From patchwork Fri Nov 19 18:22:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Henrique Barboza X-Patchwork-Id: 12629349 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4EFD9C433F5 for ; Fri, 19 Nov 2021 18:29:25 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D4EDC61A58 for ; Fri, 19 Nov 2021 18:29:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D4EDC61A58 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:54800 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mo8dX-0005a0-Sv for qemu-devel@archiver.kernel.org; Fri, 19 Nov 2021 13:29:23 -0500 Received: from eggs.gnu.org ([209.51.188.92]:37616) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mo8XV-0004OM-3C; Fri, 19 Nov 2021 13:23:09 -0500 Received: from [2607:f8b0:4864:20::a35] (port=39677 helo=mail-vk1-xa35.google.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mo8XR-0001qH-Pw; Fri, 19 Nov 2021 13:23:08 -0500 Received: by mail-vk1-xa35.google.com with SMTP id 84so6399303vkc.6; Fri, 19 Nov 2021 10:23:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=wEhzjJ2tChIizKtHFKzSMHPFIqsyie4TVEusXUHYHu0=; b=JrkG/it9EeM7frjETcmcPhEfespsTaCtd/uL09MJ/74gxkpz2QqcNNYwPEquH0CjyG XLoaCiVckCDPVlo8A3mTZWAHHl3qT+Hj8VjzRJoWG5BSCuU17Ap3sNyqOe7uEFxJ0vkA yZoWW8OewjYiryvCk5i2K2t7czBY+slHQFFgWT+aGRP0eogO1zHJHfvy5e8CWjwm+8t3 xzbiuj688mRweqqbJbg0VVqwIEHnDF7rF2hxKipCZ702UZnfVxs51ECqsi5GFb2HVqt2 BWkJ3ERjze4GJu/RrOwzPmPk3vlbx73b2NvIE3x4Obmlw4IjjGWESKWl2ahLTifY7d6W bx9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=wEhzjJ2tChIizKtHFKzSMHPFIqsyie4TVEusXUHYHu0=; b=zWGHyzzz6uIseS4hgmaoC8C9kbwj0L/Pg+ZrLTcbAwJXm0qa+D3s3it4PPiQh3NEUv hJp7HEAWuTxlmkQAsSXBmy+UUTRKcKHIWWvg3DU3gEQak4zCbbK6M7+GRdKUYlMt3RSo AkYkiEoUP/jIW0a7JAThA7IHEeUM1g1oyIC389gCFGlAO36MEI9rMr7zIslKBh1IsfBv hGvSol8853s9z3s3UBtWnWMFpV+B1uhKeRnv5yzruEc86MIybH3luhlVFr36GGh8cA12 mAgRzn/piBV5zehs0JD6q9eXmHg81oiPj0E2Teu/0r74lTEZ/2qCD+ooli2Pte63HZIM dW3g== X-Gm-Message-State: AOAM532vCghxexeEa7fV6gey5r8voOfXhb44ZNhlkgbX8bpjEGpFkQMK V0H8c5i6PfuGHeOhmixJL9OGJ8sh1z6hrA== X-Google-Smtp-Source: ABdhPJzclwEFG9ZqibFgs558cyZTbCUsuOyYg3NTI5kpEaNspt4MHciqXXbG4tFFI6QXnlVaDuJb8g== X-Received: by 2002:a05:6122:214e:: with SMTP id m14mr97974972vkd.19.1637346181109; Fri, 19 Nov 2021 10:23:01 -0800 (PST) Received: from rekt.ibmuc.com ([152.250.208.89]) by smtp.gmail.com with ESMTPSA id x142sm339871vsx.15.2021.11.19.10.22.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Nov 2021 10:23:00 -0800 (PST) From: Daniel Henrique Barboza To: qemu-devel@nongnu.org Subject: [PATCH for-7.0 v7 10/10] target/ppc/excp_helper.c: EBB handling adjustments Date: Fri, 19 Nov 2021 15:22:16 -0300 Message-Id: <20211119182216.628676-11-danielhb413@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211119182216.628676-1-danielhb413@gmail.com> References: <20211119182216.628676-1-danielhb413@gmail.com> MIME-Version: 1.0 X-Host-Lookup-Failed: Reverse DNS lookup failed for 2607:f8b0:4864:20::a35 (failed) Received-SPF: pass client-ip=2607:f8b0:4864:20::a35; envelope-from=danielhb413@gmail.com; helo=mail-vk1-xa35.google.com