From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Mon, 27 Jun 2016 10:50:39 +0100 Subject: [PATCH v6 4/5] arm64: add support for ACPI Low Power Idle(LPI) In-Reply-To: <576DA047.7080808@linaro.org> 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> Message-ID: <5770F6EF.3080902@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: 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