From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: EDAC, dmc520:: add DMC520 EDAC driver From: James Morse Message-Id: Date: Tue, 5 Feb 2019 17:31:24 +0000 To: Borislav Petkov Cc: Rui Zhao , Sasha Levin , "mchehab@kernel.org" , "linux-edac@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linux Kernel , "will.deacon@arm.com" , "okaya@kernel.org" List-ID: SGkgQm9yaXMsCgpPbiAyMy8wMS8yMDE5IDE4OjQ2LCBCb3Jpc2xhdiBQZXRrb3Ygd3JvdGU6Cj4g T24gV2VkLCBKYW4gMjMsIDIwMTkgYXQgMDY6MzY6MjNQTSArMDAwMCwgSmFtZXMgTW9yc2Ugd3Jv dGU6Cj4+PiBXb3VsZCBsaWtlIHRvIGtub3cgd2hhdCdzIHRoZSBpbXBhY3QgaWYgdGhpcyBlcnJv ciBoYXBwZW5zLCBhbmQgaG93IHRvIGZpdCBpdAo+Pj4gd2l0aCBjdXJyZW50IHJlcG9ydGluZyBp biBFREFDIGNvcmUuCj4+Cj4+IEF0IGEgZ3Vlc3MgdGhlIGludGVycnVwdCB0cmlnZ2VycyB3aGVu IGxpbmtfZXJyX2NvdW50IGluY3JlYXNlcy4gKGxpbmtfZXJyIGhhcwo+PiBhbiBvdmVyZmxvdyBi aXQsIHNvIHRoZSBpbnRlcnJ1cHQgbXVzdCBiZSByZWxhdGVkIHRvIGEgY291bnRlcikuCj4+Cj4+ IElmIHdlIGNvdWxkIGFzc29jaWF0ZSBhIGxpbmsgd2l0aCBhIGxheWVyIGluIGVkYWMsIHdlIGNv dWxkIHJlcG9ydCBlcnJvcnMKPj4gYWdhaW5zdCB0aGF0IHBvaW50LiBCdXQgSSd2ZSBubyBpZGVh IGhvdyAnbGlua3MnIGNvcnJlc3BvbmQgd2l0aCAncmFua3MgYW5kIGJhbmtzJyEKCgo+IFdlbGws IEkgaGF2ZSBubyBjbHVlIHdoYXQga2luZCBvZiBsaW5rcyB5b3UgZ3V5cyBhcmUgdGFsa2luZyBi dXQgaWYKPiB0aG9zZSBhcmUgcGVyLWNoYW5jZSBjb2hlcmVudCBsaW5rcyB1c2VkIGJ5IGNvcmVz IHRvIGNvbW11bmljYXRlIGluIGEKPiBjb2hlcmVudCBmYWJyaWMsIG9yIGNvcmVzIGFuZCBkZXZp Y2VzLCB3aGF0IHdvdWxkIHNob3dpbmcgdGhvc2UgZXJyb3JzCj4gdG8gdGhlIHVzZXIgYnJpbmcg eWE/CgooSSBtZW50aW9uZWQgdGhpcyBiZWNhdXNlIGl0cyB0aGUgbmV4dCBpbnRlcnJ1cHQgaW4g dGhlIHJlZ2lzdGVyLCBpdHMgYW4gZXhhbXBsZQpvZiBzb21ldGhpbmcgdGhhdCBtYXkgYmUgYWRk ZWQgZm9yIGFub3RoZXIgcGxhdGZvcm0gaW4gdGhlIGZ1dHVyZSwgd2hpY2ggYWZmZWN0cwp0aGUg RFQgYW5kIHByb2JpbmcpCgoKPiBPciBhcmUgeWEgdGFsa2luZyBhYm91dCBkaWZmZXJlbnQga2lu ZHMgb2YgbGlua3M/CgouLi4gd2hhdGV2ZXIgdGhlIG1hbnVhbCBtZWFucyBieSAnbGluaycsIGdv b2QgcG9pbnQsIGl0IGNvdWxkIGJlIHRoZQppbnRlcmNvbm5lY3Qgc2lkZS4KCidhbGVydF9tb2Rl X25leHQnLCBpbiB0aGUgZmVhdHVyZSBjb250cm9sIHJlZ2lzdGVyIHRhbGtzIGFib3V0IERJTU0g dHJhaW5pbmcsCmFuZCBzYXlzICdkZmlfZXJyJyBpcyB0cmVhdGVkIGEgYSBsaW5rIGVycm9yLiBE RkkgaXMgZGVmaW5lZCBlYXJsaWVyIGFzIHRoZSAnRERSClBIWSBpbnRlcmZhY2UnLCBzbyB0aGVz ZSBtdXN0IGJlIGxpbmtzIGJldHdlZW4gdGhlIERNQzUyMCBhbmQgRERSLgoKCj4gSW4gYW55IGNh c2UsIHRoZSBmaXJzdCBxdWVzdGlvbiB0byBhc2sgd291bGQgYmUsIGNhbiBzb21lIGFnZW50IG9y IHRoZQo+IHVzZXIgZG8gc29tZXRoaW5nIHdpdGggdGhlIGluZm9ybWF0aW9uIHRoYXQgWCBvciBZ IGxpbmsgZXJyb3JzIGhhcHBlbmVkPwo+IAo+IElmIG5vdCwgdGhlbiB3aHkgYm90aGVyPwo+IElm IHllcywgdGhlbiB0aGF0J3MgYSBkaWZmZXJlbnQgc3RvcnkuCgpJIGFncmVlLiBTdXJlbHkgaWYg dGhlIERJTU1zIGFyZSBzb2NrZXRlZCBsaW5rLWVycm9ycyBhcmUgYW5vdGhlciByZWFzb24gdG8K cmVwbGFjZSB0aGUgRElNTS4KCkl0IGxvb2tzIGxpa2UgdGhpcyBkb2Vzbid0IG1hdHRlciBvbiBS dWkncyBwbGF0Zm9ybSwKCgpUaGFua3MsCgpKYW1lcwo= 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 E0619C282CB for ; Tue, 5 Feb 2019 17:31:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2B97217D6 