From nobody Sat Oct 4 01:39:27 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E22D92FB61B; Thu, 21 Aug 2025 15:40:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755790805; cv=none; b=bHQ8iYO5VjRFJyWYam0vkPuTuyEzIoTR43WY7EcCEV6wIK/vB30dB17tvjslxAW6yteNwmd9TWwaVIds6vDDEgyQavOZx54ILv95xnpgGRhyGpC0pb8wp1LwHH/fmp/YvdrlSDDVuKe8kB4UXbl9cbiN4cPnsnvGjpXR4BuGOU8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755790805; c=relaxed/simple; bh=vklN4/w2hbW7rNLgTYVlAI33wbeeVkY8FZwbhVtsJVg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Sp74Bgm3zCIOhp8mVcmyj1niCfOAMC4J5iopCaNMUTRbyr2dHXZDF+exggj43UqfKRO7Ci6ASZNrLzCMWx7HGqq+NzWrhgKbbzVCC2LymM9gQhK5nW5WFjYgIk0Z2NzO7g8knyYhNag4IPB2YoUCdLnvlIyHx/FosbvvNxvMrE0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tAw+xFUd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tAw+xFUd" Received: by smtp.kernel.org (Postfix) with ESMTPS id 374A8C2BCC4; Thu, 21 Aug 2025 15:40:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755790804; bh=vklN4/w2hbW7rNLgTYVlAI33wbeeVkY8FZwbhVtsJVg=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=tAw+xFUduHWkahyOaAhbPExukBZjrLPXq92a1OoG0AUbsQgti7TToFv2d9ZOjC9nU MpUpwBPyeExSw0QHPHHmmcDGR/hY+bXq9KAud+ulRNdRQnY30mADGuz0DvTnMMP8q0 /Iy5DSPakV5HwaR9Gv1rrAMPFjhQRm54fBPfZEWlCUU1qnluL2tkSuvXNBSSD+TRr1 ljA2+qKNofgRHGlUzso4/rg9937OCqIiXF2Q/muCRN5DW7O+dn4j/O603tNrVz7vbZ GfrRWVe51j0ilOkrAxmyhr6KLNNxE+hslkkJVriFs9a138ljii+y7sIhTnDrVDzNWZ 3zcQL30PFMOtA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28668CA0FE7; Thu, 21 Aug 2025 15:40:04 +0000 (UTC) From: Sven Peter Date: Thu, 21 Aug 2025 15:39:12 +0000 Subject: [PATCH RFC 20/22] soc: apple: Add hardware tunable support Precedence: bulk X-Mailing-List: linux-kernel@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 Message-Id: <20250821-atcphy-6-17-v1-20-172beda182b8@kernel.org> References: <20250821-atcphy-6-17-v1-0-172beda182b8@kernel.org> In-Reply-To: <20250821-atcphy-6-17-v1-0-172beda182b8@kernel.org> To: Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Felipe Balbi , Janne Grunau , Alyssa Rosenzweig , Neal Gompa , Vinod Koul , Kishon Vijay Abraham I , Thinh Nguyen , Heikki Krogerus , Philipp Zabel Cc: linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-phy@lists.infradead.org, Sven Peter X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=6361; i=sven@kernel.org; h=from:subject:message-id; bh=vklN4/w2hbW7rNLgTYVlAI33wbeeVkY8FZwbhVtsJVg=; b=owGbwMvMwCHmIlirolUq95LxtFoSQ8Zy21PV4iZzXpfc0TPWYvT0/nIx9ueWn9s2MSiGzV+wq 3PZic03OkpYGMQ4GGTFFFm277c3ffLwjeDSTZfew8xhZQIZwsDFKQATKb7CyPCkcbqJ7JuLEkmz GQsYm1WZ/gfP4DiiZfVrhvfthdsfbv/J8OP35dRP5QF28fv/v5s9keVIj4O/1YYbfVMs/nf/tnu 9hAcA X-Developer-Key: i=sven@kernel.org; a=openpgp; fpr=A1E3E34A2B3C820DBC4955E5993B08092F131F93 X-Endpoint-Received: by B4 Relay for sven@kernel.org/default with auth_id=407 Various hardware, like the Type-C PHY or the Thunderbolt/USB4 NHI, present on Apple SoCs need machine-specific tunables passed from our bootloader m1n1 to the device tree. Add generic helpers so that we don't have to duplicate this across multiple drivers. Signed-off-by: Sven Peter --- drivers/soc/apple/Kconfig | 4 ++ drivers/soc/apple/Makefile | 3 ++ drivers/soc/apple/tunable.c | 77 +++++++++++++++++++++++++++++++++++= ++++ include/linux/soc/apple/tunable.h | 64 ++++++++++++++++++++++++++++++++ 4 files changed, 148 insertions(+) diff --git a/drivers/soc/apple/Kconfig b/drivers/soc/apple/Kconfig index 6388cbe1e56b5a9d90acad3ee2377ed6ac0d207d..f266b70fd9620cc940dc685f7eb= 2972c21a361df 100644 --- a/drivers/soc/apple/Kconfig +++ b/drivers/soc/apple/Kconfig @@ -41,6 +41,10 @@ config APPLE_SART =20 Say 'y' here if you have an Apple SoC. =20 +config APPLE_TUNABLE + tristate + depends on ARCH_APPLE || COMPILE_TEST + endmenu =20 endif diff --git a/drivers/soc/apple/Makefile b/drivers/soc/apple/Makefile index 4d9ab8f3037b7159771d8817fa507ba29f99ae10..0b85ab61aefe131349a67d0aa80= 204edd8e89925 100644 --- a/drivers/soc/apple/Makefile +++ b/drivers/soc/apple/Makefile @@ -8,3 +8,6 @@ apple-rtkit-y =3D rtkit.o rtkit-crashlog.o =20 obj-$(CONFIG_APPLE_SART) +=3D apple-sart.o apple-sart-y =3D sart.o + +obj-$(CONFIG_APPLE_TUNABLE) +=3D apple-tunable.o +apple-tunable-y =3D tunable.o diff --git a/drivers/soc/apple/tunable.c b/drivers/soc/apple/tunable.c new file mode 100644 index 0000000000000000000000000000000000000000..3d9d47b3861f6fea637a3c82f27= 0e5d321b1a48e --- /dev/null +++ b/drivers/soc/apple/tunable.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple Silicon hardware tunable support + * + * Each tunable is a list with each entry containing a offset into the MMIO + * region, a mask of bits to be cleared and a set of bits to be set. These + * tunables are passed along by the previous boot stages and vary from dev= ice + * to device such that they cannot be hardcoded in the individual drivers. + * + * Copyright (C) The Asahi Linux Contributors + */ + +#include +#include +#include +#include + +int devm_apple_parse_tunable(struct device *dev, struct device_node *np, + struct apple_tunable *tunable, const char *name) +{ + struct property *prop; + const __le32 *p =3D NULL; + int i; + + prop =3D of_find_property(np, name, NULL); + if (!prop) { + dev_err(dev, "tunable %s not found\n", name); + return -ENOENT; + } + + if (prop->length % (3 * sizeof(u32))) + return -EINVAL; + + tunable->sz =3D prop->length / (3 * sizeof(u32)); + tunable->values =3D devm_kcalloc(dev, tunable->sz, + sizeof(*tunable->values), GFP_KERNEL); + if (!tunable->values) { + tunable->sz =3D 0; + return -ENOMEM; + } + + for (i =3D 0; i < tunable->sz; ++i) { + p =3D of_prop_next_u32(prop, p, &tunable->values[i].offset); + p =3D of_prop_next_u32(prop, p, &tunable->values[i].mask); + p =3D of_prop_next_u32(prop, p, &tunable->values[i].value); + } + + return 0; +} +EXPORT_SYMBOL(devm_apple_parse_tunable); + +void devm_apple_free_tunable(struct device *dev, struct apple_tunable *tun= able) +{ + devm_kfree(dev, tunable->values); + tunable->sz =3D 0; +} +EXPORT_SYMBOL(devm_apple_free_tunable); + +void apple_apply_tunable(void __iomem *regs, struct apple_tunable *tunable) +{ + size_t i; + + for (i =3D 0; i < tunable->sz; ++i) { + u32 val, old_val; + + val =3D old_val =3D readl_relaxed(regs + tunable->values[i].offset); + val &=3D ~tunable->values[i].mask; + val |=3D tunable->values[i].value; + if (val !=3D old_val) + writel_relaxed(val, regs + tunable->values[i].offset); + } +} +EXPORT_SYMBOL(apple_apply_tunable); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_AUTHOR("Sven Peter "); +MODULE_DESCRIPTION("Apple Silicon hardware tunable support"); diff --git a/include/linux/soc/apple/tunable.h b/include/linux/soc/apple/tu= nable.h new file mode 100644 index 0000000000000000000000000000000000000000..4a149f0f210d0b4b9e17c213f04= 82e8fbe02355f --- /dev/null +++ b/include/linux/soc/apple/tunable.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-only OR MIT */ +/* + * Apple Silicon hardware tunable support + * + * Each tunable is a list with each entry containing a offset into the MMIO + * region, a mask of bits to be cleared and a set of bits to be set. These + * tunables are passed along by the previous boot stages and vary from dev= ice + * to device such that they cannot be hardcoded in the individual drivers. + * + * Copyright (C) The Asahi Linux Contributors + */ + +#ifndef _LINUX_SOC_APPLE_TUNABLE_H_ +#define _LINUX_SOC_APPLE_TUNABLE_H_ + +#include +#include + +/* + * Struct to store a Apple Silicon hardware tunable. + * + * sz: number of [offset, mask, value] tuples stored in values. + * values: array containing the hardware tunables. + */ +struct apple_tunable { + size_t sz; + struct { + u32 offset; + u32 mask; + u32 value; + } *values; +}; + +/* + * Parse an array of hardware tunables from the device tree. + * + * Return 0 on success, -ENOMEM if the allocation failed and -ENOENT if the + * tunable could not be found or was in an invalid format. + * + * dev: Device node used for devm_kzalloc internally. + * np: Device node which contains the tunable array. + * tunable: Pointer to where the parsed tunables will be stored. + * name: Name of the device tree property which contains the tunables. + */ +int devm_apple_parse_tunable(struct device *dev, struct device_node *np, + struct apple_tunable *tunable, const char *name); + +/* + * Apply a previously loaded hardware tunable. + * + * regs: MMIO to which the tunable will be applied. + * tunable: Pointer to the tunable. + */ +void apple_apply_tunable(void __iomem *regs, struct apple_tunable *tunable= ); + +/* + * Manually frees a previous allocated tunable. + * + * dev: Device node used for devm_apple_parse_tunable + * tunable: Tunable allocaated by devm_apple_parse_tunable + */ +void devm_apple_free_tunable(struct device *dev, struct apple_tunable *tun= able); + +#endif --=20 2.34.1