Revert "drivers: cpuidle: implement OF based idle states infrastructure"

This reverts commit 830b8519a41c5b13b1787ef94f31ad1d3507ec73.

4 files changed, 0 insertions, 292 deletions

diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index e4d3913fe330..c4cc27e5c8a5 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -31,15 +31,6 @@ config CPU_IDLE_GOV_MENU
 config ARCH_NEEDS_CPU_IDLE_COUPLED
 	def_bool n
 
-config OF_IDLE_STATES
-        bool "Idle states DT support"
-	depends on ARM || ARM64
-	default n
-	help
-	 Allows the CPU idle framework to initialize CPU idle drivers
-	 state data by using DT provided nodes compliant with idle states
-	 device tree bindings.
-
 if CPU_IDLE
 
 config CPU_IDLE_CALXEDA
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index d41366a7838c..0d8bd55e776f 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -4,7 +4,6 @@
 
 obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
 obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
-obj-$(CONFIG_OF_IDLE_STATES)		  += of_idle_states.o
 
 obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o
 obj-$(CONFIG_ARCH_KIRKWOOD) += cpuidle-kirkwood.o
diff --git a/drivers/cpuidle/of_idle_states.c b/drivers/cpuidle/of_idle_states.c
deleted file mode 100644
index eceb1b4c4657..000000000000
--- a/drivers/cpuidle/of_idle_states.c
+++ /dev/null
@@ -1,274 +0,0 @@
-/*
- * OF idle states parsing code.
- *
- * Copyright (C) 2014 ARM Ltd.
- * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/cpuidle.h>
-#include <linux/cpumask.h>
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/list.h>
-#include <linux/list_sort.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/slab.h>
-
-#include "of_idle_states.h"
-
-struct state_elem {
-	struct list_head list;
-	struct device_node *node;
-	int val;
-};
-
-static struct list_head head __initdata = LIST_HEAD_INIT(head);
-
-static bool __init state_cpu_valid(struct device_node *state_node,
-				   struct device_node *cpu_node)
-{
-	int i = 0;
-	struct device_node *cpu_state;
-
-	while ((cpu_state = of_parse_phandle(cpu_node,
-					     "cpu-idle-states", i++))) {
-		if (cpu_state && state_node == cpu_state) {
-			of_node_put(cpu_state);
-			return true;
-		}
-		of_node_put(cpu_state);
-	}
-	return false;
-}
-
-static bool __init state_cpus_valid(const cpumask_t *cpus,
-				    struct device_node *state_node)
-{
-	int cpu;
-	struct device_node *cpu_node;
-
-	/*
-	 * Check if state is valid on driver cpumask cpus
-	 */
-	for_each_cpu(cpu, cpus) {
-		cpu_node = of_get_cpu_node(cpu, NULL);
-
-		if (!cpu_node) {
-			pr_err("Missing device node for CPU %d\n", cpu);
-			return false;
-		}
-
-		if (!state_cpu_valid(state_node, cpu_node))
-			return false;
-	}
-
-	return true;
-}
-
-static int __init state_cmp(void *priv, struct list_head *a,
-			    struct list_head *b)
-{
-	struct state_elem *ela, *elb;
-
-	ela = container_of(a, struct state_elem, list);
-	elb = container_of(b, struct state_elem, list);
-
-	return ela->val - elb->val;
-}
-
-static int __init add_state_node(cpumask_t *cpumask,
-				 struct device_node *state_node)
-{
-	struct state_elem *el;
-	u32 val;
-
-	pr_debug(" * %s...\n", state_node->full_name);
-
-	if (!state_cpus_valid(cpumask, state_node))
-		return -EINVAL;
-	/*
-	 * Parse just the value required to sort the states.
-	 */
-	if (of_property_read_u32(state_node, "min-residency-us",
-				 &val)) {
-		pr_debug(" * %s missing min-residency-us property\n",
-			 state_node->full_name);
-		return -EINVAL;
-	}
-
-	el = kmalloc(sizeof(*el), GFP_KERNEL);
-	if (!el) {
-		pr_err("%s failed to allocate memory\n", __func__);
-		return -ENOMEM;
-	}
-
-	el->node = state_node;
-	el->val = val;
-	list_add_tail(&el->list, &head);
-
-	return 0;
-}
-
-static void __init init_state_node(struct cpuidle_driver *drv,
-				   struct device_node *state_node,
-				   int *cnt)
-{
-	struct cpuidle_state *idle_state;
-
-	pr_debug(" * %s...\n", state_node->full_name);
-
-	idle_state = &drv->states[*cnt];
-
-	if (of_property_read_u32(state_node, "exit-latency-us",
-				 &idle_state->exit_latency)) {
-		pr_debug(" * %s missing exit-latency-us property\n",
-			     state_node->full_name);
-		return;
-	}
-
-	if (of_property_read_u32(state_node, "min-residency-us",
-				 &idle_state->target_residency)) {
-		pr_debug(" * %s missing min-residency-us property\n",
-			     state_node->full_name);
-		return;
-	}
-	/*
-	 * It is unknown to the idle driver if and when the tick_device
-	 * loses context when the CPU enters the idle states. To solve
-	 * this issue the tick device must be linked to a power domain
