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 2E623C433FE for ; Wed, 26 Oct 2022 06:10:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232743AbiJZGKW (ORCPT ); Wed, 26 Oct 2022 02:10:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229995AbiJZGKV (ORCPT ); Wed, 26 Oct 2022 02:10:21 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD83E2DAA6; Tue, 25 Oct 2022 23:10:17 -0700 (PDT) Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Mxz1Q0J98zHtv1; Wed, 26 Oct 2022 14:10:02 +0800 (CST) Received: from kwepemm600004.china.huawei.com (7.193.23.242) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 26 Oct 2022 14:10:14 +0800 Received: from [10.67.103.231] (10.67.103.231) by kwepemm600004.china.huawei.com (7.193.23.242) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 26 Oct 2022 14:10:14 +0800 Message-ID: <6d00d240-0c86-d593-6efe-44fec21421a8@huawei.com> Date: Wed, 26 Oct 2022 14:10:13 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: [RFC] ACPI: PCC: Support shared interrupt for multiple subspaces To: , CC: , , , , , , Loc Ho , Hoan Tran References: <20221016034043.52227-1-lihuisong@huawei.com> From: "lihuisong (C)" In-Reply-To: <20221016034043.52227-1-lihuisong@huawei.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.103.231] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemm600004.china.huawei.com (7.193.23.242) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Kindly ping. 在 2022/10/16 11:40, Huisong Li 写道: > As ACPI protocol descripted, if interrupts are level, a GSIV may > be shared by multiple subspaces, but each one must have unique > platform interrupt ack preserve and ack set masks. Therefore, need > set to shared interrupt for types that can distinguish interrupt > response channel if platform interrupt mode is level triggered. > > The distinguishing point isn't definitely command complete register. > Because the two status values of command complete indicate that > there is no interrupt in a subspace('1' means subspace is free for > use, and '0' means platform is processing the command). On the whole, > the platform interrupt ack register is more suitable for this role. > As ACPI protocol said, If the subspace does support interrupts, and > these are level, this register must be supplied. And is used to clear > the interrupt by using a read, modify, write sequence. This register > is a 'WR' register, the bit corresponding to the subspace is '1' when > the command is completed, or is '0'. > > Therefore, register shared interrupt for multiple subspaces if support > platform interrupt ack register and interrupts are level, and read the > ack register to ensure the idle or unfinished command channels to > quickly return IRQ_NONE. > > Signed-off-by: Huisong Li > --- > drivers/mailbox/pcc.c | 27 +++++++++++++++++++++++++-- > 1 file changed, 25 insertions(+), 2 deletions(-) > > diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c > index 3c2bc0ca454c..86c6cc44c73d 100644 > --- a/drivers/mailbox/pcc.c > +++ b/drivers/mailbox/pcc.c > @@ -100,6 +100,7 @@ struct pcc_chan_info { > struct pcc_chan_reg cmd_update; > struct pcc_chan_reg error; > int plat_irq; > + u8 plat_irq_trigger; > }; > > #define to_pcc_chan_info(c) container_of(c, struct pcc_chan_info, chan) > @@ -236,6 +237,15 @@ static irqreturn_t pcc_mbox_irq(int irq, void *p) > int ret; > > pchan = chan->con_priv; > + ret = pcc_chan_reg_read(&pchan->plat_irq_ack, &val); > + if (ret) > + return IRQ_NONE; > + /* Irq ack GAS exist and check if this interrupt has the channel. */ > + if (pchan->plat_irq_ack.gas) { > + val &= pchan->plat_irq_ack.set_mask; > + if (val == 0) > + return IRQ_NONE; > + } > > ret = pcc_chan_reg_read(&pchan->cmd_complete, &val); > if (ret) > @@ -309,10 +319,21 @@ pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id) > spin_unlock_irqrestore(&chan->lock, flags); > > if (pchan->plat_irq > 0) { > + unsigned long irqflags; > int rc; > > - rc = devm_request_irq(dev, pchan->plat_irq, pcc_mbox_irq, 0, > - MBOX_IRQ_NAME, chan); > + /* > + * As ACPI protocol descripted, if interrupts are level, a GSIV > + * may be shared by multiple subspaces. > + * Therefore, register shared interrupt for multiple subspaces > + * if support platform interrupt ack register and interrupts > + * are level. > + */ > + irqflags = (pchan->plat_irq_ack.gas && > + pchan->plat_irq_trigger == ACPI_LEVEL_SENSITIVE) ? > + IRQF_SHARED : 0; > + rc = devm_request_irq(dev, pchan->plat_irq, pcc_mbox_irq, > + irqflags, MBOX_IRQ_NAME, chan); > if (unlikely(rc)) { > dev_err(dev, "failed to register PCC interrupt %d\n", > pchan->plat_irq); > @@ -457,6 +478,8 @@ static int pcc_parse_subspace_irq(struct pcc_chan_info *pchan, > pcct_ss->platform_interrupt); > return -EINVAL; > } > + pchan->plat_irq_trigger = (pcct_ss->flags & ACPI_PCCT_INTERRUPT_MODE) ? > + ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE; > > if (pcct_ss->header.type == ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) { > struct acpi_pcct_hw_reduced_type2 *pcct2_ss = (void *)pcct_ss;