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 75B68EB64DD for ; Tue, 4 Jul 2023 07:43:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230273AbjGDHnK convert rfc822-to-8bit (ORCPT ); Tue, 4 Jul 2023 03:43:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231127AbjGDHnI (ORCPT ); Tue, 4 Jul 2023 03:43:08 -0400 Received: from outpost1.zedat.fu-berlin.de (outpost1.zedat.fu-berlin.de [130.133.4.66]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A8D4CA; Tue, 4 Jul 2023 00:43:07 -0700 (PDT) Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1qGagf-0019oK-Cv; Tue, 04 Jul 2023 09:43:01 +0200 Received: from p57bd997f.dip0.t-ipconnect.de ([87.189.153.127] helo=[192.168.178.81]) by inpost2.zedat.fu-berlin.de (Exim 4.95) with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1qGagf-000zd1-5x; Tue, 04 Jul 2023 09:43:01 +0200 Message-ID: <1af44c63f3fdffb3bb5d0cf718cc470ef8459c33.camel@physik.fu-berlin.de> Subject: Re: [PATCH v2 3/3] sh: dma: Correct the number of DMA channels in SH7709 From: John Paul Adrian Glaubitz To: Geert Uytterhoeven Cc: Artur Rojek , Yoshinori Sato , Rich Felker , Rafael Ignacio Zurita , linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org Date: Tue, 04 Jul 2023 09:43:00 +0200 In-Reply-To: References: <20230527164452.64797-1-contact@artur-rojek.eu> <20230527164452.64797-4-contact@artur-rojek.eu> <8205bc2cb9f983914ff6920deed3f54893713ba0.camel@physik.fu-berlin.de> <485e9274ebf29da4075b40c2888f95a6cdc6d4ed.camel@physik.fu-berlin.de> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.48.3 MIME-Version: 1.0 X-Original-Sender: glaubitz@physik.fu-berlin.de X-Originating-IP: 87.189.153.127 X-ZEDAT-Hint: PO Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org Hi Geert! On Tue, 2023-07-04 at 09:32 +0200, Geert Uytterhoeven wrote: > Hi Adrian, > > On Tue, Jul 4, 2023 at 7:45 AM John Paul Adrian Glaubitz > wrote: > > On Sat, 2023-06-17 at 13:09 +0200, Geert Uytterhoeven wrote: > > > On Sat, Jun 17, 2023 at 9:32 AM John Paul Adrian Glaubitz > > > wrote: > > > > On Thu, 2023-06-08 at 12:03 +0200, John Paul Adrian Glaubitz wrote: > > > > > > > > That is actually safer, as the user can override NR_ONCHIP_DMA_CHANNELS > > > > > > > > when configuring his kernel, thus breaking DMA due to an incorrect > > > > > > > > value of SH_DMAC_NR_MD_CH. > > > > > > > > > > > > > > > > Unfortunately we cannot protect against that when using a single DMAC, > > > > > > > > as SH_DMAC_NR_MD_CH can be either 4, 6, or 8. > > > > > > > > > > > > > > > > Perhaps this configuration should be moved from Kconfig to , > > > > > > > > to protect against a user overriding this value? > > > > > > > > > > > > > > Isn't SH_DMAC_NR_MD_CH already hardwired to the SoC being used? > > > > > > > > > > > > It depends on CONFIG_NR_ONCHIP_DMA_CHANNELS, while it > > > > > > should be fixed based on the SoC. > > > > > > > > > > I agree. However, I would be fine with merging this patch set first and fixing > > > > > this particular issue in a follow-up series. > > > > > > > > So, my suggestion is to take this series as-is for 6.5, then get the other issues > > > > you mentioned fixed for 6.6. I think it's already a gain when these issues are > > > > fixed and the kernel boots on the HP Journada 680 again. > > > > > > Sure, I don't want to block the acceptance of this series at all. > > > Thanks! > > > > Apologies for the late reply. Would you mind adding your Reviewed-by to this patch > > before I review and apply the series? > > With "must be a multiply of two" and "Must be an even number" removed. > Reviewed-by: Geert Uytterhoeven Thanks. I guess, I will drop the whole "and clarify that NR_ONCHIP_DMA_CHANNELS must be a multiply of two" then. Correct? Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer `. `' Physicist `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913