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 9F786C25B48 for ; Fri, 27 Oct 2023 17:45:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231594AbjJ0Rpq (ORCPT ); Fri, 27 Oct 2023 13:45:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231464AbjJ0Rpq (ORCPT ); Fri, 27 Oct 2023 13:45:46 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 988ABF3; Fri, 27 Oct 2023 10:45:40 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1698428739; 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: in-reply-to:in-reply-to:references:references; bh=vCF2sTMjoJARe87DP7lAD8rcZvlM4BFzZKH7cV3QuU8=; b=xXX2ovs1OHhXbwDuZac6CP8IsOrVj54bZeD5nyxWlPUBOXUniX1BJWPV+PcVr7obtLN3eF I6uPBnLwqsSeXJfTpISEjW/ksbeWDMkDlGhuSLkQd0gwCvAm+Ogc1qakMhd99FaKFmFOz6 1GIjy1E+N/YDe03TxrnRIU53J4jidS28NuERCZkDyMkX8X5wFJu/OtV20oF773goJYLcMm /ktLuCbvSshkq1Zxca8OxoWF8VJ4zqw5Ohr8CYTRGpLm9x96JuE60jmezp5gm6X3Yn94AK 7ns6idG1lqprpc0Y27+8vH0y0yrCC8o1DwW3zTycAy/bFh5YoXh4wv0+CbwiwA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1698428739; 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: in-reply-to:in-reply-to:references:references; bh=vCF2sTMjoJARe87DP7lAD8rcZvlM4BFzZKH7cV3QuU8=; b=WWHizKPPbjghvXPvf1/QyrM9sNTsNYrmVq6GoM+JMN89I9M6CgHAYJRHoOSGLIiqmVpfsl B+qpDGnW7YiT4hDg== To: Bjorn Helgaas , Sunil V L Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-serial@vger.kernel.org, Catalin Marinas , Will Deacon , Paul Walmsley , Palmer Dabbelt , Albert Ou , "Rafael J . Wysocki" , Len Brown , Bjorn Helgaas , Anup Patel , Greg Kroah-Hartman , Jiri Slaby , Conor Dooley , Andrew Jones , Atish Kumar Patra , Haibo Xu , Marc Zyngier Subject: Re: [RFC PATCH v2 13/21] irqchip: riscv-intc: Add ACPI support for AIA In-Reply-To: <20231026165150.GA1825130@bhelgaas> References: <20231026165150.GA1825130@bhelgaas> Date: Fri, 27 Oct 2023 19:45:38 +0200 Message-ID: <87jzr82c3h.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Thu, Oct 26 2023 at 11:51, Bjorn Helgaas wrote: > On Thu, Oct 26, 2023 at 01:53:36AM +0530, Sunil V L wrote: >> The RINTC subtype structure in MADT also has information about other >> interrupt controllers like MMIO. So, save those information and provide >> interfaces to retrieve them when required by corresponding drivers. > >> @@ -218,7 +306,19 @@ static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header, > >> + * MSI controller (IMSIC) in RISC-V is optional. So, unless >> + * IMSIC is discovered, set system wide MSI support as >> + * unsupported. Once IMSIC is probed, MSI support will be set. >> + */ >> + pci_no_msi(); > > It doesn't seem like we should have to tell the PCI core about > functionality we *don't* have. > > I would think IMSIC would be detected before enumerating PCI devices > that might use it, and if we *haven't* found an IMSIC by the time we > get to pci_register_host_bridge(), would/should we set > PCI_BUS_FLAGS_NO_MSI there? > > I see Thomas is cc'd; he'd have better insight. I was not really involved with this bus and MSI domain logic. Marc should know. CC'ed. Thanks, tglx