linux/arch/arm/plat-omap/omap-pm-noop.c

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/*
* omap-pm-noop.c - OMAP power management interface - dummy version
*
* This code implements the OMAP power management interface to
* drivers, CPUIdle, CPUFreq, and DSP Bridge. It is strictly for
* debug/demonstration use, as it does nothing but printk() whenever a
* function is called (when DEBUG is defined, below)
*
* Copyright (C) 2008-2009 Texas Instruments, Inc.
* Copyright (C) 2008-2009 Nokia Corporation
* Paul Walmsley
*
* Interface developed by (in alphabetical order):
* Karthik Dasu, Tony Lindgren, Rajendra Nayak, Sakari Poussa, Veeramanikandan
* Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, Richard Woodruff
*/
#undef DEBUG
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/device.h>
#include <linux/platform_device.h>
/* Interface documentation is in mach/omap-pm.h */
#include <plat/omap-pm.h>
#include <plat/omap_device.h>
static bool off_mode_enabled;
static int dummy_context_loss_counter;
/*
* Device-driver-originated constraints (via board-*.c files)
*/
int omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t)
{
if (!dev || t < -1) {
WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
return -EINVAL;
}
if (t == -1)
pr_debug("OMAP PM: remove max MPU wakeup latency constraint: dev %s\n",
dev_name(dev));
else
pr_debug("OMAP PM: add max MPU wakeup latency constraint: dev %s, t = %ld usec\n",
dev_name(dev), t);
/*
* For current Linux, this needs to map the MPU to a
* powerdomain, then go through the list of current max lat
* constraints on the MPU and find the smallest. If
* the latency constraint has changed, the code should
* recompute the state to enter for the next powerdomain
* state.
*
* TI CDP code can call constraint_set here.
*/
return 0;
}
int omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r)
{
if (!dev || (agent_id != OCP_INITIATOR_AGENT &&
agent_id != OCP_TARGET_AGENT)) {
WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
return -EINVAL;
}
if (r == 0)
pr_debug("OMAP PM: remove min bus tput constraint: dev %s for agent_id %d\n",
dev_name(dev), agent_id);
else
pr_debug("OMAP PM: add min bus tput constraint: dev %s for agent_id %d: rate %ld KiB\n",
dev_name(dev), agent_id, r);
/*
* This code should model the interconnect and compute the
* required clock frequency, convert that to a VDD2 OPP ID, then
* set the VDD2 OPP appropriately.
*
* TI CDP code can call constraint_set here on the VDD2 OPP.
*/
return 0;
}
int omap_pm_set_max_dev_wakeup_lat(struct device *req_dev, struct device *dev,
long t)
{
if (!req_dev || !dev || t < -1) {
WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
return -EINVAL;
}
if (t == -1)
pr_debug("OMAP PM: remove max device latency constraint: dev %s\n",
dev_name(dev));
else
pr_debug("OMAP PM: add max device latency constraint: dev %s, t = %ld usec\n",
dev_name(dev), t);
/*
* For current Linux, this needs to map the device to a
* powerdomain, then go through the list of current max lat
* constraints on that powerdomain and find the smallest. If
* the latency constraint has changed, the code should
* recompute the state to enter for the next powerdomain
* state. Conceivably, this code should also determine
* whether to actually disable the device clocks or not,
* depending on how long it takes to re-enable the clocks.
*
* TI CDP code can call constraint_set here.
*/
return 0;
}
int omap_pm_set_max_sdma_lat(struct device *dev, long t)
{
if (!dev || t < -1) {
WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
return -EINVAL;
}
if (t == -1)
pr_debug("OMAP PM: remove max DMA latency constraint: dev %s\n",
dev_name(dev));
else
pr_debug("OMAP PM: add max DMA latency constraint: dev %s, t = %ld usec\n",
dev_name(dev), t);
/*
* For current Linux PM QOS params, this code should scan the
* list of maximum CPU and DMA latencies and select the
* smallest, then set cpu_dma_latency pm_qos_param
* accordingly.
