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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A39CC10F11 for ; Thu, 11 Apr 2019 03:00:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 333F220818 for ; Thu, 11 Apr 2019 03:00:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726728AbfDKDAl (ORCPT ); Wed, 10 Apr 2019 23:00:41 -0400 Received: from mail-sz.amlogic.com ([211.162.65.117]:44772 "EHLO mail-sz.amlogic.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725782AbfDKDAl (ORCPT ); Wed, 10 Apr 2019 23:00:41 -0400 Received: from [10.28.18.125] (10.28.18.125) by mail-sz.amlogic.com (10.28.11.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1591.10; Thu, 11 Apr 2019 11:00:30 +0800 Subject: Re: 32-bit Amlogic (ARM) SoC: kernel BUG in kfree() To: Martin Blumenstingl CC: Matthew Wilcox , , , , , , , , , References: <20190321214401.GC19508@bombadil.infradead.org> <5cad2529-8776-687e-58d0-4fb9e2ec59b1@amlogic.com> <32799846-b8f0-758f-32eb-a9ce435e0b79@amlogic.com> <79b81748-8508-414f-c08a-c99cb4ae4b2a@amlogic.com> <8cb108ff-7a72-6db4-660d-33880fcee08a@amlogic.com> From: Liang Yang Message-ID: <45ce172c-5c76-bb69-31c8-af91e8ffdd68@amlogic.com> Date: Thu, 11 Apr 2019 11:00:31 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.28.18.125] X-ClientProxiedBy: mail-sz.amlogic.com (10.28.11.5) To mail-sz.amlogic.com (10.28.11.5) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Martin, On 2019/4/11 1:54, Martin Blumenstingl wrote: > Hi Liang, > > On Wed, Apr 10, 2019 at 1:08 PM Liang Yang wrote: >> >> Hi Martin, >> >> On 2019/4/5 12:30, Martin Blumenstingl wrote: >>> Hi Liang, >>> >>> On Fri, Mar 29, 2019 at 8:44 AM Liang Yang wrote: >>>> >>>> Hi Martin, >>>> >>>> On 2019/3/29 2:03, Martin Blumenstingl wrote: >>>>> Hi Liang, >>>> [......] >>>>>> I don't think it is caused by a different NAND type, but i have followed >>>>>> the some test on my GXL platform. we can see the result from the >>>>>> attachment. By the way, i don't find any information about this on meson >>>>>> NFC datasheet, so i will ask our VLSI. >>>>>> Martin, May you reproduce it with the new patch on meson8b platform ? I >>>>>> need a more clear and easier compared log like gxl.txt. Thanks. >>>>> your gxl.txt is great, finally I can also compare my own results with >>>>> something that works for you! >>>>> in my results (see attachment) the "DATA_IN [256 B, force 8-bit]" >>>>> instructions result in a different info buffer output. >>>>> does this make any sense to you? >>>>> >>>> I have asked our VLSI designer for explanation or simulation result by >>>> an e-mail. Thanks. >>> do you have any update on this? >> Sorry. I haven't got reply from VLSI designer yet. We tried to improve >> priority yesterday, but i still can't estimate the time. There is no >> document or change list showing the difference between m8/b and gxl/axg >> serial chips. Now it seems that we can't use command NFC_CMD_N2M on nand >> initialization for m8/b chips and use *read byte from NFC fifo register* >> instead. > thank you for the status update! > > I am trying to understand your suggestion not to use NFC_CMD_N2M: > the documentation (public S922X datasheet from Hardkernel: [0]) states > that P_NAND_BUF (NFC_REG_BUF in the meson_nand driver) can hold up to > four bytes of data. is this the "read byte from NFC FIFO register" you > mentioned? > You are right.take the early meson NFC driver V2 on previous mail as a reference. > Before I spend time changing the code to use the FIFO register I would > like to wait for an answer from your VLSI designer. > Setting the "correct" info buffer length for NFC_CMD_N2M on the 32-bit > SoCs seems like an easier solution compared to switching to the FIFO > register. Keeping NFC_CMD_N2M on the 32-bit SoCs also allows us to > have only one code-path for 32 and 64 bit SoCs, meaning we don't have > to maintain two separate code-paths for basically the same > functionality (assuming that NFC_CMD_N2M is not completely broken on > the 32-bit SoCs, we just don't know how to use it yet). > All right. I am also waiting for the answer. > > Regards > Martin > > > [0] https://dn.odroid.com/S922X/ODROID-N2/Datasheet/S922X_Public_Datasheet_V0.2.pdf > > . >