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 0989FC433FE for ; Sun, 27 Feb 2022 11:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230308AbiB0L6i (ORCPT ); Sun, 27 Feb 2022 06:58:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38840 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230294AbiB0L6g (ORCPT ); Sun, 27 Feb 2022 06:58:36 -0500 Received: from wout5-smtp.messagingengine.com (wout5-smtp.messagingengine.com [64.147.123.21]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A6F61B786; Sun, 27 Feb 2022 03:57:58 -0800 (PST) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.west.internal (Postfix) with ESMTP id 313E03200DA8; Sun, 27 Feb 2022 06:57:57 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute3.internal (MEProxy); Sun, 27 Feb 2022 06:57:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=svenpeter.dev; h=cc:cc:content-transfer-encoding:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to; s=fm3; bh=LHnbTtvZh1F0Dh tswLT8iTo1M9auO3PUzzd56DEi4/0=; b=RrXS5VRdvbBrnsrwu8P2ZJUjQ56j1p L7u/Uz1rDrWawiUyjvdE8e+Z4YLYub5AoIcqvxfcMXMtw1OrgGhdgSpe+EYACb7d CgCLBVvdlbFA4ZVX9JGBFwH1xI694kNhdWaW/UPz5bkVf2Rjt9m1nhpemPpQAKP0 5mym2CIQ2aq8QHRwX/xb/Asqc0GcO2QONJMr1HhTsV/qtACQPnjo4iu5d3S9VXGK f/rLbLskbCXPZqnGoWXVz+4O14SS4a3Funpha+Guhk4OQk8YRH3PRJvFtHoJ5D0+ SnLLg69HH2LtgfqCXM4dOIPtB0J/22wsBjz+R5F9pEl4GmIsaYQxV1Sw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:sender:subject:subject:to:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=LHnbTt vZh1F0DhtswLT8iTo1M9auO3PUzzd56DEi4/0=; b=UuJXtkDYzzmDv3+PlvrF75 IMSF+7TIjjIQ2zGFSCAJDUBZQxFwofks4FSECuCpKl1vIEe5hdPtmTxC1/FoIaRj NLRbj/CNsNtM1nVSPkaCvOCS/z0F/HbgeGRKm2JTkXoC7UapkSpECtJRVEH5RZOq QPodUEULOaR8Td6jBH/BgqFQThktGkGbHX9hAOrqio36yQAWjU32pOcMfMpU9rJ1 AcvlQKlhPlU09mMtX4RlV4kry6GpExnibfiMCm6/jSDsUBesjydfsfcO772pj1Rp 2v4uS02Fjpw4+nHPdnadIHTeGyVtByvh/PF9hIX/uwiCx8r7cdQT67U2tOhv4iVw == X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrleekgdeffecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkofgjfhgggfestdekredtredttdenucfhrhhomhepufhvvghnucfr vghtvghruceoshhvvghnsehsvhgvnhhpvghtvghrrdguvghvqeenucggtffrrghtthgvrh hnpeetvdekteeluefffffhkeetteffgefggfevheeileeufedvtdeuffevveelhfefjeen ucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehsvhgvnh esshhvvghnphgvthgvrhdruggvvh X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sun, 27 Feb 2022 06:57:55 -0500 (EST) From: Sven Peter To: Srinivas Kandagatla , Rob Herring Cc: Sven Peter , Hector Martin , Alyssa Rosenzweig , Mark Kettenis , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] nvmem: Add Apple eFuse driver Date: Sun, 27 Feb 2022 12:57:43 +0100 Message-Id: <20220227115743.69059-2-sven@svenpeter.dev> X-Mailer: git-send-email 2.30.1 (Apple Git-130) In-Reply-To: <20220227115743.69059-1-sven@svenpeter.dev> References: <20220227115743.69059-1-sven@svenpeter.