arch/arm/mach-omap2/omap-pm-noop.c

   1 /*
   2  * omap-pm-noop.c - OMAP power management interface - dummy version
   3  *
   4  * This code implements the OMAP power management interface to
   5  * drivers, CPUIdle, CPUFreq, and DSP Bridge.  It is strictly for
   6  * debug/demonstration use, as it does nothing but printk() whenever a
   7  * function is called (when DEBUG is defined, below)
   8  *
   9  * Copyright (C) 2008-2009 Texas Instruments, Inc.
  10  * Copyright (C) 2008-2009 Nokia Corporation
  11  * Paul Walmsley
  12  *
  13  * Interface developed by (in alphabetical order):
  14  * Karthik Dasu, Tony Lindgren, Rajendra Nayak, Sakari Poussa, Veeramanikandan
  15  * Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, Richard Woodruff
  16  */
  17
  18 #undef DEBUG
  19
  20 #include <linux/init.h>
  21 #include <linux/cpufreq.h>
  22 #include <linux/device.h>
  23 #include <linux/platform_device.h>
  24
  25 #include "omap_device.h"
  26 #include "omap-pm.h"
  27
  28 static bool off_mode_enabled;
  29 static int dummy_context_loss_counter;
  30
  31 /*
  32  * Device-driver-originated constraints (via board-*.c files)
  33  */
  34
  35 int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t)
  36 {
  37         if (!dev || t < -1) {
  38                 WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
  39                 return -EINVAL;
  40         }
  41
  42         if (t == -1)
  43                 pr_debug("OMAP PM: remove max MPU wakeup latency constraint: dev %s\n",
  44                          dev_name(dev));
  45         else
  46                 pr_debug("OMAP PM: add max MPU wakeup latency constraint: dev %s, t = %ld usec\n",
  47                          dev_name(dev), t);
  48
  49         /*
  50          * For current Linux, this needs to map the MPU to a
  51          * powerdomain, then go through the list of current max lat
  52          * constraints on the MPU and find the smallest.  If
  53          * the latency constraint has changed, the code should
  54          * recompute the state to enter for the next powerdomain
  55          * state.
  56          *
  57          * TI CDP code can call constraint_set here.
  58          */
  59
  60         return 0;
  61 }
  62
  63 int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r)
  64 {
  65         if (!dev || (agent_id != OCP_INITIATOR_AGENT &&
  66             agent_id != OCP_TARGET_AGENT)) {
  67                 WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
  68                 return -EINVAL;
  69         }
  70
  71         if (r == 0)
  72                 pr_debug("OMAP PM: remove min bus tput constraint: dev %s for agent_id %d\n",
  73                          dev_name(dev), agent_id);
  74         else
  75                 pr_debug("OMAP PM: add min bus tput constraint: dev %s for agent_id %d: rate %ld KiB\n",
  76                          dev_name(dev), agent_id, r);
  77
  78         /*
  79          * This code should model the interconnect and compute the
  80          * required clock frequency, convert that to a VDD2 OPP ID, then
  81          * set the VDD2 OPP appropriately.
  82          *
  83          * TI CDP code can call constraint_set here on the VDD2 OPP.
  84          */
  85
  86         return 0;
  87 }
  88
  89 /*
  90  * DSP Bridge-specific constraints
  91  */
  92
  93
  94 /**
  95  * omap_pm_enable_off_mode - notify OMAP PM that off-mode is enabled
  96  *
  97  * Intended for use only by OMAP PM core code to notify this layer
  98  * that off mode has been enabled.
  99  */
 100 void omap_pm_enable_off_mode(void)
 101 {
 102         off_mode_enabled = true;
 103 }
 104
 105 /**
 106  * omap_pm_disable_off_mode - notify OMAP PM that off-mode is disabled
 107  *
 108  * Intended for use only by OMAP PM core code to notify this layer
 109  * that off mode has been disabled.
 110  */
 111 void omap_pm_disable_off_mode(void)
 112 {
 113         off_mode_enabled = false;
 114 }
 115
 116 /*
 117  * Device context loss tracking
 118  */
 119
 120 #ifdef CONFIG_ARCH_OMAP2PLUS
 121
 122 int omap_pm_get_dev_context_loss_count(struct device *dev)
 123 {
 124         struct platform_device *pdev = to_platform_device(dev);
 125         int count;
 126
 127         if (WARN_ON(!dev))
 128                 return -ENODEV;
 129
 130         if (dev->pm_domain == &omap_device_pm_domain) {
 131                 count = omap_device_get_context_loss_count(pdev);
 132         } else {
 133                 WARN_ONCE(off_mode_enabled, "omap_pm: using dummy context loss counter; device %s should be converted to omap_device",
 134                           dev_name(dev));
 135
 136                 count = dummy_context_loss_counter;
 137
 138                 if (off_mode_enabled) {
 139                         count++;
 140                         /*
 141                          * Context loss count has to be a non-negative value.
 142                          * Clear the sign bit to get a value range from 0 to
 143                          * INT_MAX.
 144                          */
 145                         count &= INT_MAX;
 146                         dummy_context_loss_counter = count;
 147                 }
 148         }
 149
 150         pr_debug("OMAP PM: context loss count for dev %s = %d\n",
 151                  dev_name(dev), count);
 152
 153         return count;
 154 }
 155
 156 #else
 157
 158 int omap_pm_get_dev_context_loss_count(struct device *dev)
 159 {
 160         return dummy_context_loss_counter;
 161 }
 162
 163 #endif
 164
 165 /* Should be called before clk framework init */
 166 int __init omap_pm_if_early_init(void)
 167 {
 168         return 0;
 169 }
 170
 171 /* Must be called after clock framework is initialized */
 172 int __init omap_pm_if_init(void)
 173 {
 174         return 0;
 175 }