From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B2F601859 for ; Sun, 8 Jan 2023 20:52:14 +0000 (UTC) Received: by mail-ed1-f44.google.com with SMTP id c17so9814464edj.13 for ; Sun, 08 Jan 2023 12:52:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=/W1ZH7okdp3bC5pjHi5v6nQazt9WUGWbkW62SJcD8hQ=; b=CZSi5VCe45fYPvoueF3Xz9/2f8RQXo4zyAt34wYxgvnxVuDjBRRzHICHSsCVFL9qvD y0k+0LPoVdQjSsrczYbF/yitqgcOmTgTpEhjZtjt3K0/vdqY5X6LE/vA8Fahyg8LBmDb JgHj7ZOPWTu5jVphQgd2X6yMgiB49QeVi3N0e+QyysPEGlgHC2MSxjtVjIIvUA/FAPRj S2/zFCg6UTJiLPOnA34xzSUTpD7z1bpfhFvFx175/mX+wgOxWh3adhrMU+ehQ0Yfx+qm 4zBi2y/2PuqdbZfQq8N2IMW2hGoNSPkVsIURkr3reDhJWPsvh63lvhO3Fate3WhzcCbZ oqTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/W1ZH7okdp3bC5pjHi5v6nQazt9WUGWbkW62SJcD8hQ=; b=3u5vnA+ffu0glCzS76VuTYPIzJSeY/Y/vVuDsBS+Sm3tVPwtdVEHI2+nEpwknPxmzb zrr+RGkeq59Cbs15zeZEVXCRNXLtJkzS9Izlj+oKAABZT4UDQ2BKvehtfPmCK88SRCE1 R37Ym9gaY5yMx3XIS0kXErUlHXZVqpmLUDFC7dxGO5RYDJb3+LjaNG9GeCNADhsb8EuJ 1Jjr2nF1YmGPPZcud9VGYN7EPfLmRCj3keV/JhGl2qNJkci8GokSEkmRfaft+VTuB8xW eHI6iq9/oyGU9ECcEgRkWCvgdGvTktEdQEv9Me2AYrke+9iQJhGbjmyGrMIofFtJInao W15A== X-Gm-Message-State: AFqh2kp9z24R4jOz8VWmZrmwdrgqr9Cu4SxOW6tOjZzS55axVGv8oR9E SPbD7U0HIy7kmv5uT7BklaNX4Jj2qj2Gz1Hh X-Google-Smtp-Source: AMrXdXthkxdR5S3Vx/C5pVKc8nmwQsnxhLxbv5FwkjZ/fyeqvLUsh+ZvJxXis6Q2Ef7PtQwkRWND5A== X-Received: by 2002:a05:6402:104d:b0:486:ac69:b9e4 with SMTP id e13-20020a056402104d00b00486ac69b9e4mr36935941edu.4.1673211133033; Sun, 08 Jan 2023 12:52:13 -0800 (PST) Received: from jernej-laptop.localnet (82-149-19-102.dynamic.telemach.net. [82.149.19.102]) by smtp.gmail.com with ESMTPSA id k26-20020a508ada000000b00487fc51c532sm3016451edk.33.2023.01.08.12.52.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Jan 2023 12:52:12 -0800 (PST) From: Jernej =?utf-8?B?xaBrcmFiZWM=?= To: Srinivas Kandagatla , Chen-Yu Tsai , Samuel Holland Cc: Samuel Holland , Greg Kroah-Hartman , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@lists.linux.dev, stable@vger.kernel.org, Heiko Stuebner Subject: Re: [PATCH v2 1/2] nvmem: sunxi_sid: Always use 32-bit MMIO reads Date: Sun, 08 Jan 2023 21:52:11 +0100 Message-ID: <5829449.MhkbZ0Pkbq@jernej-laptop> In-Reply-To: <20230101183316.43642-2-samuel@sholland.org> References: <20230101183316.43642-1-samuel@sholland.org> <20230101183316.43642-2-samuel@sholland.org> Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Dne nedelja, 01. januar 2023 ob 19:33:15 CET je Samuel Holland napisal(a): > The SID SRAM on at least some SoCs (A64 and D1) returns different values > when read with bus cycles narrower than 32 bits. This is not immediately > obvious, because memcpy_fromio() uses word-size accesses as long as > enough data is being copied. > > The vendor driver always uses 32-bit MMIO reads, so do the same here. > This is faster than the register-based method, which is currently used > as a workaround on A64. And it fixes the values returned on D1, where > the SRAM method was being used. > > The special case for the last word is needed to maintain .word_size == 1 > for sysfs ABI compatibility, as noted previously in commit de2a3eaea552 > ("nvmem: sunxi_sid: Optimize register read-out method"). > > Cc: stable@vger.kernel.org > Fixes: 07ae4fde9efa ("nvmem: sunxi_sid: Add support for D1 variant") > Tested-by: Heiko Stuebner > Signed-off-by: Samuel Holland Reviewed-by: Jernej Skrabec Best regards, Jernej