Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754711AbcKUOi4 (ORCPT ); Mon, 21 Nov 2016 09:38:56 -0500 Received: from mail-it0-f49.google.com ([209.85.214.49]:35983 "EHLO mail-it0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753830AbcKUOix (ORCPT ); Mon, 21 Nov 2016 09:38:53 -0500 MIME-Version: 1.0 In-Reply-To: <20161118195657.GM1197@leverpostej> References: <1479304148-2965-1-git-send-email-fu.wei@linaro.org> <1479304148-2965-9-git-send-email-fu.wei@linaro.org> <20161118195657.GM1197@leverpostej> From: Fu Wei Date: Mon, 21 Nov 2016 22:38:51 +0800 Message-ID: Subject: Re: [PATCH v16 08/15] clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing, and call it only if acpi disabled. To: Mark Rutland Cc: "Rafael J. Wysocki" , Len Brown , Daniel Lezcano , Thomas Gleixner , Marc Zyngier , Lorenzo Pieralisi , 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 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4152 Lines: 122 Hi Mark, On 19 November 2016 at 03:56, Mark Rutland wrote: > On Wed, Nov 16, 2016 at 09:49:01PM +0800, fu.wei@linaro.org wrote: >> From: Fu Wei >> >> The patch refactor original arch_timer_needs_probing function: >> (1) Separate out arch_timer_needs_probing from arch_timer_common_init, >> and call it only if acpi disabled. >> (2) Rename arch_timer_needs_probing to arch_timer_needs_of_probing. > > Please write a real commit message. OK, how about this: clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing, only use it in the DT init code Currently, the arch_timer_common_init uses arch_timer_needs_probing call to wait for both timers been probed which is only for booting from DT. For booting from ACPI, we don't need these in arch_timer_common_init, these code should be only in the DT init code. This patch seperates arch_timer_needs_probing related code out into a new function named arch_timer_needs_of_probing, and then reworks arch_timer_of_init to use it, so that we can keep this only in the DT init code. > >> Signed-off-by: Fu Wei >> --- >> drivers/clocksource/arm_arch_timer.c | 34 +++++++++++++++++++--------------- >> 1 file changed, 19 insertions(+), 15 deletions(-) >> >> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c >> index fe4e812..9ddc091 100644 >> --- a/drivers/clocksource/arm_arch_timer.c >> +++ b/drivers/clocksource/arm_arch_timer.c >> @@ -792,15 +792,28 @@ static const struct of_device_id arch_timer_mem_of_match[] __initconst = { >> {}, >> }; >> >> -static bool __init >> -arch_timer_needs_probing(int type, const struct of_device_id *matches) >> +static bool __init arch_timer_needs_of_probing(void) >> { >> struct device_node *dn; >> bool needs_probing = false; >> + unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM; >> + >> + /* We have two timers, and both device-tree nodes are probed. */ >> + if ((arch_timers_present & mask) == mask) >> + return false; >> + >> + /* >> + * Only one type of timer is probed, >> + * check if we have another type of timer node in device-tree. >> + */ >> + if (arch_timers_present & ARCH_TIMER_TYPE_CP15) >> + dn = of_find_matching_node(NULL, arch_timer_mem_of_match); >> + else >> + dn = of_find_matching_node(NULL, arch_timer_of_match); >> >> - dn = of_find_matching_node(NULL, matches); >> - if (dn && of_device_is_available(dn) && !(arch_timers_present & type)) >> + if (dn && of_device_is_available(dn)) >> needs_probing = true; >> + >> of_node_put(dn); >> >> return needs_probing; >> @@ -808,17 +821,8 @@ arch_timer_needs_probing(int type, const struct of_device_id *matches) >> >> static int __init arch_timer_common_init(void) >> { >> - unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM; >> - >> - /* Wait until both nodes are probed if we have two timers */ >> - if ((arch_timers_present & mask) != mask) { >> - if (arch_timer_needs_probing(ARCH_TIMER_TYPE_MEM, >> - arch_timer_mem_of_match)) >> - return 0; >> - if (arch_timer_needs_probing(ARCH_TIMER_TYPE_CP15, >> - arch_timer_of_match)) >> - return 0; >> - } > > Why can't we just move this into the DT-specific caller of > arch_timer_common_init()? yes, I have thought about this, but that means we have to split arch_timer_init, and use arch_timer_register and arch_timer_common_init directly in arch_timer_of_init. In another word, I also need to modify arch_timer_of_init, not only arch_timer_common_init, but let me have a try in v17, see if you like it. > > Thanks > Mark. > >> + if (acpi_disabled && arch_timer_needs_of_probing()) >> + return 0; >> >> arch_timer_banner(arch_timers_present); >> arch_counter_register(arch_timers_present); >> -- >> 2.7.4 >> -- Best regards, Fu Wei Software Engineer Red Hat