From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lorenzo Pieralisi Subject: Re: [PATCH v22 07/11] acpi/arm64: Add GTDT table parse driver Date: Wed, 29 Mar 2017 11:21:18 +0100 Message-ID: <20170329102118.GB10807@red-moon> References: <20170321163122.9183-1-fu.wei@linaro.org> <20170321163122.9183-8-fu.wei@linaro.org> <20170328113535.GA17440@red-moon> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from foss.arm.com ([217.140.101.70]:59632 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755116AbdC2KUz (ORCPT ); Wed, 29 Mar 2017 06:20:55 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Fu Wei Cc: "Rafael J. Wysocki" , Len Brown , Daniel Lezcano , Thomas Gleixner , Marc Zyngier , Mark Rutland , Sudeep Holla , Hanjun Guo , linux-arm-kernel@lists.infradead.org, Linaro ACPI Mailman List , Linux Kernel Mailing List , ACPI Devel Maling List , rruigrok@codeaurora.org, "Abdulhamid, Harb" , Christopher Covington , Timur Tabi , G Gregory , Al Stone , Jon Masters , Wei On Wed, Mar 29, 2017 at 05:48:17PM +0800, Fu Wei wrote: [...] > * @platform_timer_count: It points to a integer variable which is used > * for storing the number of platform timers. > * This pointer could be NULL, if the caller > * doesn't need this info. > > > > >> + * > >> + * Return: 0 if success, -EINVAL if error. > >> + */ > >> +int __init acpi_gtdt_init(struct acpi_table_header *table, > >> + int *platform_timer_count) > >> +{ > >> + int ret = 0; > >> + int timer_count = 0; > >> + void *platform_timer = NULL; > >> + struct acpi_table_gtdt *gtdt; > >> + > >> + gtdt = container_of(table, struct acpi_table_gtdt, header); > >> + acpi_gtdt_desc.gtdt = gtdt; > >> + acpi_gtdt_desc.gtdt_end = (void *)table + table->length; > >> + > >> + if (table->revision < 2) > >> + pr_warn("Revision:%d doesn't support Platform Timers.\n", > >> + table->revision); > > > > Ok, two points here. First, I am not sure why you should warn if the > > table revision is < 2, is that a FW bug ? I do not think it is, you > > can just return 0. > > I used pr_debug here before v20, then I got Hanjun's suggestion: > ------- > GTDT table revision is updated to 2 in ACPI 5.1, we will > not support ACPI version under 5.1 and disable ACPI in FADT > parse before this code is called, so if we get revision > <2 here, I think we need to print warning (we need to keep > the firmware stick to the spec on ARM64). > ------- > https://lkml.org/lkml/2017/1/19/82 > > So I started to use pr_warn. Thanks for the explanation, so it is a FW bug and the warning is granted :) just leave it there. Still, please check my comment on acpi_gtdt_init() being called multiple times on patch 11. Thanks, Lorenzo From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755563AbdC2KU5 (ORCPT ); Wed, 29 Mar 2017 06:20:57 -0400 Received: from foss.arm.com ([217.140.101.70]:59632 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755116AbdC2KUz (ORCPT ); Wed, 29 Mar 2017 06:20:55 -0400 Date: Wed, 29 Mar 2017 11:21:18 +0100 From: Lorenzo Pieralisi To: Fu Wei Cc: "Rafael J. Wysocki" , Len Brown , Daniel Lezcano , Thomas Gleixner , Marc Zyngier , Mark Rutland , Sudeep Holla , Hanjun Guo , linux-arm-kernel@lists.infradead.org, Linaro ACPI Mailman List , Linux Kernel Mailing List , ACPI Devel Maling List , rruigrok@codeaurora.org, "Abdulhamid, Harb" , Christopher Covington , Timur Tabi , G Gregory , Al Stone , Jon Masters , Wei Huang , Arnd Bergmann , Catalin Marinas , Will Deacon , Suravee Suthikulpanit , Leo Duran , Wim Van Sebroeck , Guenter Roeck , linux-watchdog@vger.kernel.org, Tomasz Nowicki , Christoffer Dall , Julien Grall Subject: Re: [PATCH v22 07/11] acpi/arm64: Add GTDT table parse driver Message-ID: <20170329102118.GB10807@red-moon> References: <20170321163122.9183-1-fu.wei@linaro.org> <20170321163122.9183-8-fu.wei@linaro.org> <20170328113535.GA17440@red-moon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 