From mboxrd@z Thu Jan 1 00:00:00 1970 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 8877A283CAF; Wed, 8 Oct 2025 13:28:26 +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=1759930106; cv=none; b=YFbsSTrzce4Q/qR1iWj7tAhxcLNrne1ztpF71ceE46NIF7BxQq2RkGVnPWWSkTjR9vNOCRvl/jk8WToBL/iuPp1nnGRdrmOZkYNhmdGoHOiDUzCq6He3jUuyl6mgFqhU7tWE2FXRMoM3rhnqR54Yh+qZ18G1KnIM/+jEHTPg0gw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759930106; c=relaxed/simple; bh=3pzYmZsg41AQcq91tl/+v0TTgt/Rx1I3erEHNiUptHw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=gt+bz7YyC6zB910vUV/WAtnrupKw7Wd2FoWeLKJeLPGWcxK+oIun+6XM5XX9zTQZTzPJwzCBq02tXCTPT6IhjLyIpROUmSwhuDq58OLALgF6Djbqg6e1PPpI+Z7RnErzS74/v25x22POg+OJkyMUcXurXtCVUwbrWCudlDJvl1c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ALqSMpby; 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="ALqSMpby" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BAAE7C4CEF5; Wed, 8 Oct 2025 13:28:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1759930106; bh=3pzYmZsg41AQcq91tl/+v0TTgt/Rx1I3erEHNiUptHw=; h=From:To:Cc:Subject:Date:From; b=ALqSMpbyhOP/U2/Oba7VywE4t3mM6yESXdsSrrpLY8YjKp6mKpbHvMLMh0VSTh4Gl L5jEQ/fY28WB9CD+FLEjXXVBRWbikg56myQTW8uFGRbUluX6h/87QNoF/v1GsPCd5Y dui0SpY/S+OZClkcOfz6BnXyZEX6HEy9Wx8lIfrWiQtQSPAR1BGeeaUmV/lvDweDcA XVWQoHZCk0OLh1YuJUtCnOqWi3xl21AKNElSEqU9Vj/pLe7fY4P645Z3wzp/Fjbj5K 0yRIBe9yIuL2v8uqVYQBdOVaoOw08DcKGc/UQRJmHPMU/nRS6kN5nTMb5ZkkfRYC4E zjQSUr5lLbaqQ== From: "Aneesh Kumar K.V (Arm)" To: linux-coco@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Steven Price , Gavin Shan , Suzuki K Poulose , Jeremy Linton , Sami Mujawar , "Aneesh Kumar K.V (Arm)" Subject: [PATCH] coco: guest: arm64: Update ARM CCA guest driver Date: Wed, 8 Oct 2025 18:57:58 +0530 Message-ID: <20251008132758.784275-1-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Make preparatory updates to the ARM CCA guest driver: - Switch from using a platform device to a faux device (based on feedback in [1]) - Rename the device from `arm-cca-dev` to `arm-rsi-dev`, so that the host driver can register an equivalent `arm-rmi-dev` These changes are purely structural and introduce no new functionality. Subsequent patches will extend this driver to add guest device assignment support. [1] https://lore.kernel.org/all/2025073035-bulginess-rematch-b92e@gregkh Signed-off-by: Aneesh Kumar K.V (Arm) --- NOTE: This patch is sent early outside the patchseries to avoid userspace from depending on the presence of the newly introduced platform device. The platform device was added in v6.14-rc1. arch/arm64/include/asm/rsi.h | 2 +- arch/arm64/kernel/rsi.c | 15 ----- drivers/virt/coco/arm-cca-guest/Makefile | 3 + .../{arm-cca-guest.c => arm-cca.c} | 65 +++++++++++-------- 4 files changed, 41 insertions(+), 44 deletions(-) rename drivers/virt/coco/arm-cca-guest/{arm-cca-guest.c => arm-cca.c} (85%) diff --git a/arch/arm64/include/asm/rsi.h b/arch/arm64/include/asm/rsi.h index b42aeac05340..26ef6143562b 100644 --- a/arch/arm64/include/asm/rsi.h +++ b/arch/arm64/include/asm/rsi.h @@ -10,7 +10,7 @@ #include #include -#define RSI_PDEV_NAME "arm-cca-dev" +#define RSI_DEV_NAME "arm-rsi-dev" DECLARE_STATIC_KEY_FALSE(rsi_present); diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index ce4778141ec7..569ef08750e5 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -140,18 +140,3 @@ void __init arm64_rsi_init(void) static_branch_enable(&rsi_present); } - -static struct platform_device rsi_dev = { - .name = RSI_PDEV_NAME, - .id = PLATFORM_DEVID_NONE -}; - -static int __init arm64_create_dummy_rsi_dev(void) -{ - if (is_realm_world() && - platform_device_register(&rsi_dev)) - pr_err("failed to register rsi platform device\n"); - return 0; -} - -arch_initcall(arm64_create_dummy_rsi_dev) diff --git a/drivers/virt/coco/arm-cca-guest/Makefile b/drivers/virt/coco/arm-cca-guest/Makefile index 69eeba08e98a..609462ea9438 100644 --- a/drivers/virt/coco/arm-cca-guest/Makefile +++ b/drivers/virt/coco/arm-cca-guest/Makefile @@ -1,2 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only +# obj-$(CONFIG_ARM_CCA_GUEST) += arm-cca-guest.o + +arm-cca-guest-$(CONFIG_TSM) += arm-cca.o diff --git a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c b/drivers/virt/coco/arm-cca-guest/arm-cca.c similarity index 85% rename from drivers/virt/coco/arm-cca-guest/arm-cca-guest.c rename to drivers/virt/coco/arm-cca-guest/arm-cca.c index 0c9ea24a200c..89d9e7f8eb5d 100644 --- a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c +++ b/drivers/virt/coco/arm-cca-guest/arm-cca.c @@ -1,8 +1,9 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright (C) 2023 ARM Ltd. + * Copyright (C) 2025 ARM Ltd. */ +#include #include #include #include @@ -181,52 +182,60 @@ static int arm_cca_report_new(struct tsm_report *report, void *data) return ret; } -static const struct tsm_report_ops arm_cca_tsm_ops = { +static const struct tsm_report_ops arm_cca_tsm_report_ops = { .name = KBUILD_MODNAME, .report_new = arm_cca_report_new, }; -/** - * arm_cca_guest_init - Register with the Trusted Security Module (TSM) - * interface. - * - * Return: - * * %0 - Registered successfully with the TSM interface. - * * %-ENODEV - The execution context is not an Arm Realm. - * * %-EBUSY - Already registered. - */ -static int __init arm_cca_guest_init(void) +static void unregister_cca_tsm_report(void *data) +{ + tsm_report_unregister(&arm_cca_tsm_report_ops); +} + +static int cca_tsm_probe(struct faux_device *fdev) { int ret; if (!is_realm_world()) return -ENODEV; - ret = tsm_report_register(&arm_cca_tsm_ops, NULL); - if (ret < 0) + ret = tsm_report_register(&arm_cca_tsm_report_ops, NULL); + if (ret < 0) { pr_err("Error %d registering with TSM\n", ret); + return ret; + } + + ret = devm_add_action_or_reset(&fdev->dev, unregister_cca_tsm_report, NULL); + if (ret < 0) { + pr_err("Error %d registering devm action\n", ret); + unregister_cca_tsm_report(NULL); + return ret; + } return ret; } -module_init(arm_cca_guest_init); -/** - * arm_cca_guest_exit - unregister with the Trusted Security Module (TSM) - * interface. - */ -static void __exit arm_cca_guest_exit(void) +static struct faux_device *cca_tsm; + +static const struct faux_device_ops cca_device_ops = { + .probe = cca_tsm_probe, +}; + +static int __init cca_tsm_init(void) { - tsm_report_unregister(&arm_cca_tsm_ops); + cca_tsm = faux_device_create(RSI_DEV_NAME, NULL, &cca_device_ops); + if (!cca_tsm) + return -ENOMEM; + return 0; } -module_exit(arm_cca_guest_exit); +module_init(cca_tsm_init); -/* modalias, so userspace can autoload this module when RSI is available */ -static const struct platform_device_id arm_cca_match[] __maybe_unused = { - { RSI_PDEV_NAME, 0}, - { } -}; +static void __exit cca_tsm_exit(void) +{ + faux_device_destroy(cca_tsm); +} +module_exit(cca_tsm_exit); -MODULE_DEVICE_TABLE(platform, arm_cca_match); MODULE_AUTHOR("Sami Mujawar "); MODULE_DESCRIPTION("Arm CCA Guest TSM Driver"); MODULE_LICENSE("GPL"); -- 2.43.0