From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: Re: [PATCH v6 4/5] arm64: add support for ACPI Low Power Idle(LPI) Date: Mon, 27 Jun 2016 10:50:39 +0100 Message-ID: <5770F6EF.3080902@arm.com> References: <1465915719-8409-1-git-send-email-sudeep.holla@arm.com> <1465915719-8409-5-git-send-email-sudeep.holla@arm.com> <20160622141700.GB2733@red-moon> <576DA047.7080808@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from foss.arm.com ([217.140.101.70]:38983 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751634AbcF0Juo (ORCPT ); Mon, 27 Jun 2016 05:50:44 -0400 In-Reply-To: <576DA047.7080808@linaro.org> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Daniel Lezcano , Lorenzo Pieralisi Cc: Sudeep Holla , "Rafael J . Wysocki" , linux-acpi@vger.kernel.org, Vikas Sajjan , Sunil , Prashanth Prakash , Al Stone , Ashwin Chaugule , linux-kernel@vger.kernel.org, Mark Rutland , linux-arm-kernel@lists.infradead.org Hi, Daniel, On 24/06/16 22:04, Daniel Lezcano wrote: [...] >>> + >>> + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); >>> + if (!psci_states) >>> + return -ENOMEM; >>> + >>> + for (i = 0; i < count; i++) { >>> + u32 state; >>> + >>> + lpi = &pr->power.lpi_states[i + 1]; >>> + state = lpi->address & 0xFFFFFFFF; > > Why is needed to mask 'address' ? > This is as per Section 3.1.1 FFH Usage in LPI state entry methods in [1] [...] >>> int psci_cpu_init_idle(unsigned int cpu) >>> { >>> struct device_node *cpu_node; >>> int ret; >>> >>> + if (!acpi_disabled) >>> + return psci_acpi_cpu_init_idle(cpu); > > Is it possible the case where there is information in both the DT and in > ACPI ? So ACPI is enabled without idle information which is in the DT ? > No, as Rafael mentioned aready. >> >> Either you do this, or we have to add it somehow somewhere in >> drivers/cpuidle to avoid duplicating it. >> >> @Daniel: do you have an opinion on this please ? > > Yes, this function should be added to avoid duplication. > So, I assume you are happy with the way it's handled in this patch ? (I will rename the file as suggested by Lorenzo) -- Regards, Sudeep [1] http://infocenter.arm.com/help/topic/com.arm.doc.den0048a/DEN0048A_ARM_FFH_Specification.pdf