X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_ENVFROM_END_DIGIT=0.25, FREEMAIL_FROM=0.001, PDS_HP_HELO_NORDNS=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no 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: , Cc: richard.henderson@linaro.org, Daniel Henrique Barboza , qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The current logic is only considering event-based exceptions triggered by the performance monitor. This is true now, but we might want to add support for external event-based exceptions in the future. Let's make it a bit easier to do so by adding the bit logic that would happen in case we were dealing with an external event-based exception. While we're at it, add a few comments explaining why we're setting and clearing BESCR bits. Signed-off-by: Daniel Henrique Barboza --- target/ppc/excp_helper.c | 45 ++++++++++++++++++++++++++++++++++------ 1 file changed, 39 insertions(+), 6 deletions(-) diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c index a26d266fe6..42e2fee9c8 100644 --- a/target/ppc/excp_helper.c +++ b/target/ppc/excp_helper.c @@ -801,14 +801,47 @@ static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp) break; case POWERPC_EXCP_EBB: /* Event-based branch exception */ if ((env->spr[SPR_FSCR] & (1ull << FSCR_EBB)) && - (env->spr[SPR_BESCR] & BESCR_GE) && - (env->spr[SPR_BESCR] & BESCR_PME)) { + (env->spr[SPR_BESCR] & BESCR_GE)) { target_ulong nip; - env->spr[SPR_BESCR] &= ~BESCR_GE; /* Clear GE */ - env->spr[SPR_BESCR] |= BESCR_PMEO; /* Set PMEO */ - env->spr[SPR_EBBRR] = env->nip; /* Save NIP for rfebb insn */ - nip = env->spr[SPR_EBBHR]; /* EBB handler */ + /* + * If we have Performance Monitor Event-Based exception + * enabled (BESCR_PME) and a Performance Monitor alert + * occurred (MMCR0_PMAO), clear BESCR_PME and set BESCR_PMEO + * (Performance Monitor Event-Based Exception Occurred). + * + * Software is responsible for clearing both BESCR_PMEO and + * MMCR0_PMAO after the event has been handled. + */ + if ((env->spr[SPR_BESCR] & BESCR_PME) && + (env->spr[SPR_POWER_MMCR0] & MMCR0_PMAO)) { + env->spr[SPR_BESCR] &= ~BESCR_PME; + env->spr[SPR_BESCR] |= BESCR_PMEO; + } + + /* + * In the case of External Event-Based exceptions, do a + * similar logic with BESCR_EE and BESCR_EEO. BESCR_EEO must + * also be cleared by software. + * + * PowerISA 3.1 considers that we'll not have BESCR_PMEO and + * BESCR_EEO set at the same time. We can check for BESCR_PMEO + * being not set in step above to see if this exception was + * trigged by an external event. + */ + if (env->spr[SPR_BESCR] & BESCR_EE && + !(env->spr[SPR_BESCR] & BESCR_PMEO)) { + env->spr[SPR_BESCR] &= ~BESCR_EE; + env->spr[SPR_BESCR] |= BESCR_EEO; + } + + /* + * Clear BESCR_GE, save NIP for 'rfebb' and point the + * execution to the event handler (SPR_EBBHR) address. + */ + env->spr[SPR_BESCR] &= ~BESCR_GE; + env->spr[SPR_EBBRR] = env->nip; + nip = env->spr[SPR_EBBHR]; powerpc_set_excp_state(cpu, nip, env->msr); } /*