29, 2017 at 05:48:17PM +0800, Fu Wei wrote: [...] > * @platform_timer_count: It points to a integer variable which is used > * for storing the number of platform timers. > * This pointer could be NULL, if the caller > * doesn't need this info. > > > > >> + * > >> + * Return: 0 if success, -EINVAL if error. > >> + */ > >> +int __init acpi_gtdt_init(struct acpi_table_header *table, > >> + int *platform_timer_count) > >> +{ > >> + int ret = 0; > >> + int timer_count = 0; > >> + void *platform_timer = NULL; > >> + struct acpi_table_gtdt *gtdt; > >> + > >> + gtdt = container_of(table, struct acpi_table_gtdt, header); > >> + acpi_gtdt_desc.gtdt = gtdt; > >> + acpi_gtdt_desc.gtdt_end = (void *)table + table->length; > >> + > >> + if (table->revision < 2) > >> + pr_warn("Revision:%d doesn't support Platform Timers.\n", > >> + table->revision); > > > > Ok, two points here. First, I am not sure why you should warn if the > > table revision is < 2, is that a FW bug ? I do not think it is, you > > can just return 0. > > I used pr_debug here before v20, then I got Hanjun's suggestion: > ------- > GTDT table revision is updated to 2 in ACPI 5.1, we will > not support ACPI version under 5.1 and disable ACPI in FADT > parse before this code is called, so if we get revision > <2 here, I think we need to print warning (we need to keep > the firmware stick to the spec on ARM64). > ------- > https://lkml.org/lkml/2017/1/19/82 > > So I started to use pr_warn. Thanks for the explanation, so it is a FW bug and the warning is granted :) just leave it there. Still, please check my comment on acpi_gtdt_init() being called multiple times on patch 11. Thanks, Lorenzo From mboxrd@z Thu Jan 1 00:00:00 1970 From: lorenzo.pieralisi@arm.com (Lorenzo Pieralisi) Date: Wed, 29 Mar 2017 11:21:18 +0100 Subject: [PATCH v22 07/11] acpi/arm64: Add GTDT table parse driver In-Reply-To: References: <20170321163122.9183-1-fu.wei@linaro.org> <20170321163122.9183-8-fu.wei@linaro.org> <20170328113535.GA17440@red-moon> Message-ID: <20170329102118.GB10807@red-moon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Mar 29, 2017 at 05:48:17PM +0800, Fu Wei wrote: [...] > * @platform_timer_count: It points to a integer variable which is used > * for storing the number of platform timers. > * This pointer could be NULL, if the caller > * doesn't need this info. > > > > >> + * > >> + * Return: 0 if success, -EINVAL if error. > >> + */ > >> +int __init acpi_gtdt_init(struct acpi_table_header *table, > >> + int *platform_timer_count) > >> +{ > >> + int ret = 0; > >> + int timer_count = 0; > >> + void *platform_timer = NULL; > >> + struct acpi_table_gtdt *gtdt; > >> + > >> + gtdt = container_of(table, struct acpi_table_gtdt, header); > >> + acpi_gtdt_desc.gtdt = gtdt; > >> + acpi_gtdt_desc.gtdt_end = (void *)table + table->length; > >> + > >> + if (table->revision < 2) > >> + pr_warn("Revision:%d doesn't support Platform Timers.\n", > >> + table->revision); > > > > Ok, two points here. First, I am not sure why you should warn if the > > table revision is < 2, is that a FW bug ? I do not think it is, you > > can just return 0. > > I used pr_debug here before v20, then I got Hanjun's suggestion: > ------- > GTDT table revision is updated to 2 in ACPI 5.1, we will > not support ACPI version under 5.1 and disable ACPI in FADT > parse before this code is called, so if we get revision > <2 here, I think we need to print warning (we need to keep > the firmware stick to the spec on ARM64). > ------- > https://lkml.org/lkml/2017/1/19/82 > > So I started to use pr_warn. Thanks for the explanation, so it is a FW bug and the warning is granted :) just leave it there. Still, please check my comment on acpi_gtdt_init() being called multiple times on patch 11. Thanks, Lorenzo