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Apple SoCs contain eFuses used to store factory-programmed data such as calibration values for the PCIe or the Type-C PHY. They are organized as 32bit values exposed as MMIO. Signed-off-by: Sven Peter --- MAINTAINERS | 1 + drivers/nvmem/Kconfig | 12 +++++++ drivers/nvmem/Makefile | 2 ++ drivers/nvmem/apple-efuses.c | 67 ++++++++++++++++++++++++++++++++++++ 4 files changed, 82 insertions(+) create mode 100644 drivers/nvmem/apple-efuses.c diff --git a/MAINTAINERS b/MAINTAINERS index 1bc57af09c80..031198aec108 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1781,6 +1781,7 @@ F: drivers/i2c/busses/i2c-pasemi-core.c F: drivers/i2c/busses/i2c-pasemi-platform.c F: drivers/irqchip/irq-apple-aic.c F: drivers/mailbox/apple-mailbox.c +F: drivers/nvmem/apple-efuses.c F: drivers/pinctrl/pinctrl-apple-gpio.c F: drivers/soc/apple/* F: drivers/watchdog/apple_wdt.c diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index da414617a54d..ef6a13c8a4d6 100644 --- a/drivers/nvmem/Kconfig +++ b/drivers/nvmem/Kconfig @@ -300,4 +300,16 @@ config NVMEM_BRCM_NVRAM This driver provides support for Broadcom's NVRAM that can be accessed using I/O mapping. +config NVMEM_APPLE_EFUSES + tristate "Apple eFuse support" + depends on ARCH_APPLE || COMPILE_TEST + default ARCH_APPLE + help + Say y here to enabled support for reading eFuses on Apple SoCs + such as the M1. These are e.g. used to store factory programmed + calibration data required for the PCIe or the USB-C PHY. + + This driver can also be built as a module. If so, the module will + be called nvmem-apple-efuses. + endif diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile index dcbbde35b6a8..1a8e54691d3e 100644 --- a/drivers/nvmem/Makefile +++ b/drivers/nvmem/Makefile @@ -61,3 +61,5 @@ obj-$(CONFIG_NVMEM_RMEM) += nvmem-rmem.o nvmem-rmem-y := rmem.o obj-$(CONFIG_NVMEM_BRCM_NVRAM) += nvmem_brcm_nvram.o nvmem_brcm_nvram-y := brcm_nvram.o +obj-$(CONFIG_NVMEM_APPLE_EFUSES) += nvmem-apple-efuses.o +nvmem-apple-efuses-y := apple-efuses.o diff --git a/drivers/nvmem/apple-efuses.c b/drivers/nvmem/apple-efuses.c new file mode 100644 index 000000000000..925fc0033b83 --- /dev/null +++ b/drivers/nvmem/apple-efuses.c @@ -0,0 +1,67 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Apple SoC eFuse driver + * + * Copyright (C) The Asahi Linux Contributors + */ + +#include +#include +#include +#include +#include + +static int apple_efuses_read(void *context, unsigned int offset, void *val, + size_t bytes) +{ + void __iomem *fuses = context; + u32 *dst = val; + + while (bytes >= sizeof(u32)) { + *dst++ = readl_relaxed(fuses + offset); + bytes -= sizeof(u32); + offset += sizeof(u32); + } + + return 0; +} + +static int apple_efuses_probe(struct platform_device *pdev) +{ + struct resource *res; + struct nvmem_config config = { + .dev = &pdev->dev, + .read_only = true, + .reg_read = apple_efuses_read, + .stride = sizeof(u32), + .word_size = sizeof(u32), + .name = "apple_efuses_nvmem", + .id = NVMEM_DEVID_AUTO, + }; + + config.priv = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(config.priv)) + return PTR_ERR(config.priv); + + config.size = resource_size(res); + + return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config)); +} + +static const struct of_device_id apple_efuses_of_match[] = { + { .compatible = "apple,efuses", }, + {} +}; + +static struct platform_driver apple_efuses_driver = { + .driver = { + .name = "apple_efuses", + .of_match_table = apple_efuses_of_match, + }, + .probe = apple_efuses_probe, +}; + +module_platform_driver(apple_efuses_driver); + +MODULE_AUTHOR("Sven Peter "); +MODULE_LICENSE("GPL"); -- 2.25.1