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+/*
+ * 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
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