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819a88263d
ARM64 CPU operations such as cpu_init and cpu_init_idle take a struct device_node pointer as a parameter, which corresponds to the device tree node of the logical cpu on which the operation has to be applied. With the advent of ACPI on arm64, where MADT static table entries are used to initialize cpus, the device tree node parameter in cpu_ops hooks become useless when booting with ACPI, since in that case cpu device tree nodes are not present and can not be used for cpu initialization. The current cpu_init hook requires a struct device_node pointer parameter because it is called while parsing the device tree to initialize CPUs, when the cpu_logical_map (that is used to match a cpu node reg property to a device tree node) for a given logical cpu id is not set up yet. This means that the cpu_init hook cannot rely on the of_get_cpu_node function to retrieve the device tree node corresponding to the logical cpu id passed in as parameter, so the cpu device tree node must be passed in as a parameter to fix this catch-22 dependency cycle. This patch reshuffles the cpu_logical_map initialization code so that the cpu_init cpu_ops hook can safely use the of_get_cpu_node function to retrieve the cpu device tree node, removing the need for the device tree node pointer parameter. In the process, the patch removes device tree node parameters from all cpu_ops hooks, in preparation for SMP DT/ACPI cpus initialization consolidation. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Mark Rutland <mark.rutland@arm.com> [DT] Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
/*
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* ARM64 CPU idle arch support
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*
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* Copyright (C) 2014 ARM Ltd.
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* Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <asm/cpuidle.h>
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#include <asm/cpu_ops.h>
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int arm_cpuidle_init(unsigned int cpu)
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{
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int ret = -EOPNOTSUPP;
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if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_init_idle)
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ret = cpu_ops[cpu]->cpu_init_idle(cpu);
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return ret;
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}
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/**
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* cpu_suspend() - function to enter a low-power idle state
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* @arg: argument to pass to CPU suspend operations
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*
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* Return: 0 on success, -EOPNOTSUPP if CPU suspend hook not initialized, CPU
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* operations back-end error code otherwise.
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*/
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int cpu_suspend(unsigned long arg)
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{
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int cpu = smp_processor_id();
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/*
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* If cpu_ops have not been registered or suspend
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* has not been initialized, cpu_suspend call fails early.
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*/
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if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_suspend)
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return -EOPNOTSUPP;
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return cpu_ops[cpu]->cpu_suspend(arg);
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}
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