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 lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (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 A6E48F36C24 for ; Mon, 20 Apr 2026 06:50:20 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wEiSL-0000H7-AU; Mon, 20 Apr 2026 02:50:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wEiS2-00008M-It for qemu-arm@nongnu.org; Mon, 20 Apr 2026 02:49:52 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wEiRz-0008K9-Gh for qemu-arm@nongnu.org; Mon, 20 Apr 2026 02:49:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1776667781; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=GU2deRWbajSFRwqWRixl/uXMDf5uGjjmU+yTI3sgtz8=; b=E7uojFnGKcPoEXnb/PQwDhlHbT8S6RU07mk352S4w8B4REkVFWq3SEZ+CotuDNQbFa5Lr1 aKzADwVCBhRDjDrRZRY0bpYXBz/so/p8WYDtia8QSuA15v3EuJ6sMwlN1ZHXuIt0V5Uf4J iw79p8QNGHgNBtXuW86ol31FURESzN0= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-587-lHwC9x6xNX6N-3-KKsG64w-1; Mon, 20 Apr 2026 02:49:37 -0400 X-MC-Unique: lHwC9x6xNX6N-3-KKsG64w-1 X-Mimecast-MFC-AGG-ID: lHwC9x6xNX6N-3-KKsG64w_1776667776 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8F4EE195608D; Mon, 20 Apr 2026 06:49:36 +0000 (UTC) Received: from thuth-p1g4.redhat.com (unknown [10.44.49.13]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 240B01800906; Mon, 20 Apr 2026 06:49:34 +0000 (UTC) From: Thomas Huth To: Peter Maydell , qemu-arm@nongnu.org Cc: qemu-devel@nongnu.org Subject: [PATCH] hw/arm: Remove hw_error() for the unimplemented CM_LMBUSCNT register Date: Mon, 20 Apr 2026 08:49:33 +0200 Message-ID: <20260420064933.64765-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Mimecast-MFC-PROC-ID: 9jAiQdz7kG0ZxzXdHlZLRmdfhF6sfW0yF-NanaPI8HU_1776667776 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Received-SPF: pass client-ip=170.10.129.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org From: Thomas Huth When writing to this register, QEMU currently aborts: $ echo "readl 0x10000018" | ./qemu-system-arm -audiodev none,id=snd0 \ -M integratorcp,accel=qtest,audiodev=snd0 -display none -qtest stdio [I 0.000000] OPENED [R +0.001907] readl 0x10000018 qemu: hardware error: integratorcm_read: CM_LMBUSCNT [...] Aborted (core dumped) This is bad, a guest should ideally never be able to kill QEMU like this. Now, according to the "Intergrator/CP User Guide" from: https://developer.arm.com/documentation/dui0159/b/porting-integrator-ap-and-im-pd1/registers "The Integrator/AP CM_LMBUSCNT has been removed." That means this register does not seem to be implemented on real CP boards at all, only for older AP boards. Thus it should be fine if we simply ignore this register in QEMU and handle it like all other unimplemented registers in the "default" handler of the case statement. Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3407 Signed-off-by: Thomas Huth --- hw/arm/integratorcp.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/hw/arm/integratorcp.c b/hw/arm/integratorcp.c index 0bf519b6bb8..28d478eb52b 100644 --- a/hw/arm/integratorcp.c +++ b/hw/arm/integratorcp.c @@ -107,9 +107,6 @@ static uint64_t integratorcm_read(void *opaque, hwaddr offset, } else { return s->cm_lock; } - case 6: /* CM_LMBUSCNT */ - /* ??? High frequency timer. */ - hw_error("integratorcm_read: CM_LMBUSCNT"); case 7: /* CM_AUXOSC */ return s->cm_auxosc; case 8: /* CM_SDRAM */ -- 2.53.0