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 X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A01AC433E0 for ; Mon, 15 Mar 2021 12:14:16 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8B85B64E76 for ; Mon, 15 Mar 2021 12:14:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B85B64E76 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:MIME-Version:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:Cc:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=rv5VHdTBgHYtOl/C50RHBC4UBdslqtRlGeCUdwkdpDk=; b=HZMYnod479WL7QPwa13P4UJDMP qGaWxwsBXjQ/Ac3dWqImqzN+ebVKPQE1WUQT7d0OoR7kWBEY+rtb/FeFJ05Gh4DJ+kznC7JfqmegL vG2GoNbkqcvE71EU2goPNJ703S//H12vJzNMmhRKmsv+z/p3GWcz6LC2nom5Ypv1FT6aQA0KtHpn7 /LwkJj9kQ7WH3IyGaaYupc7Xs8rRKuF2aInEX0B0B/4+Rdmrrl+hU8fF8Oy2O/xNr21gmqBG3w7jt XHDqr+e3bNeZiElC8uEZ9lHl0plWc1YbLdOG88KkFNhcBsXSx0ruB9nsz2sgxp8coEWVyrSJ55mYY +svP/fXw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lLm52-00Fnk4-Of; Mon, 15 Mar 2021 12:12:17 +0000 Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lLlq8-00FjGf-NU for linux-arm-kernel@lists.infradead.org; Mon, 15 Mar 2021 11:57:00 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BBF02143D; Mon, 15 Mar 2021 04:56:50 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 84F403F792; Mon, 15 Mar 2021 04:56:49 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will@kernel.org, catalin.marinas@arm.com Cc: james.morse@arm.com, marcan@marcan.st, mark.rutland@arm.com, maz@kernel.org, tglx@linutronix.de Subject: [PATCHv3 6/6] arm64: irq: allow FIQs to be handled Date: Mon, 15 Mar 2021 11:56:29 +0000 Message-Id: <20210315115629.57191-7-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210315115629.57191-1-mark.rutland@arm.com> References: <20210315115629.57191-1-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210315_115654_004985_BB1572C1 X-CRM114-Status: GOOD ( 13.15 ) 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: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On contemporary platforms we don't use FIQ, and treat any stray FIQ as a fatal event. However, some platforms have an interrupt controller wired to FIQ, and need to handle FIQ as part of regular operation. So that we can support both cases dynamically, this patch updates the FIQ exception handling code to operate the same way as the IRQ handling code, with its own handle_arch_fiq handler. Where a root FIQ handler is not registered, an unexpected FIQ exception will trigger the default FIQ handler, which will panic() as today. Where a root FIQ handler is registered, handling of the FIQ is deferred to that handler. As el0_fiq_invalid_compat is supplanted by el0_fiq, the former is removed. For !CONFIG_COMPAT builds we never expect to take an exception from AArch32 EL0, so we keep the common el0_fiq_invalid handler. Signed-off-by: Mark Rutland Tested-by: Hector Martin Cc: Catalin Marinas Cc: James Morse Cc: Marc Zyngier Cc: Thomas Gleixner Cc: Will Deacon --- arch/arm64/include/asm/irq.h | 1 + arch/arm64/kernel/entry.S | 30 +++++++++++++++++++++--------- arch/arm64/kernel/irq.c | 16 ++++++++++++++++ 3 files changed, 38 insertions(+), 9 deletions(-) diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h index 8391c6f6f746..fac08e18bcd5 100644 --- a/arch/arm64/include/asm/irq.h +++ b/arch/arm64/include/asm/irq.h @@ -10,6 +10,7 @@ struct pt_regs; int set_handle_irq(void (*handle_irq)(struct pt_regs *)); #define set_handle_irq set_handle_irq +int set_handle_fiq(void (*handle_fiq)(struct pt_regs *)); static inline int nr_legacy_irqs(void) { diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index ce8d4dc416fb..a86f50de2c7b 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -588,18 +588,18 @@ SYM_CODE_START(vectors) kernel_ventry 1, sync // Synchronous EL1h kernel_ventry 1, irq // IRQ EL1h - kernel_ventry 1, fiq_invalid // FIQ EL1h + kernel_ventry 1, fiq // FIQ EL1h kernel_ventry 1, error // Error EL1h kernel_ventry 0, sync // Synchronous 64-bit EL0 kernel_ventry 0, irq // IRQ 64-bit EL0 - kernel_ventry 0, fiq_invalid // FIQ 64-bit EL0 + kernel_ventry 0, fiq // FIQ 64-bit EL0 kernel_ventry 0, error // Error 64-bit EL0 #ifdef CONFIG_COMPAT kernel_ventry 0, sync_compat, 32 // Synchronous 32-bit EL0 kernel_ventry 0, irq_compat, 32 // IRQ 32-bit EL0 - kernel_ventry 0, fiq_invalid_compat, 32 // FIQ 32-bit EL0 + kernel_ventry 0, fiq_compat, 32 // FIQ 32-bit EL0 kernel_ventry 0, error_compat, 32 // Error 32-bit EL0 #else kernel_ventry 0, sync_invalid, 32 // Synchronous 32-bit EL0 @@ -665,12 +665,6 @@ SYM_CODE_START_LOCAL(el0_error_invalid) inv_entry 0, BAD_ERROR SYM_CODE_END(el0_error_invalid) -#ifdef CONFIG_COMPAT -SYM_CODE_START_LOCAL(el0_fiq_invalid_compat) - inv_entry 0, BAD_FIQ, 32 -SYM_CODE_END(el0_fiq_invalid_compat) -#endif - SYM_CODE_START_LOCAL(el1_sync_invalid) inv_entry 1, BAD_SYNC SYM_CODE_END(el1_sync_invalid) @@ -705,6 +699,12 @@ SYM_CODE_START_LOCAL_NOALIGN(el1_irq) kernel_exit 1 SYM_CODE_END(el1_irq) +SYM_CODE_START_LOCAL_NOALIGN(el1_fiq) + kernel_entry 1 + el1_interrupt_handler handle_arch_fiq + kernel_exit 1 +SYM_CODE_END(el1_fiq) + /* * EL0 mode handlers. */ @@ -731,6 +731,11 @@ SYM_CODE_START_LOCAL_NOALIGN(el0_irq_compat) b el0_irq_naked SYM_CODE_END(el0_irq_compat) +SYM_CODE_START_LOCAL_NOALIGN(el0_fiq_compat) + kernel_entry 0, 32 + b el0_fiq_naked +SYM_CODE_END(el0_fiq_compat) + SYM_CODE_START_LOCAL_NOALIGN(el0_error_compat) kernel_entry 0, 32 b el0_error_naked @@ -745,6 +750,13 @@ el0_irq_naked: b ret_to_user SYM_CODE_END(el0_irq) +SYM_CODE_START_LOCAL_NOALIGN(el0_fiq) + kernel_entry 0 +el0_fiq_naked: + el0_interrupt_handler handle_arch_fiq + b ret_to_user +SYM_CODE_END(el0_fiq) + SYM_CODE_START_LOCAL(el1_error) kernel_entry 1 mrs x1, esr_el1 diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c index 2fe0b535de30..bda49430c9ea 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -76,7 +76,13 @@ static void default_handle_irq(struct pt_regs *regs) panic("IRQ taken without a root IRQ handler\n"); } +static void default_handle_fiq(struct pt_regs *regs) +{ + panic("FIQ taken without a root FIQ handler\n"); +} + void (*handle_arch_irq)(struct pt_regs *) __ro_after_init = default_handle_irq; +void (*handle_arch_fiq)(struct pt_regs *) __ro_after_init = default_handle_fiq; int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) { @@ -88,6 +94,16 @@ int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) return 0; } +int __init set_handle_fiq(void (*handle_fiq)(struct pt_regs *)) +{ + if (handle_arch_fiq != default_handle_fiq) + return -EBUSY; + + handle_arch_fiq = handle_fiq; + pr_info("Root FIQ handler: %ps\n", handle_fiq); + return 0; +} + void __init init_IRQ(void) { init_irq_stacks(); -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel