From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 925E33D96B for ; Tue, 17 Oct 2023 08:40:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail-yw1-f181.google.com (mail-yw1-f181.google.com [209.85.128.181]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E7D45B6; Tue, 17 Oct 2023 01:40:45 -0700 (PDT) Received: by mail-yw1-f181.google.com with SMTP id 00721157ae682-5a7a80a96dbso54722247b3.0; Tue, 17 Oct 2023 01:40:45 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697532045; x=1698136845; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=KZlS/7U1efr6AK8aT2dfiOZNDdagRiOd/6FdP6Lb3EM=; b=tMM69EzZqqsRzcvNRoD0UcCKVJ0NeHuPl0kdBBEC6femOZy4FhzLEnMC4hOWqxWljx Hpu2hExeWrslfzMHTlxjYx6wAykzbUsxd9fNSktcYilF0wPSZOX4TDSJTvG8uwIFBYN+ murIh7YUwVkLC7WHdU482jrx1yEgbde8tpFcGXj+PtWtHXave6FTLOJQs81vEbKGF6+k eCXI0XqOzwdV0yNCF0CA0nzrudygqCyotxSVA9YTRqznt/WryWuRJmRNS7JFrZXgfcru gTKq/XofIpE5zUz1vwR2dyj8Wi55QA3Hzd51u1UqFeAmu+MALFJmpdZvOdcMPWkd6OIl W3hA== X-Gm-Message-State: AOJu0YzT9mcGAIq2HlFzNBJGjQdZABGYyepfOSxvR5u2Y2Ic10Hj2pXt BEtIOhsX8CIwrX08R/CH9URB7aGrqPvYtQ== X-Google-Smtp-Source: AGHT+IHtDgrSvo67YPzCatKxL+1bZQNwkrU2iyYVGsAmqHP/N/X8o3e896ZbYeWv6qt8TSdtVUVN6w== X-Received: by 2002:a05:690c:d83:b0:589:e815:8d71 with SMTP id da3-20020a05690c0d8300b00589e8158d71mr1057836ywb.11.1697532045167; Tue, 17 Oct 2023 01:40:45 -0700 (PDT) Received: from mail-yw1-f175.google.com (mail-yw1-f175.google.com. [209.85.128.175]) by smtp.gmail.com with ESMTPSA id i188-20020a8154c5000000b00589a1dc0809sm441116ywb.120.2023.10.17.01.40.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Oct 2023 01:40:44 -0700 (PDT) Received: by mail-yw1-f175.google.com with SMTP id 00721157ae682-59e88a28b98so46644637b3.1; Tue, 17 Oct 2023 01:40:44 -0700 (PDT) X-Received: by 2002:a0d:ca50:0:b0:5a7:ba02:9c9a with SMTP id m77-20020a0dca50000000b005a7ba029c9amr1017206ywd.2.1697532044608; Tue, 17 Oct 2023 01:40:44 -0700 (PDT) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20231016054755.915155-1-hch@lst.de> <20231016054755.915155-10-hch@lst.de> In-Reply-To: <20231016054755.915155-10-hch@lst.de> From: Geert Uytterhoeven Date: Tue, 17 Oct 2023 10:40:32 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 09/12] m68k: use the coherent DMA code for coldfire without data cache To: Christoph Hellwig Cc: Greg Ungerer , iommu@lists.linux.dev, Paul Walmsley , Palmer Dabbelt , Conor Dooley , Magnus Damm , Robin Murphy , Marek Szyprowski , Wei Fang , Shenwei Wang , Clark Wang , NXP Linux Team , linux-m68k@lists.linux-m68k.org, netdev@vger.kernel.org, linux-riscv@lists.infradead.org, linux-renesas-soc@vger.kernel.org, Jim Quinlan Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On Mon, Oct 16, 2023 at 7:48=E2=80=AFAM Christoph Hellwig wrot= e: > Coldfire cores configured without a data cache are DMA coherent and > should thus simply use the simple coherent version of dma-direct. > > Introduce a new COLDFIRE_COHERENT_DMA Kconfig symbol as a convenient > short hand for such configurations, and a M68K_NONCOHERENT_DMA symbol > for all cases where we need to build non-coherent DMA infrastructure > to simplify the Kconfig and code conditionals. > > Not building the non-coherent DMA code slightly reduces the code > size for such configurations. > > Numers for m5249evb_defconfig below: > > text data bss dec hex filename > 2896158 401052 65392 3362602 334f2a vmlinux.before > 2895166 400988 65392 3361546 334b0a vmlinux.after > > Signed-off-by: Christoph Hellwig The m68kclassic-with-MMU parts look fine to me, so Acked-by: Geert Uytterhoeven I'll defer to Greg for the nommu and Coldfire parts... Gr{oetje,eeting}s, Geert --=20 Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k= .org In personal conversations with technical people, I call myself a hacker. Bu= t when I'm talking to journalists I just say "programmer" or something like t= hat. -- Linus Torvalds