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
 28static bool off_mode_enabled;
 29static int dummy_context_loss_counter;
 30
 31/*
 32 * Device-driver-originated constraints (via board-*.c files)
 33 */
 34
 35int 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
 63int 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 */
100void 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 */
111void 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
122int 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
158int 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 */
166int __init omap_pm_if_early_init(void)
167{
168	return 0;
169}
170
171/* Must be called after clock framework is initialized */
172int __init omap_pm_if_init(void)
173{
174	return 0;
175}