From patchwork Mon Sep 4 09:06:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13373624 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 lists.gnu.org (lists.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 393C6C83F2C for ; Mon, 4 Sep 2023 09:10:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qd5YO-0002Go-6O; Mon, 04 Sep 2023 05:07:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qd5YL-00027i-5W; Mon, 04 Sep 2023 05:07:25 -0400 Received: from mail.ozlabs.org ([2404:9400:2221:ea00::3] helo=gandalf.ozlabs.org) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qd5YI-0003oK-PJ; Mon, 04 Sep 2023 05:07:24 -0400 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4RfN7X2thsz4wy9; Mon, 4 Sep 2023 19:07:20 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4RfN7V45Jwz4wy1; Mon, 4 Sep 2023 19:07:18 +1000 (AEST) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-ppc@nongnu.org, qemu-devel@nongnu.org Cc: Daniel Henrique Barboza , Nicholas Piggin , =?utf-8?q?C=C3=A9dric_Le_Goater?= Subject: [PULL 17/35] hw/ppc: Always store the decrementer value Date: Mon, 4 Sep 2023 11:06:12 +0200 Message-ID: <20230904090630.725952-18-clg@kaod.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230904090630.725952-1-clg@kaod.org> References: <20230904090630.725952-1-clg@kaod.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2404:9400:2221:ea00::3; envelope-from=SRS0=kZzc=EU=kaod.org=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -39 X-Spam_score: -4.0 X-Spam_bar: ---- X-Spam_report: (-4.0 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@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-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Nicholas Piggin When writing a value to the decrementer that raises an exception, the irq is raised, but the value is not stored so the store doesn't appear to have changed the register when it is read again. Always store the write value to the register. Fixes: e81a982aa53 ("PPC: Clean up DECR implementation") Signed-off-by: Nicholas Piggin Signed-off-by: Cédric Le Goater --- hw/ppc/ppc.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c index fb4784793ce1..d9a1cfbf91fe 100644 --- a/hw/ppc/ppc.c +++ b/hw/ppc/ppc.c @@ -841,6 +841,16 @@ static void __cpu_ppc_store_decr(PowerPCCPU *cpu, uint64_t *nextp, return; } + /* + * Calculate the next decrementer event and set a timer. + * decr_next is in timebase units to keep rounding simple. Note it is + * not adjusted by tb_offset because if TB changes via tb_offset changing, + * decrementer does not change, so not directly comparable with TB. + */ + now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + next = ns_to_tb(tb_env->decr_freq, now) + value; + *nextp = next; /* nextp is in timebase units */ + /* * Going from 1 -> 0 or 0 -> -1 is the event to generate a DEC interrupt. * @@ -862,16 +872,6 @@ static void __cpu_ppc_store_decr(PowerPCCPU *cpu, uint64_t *nextp, (*lower_excp)(cpu); } - /* - * Calculate the next decrementer event and set a timer. - * decr_next is in timebase units to keep rounding simple. Note it is - * not adjusted by tb_offset because if TB changes via tb_offset changing, - * decrementer does not change, so not directly comparable with TB. - */ - now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); - next = ns_to_tb(tb_env->decr_freq, now) + value; - *nextp = next; - /* Adjust timer */ timer_mod(timer, tb_to_ns_round_up(tb_env->decr_freq, next)); }