From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.153.233]) (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 A051D35C190; Tue, 30 Jun 2026 09:24:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=68.232.153.233 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782811471; cv=none; b=vA/pBVzATmldknLk6dQ0yTYTLnCMeQh9JDcuTOaPmNlMvDX0uK58fycxOMtfokmgAEOSs+zVOMo5kMde8eXAzLE8pldLMiyF+9U8X6MgZ7DdKDiKLtwJe1uJH6KveoaulVj01W3Udnm/s3Aq7CBB9ih8hUBK5VwqI5/zvgrDxBM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782811471; c=relaxed/simple; bh=MAR7dBMvboAZsq8wqndsRj8+f2jQFua2iR0ewa1tL7c=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=QLYXA8ydn02ll+JfekAW5ZldInhOdRac5ToFw9QDR3RqiShz8/Br8x7OujOQa76YnyuA8HitXJOYMBlLis0H7PxR4UpOoPElQlaFM98XKHrsRqKvQBSrXtN9jg3h8xADFkPPR/0f93cl+/EnuhCRA9qNUpgohbcu0sOV/OM7oaM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com; spf=pass smtp.mailfrom=microchip.com; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b=RrTK5d2w; arc=none smtp.client-ip=68.232.153.233 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b="RrTK5d2w" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1782811469; x=1814347469; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=MAR7dBMvboAZsq8wqndsRj8+f2jQFua2iR0ewa1tL7c=; b=RrTK5d2w1AmWNuQWOzC/8ERb8OGF+W5kdYok63VMTqNiW1z/4FkbLstl BJdsJBdVGR1OECgzhl2vz1tVvAwWrGT2cahpJwRZ+1jjTTHkhjCL1/C6G RufZvmUY6UDYzmpEj8WtNEJj9abs1yUzKysSMhlmbbHU0RDxcSXEgnBTX MEIOqsXRJisSj5PvpTzpDHgSyZMjYtRFVtYEuNVgX/+ZeVuX8tHk2xuQm QyOtApNu2dG9JT6TXw3hjZz04e2YqL46azN0xWLBM79oB+d7wIIyGomCg OIplOm7YL9esnnZKz94oDIvncWMOyYdQx2v9bWNMOzH5zJDhRGyu38EeK g==; X-CSE-ConnectionGUID: h08U4A3ST1ap5TG9w0Nndw== X-CSE-MsgGUID: 854853ThQGG7lQfDPj9ddw== X-IronPort-AV: E=Sophos;i="6.24,233,1774335600"; d="scan'208";a="291266459" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa5.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jun 2026 02:24:27 -0700 Received: from chn-vm-ex02.mchp-main.com (10.10.87.72) by chn-vm-ex3.mchp-main.com (10.10.87.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.2.2562.43; Tue, 30 Jun 2026 02:24:26 -0700 Received: from che-ll-i67131.microchip.com (10.10.85.11) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server id 15.1.2507.58 via Frontend Transport; Tue, 30 Jun 2026 02:24:18 -0700 From: Manikandan Muralidharan To: , , , , , , , , , , , , , , , , , , , , , , CC: Manikandan Muralidharan Subject: [PATCH v4 0/7] Read MAC address from SST vendor specific SFDP region Date: Tue, 30 Jun 2026 14:53:59 +0530 Message-ID: <20260630092406.150587-1-manikandan.m@microchip.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain Some Microchip/SST QSPI flashes (e.g. the SST26VF064BEUI) are factory programmed with globally unique, write-protected EUI-48 and EUI-64 identifiers stored in a vendor-specific SFDP parameter table. On boards that have no on-board EEPROM (sama5d27_wlsom1, sama5d29 curiosity, sam9x75 curiosity) this is a reliable source for an Ethernet MAC address, instead of relying on a U-Boot-provided or random address. This v4 reworks the approach into a generic NVMEM framework with no vendor code in the SPI NOR core: - The SPI NOR core now exposes the entire SFDP as a generic read-only NVMEM device, rooted at a new "sfdp" child node of the flash. - A new NVMEM layout driver (drivers/nvmem/layouts/) locates the Microchip vendor parameter table at runtime and presents the EUI-48 as a "mac-address" cell. - Arbitrary parameters can be read with a standard fixed-layout (known offset) or with an nvmem-layout parser (location discovered at runtime). Changes in v4: - Rework per v3 review: remove the vendor-specific SFDP handling from the SPI NOR core; expose the whole SFDP as a generic read-only NVMEM device and move the EUI extraction into an nvmem-layout driver. - Introduce a new nvmem-layout driver to discover the vendor-table location at runtime; no offset hardcoded in the device tree. - Describe the SFDP via a dedicated "sfdp" subnode (compatible "jedec,sfdp"), which also resolves the v3 dtbs_check "Unevaluated properties ('nvmem-layout')" warning. - Reverse the stored EUI bytes into canonical MAC order. - Enable the layout in sama5_defconfig. Changes in v3: - 2/3 - add support to update the QSPI partition into 'fixed-partition' binding in sama5d27_wlsom1 - 3/3 - add nvmem-layout in qspi node for EUI48 MAC Address and nvmem cell properties for macb node in sama5d27_wlsom1 Changes in v2: - 1/3 - parse the SST vendor table, read and store the addresses into a resource - managed space. Register the addresses into NVMEM framework - 2/3 - add support to update the QSPI partition into 'fixed-partition' binding v3: https://lore.kernel.org/linux-arm-kernel/20250521070336.402202-1-manikandan.m@microchip.com/ Manikandan Muralidharan (7): dt-bindings: mtd: jedec,spi-nor: allow the SFDP to be exposed via NVMEM dt-bindings: nvmem: layouts: add Microchip/SST SFDP EUI layout mtd: spi-nor: sfdp: expose the SFDP as a read-only NVMEM device nvmem: layouts: add Microchip/SST SFDP EUI layout driver ARM: dts: microchip: sama5d27_wlsom1: use fixed-partitions for QSPI flash ARM: dts: microchip: sama5d27_wlsom1: read MAC address from QSPI SFDP ARM: configs: sama5: enable Microchip/SST SFDP EUI NVMEM layout .../bindings/mtd/jedec,spi-nor.yaml | 18 ++ .../layouts/microchip,sst26vf-sfdp-eui.yaml | 60 ++++++ .../bindings/nvmem/layouts/nvmem-layout.yaml | 1 + MAINTAINERS | 6 + .../dts/microchip/at91-sama5d27_wlsom1.dtsi | 61 +++--- .../dts/microchip/at91-sama5d27_wlsom1_ek.dts | 2 + arch/arm/configs/sama5_defconfig | 1 + drivers/mtd/spi-nor/core.c | 5 + drivers/mtd/spi-nor/core.h | 1 + drivers/mtd/spi-nor/sfdp.c | 83 ++++++++ drivers/nvmem/layouts/Kconfig | 10 + drivers/nvmem/layouts/Makefile | 1 + drivers/nvmem/layouts/sst26vf-sfdp-eui.c | 182 ++++++++++++++++++ 13 files changed, 409 insertions(+), 22 deletions(-) create mode 100644 Documentation/devicetree/bindings/nvmem/layouts/microchip,sst26vf-sfdp-eui.yaml create mode 100644 drivers/nvmem/layouts/sst26vf-sfdp-eui.c base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482 -- 2.43.0