. As best I can tell, it does indeed > Just Work, but I have only been able to test on wiiu which is missing a > lot of features other boards have (like PCI) - so it's possible there's > still an assumption elsewhere in the kernel that I haven't hit. > > As best I can tell, the Wii and Wii U are the only 32-bit powerpc boards > out there where it's even possible to have non-contiguous memory. What is the reason that those two boards are the **only**? Is there some specific requirement from bootloader or hardware to "enable" non-contiguous memory support? I'm interested in enabling non-contiguous memory support for P2020-based board as it has gaps in its 32-bit memory layout and which could be used for RAM mapping when 4GB DDR3 module is plugged in (default is 2GB). > >> Signed-off-by: Ash Logan > >> --- > >> arch/powerpc/mm/init_32.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c > >> index 3d690be48e84..59a84629d9a0 100644 > >> --- a/arch/powerpc/mm/init_32.c > >> +++ b/arch/powerpc/mm/init_32.c > >> @@ -125,10 +125,10 @@ void __init MMU_init(void) > >> * lowmem_end_addr is initialized below. > >> */ > >> if (memblock.memory.cnt > 1) { > >> -#ifndef CONFIG_WII > >> +#if !defined(CONFIG_WII) && !defined(CONFIG_WIIU) > >> memblock_enforce_memory_limit(memblock.memory.regions[0].size); > >> pr_warn("Only using first contiguous memory region\n"); > >> -#else > >> +#elif defined(CONFIG_WII) > >> wii_memory_fixups(); > >> #endif > >> } > >> -- > >> 2.35.1 > >>