From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 11C84378814; Fri, 3 Jul 2026 10:10:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.84.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783073444; cv=none; b=DptdwG9czl16GYm+zBW9CCVM1DYLeuQXrJyJ3ZxBxbNbqs3eNOEb0GO77NtRM/X8BQD7fhSmz5XXqv+CLGnFW4o2Qx1J8vcGRtb4C5Q+uhsBCzob0NImZXU+VSttxmHHGiMoQJPvm/rkqHCv64VegxRCYLdOJN2fV8hkzqFRwQA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783073444; c=relaxed/simple; bh=KUxpJqYYa0VhNofPWE55WEfT0pzSsC+tc3Iw1yJfJ80=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=cgalOGqzCGKPhRoVCRyHsEU5fu9btq6lQjbp01IAqDV4LJ2ppOONGVd5unruShzenVimrxwT11TAtEbCfnxbCFyOvirK5wbivl/uYrkGRzXnlrFtzNwlPYO8alJ+kE1lpTpyXmTogq5xcEd0ppTTt0kC4F+4X8k4+HLuq08IBoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=HKxugvqm; arc=none smtp.client-ip=185.246.84.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="HKxugvqm" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 7F4141A0DFC; Fri, 3 Jul 2026 10:10:40 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 50ABA60300; Fri, 3 Jul 2026 10:10:40 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id EAB20104C8399; Fri, 3 Jul 2026 12:10:32 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1783073438; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=KUxpJqYYa0VhNofPWE55WEfT0pzSsC+tc3Iw1yJfJ80=; b=HKxugvqmlXpYp00MdUMi8LdjB/ut+8I3zFW6xoA9fpxouy34H7l4QeEH1BXYeBOE7FxOE9 NjQNxmrt6ulvJwxDl30gHKLWJVYbXabaScEloreVGrP+rikqz0/W84cCWMSgkEV6pEPH35 YSkiOVtvZQmbC5WBMXXMIgbrS71E0PZqMzeP+NCrWcFcX93tadIRVjAQ8A9tfIXM1jxKaI SuX6hqE52+3qO6W2bu5QjqYnXPsI0GwvUwtlbNS6AaqWB2b7Uy3ZgKjnQYUoT9jbq9quM1 lf/0rDB21QVeASXPQ/PTNk8FNmD5by4w2OLHa48KLXakvZE970v99pA5YSpuJg== From: Miquel Raynal To: Rob Herring Cc: Manikandan.M@microchip.com, krzk@kernel.org, pratyush@kernel.org, mwalle@kernel.org, takahiro.kuwano@infineon.com, richard@nod.at, vigneshr@ti.com, krzk+dt@kernel.org, conor+dt@kernel.org, srini@kernel.org, Nicolas.Ferre@microchip.com, alexandre.belloni@bootlin.com, claudiu.beznea@tuxon.dev, linux@armlinux.org.uk, richardcochran@gmail.com, linusw@kernel.org, arnd@arndb.de, michael@walle.cc, linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org Subject: Re: [PATCH v4 1/7] dt-bindings: mtd: jedec,spi-nor: allow the SFDP to be exposed via NVMEM In-Reply-To: <20260702163723.GA227454-robh@kernel.org> (Rob Herring's message of "Thu, 2 Jul 2026 11:37:23 -0500") References: <20260630092406.150587-1-manikandan.m@microchip.com> <20260630092406.150587-2-manikandan.m@microchip.com> <20260702-utopian-termite-of-perfection-f1f3ec@quoll> <860213fd-6a4b-42d4-a8f7-7308e070f09e@microchip.com> <20260702163723.GA227454-robh@kernel.org> User-Agent: mu4e 1.12.7; emacs 30.2 Date: Fri, 03 Jul 2026 12:10:32 +0200 Message-ID: <8733y0penb.fsf@bootlin.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 On 02/07/2026 at 11:37:23 -05, Rob Herring wrote: > On Thu, Jul 02, 2026 at 06:55:15AM +0000, Manikandan.M@microchip.com wrot= e: >> Hi Krzysztof, >>=20 >> On 7/2/26 11:46 AM, Krzysztof Kozlowski wrote: >> > EXTERNAL EMAIL: Do not click links or open attachments unless you know= the content is safe >> >=20 >> > On Tue, Jun 30, 2026 at 02:54:00PM +0530, Manikandan Muralidharan wrot= e: >> >> Add an optional "sfdp" child node (compatible "jedec,sfdp") that >> >> describes the SFDP as a read-only NVMEM provider via nvmem.yaml, so i= ts >> >=20 >> > What is SFDP? >> >=20 >> SFDP is the Serial Flash Discoverable Parameters -- a JEDEC-standardised >> (JESD216) read-only parameter table present in most SPI NOR flashes, the= =20 >> table contents provide basic information about the flash. There are=20 >> standard tables which are specified by the JEDEC standard and there are= =20 >> vendor tables. > > Is SFDP present or not discoverable? Or we have a table of discoverable=20 > parameters that itself is not discoverable. SFDP is almost always there. I don't think there are any non SFDP chips manufactured today (?). The thing is, even if we don't need to define it in DT, we might need to point to it in order to extract eg. a unique ID or a MAC address through the NVMEM interface. SFDP is split into several sub-tables, the first one is mandatory, but then there are optional tables which can be discovered dynamically. Thanks, Miqu=C3=A8l 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 D79D0C43458 for ; Fri, 3 Jul 2026 10:10:52 +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:MIME-Version:Message-ID:Date:References :In-Reply-To:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XgjiFciiGss5XhdT4mLfVbLLlMkHvJDm43oeUm13b0g=; b=el3znifoBGXbBh UiHKGfpnLB4m9uHfs5BMivpkkuzxyNseIMliSJXazeWu4mmENGPzz24Q6beJuA3fx4/mkQplZv8Wt UmL2cG4qTo41JjzeESJ1Du7fnqaZ32t/3/W00CNwsf+jQCLGtobwoclJwJDM2hM5ROL+4Wn6GFyrI SVKibCckvHLDyxwwovBHmmvX9Ncpwm4MJaUQCQOJF9gABXsw8Q/uDLMxPTTq6x7JMQof7W1QhN2m2 xyGoujPoAoG0EvORnjSgL9WNhJc3i8IfjE00/0ckytwfSFXDBEMMQUUy82XmwjWq6Nz+rbNKHW5cV i2O4UxrBOtpkxAkmHUmw==; 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bh=KUxpJqYYa0VhNofPWE55WEfT0pzSsC+tc3Iw1yJfJ80=; b=HKxugvqmlXpYp00MdUMi8LdjB/ut+8I3zFW6xoA9fpxouy34H7l4QeEH1BXYeBOE7FxOE9 NjQNxmrt6ulvJwxDl30gHKLWJVYbXabaScEloreVGrP+rikqz0/W84cCWMSgkEV6pEPH35 YSkiOVtvZQmbC5WBMXXMIgbrS71E0PZqMzeP+NCrWcFcX93tadIRVjAQ8A9tfIXM1jxKaI SuX6hqE52+3qO6W2bu5QjqYnXPsI0GwvUwtlbNS6AaqWB2b7Uy3ZgKjnQYUoT9jbq9quM1 lf/0rDB21QVeASXPQ/PTNk8FNmD5by4w2OLHa48KLXakvZE970v99pA5YSpuJg== From: Miquel Raynal To: Rob Herring Cc: Manikandan.M@microchip.com, krzk@kernel.org, pratyush@kernel.org, mwalle@kernel.org, takahiro.kuwano@infineon.com, richard@nod.at, vigneshr@ti.com, krzk+dt@kernel.org, conor+dt@kernel.org, srini@kernel.org, Nicolas.Ferre@microchip.com, alexandre.belloni@bootlin.com, claudiu.beznea@tuxon.dev, linux@armlinux.org.uk, richardcochran@gmail.com, linusw@kernel.org, arnd@arndb.de, michael@walle.cc, linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org Subject: Re: [PATCH v4 1/7] dt-bindings: mtd: jedec,spi-nor: allow the SFDP to be exposed via NVMEM In-Reply-To: <20260702163723.GA227454-robh@kernel.org> (Rob Herring's message of "Thu, 2 Jul 2026 11:37:23 -0500") References: <20260630092406.150587-1-manikandan.m@microchip.com> <20260630092406.150587-2-manikandan.m@microchip.com> <20260702-utopian-termite-of-perfection-f1f3ec@quoll> <860213fd-6a4b-42d4-a8f7-7308e070f09e@microchip.com> <20260702163723.GA227454-robh@kernel.org> User-Agent: mu4e 1.12.7; emacs 30.2 Date: Fri, 03 Jul 2026 12:10:32 +0200 Message-ID: <8733y0penb.fsf@bootlin.com> MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260703_031043_613249_3D464F1A X-CRM114-Status: GOOD ( 13.16 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org T24gMDIvMDcvMjAyNiBhdCAxMTozNzoyMyAtMDUsIFJvYiBIZXJyaW5nIDxyb2JoQGtlcm5lbC5v cmc+IHdyb3RlOgoKPiBPbiBUaHUsIEp1bCAwMiwgMjAyNiBhdCAwNjo1NToxNUFNICswMDAwLCBN YW5pa2FuZGFuLk1AbWljcm9jaGlwLmNvbSB3cm90ZToKPj4gSGkgS3J6eXN6dG9mLAo+PiAKPj4g T24gNy8yLzI2IDExOjQ2IEFNLCBLcnp5c3p0b2YgS296bG93c2tpIHdyb3RlOgo+PiA+IEVYVEVS TkFMIEVNQUlMOiBEbyBub3QgY2xpY2sgbGlua3Mgb3Igb3BlbiBhdHRhY2htZW50cyB1bmxlc3Mg eW91IGtub3cgdGhlIGNvbnRlbnQgaXMgc2FmZQo+PiA+IAo+PiA+IE9uIFR1ZSwgSnVuIDMwLCAy MDI2IGF0IDAyOjU0OjAwUE0gKzA1MzAsIE1hbmlrYW5kYW4gTXVyYWxpZGhhcmFuIHdyb3RlOgo+ PiA+PiBBZGQgYW4gb3B0aW9uYWwgInNmZHAiIGNoaWxkIG5vZGUgKGNvbXBhdGlibGUgImplZGVj LHNmZHAiKSB0aGF0Cj4+ID4+IGRlc2NyaWJlcyB0aGUgU0ZEUCBhcyBhIHJlYWQtb25seSBOVk1F TSBwcm92aWRlciB2aWEgbnZtZW0ueWFtbCwgc28gaXRzCj4+ID4gCj4+ID4gV2hhdCBpcyBTRkRQ Pwo+PiA+IAo+PiBTRkRQIGlzIHRoZSBTZXJpYWwgRmxhc2ggRGlzY292ZXJhYmxlIFBhcmFtZXRl cnMgLS0gYSBKRURFQy1zdGFuZGFyZGlzZWQKPj4gKEpFU0QyMTYpIHJlYWQtb25seSBwYXJhbWV0 ZXIgdGFibGUgcHJlc2VudCBpbiBtb3N0IFNQSSBOT1IgZmxhc2hlcywgdGhlIAo+PiB0YWJsZSBj b250ZW50cyBwcm92aWRlIGJhc2ljIGluZm9ybWF0aW9uIGFib3V0IHRoZSBmbGFzaC4gVGhlcmUg YXJlIAo+PiBzdGFuZGFyZCB0YWJsZXMgd2hpY2ggYXJlIHNwZWNpZmllZCBieSB0aGUgSkVERUMg c3RhbmRhcmQgYW5kIHRoZXJlIGFyZSAKPj4gdmVuZG9yIHRhYmxlcy4KPgo+IElzIFNGRFAgcHJl c2VudCBvciBub3QgZGlzY292ZXJhYmxlPyBPciB3ZSBoYXZlIGEgdGFibGUgb2YgZGlzY292ZXJh YmxlIAo+IHBhcmFtZXRlcnMgdGhhdCBpdHNlbGYgaXMgbm90IGRpc2NvdmVyYWJsZS4KClNGRFAg aXMgYWxtb3N0IGFsd2F5cyB0aGVyZS4gSSBkb24ndCB0aGluayB0aGVyZSBhcmUgYW55IG5vbiBT RkRQIGNoaXBzCm1hbnVmYWN0dXJlZCB0b2RheSAoPykuIFRoZSB0aGluZyBpcywgZXZlbiBpZiB3 ZSBkb24ndCBuZWVkIHRvIGRlZmluZSBpdAppbiBEVCwgd2UgbWlnaHQgbmVlZCB0byBwb2ludCB0 byBpdCBpbiBvcmRlciB0byBleHRyYWN0IGVnLiBhIHVuaXF1ZSBJRApvciBhIE1BQyBhZGRyZXNz IHRocm91Z2ggdGhlIE5WTUVNIGludGVyZmFjZS4KClNGRFAgaXMgc3BsaXQgaW50byBzZXZlcmFs IHN1Yi10YWJsZXMsIHRoZSBmaXJzdCBvbmUgaXMgbWFuZGF0b3J5LCBidXQKdGhlbiB0aGVyZSBh cmUgb3B0aW9uYWwgdGFibGVzIHdoaWNoIGNhbiBiZSBkaXNjb3ZlcmVkIGR5bmFtaWNhbGx5LgoK VGhhbmtzLApNaXF1w6hsCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KTGludXggTVREIGRpc2N1c3Npb24gbWFpbGluZyBsaXN0Cmh0dHA6Ly9s aXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtbXRkLwo=