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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19A09C77B7D for ; Mon, 15 May 2023 11:00:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240584AbjEOLAA (ORCPT ); Mon, 15 May 2023 07:00:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229963AbjEOK75 (ORCPT ); Mon, 15 May 2023 06:59:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A76F912E; Mon, 15 May 2023 03:59:56 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 3C9D86227C; Mon, 15 May 2023 10:59:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C90AC433D2; Mon, 15 May 2023 10:59:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684148395; bh=aaXWGFW+W+Mx8ejKT43D62hQkzh/cnrA202CHaOIB0E=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=cinKTZS02ZdwiyFq5/nt+Upe7lCXbgUPqNR9AhZfckd5rzhO9QU90GgbLvZ4QWbko vsg5v4oexO+PPAMxwfq+YTRH9+gxeOjz2FD09+GrTQRIVcwge7tqqcp00K7T8USMTV 0AWv6mjVF80KB8jSRtW2wRP19BRqKUIy4qg3hkrQdUaO5GSksoBRGT0NNG2+PJ8wLN Mr1eZ1BSKharxEFkA84pNQFgURked16MwqWgvr52X83oh1qIeLEW8p4SWweB9qSMTQ mWGT4tBfWfeEFn4gTzjum8kKPk57568J3O6mrFyS5UB3iOerxhYppqTLpr/gf/V3lp zQ6XS1PjNeDUg== From: Kalle Valo To: Ping-Ke Shih Cc: Martin Blumenstingl , "linux-wireless\@vger.kernel.org" , "linux-kernel\@vger.kernel.org" , "tony0620emma\@gmail.com" , Larry Finger , Rudi Heitbaum Subject: Re: [PATCH wireless v1] wifi: rtw88: sdio: Always use two consecutive bytes for word operations References: <20230514200345.502807-1-martin.blumenstingl@googlemail.com> Date: Mon, 15 May 2023 13:59:50 +0300 In-Reply-To: (Ping-Ke Shih's message of "Mon, 15 May 2023 00:36:27 +0000") Message-ID: <87mt25n9ll.fsf@kernel.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ping-Ke Shih writes: >> -----Original Message----- >> From: Martin Blumenstingl >> Sent: Monday, May 15, 2023 4:04 AM >> To: linux-wireless@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org; Ping-Ke Shih ; tony0620emma@gmail.com; >> kvalo@kernel.org; Martin Blumenstingl ; Larry Finger >> ; Rudi Heitbaum >> Subject: [PATCH wireless v1] wifi: rtw88: sdio: Always use two consecutive bytes for word operations >> >> The Allwinner sunxi-mmc controller cannot handle word (16 bit) >> transfers. So and sdio_{read,write}w fails with messages like the >> following example using an RTL8822BS (but the same problems were also >> observed with RTL8822CS and RTL8723DS chips): >> rtw_8822bs mmc1:0001:1: Firmware version 27.2.0, H2C version 13 >> sunxi-mmc 4021000.mmc: unaligned scatterlist: os f80 length 2 >> sunxi-mmc 4021000.mmc: map DMA failed >> rtw_8822bs mmc1:0001:1: sdio read16 failed (0x10230): -22 >> >> Use two consecutive single byte accesses for word operations instead. It >> turns out that upon closer inspection this is also what the vendor >> driver does, even though it does have support for sdio_{read,write}w. So >> we can conclude that the rtw88 chips do support word access but only on >> SDIO controllers that also support it. Since there's no way to detect if >> the controller supports word access or not the rtw88 sdio driver >> switches to the easiest approach: avoiding word access. >> >> Reported-by: Larry Finger >> Closes: https://lore.kernel.org/linux-wireless/527585e5-9cdd-66ed-c3af-6da162f4b720@lwfinger.net/ > > "Closes:" seems not a regular tag. Use "Link: " instead. Actually the documentation now talks about Closes tag: https://docs.kernel.org/process/5.Posting.html#patch-formatting-and-changelogs I guess this tag is a recent addition? -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches