- 根目录:
- arch
- arm
- plat-omap
- include
- plat
- omap-pm.h
/*
* omap-pm.h - OMAP power management interface
*
* Copyright (C) 2008-2010 Texas Instruments, Inc.
* Copyright (C) 2008-2010 Nokia Corporation
* Paul Walmsley
*
* Interface developed by (in alphabetical order): Karthik Dasu, Jouni
* Högander, Tony Lindgren, Rajendra Nayak, Sakari Poussa,
* Veeramanikandan Raju, Anand Sawant, Igor Stoppa, Paul Walmsley,
* Richard Woodruff
*/
#ifndef ASM_ARM_ARCH_OMAP_OMAP_PM_H
#define ASM_ARM_ARCH_OMAP_OMAP_PM_H
#include <linux/device.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/opp.h>
/*
* agent_id values for use with omap_pm_set_min_bus_tput():
*
* OCP_INITIATOR_AGENT is only valid for devices that can act as
* initiators -- it represents the device's L3 interconnect
* connection. OCP_TARGET_AGENT represents the device's L4
* interconnect connection.
*/
#define OCP_TARGET_AGENT 1
#define OCP_INITIATOR_AGENT 2
/**
* omap_pm_if_early_init - OMAP PM init code called before clock fw init
* @mpu_opp_table: array ptr to struct omap_opp for MPU
* @dsp_opp_table: array ptr to struct omap_opp for DSP
* @l3_opp_table : array ptr to struct omap_opp for CORE
*
* Initialize anything that must be configured before the clock
* framework starts. The "_if_" is to avoid name collisions with the
* PM idle-loop code.
*/
int __init omap_pm_if_early_init(void);
/**
* omap_pm_if_init - OMAP PM init code called after clock fw init
*
* The main initialization code. OPP tables are passed in here. The
* "_if_" is to avoid name collisions with the PM idle-loop code.
*/
int __init omap_pm_if_init(void);
/**
* omap_pm_if_exit - OMAP PM exit code
*
* Exit code; currently unused. The "_if_" is to avoid name
* collisions with the PM idle-loop code.
*/
void omap_pm_if_exit(void);
/*
* Device-driver-originated constraints (via board-*.c files, platform_data)
*/
/**
* omap_pm_set_max_mpu_wakeup_lat - set the maximum MPU wakeup latency
* @dev: struct device * requesting the constraint
* @t: maximum MPU wakeup latency in microseconds
*
* Request that the maximum interrupt latency for the MPU to be no
* greater than @t microseconds. "Interrupt latency" in this case is
* defined as the elapsed time from the occurrence of a hardware or
* timer interrupt to the time when the device driver's interrupt
* service routine has been entered by the MPU.
*
* It is intended that underlying PM code will use this information to
* determine what power state to put the MPU powerdomain into, and
* possibly the CORE powerdomain as well, since interrupt handling
* code currently runs from SDRAM. Advanced PM or board*.c code may
* also configure interrupt controller priorities, OCP bus priorities,
* CPU speed(s), etc.
*
* This function will not affect device wakeup latency, e.g., time
* elapsed from when a device driver enables a hardware device with
* clk_enable(), to when the device is ready for register access or
* other use. To control this device wakeup latency, use
* omap_pm_set_max_dev_wakeup_lat()
*
* Multiple calls to omap_pm_set_max_mpu_wakeup_lat() will replace the
* previous t value. To remove the latency target for the MPU, call
* with t = -1.
*
* XXX This constraint will be deprecated soon in favor of the more
* general omap_pm_set_max_dev_wakeup_lat()
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t);
/**
* omap_pm_set_min_bus_tput - set minimum bus throughput needed by device
* @dev: struct device * requesting the constraint
* @tbus_id: interconnect to operate on (OCP_{INITIATOR,TARGET}_AGENT)
* @r: minimum throughput (in KiB/s)
*
* Request that the minimum data throughput on the OCP interconnect
* attached to device @dev interconnect agent @tbus_id be no less
* than @r KiB/s.