-	 * so that the idle driver can check on which states the device
-	 * loses its context. Current code takes the conservative choice
-	 * of defining the idle state as one where the tick device always
-	 * loses its context. On platforms where tick device never loses
-	 * its context (ie it is not a C3STOP device) this turns into
-	 * a nop. On platforms where the tick device does lose context in some
-	 * states, this code can be optimized, when power domain specifications
-	 * for ARM CPUs are finalized.
-	 */
-	idle_state->flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TIMER_STOP;
-
-	strncpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN);
-	strncpy(idle_state->desc, state_node->name, CPUIDLE_NAME_LEN);
-
-	(*cnt)++;
-}
-
-static int __init init_idle_states(struct cpuidle_driver *drv,
-				   struct device_node *state_nodes[],
-				   unsigned int start_idx, bool init_nodes)
-{
-	struct state_elem *el;
-	struct list_head *curr, *tmp;
-	unsigned int cnt = start_idx;
-
-	list_for_each_entry(el, &head, list) {
-		/*
-		 * Check if the init function has to fill the
-		 * state_nodes array on behalf of the CPUidle driver.
-		 */
-		if (init_nodes)
-			state_nodes[cnt] = el->node;
-		/*
-		 * cnt is updated on return if a state was added.
-		 */
-		init_state_node(drv, el->node, &cnt);
-
-		if (cnt == CPUIDLE_STATE_MAX) {
-			pr_warn("State index reached static CPU idle state limit\n");
-			break;
-		}
-	}
-
-	drv->state_count = cnt;
-
-	list_for_each_safe(curr, tmp, &head) {
-		list_del(curr);
-		kfree(container_of(curr, struct state_elem, list));
-	}
-
-	/*
-	 * If no idle states are detected, return an error and let the idle
-	 * driver initialization fail accordingly.
-	 */
-	return (cnt > start_idx) ? 0 : -ENODATA;
-}
-
-static void __init add_idle_states(struct cpuidle_driver *drv,
-				   struct device_node *idle_states)
-{
-	struct device_node *state_node;
-
-	for_each_child_of_node(idle_states, state_node) {
-		if ((!of_device_is_compatible(state_node, "arm,idle-state"))) {
-			pr_warn(" * %s: children of /cpus/idle-states must be \"arm,idle-state\" compatible\n",
-				     state_node->full_name);
-			continue;
-		}
-		/*
-		 * If memory allocation fails, better bail out.
-		 * Initialized nodes are freed at initialization
-		 * completion in of_init_idle_driver().
-		 */
-		if ((add_state_node(drv->cpumask, state_node) == -ENOMEM))
-			break;
-	}
-	/*
-	 * Sort the states list before initializing the CPUidle driver
-	 * states array.
-	 */
-	list_sort(NULL, &head, state_cmp);
-}
-
-/*
- * of_init_idle_driver - Parse the DT idle states and initialize the
- *			 idle driver states array
- *
- * @drv:	  Pointer to CPU idle driver to be initialized
- * @state_nodes:  Array of struct device_nodes to be initialized if
- *		  init_nodes == true. Must be sized CPUIDLE_STATE_MAX
- * @start_idx:    First idle state index to be initialized
- * @init_nodes:   Boolean to request device nodes initialization
- *
- * Returns:
- *	0 on success
- *	<0 on failure
- *
- *	On success the states array in the cpuidle driver contains
- *	initialized entries in the states array, starting from index start_idx.
- *	If init_nodes == true, on success the state_nodes array is initialized
- *	with idle state DT node pointers, starting from index start_idx,
- *	in a 1:1 relation with the idle driver states array.
- */
-int __init of_init_idle_driver(struct cpuidle_driver *drv,
-			       struct device_node *state_nodes[],
-			       unsigned int start_idx, bool init_nodes)
-{
-	struct device_node *idle_states_node;
-	int ret;
-
-	if (start_idx >= CPUIDLE_STATE_MAX) {
-		pr_warn("State index exceeds static CPU idle driver states array size\n");
-		return -EINVAL;
-	}
-
-	if (WARN(init_nodes && !state_nodes,
-		"Requested nodes stashing in an invalid nodes container\n"))
-		return -EINVAL;
-
-	idle_states_node = of_find_node_by_path("/cpus/idle-states");
-	if (!idle_states_node)
-		return -ENOENT;
-
-	add_idle_states(drv, idle_states_node);
-
-	ret = init_idle_states(drv, state_nodes, start_idx, init_nodes);
-
-	of_node_put(idle_states_node);
-
-	return ret;
-}
diff --git a/drivers/cpuidle/of_idle_states.h b/drivers/cpuidle/of_idle_states.h
deleted file mode 100644
index 049f94ff4428..000000000000
--- a/drivers/cpuidle/of_idle_states.h
+++ /dev/null
@@ -1,8 +0,0 @@
-#ifndef __OF_IDLE_STATES
-#define __OF_IDLE_STATES
-
-int __init of_init_idle_driver(struct cpuidle_driver *drv,
-			       struct device_node *state_nodes[],
-			       unsigned int start_idx,
-			       bool init_nodes);
-#endif