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 179BFC433FE for ; Tue, 22 Mar 2022 03:01:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235800AbiCVDCn (ORCPT ); Mon, 21 Mar 2022 23:02:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235759AbiCVDCl (ORCPT ); Mon, 21 Mar 2022 23:02:41 -0400 Received: from vps0.lunn.ch (vps0.lunn.ch [185.16.172.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3044541A2; Mon, 21 Mar 2022 20:01:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Transfer-Encoding:Content-Disposition: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:From: Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Content-Disposition: In-Reply-To:References; bh=b9U/YwFXv20yTfLFWbuRAqJRHhEpMtnMkWj3xf7Fzmc=; b=UI EEw8H1dCe2232LDPhplovW5e6NBNhkEiNVcTx8Gi+C/x/aWmMF0oZf5UfZpX9ycafyR2rIwhvk8lb S/63ptPf6TBvFK8o+Ed2oh96jDXeLIDwEiH9B/Kpyln2pE00hYBEMbinj77+zZNRU1jjfimUnpmqq vVUHfXSoVMB8oGM=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1nWUlH-00C3s4-PQ; Tue, 22 Mar 2022 04:00:43 +0100 Date: Tue, 22 Mar 2022 04:00:43 +0100 From: Andrew Lunn To: Dylan Hung Cc: Krzysztof Kozlowski , "robh+dt@kernel.org" , "joel@jms.id.au" , "andrew@aj.id.au" , "hkallweit1@gmail.com" , "linux@armlinux.org.uk" , "davem@davemloft.net" , "kuba@kernel.org" , "pabeni@redhat.com" , "p.zabel@pengutronix.de" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-aspeed@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , BMC-SW , "stable@vger.kernel.org" Subject: Re: [PATCH v2 3/3] ARM: dts: aspeed: add reset properties into MDIO nodes Message-ID: References: <20220321095648.4760-1-dylan_hung@aspeedtech.com> <20220321095648.4760-4-dylan_hung@aspeedtech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 22, 2022 at 02:32:13AM +0000, Dylan Hung wrote: > > -----Original Message----- > > From: Krzysztof Kozlowski [mailto:krzk@kernel.org] > > Sent: 2022年3月21日 11:53 PM > > To: Dylan Hung ; robh+dt@kernel.org; > > joel@jms.id.au; andrew@aj.id.au; andrew@lunn.ch; hkallweit1@gmail.com; > > linux@armlinux.org.uk; davem@davemloft.net; kuba@kernel.org; > > pabeni@redhat.com; p.zabel@pengutronix.de; devicetree@vger.kernel.org; > > linux-arm-kernel@lists.infradead.org; linux-aspeed@lists.ozlabs.org; > > linux-kernel@vger.kernel.org; netdev@vger.kernel.org > > Cc: BMC-SW ; stable@vger.kernel.org > > Subject: Re: [PATCH v2 3/3] ARM: dts: aspeed: add reset properties into MDIO > > nodes > > > > On 21/03/2022 10:56, Dylan Hung wrote: > > > Add reset control properties into MDIO nodes. The 4 MDIO controllers in > > > AST2600 SOC share one reset control bit SCU50[3]. > > > > > > Signed-off-by: Dylan Hung > > > Cc: stable@vger.kernel.org > > > > Please describe the bug being fixed. See stable-kernel-rules. > > Thank you for your comment. > The