*
* It is expected that the OMAP PM or bus code will use this
* information to set the interconnect clock to run at the lowest
* possible speed that satisfies all current system users. The PM or
* bus code will adjust the estimate based on its model of the bus, so
* device driver authors should attempt to specify an accurate
* quantity for their device use case, and let the PM or bus code
* overestimate the numbers as necessary to handle request/response
* latency, other competing users on the system, etc. On OMAP2/3, if
* a driver requests a minimum L4 interconnect speed constraint, the
* code will also need to add an minimum L3 interconnect speed
* constraint,
*
* Multiple calls to omap_pm_set_min_bus_tput() will replace the
* previous rate value for this device. To remove the interconnect
* throughput restriction for this device, call with r = 0.
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r);
/**
* omap_pm_set_max_dev_wakeup_lat - set the maximum device enable latency
* @req_dev: struct device * requesting the constraint, or NULL if none
* @dev: struct device * to set the constraint one
* @t: maximum device wakeup latency in microseconds
*
* Request that the maximum amount of time necessary for a device @dev
* to become accessible after its clocks are enabled should be no
* greater than @t microseconds. Specifically, this represents the
* time from when a device driver enables device clocks with
* clk_enable(), to when the register reads and writes on the device
* will succeed. This function should be called before clk_disable()
* is called, since the power state transition decision may be made
* during clk_disable().
*
* It is intended that underlying PM code will use this information to
* determine what power state to put the powerdomain enclosing this
* device into.
*
* Multiple calls to omap_pm_set_max_dev_wakeup_lat() will replace the
* previous wakeup latency values for this device. To remove the
* wakeup latency restriction for this device, call with t = -1.
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_max_dev_wakeup_lat(struct device *req_dev, struct device *dev,
long t);
/**
* omap_pm_set_max_sdma_lat - set the maximum system DMA transfer start latency
* @dev: struct device *
* @t: maximum DMA transfer start latency in microseconds
*
* Request that the maximum system DMA transfer start latency for this
* device 'dev' should be no greater than 't' microseconds. "DMA
* transfer start latency" here is defined as the elapsed time from
* when a device (e.g., McBSP) requests that a system DMA transfer
* start or continue, to the time at which data starts to flow into
* that device from the system DMA controller.
*
* It is intended that underlying PM code will use this information to
* determine what power state to put the CORE powerdomain into.
*
* Since system DMA transfers may not involve the MPU, this function
* will not affect MPU wakeup latency. Use set_max_cpu_lat() to do
* so. Similarly, this function will not affect device wakeup latency
* -- use set_max_dev_wakeup_lat() to affect that.
*
* Multiple calls to set_max_sdma_lat() will replace the previous t
* value for this device. To remove the maximum DMA latency for this
* device, call with t = -1.
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_max_sdma_lat(struct device *dev, long t);
/**
* omap_pm_set_min_clk_rate - set minimum clock rate requested by @dev
* @dev: struct device * requesting the constraint
* @clk: struct clk * to set the minimum rate constraint on
* @r: minimum rate in Hz
*
* Request that the minimum clock rate on the device @dev's clk @clk
* be no less than @r Hz.
*
* It is expected that the OMAP PM code will use this information to
* find an OPP or clock setting that will satisfy this clock rate
* constraint, along with any other applicable system constraints on
* the clock rate or corresponding voltage, etc.
*
* omap_pm_set_min_clk_rate() differs from the clock code's
* clk_set_rate() in that it considers other constraints before taking
* any hardware action, and may change a system OPP rather than just a
* clock rate. clk_set_rate() is intended to be a low-level
* interface.
*
* omap_pm_set_min_clk_rate() is easily open to abuse. A better API
* would be something like "omap_pm_set_min_dev_performance()";
* however, there is no easily-generalizable concept of performance
* that applies to all devices. Only a device (and possibly the
* device subsystem) has both the subsystem-specific knowledge, and
* the hardware IP block-specific knowledge, to translate a constraint
* on "touchscreen sampling accuracy" or "number of pixels or polygons
* rendered per second" to a clock rate. This translation can be
* dependent on the hardware IP block's revision, or firmware version,
* and the driver is the only code on the system that has this
* information and can know how to translate that into a clock rate.
*
* The intended use-case for this function is for userspace or other
* kernel code to communicate a particular performance requirement to
* a subsystem; then for the subsystem to communicate that requirement
* to something that is meaningful to the device driver; then for the
* device driver to convert that requirement to a clock rate, and to
* then call omap_pm_set_min_clk_rate().
