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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * omap-pm-noop.c - OMAP power management interface - dummy version
   4  *
   5  * This code implements the OMAP power management interface to
   6  * drivers, CPUIdle, CPUFreq, and DSP Bridge.  It is strictly for
   7  * debug/demonstration use, as it does nothing but printk() whenever a
   8  * function is called (when DEBUG is defined, below)
   9  *
  10  * Copyright (C) 2008-2009 Texas Instruments, Inc.
  11  * Copyright (C) 2008-2009 Nokia Corporation
  12  * Paul Walmsley
  13  *
  14  * Interface developed by (in alphabetical order):
  15  * Karthik Dasu, Tony Lindgren, Rajendra Nayak, Sakari Poussa, Veeramanikandan
  16  * Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, Richard Woodruff
  17  */
  18
  19 #undef DEBUG
  20
  21 #include <linux/init.h>
  22 #include <linux/cpufreq.h>
  23 #include <linux/device.h>
  24 #include <linux/platform_device.h>
  25
  26 #include "omap_device.h"
  27 #include "omap-pm.h"
  28
  29 static bool off_mode_enabled;
  30 static int dummy_context_loss_counter;
  31
  32 /*
  33  * Device-driver-originated constraints (via board-*.c files)
  34  */
  35
  36 int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t)
  37 {
  38         if (!dev || t < -1) {
  39                 WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
  40                 return -EINVAL;
  41         }
  42
  43         if (t == -1)
  44                 pr_debug("OMAP PM: remove max MPU wakeup latency constraint: dev %s\n",
  45                          dev_name(dev));
  46         else
  47                 pr_debug("OMAP PM: add max MPU wakeup latency constraint: dev %s, t = %ld usec\n",
  48                          dev_name(dev), t);
  49
  50         /*
  51          * For current Linux, this needs to map the MPU to a
  52          * powerdomain, then go through the list of current max lat
  53          * constraints on the MPU and find the smallest.  If
  54          * the latency constraint has changed, the code should
  55          * recompute the state to enter for the next powerdomain
  56          * state.
  57          *
  58          * TI CDP code can call constraint_set here.
  59          */
  60
  61         return 0;
  62 }
  63
  64 int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r)
  65 {
  66         if (!dev || (agent_id != OCP_INITIATOR_AGENT &&
  67             agent_id != OCP_TARGET_AGENT)) {
  68                 WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
  69                 return -EINVAL;
  70         }
  71
  72         if (r == 0)
  73                 pr_debug("OMAP PM: remove min bus tput constraint: dev %s for agent_id %d\n",
  74                          dev_name(dev), agent_id);
  75         else
  76                 pr_debug("OMAP PM: add min bus tput constraint: dev %s for agent_id %d: rate %ld KiB\n",
  77                          dev_name(dev), agent_id, r);
  78
  79         /*
  80          * This code should model the interconnect and compute the
  81          * required clock frequency, convert that to a VDD2 OPP ID, then
  82          * set the VDD2 OPP appropriately.
  83          *
  84          * TI CDP code can call constraint_set here on the VDD2 OPP.
  85          */
  86
  87         return 0;
  88 }
  89
  90 /*
  91  * DSP Bridge-specific constraints
  92  */
  93
  94
  95 /**
  96  * omap_pm_enable_off_mode - notify OMAP PM that off-mode is enabled
  97  *
  98  * Intended for use only by OMAP PM core code to notify this layer
  99  * that off mode has been enabled.
 100  */
 101 void omap_pm_enable_off_mode(void)
 102 {
 103         off_mode_enabled = true;
 104 }
 105
 106 /**
 107  * omap_pm_disable_off_mode - notify OMAP PM that off-mode is disabled
 108  *
 109  * Intended for use only by OMAP PM core code to notify this layer
 110  * that off mode has been disabled.
 111  */
 112 void omap_pm_disable_off_mode(void)
 113 {
 114         off_mode_enabled = false;
 115 }
 116
 117 /*
 118  * Device context loss tracking
 119  */
 120
 121 #ifdef CONFIG_ARCH_OMAP2PLUS
 122
 123 int omap_pm_get_dev_context_loss_count(struct device *dev)
 124 {
 125         struct platform_device *pdev = to_platform_device(dev);
 126         int count;
 127
 128         if (WARN_ON(!dev))
 129                 return -ENODEV;
 130
 131         if (dev->pm_domain == &omap_device_pm_domain) {
 132                 count = omap_device_get_context_loss_count(pdev);
 133         } else {
 134                 WARN_ONCE(off_mode_enabled, "omap_pm: using dummy context loss counter; device %s should be converted to omap_device",
 135                           dev_name(dev));
 136
 137                 count = dummy_context_loss_counter;
 138
 139                 if (off_mode_enabled) {
 140                         count++;
 141                         /*
 142                          * Context loss count has to be a non-negative value.
 143                          * Clear the sign bit to get a value range from 0 to
 144                          * INT_MAX.
 145                          */
 146                         count &= INT_MAX;
 147                         dummy_context_loss_counter = count;
 148                 }
 149         }
 150
 151         pr_debug("OMAP PM: context loss count for dev %s = %d\n",
 152                  dev_name(dev), count);
 153
 154         return count;
 155 }
 156
 157 #else
 158
 159 int omap_pm_get_dev_context_loss_count(struct device *dev)
 160 {
 161         return dummy_context_loss_counter;
 162 }
 163
 164 #endif
 165
 166 /* Should be called before clk framework init */
 167 int __init omap_pm_if_early_init(void)
 168 {
 169         return 0;
 170 }
 171
 172 /* Must be called after clock framework is initialized */
 173 int __init omap_pm_if_init(void)
 174 {
 175         return 0;
 176 }