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 D9711C433EF for ; Wed, 4 May 2022 15:57:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352965AbiEDQAu (ORCPT ); Wed, 4 May 2022 12:00:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352962AbiEDQAs (ORCPT ); Wed, 4 May 2022 12:00:48 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9F9D4615A; Wed, 4 May 2022 08:57:08 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 641FE210E1; Wed, 4 May 2022 15:57:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1651679827; h=from:from:reply-to: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=Nu4FNczpZovRCMLybZ5k5rdDCEUYi3yOv4DX+sivCNc=; b=YaaUVhSRP5GfOdY2LJNhrw0zcyHIdbiTMz0zj9Uc7X0cg8wRTltA+1tJX8+n+pE3HmN/96 GCQ4MBEVKbCBpzNefZPdi8vvKmVmniACzN6LXAmRJGwENURN4ArHLM2iHP3MAqfwFoO41q WQJiMyj03IXIYJcUR850l7JEgifK4ZA= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id AF262132C4; Wed, 4 May 2022 15:57:06 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id GLt2KVKicmLWPAAAMHmgww (envelope-from ); Wed, 04 May 2022 15:57:06 +0000 From: Juergen Gross To: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-s390@vger.kernel.org, virtualization@lists.linux-foundation.org Cc: Juergen Gross , Arnd Bergmann , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , "Michael S. Tsirkin" , Jason Wang , Christoph Hellwig , Oleksandr Tyshchenko Subject: [PATCH v3 1/2] kernel: add platform_has() infrastructure Date: Wed, 4 May 2022 17:57:02 +0200 Message-Id: <20220504155703.13336-2-jgross@suse.com> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20220504155703.13336-1-jgross@suse.com> References: <20220504155703.13336-1-jgross@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arch@vger.kernel.org Add a simple infrastructure for setting, resetting and querying platform feature flags. Flags can be either global or architecture specific. Signed-off-by: Juergen Gross --- V2: - rename set/reset functions to platform_[set|clear]() (Boris Petkov, Heiko Carstens) - move function implementations to c file (Boris Petkov) --- MAINTAINERS | 8 ++++++++ include/asm-generic/Kbuild | 1 + include/asm-generic/platform-feature.h | 8 ++++++++ include/linux/platform-feature.h | 15 ++++++++++++++ kernel/Makefile | 2 +- kernel/platform-feature.c | 27 ++++++++++++++++++++++++++ 6 files changed, 60 insertions(+), 1 deletion(-) create mode 100644 include/asm-generic/platform-feature.h create mode 100644 include/linux/platform-feature.h create mode 100644 kernel/platform-feature.c diff --git a/MAINTAINERS b/MAINTAINERS index edc96cdb85e8..2749a88d75f2 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15657,6 +15657,14 @@ S: Maintained F: Documentation/devicetree/bindings/iio/chemical/plantower,pms7003.yaml F: drivers/iio/chemical/pms7003.c +PLATFORM FEATURE INFRASTRUCTURE +M: Juergen Gross +S: Maintained +F: arch/*/include/asm/platform-feature.h +F: include/asm-generic/platform-feature.h +F: include/linux/platform-feature.h +F: kernel/platform-feature.c + PLDMFW LIBRARY M: Jacob Keller S: Maintained diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild index 302506bbc2a4..8e47d483b524 100644 --- a/include/asm-generic/Kbuild +++ b/include/asm-generic/Kbuild @@ -44,6 +44,7 @@ mandatory-y += msi.h mandatory-y += pci.h mandatory-y += percpu.h mandatory-y += pgalloc.h +mandatory-y += platform-feature.h mandatory-y += preempt.h mandatory-y += rwonce.h mandatory-y += sections.h diff --git a/include/asm-generic/platform-feature.h b/include/asm-generic/platform-feature.h new file mode 100644 index 000000000000..4b0af3d51588 --- /dev/null +++ b/include/asm-generic/platform-feature.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_GENERIC_PLATFORM_FEATURE_H +#define _ASM_GENERIC_PLATFORM_FEATURE_H + +/* Number of arch specific feature flags. */ +#define PLATFORM_ARCH_FEAT_N 0 + +#endif /* _ASM_GENERIC_PLATFORM_FEATURE_H */ diff --git a/include/linux/platform-feature.h b/include/linux/platform-feature.h new file mode 100644 index 000000000000..6ed859928b97 --- /dev/null +++ b/include/linux/platform-feature.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _PLATFORM_FEATURE_H +#define _PLATFORM_FEATURE_H + +#include +#include + +/* The platform features are starting with the architecture specific ones. */ +#define PLATFORM_FEAT_N (0 + PLATFORM_ARCH_FEAT_N) + +void platform_set(unsigned int feature); +void platform_clear(unsigned int feature); +bool platform_has(unsigned int feature); + +#endif /* _PLATFORM_FEATURE_H */ diff --git a/kernel/Makefile b/kernel/Makefile index 847a82bfe0e3..2f412f80110d 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -7,7 +7,7 @@ obj-y = fork.o exec_domain.o panic.o \ cpu.o exit.o softirq.o resource.o \ sysctl.o capability.o ptrace.o user.o \ signal.o sys.o umh.o workqueue.o pid.o task_work.o \ - extable.o params.o \ + extable.o params.o platform-feature.o \ kthread.o sys_ni.o nsproxy.o \ notifier.o ksysfs.o cred.o reboot.o \ async.o range.o smpboot.o ucount.o regset.o diff --git a/kernel/platform-feature.c b/kernel/platform-feature.c new file mode 100644 index 000000000000..cb6a6c3e4fed --- /dev/null +++ b/kernel/platform-feature.c @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include + +#define PLATFORM_FEAT_ARRAY_SZ BITS_TO_LONGS(PLATFORM_FEAT_N) +static unsigned long __read_mostly platform_features[PLATFORM_FEAT_ARRAY_SZ]; + +void platform_set(unsigned int feature) +{ + set_bit(feature, platform_features); +} +EXPORT_SYMBOL_GPL(platform_set); + +void platform_clear(unsigned int feature) +{ + clear_bit(feature, platform_features); +} +EXPORT_SYMBOL_GPL(platform_clear); + +bool platform_has(unsigned int feature) +{ + return test_bit(feature, platform_features); +} +EXPORT_SYMBOL_GPL(platform_has); -- 2.35.3