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 CC589C433EF for ; Wed, 5 Jan 2022 10:46:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235222AbiAEKqL (ORCPT ); Wed, 5 Jan 2022 05:46:11 -0500 Received: from foss.arm.com ([217.140.110.172]:43194 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235139AbiAEKqL (ORCPT ); Wed, 5 Jan 2022 05:46:11 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 738971042; Wed, 5 Jan 2022 02:46:10 -0800 (PST) Received: from lpieralisi (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AB2583F774; Wed, 5 Jan 2022 02:46:08 -0800 (PST) Date: Wed, 5 Jan 2022 10:46:02 +0000 From: Lorenzo Pieralisi To: Ilkka Koskinen Cc: guohanjun@huawei.com, sudeep.holla@arm.com, rafael@kernel.org, linux@armlinux.org.uk, lenb@kernel.org, robert.moore@intel.com, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, patches@amperecomputing.com, scott@os.amperecomputing.com, darren@os.amperecomputing.com, james.morse@arm.com Subject: Re: [PATCH v3 2/2] ACPI: AGDI: Add driver for Arm Generic Diagnostic Dump and Reset device Message-ID: <20220105104602.GA4752@lpieralisi> References: <20211231033725.21109-1-ilkka@os.amperecomputing.com> <20211231033725.21109-3-ilkka@os.amperecomputing.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211231033725.21109-3-ilkka@os.amperecomputing.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org [+James, for SDEI bits] On Thu, Dec 30, 2021 at 07:37:25PM -0800, Ilkka Koskinen wrote: > ACPI for Arm Components 1.1 Platform Design Document v1.1 [0] specifices > Arm Generic Diagnostic Device Interface (AGDI). It allows an admin to > issue diagnostic dump and reset via an SDEI event or an interrupt. > This patch implements SDEI path. > > [0] https://developer.arm.com/documentation/den0093/latest/ > > Signed-off-by: Ilkka Koskinen > --- > drivers/acpi/arm64/Kconfig | 8 +++ > drivers/acpi/arm64/Makefile | 1 + > drivers/acpi/arm64/agdi.c | 125 ++++++++++++++++++++++++++++++++++++ > 3 files changed, 134 insertions(+) > create mode 100644 drivers/acpi/arm64/agdi.c > > diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig > index 6dba187f4f2e..24869ba5b365 100644 > --- a/drivers/acpi/arm64/Kconfig > +++ b/drivers/acpi/arm64/Kconfig > @@ -8,3 +8,11 @@ config ACPI_IORT > > config ACPI_GTDT > bool > + > +config ACPI_AGDI > + bool "Arm Generic Diagnostic Dump and Reset Device Interface" > + depends on ARM_SDE_INTERFACE > + help > + Arm Generic Diagnostic Dump and Reset Device Interface (AGDI) is > + a standard that enables issuing a non-maskable diagnostic dump and > + reset command. > diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile > index 66acbe77f46e..7b9e4045659d 100644 > --- a/drivers/acpi/arm64/Makefile > +++ b/drivers/acpi/arm64/Makefile > @@ -1,4 +1,5 @@ > # SPDX-License-Identifier: GPL-2.0-only > +obj-$(CONFIG_ACPI_AGDI) += agdi.o > obj-$(CONFIG_ACPI_IORT) += iort.o > obj-$(CONFIG_ACPI_GTDT) += gtdt.o > obj-y += dma.o > diff --git a/drivers/acpi/arm64/agdi.c b/drivers/acpi/arm64/agdi.c > new file mode 100644 > index 000000000000..6525ccbae5c1 > --- /dev/null > +++ b/drivers/acpi/arm64/agdi.c > @@ -0,0 +1,125 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * This file implements handling of > + * Arm Generic Diagnostic Dump and Reset Interface table (AGDI) > + * > + * Copyright (c) 2021, Ampere Computing LLC > + */ > + > +#define pr_fmt(fmt) "ACPI: AGDI: " fmt > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include Nit: alphabetical order. > + > +struct agdi_data { > + int sdei_event; > +}; > + > +static int agdi_sdei_handler(u32 sdei_event, struct pt_regs *regs, void *arg) > +{ > + nmi_panic(regs, "Arm Generic Diagnostic Dump and Reset SDEI event issued"); > + return 0; > +} > + > +static int agdi_sdei_probe(struct platform_device *pdev, > + struct agdi_data *adata) > +{ > + int err; > + > + err = sdei_event_register(adata->sdei_event, agdi_sdei_handler, pdev); > + if (err) { > + dev_err(&pdev->dev, "Failed to register for SDEI event %d", > + adata->sdei_event); > + return err; > + } > + > + err = sdei_event_enable(adata->sdei_event); > + if (err) { > + sdei_event_unregister(adata->sdei_event); > + dev_err(&pdev->dev, "Failed to enable event %d\n", > + adata->sdei_event); > + return err; > + } > + > + return 0; > +} > + > +static int agdi_probe(struct platform_device *pdev) > +{ > + struct agdi_data *adata; > + > + adata = dev_get_platdata(&pdev->dev); > + if (!adata) > + return -EINVAL; > + > + return agdi_sdei_probe(pdev, adata); > +} > + > +static int agdi_remove(struct platform_device *pdev) > +{ > + struct agdi_data *adata = platform_get_drvdata(pdev); > + > + sdei_event_disable(adata->sdei_event); > + sdei_event_unregister(adata->sdei_event); > + > + return 0; > +} > + > +static struct platform_driver agdi_driver = { > + .driver = { > + .name = "agdi", > + }, > + .probe = agdi_probe, > + .remove = agdi_remove, > +}; May I ask why we need a platform device (and driver) to register an SDEI event ? > +static int __init agdi_init(void) > +{ > + int ret; > + acpi_status status; > + struct acpi_table_agdi *agdi_table; > + struct agdi_data pdata; > + struct platform_device *pdev; > + > + if (acpi_disabled) > + return 0; Why don't we call agdi_init() from acpi_init() as we do for IORT/VIOT ? I don't think it is necessary to add a device_initcall(), with related ordering dependencies. > + > + status = acpi_get_table(ACPI_SIG_AGDI, 0, > + (struct acpi_table_header **) &agdi_table); > + if (ACPI_FAILURE(status)) > + return -ENODEV; > + > + if (agdi_table->flags & ACPI_AGDI_SIGNALING_MODE) { Is this because specs need updating ? > + pr_warn("Interrupt signaling is not supported"); > + ret = -ENODEV; > + goto err_put_table; > + } > + > + pdata.sdei_event = agdi_table->sdei_event; > + > + pdev = platform_device_register_data(NULL, "agdi", 0, &pdata, sizeof(pdata)); > + if (IS_ERR(pdev)) { > + ret = PTR_ERR(pdev); > + goto err_put_table; > + } > + > + ret = platform_driver_register(&agdi_driver); > + if (ret) > + goto err_device_unregister; > + > + acpi_put_table((struct acpi_table_header *)agdi_table); > + return 0; > + > +err_device_unregister: > + platform_device_unregister(pdev); > +err_put_table: > + acpi_put_table((struct acpi_table_header *)agdi_table); > + return ret; > +} > +device_initcall(agdi_init); See above. Thanks, Lorenzo