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 0EDECC02192 for ; Fri, 7 Feb 2025 08:41:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Q3LyG1mkg7NlCAYeLHiZsZMLil8RCSZiCNMrxGuaTsk=; b=04mGM4baMXHuaMZG/G6EyGiRVK LwVVpF1ofI7kOCVE6ukTP+0H9F3Eud1jRTeOO7Ftekzq4YdpAzom4yDWusxYRTg5wDeSImPF+AD/V pEf2R1sFk+g2BGs5/JeB9HR9Vn8FoOq/3/K6wYuGC/BxNYWI0N+rmXZr+nIIV2DLozChENTU0puol I9Z50QOTrnOfamDOYdohk6K1OSjKPmrLlaeyrixTsa/f7rNI+XNonPjNJzeQ56doWNE3Xzat187Zs xXg77gK3QUHJTj3ReKHz+Nru1QJG7qFg5AjdCIAWTgsikk4uYjHBJ8hXGWKH0J7nYpJ8siIc1Ghxb gMLNIPPQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tgJv8-00000008rBi-3qDl; Fri, 07 Feb 2025 08:41:06 +0000 Received: from mx1.tq-group.com ([93.104.207.81]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tgJrB-00000008qHX-27mn for linux-arm-kernel@lists.infradead.org; Fri, 07 Feb 2025 08:37:02 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1738917422; x=1770453422; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Q3LyG1mkg7NlCAYeLHiZsZMLil8RCSZiCNMrxGuaTsk=; b=MRuHFURsE2qxh6iEm0oEdFq4VjWOfK1MjEN0W8C2yAHTAj7hFV1CRXA9 8+gLsaK6+7jR2c9WR1HwnlI6lWbO7P5RXKVJwwj4fX0mdVGaKd9qy2LOP tQ+n+7cidLXvoEJnlFpnCHT+u7rjqcuy/8TYHJcs/vQGwoXK3eJCvgNm3 FO3Sm2qYt6yjRvoxSvhQqftaTufqw5QVnBxJyqc1KVqzSaPbtGxxc+35g ReGZYamUiUIVG5M2LAJKp9P9o5cwKJ6cMVBvsxKYMD7nk8PrtmQnJWL/L Hp9NBOFzV/Z7krOTZ+x7foTHBc43Qb6Vyfdigq2NbnG01kQhpHVBSQY54 Q==; X-CSE-ConnectionGUID: vpSVzm22RyO5Zr0U+CasfA== X-CSE-MsgGUID: 3H5g9f8PSaa/MPkbu7lblQ== X-IronPort-AV: E=Sophos;i="6.13,266,1732575600"; d="scan'208";a="41636074" Received: from vmailcow01.tq-net.de ([10.150.86.48]) by mx1.tq-group.com with ESMTP; 07 Feb 2025 09:36:38 +0100 X-CheckPoint: {67A5C615-0-7A8FD441-CBCD789D} X-MAIL-CPID: 66C78CBF8FFC8EE94A2495468FCDC6F7_3 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 3C276168331; Fri, 7 Feb 2025 09:36:32 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ew.tq-group.com; s=dkim; t=1738917392; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Q3LyG1mkg7NlCAYeLHiZsZMLil8RCSZiCNMrxGuaTsk=; b=ML4qHaj/+G+iPMqG7hy85nGYawKwktErwhj0TGxUNBfGJktZS+6BlIGuBLvZOwd1JX5Tfm VKS19bWSBMEjY9WBG/CTIvWdVOS09LONWi3fKfe+5Tm96bB30WafxXrFTbt2J0RSUCh4yR cPg50xa1p378DJL4DXKIDvhu9wwt7EFEjfMBGa3Q/I6O63xislEILXtXObA89EzmyoBYXU JGTX5kUmTzV59i34mlZED/N2HL2uNmev1hQZIWKspdNa0dpvYfqxyIDTl2du4ia58Az9JC /cf5FxYX5wHf8CbUTf4gPN+0o01UgAlVb6qBsaQMajpn0e2CIrlJz2A2k++zAA== From: Alexander Stein To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Srinivas Kandagatla Cc: Alexander Stein , devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 02/10] nvmem: imx-ocotp: Support accessing controller for i.MX8M Date: Fri, 7 Feb 2025 09:36:07 +0100 Message-Id: <20250207083616.1442887-3-alexander.stein@ew.tq-group.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250207083616.1442887-1-alexander.stein@ew.tq-group.com> References: <20250207083616.1442887-1-alexander.stein@ew.tq-group.