arch/arm/mach-omap2/omap-pm.h

   1 /*
   2  * omap-pm.h - OMAP power management interface
   3  *
   4  * Copyright (C) 2008-2010 Texas Instruments, Inc.
   5  * Copyright (C) 2008-2010 Nokia Corporation
   6  * Paul Walmsley
   7  *
   8  * Interface developed by (in alphabetical order): Karthik Dasu, Jouni
   9  * Högander, Tony Lindgren, Rajendra Nayak, Sakari Poussa,
  10  * Veeramanikandan Raju, Anand Sawant, Igor Stoppa, Paul Walmsley,
  11  * Richard Woodruff
  12  */
  13
  14 #ifndef ASM_ARM_ARCH_OMAP_OMAP_PM_H
  15 #define ASM_ARM_ARCH_OMAP_OMAP_PM_H
  16
  17 #include <linux/device.h>
  18 #include <linux/cpufreq.h>
  19 #include <linux/clk.h>
  20 #include <linux/pm_opp.h>
  21
  22 /*
  23  * agent_id values for use with omap_pm_set_min_bus_tput():
  24  *
  25  * OCP_INITIATOR_AGENT is only valid for devices that can act as
  26  * initiators -- it represents the device's L3 interconnect
  27  * connection.  OCP_TARGET_AGENT represents the device's L4
  28  * interconnect connection.
  29  */
  30 #define OCP_TARGET_AGENT                1
  31 #define OCP_INITIATOR_AGENT             2
  32
  33 /**
  34  * omap_pm_if_early_init - OMAP PM init code called before clock fw init
  35  * @mpu_opp_table: array ptr to struct omap_opp for MPU
  36  * @dsp_opp_table: array ptr to struct omap_opp for DSP
  37  * @l3_opp_table : array ptr to struct omap_opp for CORE
  38  *
  39  * Initialize anything that must be configured before the clock
  40  * framework starts.  The "_if_" is to avoid name collisions with the
  41  * PM idle-loop code.
  42  */
  43 int __init omap_pm_if_early_init(void);
  44
  45 /**
  46  * omap_pm_if_init - OMAP PM init code called after clock fw init
  47  *
  48  * The main initialization code.  OPP tables are passed in here.  The
  49  * "_if_" is to avoid name collisions with the PM idle-loop code.
  50  */
  51 int __init omap_pm_if_init(void);
  52
  53 /*
  54  * Device-driver-originated constraints (via board-*.c files, platform_data)
  55  */
  56
  57
  58 /**
  59  * omap_pm_set_max_mpu_wakeup_lat - set the maximum MPU wakeup latency
  60  * @dev: struct device * requesting the constraint
  61  * @t: maximum MPU wakeup latency in microseconds
  62  *
  63  * Request that the maximum interrupt latency for the MPU to be no
  64  * greater than @t microseconds. "Interrupt latency" in this case is
  65  * defined as the elapsed time from the occurrence of a hardware or
  66  * timer interrupt to the time when the device driver's interrupt
  67  * service routine has been entered by the MPU.
  68  *
  69  * It is intended that underlying PM code will use this information to
  70  * determine what power state to put the MPU powerdomain into, and
  71  * possibly the CORE powerdomain as well, since interrupt handling
  72  * code currently runs from SDRAM.  Advanced PM or board*.c code may
  73  * also configure interrupt controller priorities, OCP bus priorities,
  74  * CPU speed(s), etc.
  75  *
  76  * This function will not affect device wakeup latency, e.g., time
  77  * elapsed from when a device driver enables a hardware device with
  78  * clk_enable(), to when the device is ready for register access or
  79  * other use.  To control this device wakeup latency, use
  80  * omap_pm_set_max_dev_wakeup_lat()
  81  *
  82  * Multiple calls to omap_pm_set_max_mpu_wakeup_lat() will replace the
  83  * previous t value.  To remove the latency target for the MPU, call
  84  * with t = -1.
  85  *
  86  * XXX This constraint will be deprecated soon in favor of the more
  87  * general omap_pm_set_max_dev_wakeup_lat()
  88  *
  89  * Returns -EINVAL for an invalid argument, -ERANGE if the constraint
  90  * is not satisfiable, or 0 upon success.
  91  */
  92 int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t);
  93
  94
  95 /**
  96  * omap_pm_set_min_bus_tput - set minimum bus throughput needed by device
  97  * @dev: struct device * requesting the constraint
  98  * @tbus_id: interconnect to operate on (OCP_{INITIATOR,TARGET}_AGENT)
  99  * @r: minimum throughput (in KiB/s)
 100  *
 101  * Request that the minimum data throughput on the OCP interconnect
 102  * attached to device @dev interconnect agent @tbus_id be no less
 103  * than @r KiB/s.
 104  *
 105  * It is expected that the OMAP PM or bus code will use this
 106  * information to set the interconnect clock to run at the lowest
 107  * possible speed that satisfies all current system users.  The PM or
 108  * bus code will adjust the estimate based on its model of the bus, so
 109  * device driver authors should attempt to specify an accurate
 110  * quantity for their device use case, and let the PM or bus code
 111  * overestimate the numbers as necessary to handle request/response
 112  * latency, other competing users on the system, etc.  On OMAP2/3, if
 113  * a driver requests a minimum L4 interconnect speed constraint, the
 114  * code will also need to add an minimum L3 interconnect speed
 115  * constraint,
 116  *
 117  * Multiple calls to omap_pm_set_min_bus_tput() will replace the
 118  * previous rate value for this device.  To remove the interconnect
 119  * throughput restriction for this device, call with r = 0.
 120  *
 121  * Returns -EINVAL for an invalid argument, -ERANGE if the constraint
 122  * is not satisfiable, or 0 upon success.
 123  */
 124 int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r);
 125
 126
 127 /*
 128  * CPUFreq-originated constraint
 129  *
 130  * In the future, this should be handled by custom OPP clocktype
 131  * functions.
 132  */
 133
 134
 135 /*
 136  * Device context loss tracking
 137  */
 138
 139 /**
 140  * omap_pm_get_dev_context_loss_count - return count of times dev has lost ctx
 141  * @dev: struct device *
 142  *
 143  * This function returns the number of times that the device @dev has
 144  * lost its internal context.  This generally occurs on a powerdomain
 145  * transition to OFF.  Drivers use this as an optimization to avoid restoring
 146  * context if the device hasn't lost it.  To use, drivers should initially
 147  * call this in their context save functions and store the result.  Early in
 148  * the driver's context restore function, the driver should call this function
 149  * again, and compare the result to the stored counter.  If they differ, the
 150  * driver must restore device context.   If the number of context losses
 151  * exceeds the maximum positive integer, the function will wrap to 0 and
 152  * continue counting.  Returns the number of context losses for this device,
 153  * or negative value upon error.
 154  */
 155 int omap_pm_get_dev_context_loss_count(struct device *dev);
 156
 157 void omap_pm_enable_off_mode(void);
 158 void omap_pm_disable_off_mode(void);
 159
 160 #endif