From nobody Sat Apr 11 07:55:53 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E50D3C25B0E for ; Sun, 14 Aug 2022 17:37:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231187AbiHNRhG (ORCPT ); Sun, 14 Aug 2022 13:37:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229555AbiHNRhD (ORCPT ); Sun, 14 Aug 2022 13:37:03 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30ED8183BB; Sun, 14 Aug 2022 10:37:03 -0700 (PDT) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.west.internal (Postfix) with ESMTP id BFB5D32004F8; Sun, 14 Aug 2022 13:37:01 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Sun, 14 Aug 2022 13:37:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sholland.org; h= cc:cc:content-transfer-encoding:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm2; t=1660498621; x=1660585021; bh=dg K2r3NnWA/fMz96186veALUGDdZnI4ai/sBIyyzgBw=; b=Ox5iXGAZAvvTwugoov Lx9ZlDx2n/7ZPiAs/SrqqRlxw08NikoDhMHPHRr77nRjDvpMLYZxoGWuqNa8AB7w Rt8xmvyvjVCsO+ArGTVqn9dHUOiDLbyLKA7f7HU78VZ6GcVHKDzHBlRDx0MiVywv 617r9jKXROg5VqhZ48gHzEFqTkLvxg+v5oDtGqL1sDwpVI8LupdPOjkpL/i7KsWt B/JplbOtKQfb27Yj9QjnF3ru4VTwcXnTnFIv9INpe3yjH+mNrYkKfHroyKug28fE iMydQpRbDIyarAg9r5dpsvSqkegLeNe9OGpAxLPOG4cDaslB0cSUBETah2MwkBCQ D4Mg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; t=1660498621; x=1660585021; bh=dgK2r3NnWA/fM z96186veALUGDdZnI4ai/sBIyyzgBw=; b=DtOqG70pJkPGoDaHvyP4tN+xEOJS/ wZ5vi1IF3AYieercncN5qi0KmqkP6RroCrk5itoeLFXNTV6yWVvQ8NIo8c7pbju5 6lxAV1QwEqMGNLYYeBSrXVguZv5+cWRdb+5s1qtjxCyeGmUYp0mTkCvWyrbP+lda H2v6aL9JS664/3si2fNeG7A4/81y/bEoUjar5wD/ZY6P14v1GZ9zGQ35o4jVCOM/ gQTR3yEPYzvjgXJSxBHwN1mkiPGbS7+jIlCEgy/2NFA/3o70BQThzzR+61mPL8Ar nLt7ofIspdZCPQ9eiFC5neTnfiXMOeg0w/9EITdiLGcvd4sCqY6Vf/3gA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrvdehtddgudduiecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvfevufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpefurghm uhgvlhcujfholhhlrghnugcuoehsrghmuhgvlhesshhhohhllhgrnhgurdhorhhgqeenuc ggtffrrghtthgvrhhnpedukeetueduhedtleetvefguddvvdejhfefudelgfduveeggeeh gfdufeeitdevteenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfh hrohhmpehsrghmuhgvlhesshhhohhllhgrnhgurdhorhhg X-ME-Proxy: Feedback-ID: i0ad843c9:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sun, 14 Aug 2022 13:37:00 -0400 (EDT) From: Samuel Holland To: Srinivas Kandagatla , Chen-Yu Tsai , Jernej Skrabec Cc: Samuel Holland , Greg Kroah-Hartman , Krzysztof Kozlowski , Rob Herring , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@lists.linux.dev Subject: [PATCH 1/4] nvmem: sunxi_sid: Always use 32-bit MMIO reads Date: Sun, 14 Aug 2022 12:36:52 -0500 Message-Id: <20220814173656.11856-2-samuel@sholland.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220814173656.11856-1-samuel@sholland.org> References: <20220814173656.11856-1-samuel@sholland.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 =3D=3D 1 for sysfs ABI compatibility, as noted previously in commit de2a3eaea552 ("nvmem: sunxi_sid: Optimize register read-out method"). Fixes: 07ae4fde9efa ("nvmem: sunxi_sid: Add support for D1 variant") Signed-off-by: Samuel Holland Reviewed-by: Jernej Skrabec Tested-by: Heiko Stuebner --- drivers/nvmem/sunxi_sid.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c index 5750e1f4bcdb..92dfe4cb10e3 100644 --- a/drivers/nvmem/sunxi_sid.c +++ b/drivers/nvmem/sunxi_sid.c @@ -41,8 +41,21 @@ static int sunxi_sid_read(void *context, unsigned int of= fset, void *val, size_t bytes) { struct sunxi_sid *sid =3D context; + u32 word; + + /* .stride =3D 4 so offset is guaranteed to be aligned */ + __ioread32_copy(val, sid->base + sid->value_offset + offset, bytes / 4); =20 - memcpy_fromio(val, sid->base + sid->value_offset + offset, bytes); + val +=3D round_down(bytes, 4); + offset +=3D round_down(bytes, 4); + bytes =3D bytes % 4; + + if (!bytes) + return 0; + + /* Handle any trailing bytes */ + word =3D readl_relaxed(sid->base + sid->value_offset + offset); + memcpy(val, &word, bytes); =20 return 0; } --=20 2.35.1