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250207_003701_843745_83B16A02 X-CRM114-Status: GOOD ( 19.39 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org i.MX8M OCOTP supports a specific peripheral or function being fused which means disabled, so - Introduce disable_fuse for a list of possible fused peripherals. - Iterate all nodes to check accessing permission. If not allowed to be accessed, detach the node Signed-off-by: Alexander Stein --- drivers/nvmem/Kconfig | 3 ++ drivers/nvmem/imx-ocotp.c | 74 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 76 insertions(+), 1 deletion(-) diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index 8671b7c974b93..ba5c928cab520 100644 --- a/drivers/nvmem/Kconfig +++ b/drivers/nvmem/Kconfig @@ -84,6 +84,9 @@ config NVMEM_IMX_OCOTP This driver can also be built as a module. If so, the module will be called nvmem-imx-ocotp. + If built as modules, any other driver relying on this working + as access controller also needs to be a module as well. + config NVMEM_IMX_OCOTP_ELE tristate "i.MX On-Chip OTP Controller support" depends on ARCH_MXC || COMPILE_TEST diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c index c5086a16450ac..b15cbdae66a7c 100644 --- a/drivers/nvmem/imx-ocotp.c +++ b/drivers/nvmem/imx-ocotp.c @@ -589,6 +589,74 @@ static void imx_ocotp_fixup_dt_cell_info(struct nvmem_device *nvmem, cell->read_post_process = imx_ocotp_cell_pp; } +static int imx_ocotp_check_access(struct ocotp_priv *priv, u32 addr, u32 bit) +{ + u32 mask, ret, val; + + mask = BIT(bit); + + ret = imx_ocotp_read(priv, addr, &val, sizeof(val)); + if (ret) + return ret; + + /* true means disabled */ + if (val & mask) + return -EACCES; + + return 0; +} + +static int imx_ocotp_grant_access(struct ocotp_priv *priv, struct device_node *parent) +{ + struct device *dev = priv->dev; + + for_each_available_child_of_node_scoped(parent, child) { + struct of_phandle_args args; + u32 idx = 0; + u32 addr; + u32 bit; + + while (!of_parse_phandle_with_args(child, "access-controllers", + "#access-controller-cells", + idx++, &args)) { + of_node_put(args.np); + if (args.np != dev->of_node) + continue; + + /* Only support one cell */ + if (args.args_count != 2) { + dev_err(dev, "wrong args count\n"); + continue; + } + + addr = args.args[0]; + bit = args.args[1]; + + dev_dbg(dev, "Checking node: %pOF disable fuse addr: %u, bit %u\n", child, addr, bit); + + if (imx_ocotp_check_access(priv, addr, bit)) { + of_detach_node(child); + dev_info(dev, "%pOF: disabled by fuse, device driver will not be probed\n", + child); + } + } + + imx_ocotp_grant_access(priv, child); + } + + return 0; +} + +static int imx_ocotp_access_control(struct ocotp_priv *priv) +{ + struct device_node *root __free(device_node) = of_find_node_by_path("/"); + + if (WARN_ON(!root)) + return -EINVAL; + + return imx_ocotp_grant_access(priv, root); +} + static int imx_ocotp_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -622,9 +690,13 @@ static int imx_ocotp_probe(struct platform_device *pdev) imx_ocotp_clr_err_if_set(priv); clk_disable_unprepare(priv->clk); + platform_set_drvdata(pdev, priv); + nvmem = devm_nvmem_register(dev, &imx_ocotp_nvmem_config); + if (IS_ERR(nvmem)) + return PTR_ERR(nvmem); - return PTR_ERR_OR_ZERO(nvmem); + return imx_ocotp_access_control(priv); } static struct platform_driver imx_ocotp_driver = { -- 2.34.1