for ; Tue, 5 Feb 2019 17:31:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730481AbfBERbc (ORCPT ); Tue, 5 Feb 2019 12:31:32 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:44082 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727097AbfBERbc (ORCPT ); Tue, 5 Feb 2019 12:31:32 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 54B07EBD; Tue, 5 Feb 2019 09:31:31 -0800 (PST) Received: from [10.1.196.105] (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A74253F557; Tue, 5 Feb 2019 09:31:26 -0800 (PST) Subject: Re: [PATCH] EDAC, dmc520:: add DMC520 EDAC driver To: Borislav Petkov Cc: Rui Zhao , Sasha Levin , "mchehab@kernel.org" , "linux-edac@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linux Kernel , "will.deacon@arm.com" , "okaya@kernel.org" References: <20190118162324.17123-1-sashal@kernel.org> <0866a996-49f7-1498-4653-20232bef2f46@arm.com> <7d404c61-a916-5d5e-35cc-0f6f016cd8a9@arm.com> <20190123184639.GD3227@zn.tnic> From: James Morse Message-ID: Date: Tue, 5 Feb 2019 17:31:24 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190123184639.GD3227@zn.tnic> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Boris, On 23/01/2019 18:46, Borislav Petkov wrote: > On Wed, Jan 23, 2019 at 06:36:23PM +0000, James Morse wrote: >>> Would like to know what's the impact if this error happens, and how to fit it >>> with current reporting in EDAC core. >> >> At a guess the interrupt triggers when link_err_count increases. (link_err has >> an overflow bit, so the interrupt must be related to a counter). >> >> If we could associate a link with a layer in edac, we could report errors >> against that point. But I've no idea how 'links' correspond with 'ranks and banks'! > Well, I have no clue what kind of links you guys are talking but if > those are per-chance coherent links used by cores to communicate in a > coherent fabric, or cores and devices, what would showing those errors > to the user bring ya? (I mentioned this because its the next interrupt in the register, its an example of something that may be added for another platform in the future, which affects the DT and probing) > Or are ya talking about different kinds of links? ... whatever the manual means by 'link', good point, it could be the interconnect side. 'alert_mode_next', in the feature control register talks about DIMM training, and says 'dfi_err' is treated a a link error. DFI is defined earlier as the 'DDR PHY interface', so these must be links between the DMC520 and DDR. > In any case, the first question to ask would be, can some agent or the > user do something with the information that X or Y link errors happened? > > If not, then why bother? > If yes, then that's a different story. I agree. Surely if the DIMMs are socketed link-errors are another reason to replace the DIMM. It looks like this doesn't matter on Rui's platform, Thanks, James