reset deassertion of the MDIO device was usually done by the bootloader (u-boot). > However, one of our clients uses proprietary bootloader and doesn't deassert the MDIO > reset so failed to access the HW in kernel driver. So are you saying mainline u-boot releases the reset? > The reset deassertion is missing in the > kernel driver since it was created, should I add a BugFix for the first commit of this driver? Yes, that is normal. Ideally the kernel should not depend on u-boot, because often people want to use other bootloaders, e.g. barebox. You should also consider kexec, where one kernel hands over to another kernel, without the bootloader being involved. In such a situation, you ideally want to assert and deassert the reset just to clean away any state the old kernel left around. But please do note, that the reset is optional, since you need to be able to work with old DT blobs which don't have the reset property in them. Andrew 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3CE72C433F5 for ; Tue, 22 Mar 2022 03:02:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZoNRql2NhyBVzz2GxJdnwZTp6Pkq5x29SFnUFCHYmR8=; b=PeDqxrnvWaBnjZ l6Cf1AJMDexPC0zokfK319ESrBR4qDU3GL2MXIAyN8h5K3HW7ldBqgrLJkN+g5jsQFNHpAGTVv9sA oZpL6WarbQdm8LuHqh/gLzVOBJ4cdBmxUkM7lQwK9ZuviOg0V7qu8rcW8Ryk+JVcxcjd6f8fjYxlM BaIFEcVJNakJTPZGBbJLNrpEmezjEbU/yinECdQ5HljXRDHxweNtCY3AVdIbizso7RU5Ktnjp6ko/ 1EdEDiE/Guqwor91i46R2Mz2g/15ZcqlNwWTRsYR1tox7FegR1ChTVYHJl5hZbbbv6ec/k1qMYvCJ sfO8HtxIkpcLh8vBfoyg==; 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Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1nWUlH-00C3s4-PQ; Tue, 22 Mar 2022 04:00:43 +0100 Date: Tue, 22 Mar 2022 04:00:43 +0100 From: Andrew Lunn To: Dylan Hung Cc: Krzysztof Kozlowski , "robh+dt@kernel.org" , "joel@jms.id.au" , "andrew@aj.id.au" , "hkallweit1@gmail.com" , "linux@armlinux.org.uk" , "davem@davemloft.net" , "kuba@kernel.org" , "pabeni@redhat.com" , "p.zabel@pengutronix.de" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-aspeed@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , BMC-SW , "stable@vger.kernel.org" Subject: Re: [PATCH v2 3/3] ARM: dts: aspeed: add reset properties into MDIO nodes Message-ID: References: <20220321095648.4760-1-dylan_hung@aspeedtech.com> <20220321095648.4760-4-dylan_hung@aspeedtech.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220321_200104_878262_9BCB0040 X-CRM114-Status: GOOD ( 19.77 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gVHVlLCBNYXIgMjIsIDIwMjIgYXQgMDI6MzI6MTNBTSArMDAwMCwgRHlsYW4gSHVuZyB3cm90 ZToKPiA+IC0tLS0tT3JpZ2luYWwgTWVzc2FnZS0tLS0tCj4gPiBGcm9tOiBLcnp5c3p0b2YgS296 bG93c2tpIFttYWlsdG86a3J6a0BrZXJuZWwub3JnXQo+ID4gU2VudDogMjAyMuW5tDPmnIgyMeaX pSAxMTo1MyBQTQo+ID4gVG86IER5bGFuIEh1bmcgPGR5bGFuX2h1bmdAYXNwZWVkdGVjaC5jb20+ OyByb2JoK2R0QGtlcm5lbC5vcmc7Cj4gPiBqb2VsQGptcy5pZC5hdTsgYW5kcmV3QGFqLmlkLmF1 OyBhbmRyZXdAbHVubi5jaDsgaGthbGx3ZWl0MUBnbWFpbC5jb207Cj4gPiBsaW51eEBhcm1saW51 eC5vcmcudWs7IGRhdmVtQGRhdmVtbG9mdC5uZXQ7IGt1YmFAa2VybmVsLm9yZzsKPiA+IHBhYmVu aUByZWRoYXQuY29tOyBwLnphYmVsQHBlbmd1dHJvbml4LmRlOyBkZXZpY2V0cmVlQHZnZXIua2Vy bmVsLm9yZzsKPiA+IGxpbnV4LWFybS1rZXJuZWxAbGlzdHMuaW5mcmFkZWFkLm9yZzsgbGludXgt YXNwZWVkQGxpc3RzLm96bGFicy5vcmc7Cj4gPiBsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3Jn OyBuZXRkZXZAdmdlci5rZXJuZWwub3JnCj4gPiBDYzogQk1DLVNXIDxCTUMtU1dAYXNwZWVkdGVj aC5jb20+OyBzdGFibGVAdmdlci5rZXJuZWwub3JnCj4gPiBTdWJqZWN0OiBSZTogW1BBVENIIHYy IDMvM10gQVJNOiBkdHM6IGFzcGVlZDogYWRkIHJlc2V0IHByb3BlcnRpZXMgaW50byBNRElPCj4g PiBub2Rlcwo+ID4gCj4gPiBPbiAyMS8wMy8yMDIyIDEwOjU2LCBEeWxhbiBIdW5nIHdyb3RlOgo+ ID4gPiBBZGQgcmVzZXQgY29udHJvbCBwcm9wZXJ0aWVzIGludG8gTURJTyBub2Rlcy4gIFRoZSA0 IE1ESU8gY29udHJvbGxlcnMgaW4KPiA+ID4gQVNUMjYwMCBTT0Mgc2hhcmUgb25lIHJlc2V0IGNv bnRyb2wgYml0IFNDVTUwWzNdLgo+ID4gPgo+ID4gPiBTaWduZWQtb2ZmLWJ5OiBEeWxhbiBIdW5n IDxkeWxhbl9odW5nQGFzcGVlZHRlY2guY29tPgo+ID4gPiBDYzogc3RhYmxlQHZnZXIua2VybmVs Lm9yZwo+ID4gCj4gPiBQbGVhc2UgZGVzY3JpYmUgdGhlIGJ1ZyBiZWluZyBmaXhlZC4gU2VlIHN0 YWJsZS1rZXJuZWwtcnVsZXMuCj4gCj4gVGhhbmsgeW91IGZvciB5b3VyIGNvbW1lbnQuCj4gVGhl IHJlc2V0IGRlYXNzZXJ0aW9uIG9mIHRoZSBNRElPIGRldmljZSB3YXMgdXN1YWxseSBkb25lIGJ5 IHRoZSBib290bG9hZGVyICh1LWJvb3QpLgo+IEhvd2V2ZXIsIG9uZSBvZiBvdXIgY2xpZW50cyB1 c2VzIHByb3ByaWV0YXJ5IGJvb3Rsb2FkZXIgYW5kIGRvZXNuJ3QgZGVhc3NlcnQgdGhlIE1ESU8K PiByZXNldCBzbyBmYWlsZWQgdG8gYWNjZXNzIHRoZSBIVyBpbiBrZXJuZWwgZHJpdmVyLgoKU28g YXJlIHlvdSBzYXlpbmcgbWFpbmxpbmUgdS1ib290IHJlbGVhc2VzIHRoZSByZXNldD8KCj4gVGhl IHJlc2V0IGRlYXNzZXJ0aW9uIGlzIG1pc3NpbmcgaW4gdGhlCj4ga2VybmVsIGRyaXZlciBzaW5j ZSBpdCB3YXMgY3JlYXRlZCwgc2hvdWxkIEkgYWRkIGEgQnVnRml4IGZvciB0aGUgZmlyc3QgY29t bWl0IG9mIHRoaXMgZHJpdmVyPwoKWWVzLCB0aGF0IGlzIG5vcm1hbC4gSWRlYWxseSB0aGUga2Vy bmVsIHNob3VsZCBub3QgZGVwZW5kIG9uIHUtYm9vdCwKYmVjYXVzZSBvZnRlbiBwZW9wbGUgd2Fu dCB0byB1c2Ugb3RoZXIgYm9vdGxvYWRlcnMsIGUuZy4gYmFyZWJveC4gWW91CnNob3VsZCBhbHNv IGNvbnNpZGVyIGtleGVjLCB3aGVyZSBvbmUga2VybmVsIGhhbmRzIG92ZXIgdG8gYW5vdGhlcgpr ZXJuZWwsIHdpdGhvdXQgdGhlIGJvb3Rsb2FkZXIgYmVpbmcgaW52b2x2ZWQuIEluIHN1Y2ggYSBz aXR1YXRpb24sCnlvdSBpZGVhbGx5IHdhbnQgdG8gYXNzZXJ0IGFuZCBkZWFzc2VydCB0aGUgcmVz ZXQganVzdCB0byBjbGVhbiBhd2F5CmFueSBzdGF0ZSB0aGUgb2xkIGtlcm5lbCBsZWZ0IGFyb3Vu ZC4KCkJ1dCBwbGVhc2UgZG8gbm90ZSwgdGhhdCB0aGUgcmVzZXQgaXMgb3B0aW9uYWwsIHNpbmNl IHlvdSBuZWVkIHRvIGJlCmFibGUgdG8gd29yayB3aXRoIG9sZCBEVCBibG9icyB3aGljaCBkb24n dCBoYXZlIHRoZSByZXNldCBwcm9wZXJ0eSBpbgp0aGVtLgoKCUFuZHJldwoKCgoKX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGludXgtYXJtLWtlcm5lbCBt YWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9s aXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtYXJtLWtlcm5lbAo=