From patchwork Sun Oct 16 03:40:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "lihuisong (C)" X-Patchwork-Id: 13007705 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 661E2C4332F for ; Sun, 16 Oct 2022 03:40:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229554AbiJPDkc (ORCPT ); Sat, 15 Oct 2022 23:40:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229463AbiJPDkb (ORCPT ); Sat, 15 Oct 2022 23:40:31 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9ADDB2F657; Sat, 15 Oct 2022 20:40:28 -0700 (PDT) Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Mqm496DGhzVjW5; Sun, 16 Oct 2022 11:35:53 +0800 (CST) Received: from kwepemm600004.china.huawei.com (7.193.23.242) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Sun, 16 Oct 2022 11:39:57 +0800 Received: from localhost.localdomain (10.69.192.56) 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; Sun, 16 Oct 2022 11:39:56 +0800 From: Huisong Li To: , CC: , , , , , , Subject: [RFC] ACPI: PCC: Support shared interrupt for multiple subspaces Date: Sun, 16 Oct 2022 11:40:43 +0800 Message-ID: <20221016034043.52227-1-lihuisong@huawei.com> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) 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 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;