*
* Users of this function (such as device drivers) should not simply
* call this function with some high clock rate to ensure "high
* performance." Rather, the device driver should take a performance
* constraint from its subsystem, such as "render at least X polygons
* per second," and use some formula or table to convert that into a
* clock rate constraint given the hardware type and hardware
* revision. Device drivers or subsystems should not assume that they
* know how to make a power/performance tradeoff - some device use
* cases may tolerate a lower-fidelity device function for lower power
* consumption; others may demand a higher-fidelity device function,
* no matter what the power consumption.
*
* Multiple calls to omap_pm_set_min_clk_rate() will replace the
* previous rate value for the device @dev. To remove the minimum clock
* rate constraint for the device, call with r = 0.
*
* Returns -EINVAL for an invalid argument, -ERANGE if the constraint
* is not satisfiable, or 0 upon success.
*/
int omap_pm_set_min_clk_rate(struct device *dev, struct clk *c, long r);
/*
* DSP Bridge-specific constraints
*/
/**
* omap_pm_dsp_get_opp_table - get OPP->DSP clock frequency table
*
* Intended for use by DSPBridge. Returns an array of OPP->DSP clock
* frequency entries. The final item in the array should have .rate =
* .opp_id = 0.
*/
const struct omap_opp *omap_pm_dsp_get_opp_table(void);
/**
* omap_pm_dsp_set_min_opp - receive desired OPP target ID from DSP Bridge
* @opp_id: target DSP OPP ID
*
* Set a minimum OPP ID for the DSP. This is intended to be called
* only from the DSP Bridge MPU-side driver. Unfortunately, the only
* information that code receives from the DSP/BIOS load estimator is the
* target OPP ID; hence, this interface. No return value.
*/
void omap_pm_dsp_set_min_opp(u8 opp_id);
/**
* omap_pm_dsp_get_opp - report the current DSP OPP ID
*
* Report the current OPP for the DSP. Since on OMAP3, the DSP and
* MPU share a single voltage domain, the OPP ID returned back may
* represent a higher DSP speed than the OPP requested via
* omap_pm_dsp_set_min_opp().
*
* Returns the current VDD1 OPP ID, or 0 upon error.
*/
u8 omap_pm_dsp_get_opp(void);
/*
* CPUFreq-originated constraint
*
* In the future, this should be handled by custom OPP clocktype
* functions.
*/
/**
* omap_pm_cpu_get_freq_table - return a cpufreq_frequency_table array ptr
*
* Provide a frequency table usable by CPUFreq for the current chip/board.
* Returns a pointer to a struct cpufreq_frequency_table array or NULL
* upon error.
*/
struct cpufreq_frequency_table **omap_pm_cpu_get_freq_table(void);
/**
* omap_pm_cpu_set_freq - set the current minimum MPU frequency
* @f: MPU frequency in Hz
*
* Set the current minimum CPU frequency. The actual CPU frequency
* used could end up higher if the DSP requested a higher OPP.
* Intended to be called by plat-omap/cpu_omap.c:omap_target(). No
* return value.
*/
void omap_pm_cpu_set_freq(unsigned long f);
/**
* omap_pm_cpu_get_freq - report the current CPU frequency
*
* Returns the current MPU frequency, or 0 upon error.
*/
unsigned long omap_pm_cpu_get_freq(void);
/*
* Device context loss tracking
*/
/**
* omap_pm_get_dev_context_loss_count - return count of times dev has lost ctx
* @dev: struct device *
*
* This function returns the number of times that the device @dev has
* lost its internal context. This generally occurs on a powerdomain
* transition to OFF. Drivers use this as an optimization to avoid restoring
* context if the device hasn't lost it. To use, drivers should initially
* call this in their context save functions and store the result. Early in
* the driver's context restore function, the driver should call this function
* again, and compare the result to the stored counter. If they differ, the
* driver must restore device context. If the number of context losses
* exceeds the maximum positive integer, the function will wrap to 0 and
* continue counting. Returns the number of context losses for this device,
* or negative value upon error.
*/
int omap_pm_get_dev_context_loss_count(struct device *dev);
void omap_pm_enable_off_mode(void);
void omap_pm_disable_off_mode(void);
#endif