Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 1 | /* |
| 2 | * Generic OPP Interface |
| 3 | * |
| 4 | * Copyright (C) 2009-2010 Texas Instruments Incorporated. |
| 5 | * Nishanth Menon |
| 6 | * Romit Dasgupta |
| 7 | * Kevin Hilman |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | */ |
| 13 | |
| 14 | #ifndef __DRIVER_OPP_H__ |
| 15 | #define __DRIVER_OPP_H__ |
| 16 | |
| 17 | #include <linux/device.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/list.h> |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 20 | #include <linux/limits.h> |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 21 | #include <linux/pm_opp.h> |
| 22 | #include <linux/rculist.h> |
| 23 | #include <linux/rcupdate.h> |
| 24 | |
Viresh Kumar | 87b4115 | 2015-11-05 14:21:19 +0530 | [diff] [blame] | 25 | /* Lock to allow exclusive modification to the device and opp lists */ |
| 26 | extern struct mutex dev_opp_list_lock; |
| 27 | |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 28 | /* |
| 29 | * Internal data structure organization with the OPP layer library is as |
| 30 | * follows: |
| 31 | * dev_opp_list (root) |
| 32 | * |- device 1 (represents voltage domain 1) |
| 33 | * | |- opp 1 (availability, freq, voltage) |
| 34 | * | |- opp 2 .. |
| 35 | * ... ... |
| 36 | * | `- opp n .. |
| 37 | * |- device 2 (represents the next voltage domain) |
| 38 | * ... |
| 39 | * `- device m (represents mth voltage domain) |
| 40 | * device 1, 2.. are represented by dev_opp structure while each opp |
| 41 | * is represented by the opp structure. |
| 42 | */ |
| 43 | |
| 44 | /** |
| 45 | * struct dev_pm_opp - Generic OPP description structure |
| 46 | * @node: opp list node. The nodes are maintained throughout the lifetime |
| 47 | * of boot. It is expected only an optimal set of OPPs are |
| 48 | * added to the library by the SoC framework. |
| 49 | * RCU usage: opp list is traversed with RCU locks. node |
| 50 | * modification is possible realtime, hence the modifications |
| 51 | * are protected by the dev_opp_list_lock for integrity. |
| 52 | * IMPORTANT: the opp nodes should be maintained in increasing |
| 53 | * order. |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 54 | * @available: true/false - marks if this OPP as available or not |
Viresh Kumar | dc4e7b1 | 2015-11-19 09:13:56 +0530 | [diff] [blame] | 55 | * @dynamic: not-created from static DT entries. |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 56 | * @turbo: true if turbo (boost) OPP |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 57 | * @suspend: true if suspend OPP |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 58 | * @rate: Frequency in hertz |
| 59 | * @u_volt: Target voltage in microvolts corresponding to this OPP |
| 60 | * @u_volt_min: Minimum voltage in microvolts corresponding to this OPP |
| 61 | * @u_volt_max: Maximum voltage in microvolts corresponding to this OPP |
| 62 | * @u_amp: Maximum current drawn by the device in microamperes |
| 63 | * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's |
| 64 | * frequency from any other OPP's frequency. |
| 65 | * @dev_opp: points back to the device_opp struct this opp belongs to |
| 66 | * @rcu_head: RCU callback head used for deferred freeing |
| 67 | * @np: OPP's device node. |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 68 | * @dentry: debugfs dentry pointer (per opp) |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 69 | * |
| 70 | * This structure stores the OPP information for a given device. |
| 71 | */ |
| 72 | struct dev_pm_opp { |
| 73 | struct list_head node; |
| 74 | |
| 75 | bool available; |
| 76 | bool dynamic; |
| 77 | bool turbo; |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 78 | bool suspend; |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 79 | unsigned long rate; |
| 80 | |
| 81 | unsigned long u_volt; |
| 82 | unsigned long u_volt_min; |
| 83 | unsigned long u_volt_max; |
| 84 | unsigned long u_amp; |
| 85 | unsigned long clock_latency_ns; |
| 86 | |
| 87 | struct device_opp *dev_opp; |
| 88 | struct rcu_head rcu_head; |
| 89 | |
| 90 | struct device_node *np; |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 91 | |
| 92 | #ifdef CONFIG_DEBUG_FS |
| 93 | struct dentry *dentry; |
| 94 | #endif |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 95 | }; |
| 96 | |
| 97 | /** |
| 98 | * struct device_list_opp - devices managed by 'struct device_opp' |
| 99 | * @node: list node |
| 100 | * @dev: device to which the struct object belongs |
| 101 | * @rcu_head: RCU callback head used for deferred freeing |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 102 | * @dentry: debugfs dentry pointer (per device) |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 103 | * |
| 104 | * This is an internal data structure maintaining the list of devices that are |
| 105 | * managed by 'struct device_opp'. |
| 106 | */ |
| 107 | struct device_list_opp { |
| 108 | struct list_head node; |
| 109 | const struct device *dev; |
| 110 | struct rcu_head rcu_head; |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 111 | |
| 112 | #ifdef CONFIG_DEBUG_FS |
| 113 | struct dentry *dentry; |
| 114 | #endif |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 115 | }; |
| 116 | |
| 117 | /** |
| 118 | * struct device_opp - Device opp structure |
| 119 | * @node: list node - contains the devices with OPPs that |
| 120 | * have been registered. Nodes once added are not modified in this |
| 121 | * list. |
| 122 | * RCU usage: nodes are not modified in the list of device_opp, |
| 123 | * however addition is possible and is secured by dev_opp_list_lock |
| 124 | * @srcu_head: notifier head to notify the OPP availability changes. |
| 125 | * @rcu_head: RCU callback head used for deferred freeing |
| 126 | * @dev_list: list of devices that share these OPPs |
| 127 | * @opp_list: list of opps |
| 128 | * @np: struct device_node pointer for opp's DT node. |
Viresh Kumar | dc4e7b1 | 2015-11-19 09:13:56 +0530 | [diff] [blame] | 129 | * @clock_latency_ns_max: Max clock latency in nanoseconds. |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 130 | * @shared_opp: OPP is shared between multiple devices. |
Viresh Kumar | dc4e7b1 | 2015-11-19 09:13:56 +0530 | [diff] [blame] | 131 | * @suspend_opp: Pointer to OPP to be used during device suspend. |
Viresh Kumar | 7de36b0 | 2015-12-09 08:01:46 +0530 | [diff] [blame^] | 132 | * @supported_hw: Array of version number to support. |
| 133 | * @supported_hw_count: Number of elements in supported_hw array. |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 134 | * @dentry: debugfs dentry pointer of the real device directory (not links). |
| 135 | * @dentry_name: Name of the real dentry. |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 136 | * |
| 137 | * This is an internal data structure maintaining the link to opps attached to |
| 138 | * a device. This structure is not meant to be shared to users as it is |
| 139 | * meant for book keeping and private to OPP library. |
| 140 | * |
| 141 | * Because the opp structures can be used from both rcu and srcu readers, we |
| 142 | * need to wait for the grace period of both of them before freeing any |
| 143 | * resources. And so we have used kfree_rcu() from within call_srcu() handlers. |
| 144 | */ |
| 145 | struct device_opp { |
| 146 | struct list_head node; |
| 147 | |
| 148 | struct srcu_notifier_head srcu_head; |
| 149 | struct rcu_head rcu_head; |
| 150 | struct list_head dev_list; |
| 151 | struct list_head opp_list; |
| 152 | |
| 153 | struct device_node *np; |
| 154 | unsigned long clock_latency_ns_max; |
| 155 | bool shared_opp; |
| 156 | struct dev_pm_opp *suspend_opp; |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 157 | |
Viresh Kumar | 7de36b0 | 2015-12-09 08:01:46 +0530 | [diff] [blame^] | 158 | unsigned int *supported_hw; |
| 159 | unsigned int supported_hw_count; |
| 160 | |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 161 | #ifdef CONFIG_DEBUG_FS |
| 162 | struct dentry *dentry; |
| 163 | char dentry_name[NAME_MAX]; |
| 164 | #endif |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 165 | }; |
| 166 | |
| 167 | /* Routines internal to opp core */ |
| 168 | struct device_opp *_find_device_opp(struct device *dev); |
| 169 | struct device_list_opp *_add_list_dev(const struct device *dev, |
| 170 | struct device_opp *dev_opp); |
| 171 | struct device_node *_of_get_opp_desc_node(struct device *dev); |
| 172 | |
Viresh Kumar | deaa514 | 2015-11-11 07:59:01 +0530 | [diff] [blame] | 173 | #ifdef CONFIG_DEBUG_FS |
| 174 | void opp_debug_remove_one(struct dev_pm_opp *opp); |
| 175 | int opp_debug_create_one(struct dev_pm_opp *opp, struct device_opp *dev_opp); |
| 176 | int opp_debug_register(struct device_list_opp *list_dev, |
| 177 | struct device_opp *dev_opp); |
| 178 | void opp_debug_unregister(struct device_list_opp *list_dev, |
| 179 | struct device_opp *dev_opp); |
| 180 | #else |
| 181 | static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {} |
| 182 | |
| 183 | static inline int opp_debug_create_one(struct dev_pm_opp *opp, |
| 184 | struct device_opp *dev_opp) |
| 185 | { return 0; } |
| 186 | static inline int opp_debug_register(struct device_list_opp *list_dev, |
| 187 | struct device_opp *dev_opp) |
| 188 | { return 0; } |
| 189 | |
| 190 | static inline void opp_debug_unregister(struct device_list_opp *list_dev, |
| 191 | struct device_opp *dev_opp) |
| 192 | { } |
| 193 | #endif /* DEBUG_FS */ |
| 194 | |
Viresh Kumar | f59d3ee | 2015-09-04 13:47:26 +0530 | [diff] [blame] | 195 | #endif /* __DRIVER_OPP_H__ */ |