*
* For future Linux PM QOS params, with separate CPU and DMA
* latency params, this code should just set the dma_latency param.
*
* TI CDP code can call constraint_set here.
*/
return 0;
}
int omap_pm_set_min_clk_rate(struct device *dev, struct clk *c, long r)
{
if (!dev || !c || r < 0) {
WARN(1, "OMAP PM: %s: invalid parameter(s)", __func__);
return -EINVAL;
}
if (r == 0)
pr_debug("OMAP PM: remove min clk rate constraint: dev %s\n",
dev_name(dev));
else
pr_debug("OMAP PM: add min clk rate constraint: dev %s, rate = %ld Hz\n",
dev_name(dev), r);
/*
* Code in a real implementation should keep track of these
* constraints on the clock, and determine the highest minimum
* clock rate. It should iterate over each OPP and determine
* whether the OPP will result in a clock rate that would
* satisfy this constraint (and any other PM constraint in effect
* at that time). Once it finds the lowest-voltage OPP that
* meets those conditions, it should switch to it, or return
* an error if the code is not capable of doing so.
*/
return 0;
}
/*
* DSP Bridge-specific constraints
*/
const struct omap_opp *omap_pm_dsp_get_opp_table(void)
{
pr_debug("OMAP PM: DSP request for OPP table\n");
/*
* Return DSP frequency table here: The final item in the
* array should have .rate = .opp_id = 0.
*/
return NULL;
}
void omap_pm_dsp_set_min_opp(u8 opp_id)
{
if (opp_id == 0) {
WARN_ON(1);
return;
}
pr_debug("OMAP PM: DSP requests minimum VDD1 OPP to be %d\n", opp_id);
/*
*
* For l-o dev tree, our VDD1 clk is keyed on OPP ID, so we
* can just test to see which is higher, the CPU's desired OPP
* ID or the DSP's desired OPP ID, and use whichever is
* highest.
*
* In CDP12.14+, the VDD1 OPP custom clock that controls the DSP
* rate is keyed on MPU speed, not the OPP ID. So we need to
* map the OPP ID to the MPU speed for use with clk_set_rate()
* if it is higher than the current OPP clock rate.
*
*/
}
u8 omap_pm_dsp_get_opp(void)
{
pr_debug("OMAP PM: DSP requests current DSP OPP ID\n");
/*
* For l-o dev tree, call clk_get_rate() on VDD1 OPP clock
*
* CDP12.14+:
* Call clk_get_rate() on the OPP custom clock, map that to an
* OPP ID using the tables defined in board-*.c/chip-*.c files.
*/
return 0;
}
/*
* CPUFreq-originated constraint
*
* In the future, this should be handled by custom OPP clocktype
* functions.
*/
struct cpufreq_frequency_table **omap_pm_cpu_get_freq_table(void)
{
pr_debug("OMAP PM: CPUFreq request for frequency table\n");
/*
* Return CPUFreq frequency table here: loop over
* all VDD1 clkrates, pull out the mpu_ck frequencies, build
* table
*/
return NULL;
}
void omap_pm_cpu_set_freq(unsigned long f)
{
if (f == 0) {
WARN_ON(1);
return;
}
pr_debug("OMAP PM: CPUFreq requests CPU frequency to be set to %lu\n",
f);
/*
* For l-o dev tree, determine whether MPU freq or DSP OPP id
* freq is higher. Find the OPP ID corresponding to the
* higher frequency. Call clk_round_rate() and clk_set_rate()
* on the OPP custom clock.
*
* CDP should just be able to set the VDD1 OPP clock rate here.
*/
}
unsigned long omap_pm_cpu_get_freq(void)
{
pr_debug("OMAP PM: CPUFreq requests current CPU frequency\n");
/*
* Call clk_get_rate() on the mpu_ck.
*/
return 0;
}
/**
* omap_pm_enable_off_mode - notify OMAP PM that off-mode is enabled
*
* Intended for use only by OMAP PM core code to notify this layer
* that off mode has been enabled.
*/
void omap_pm_enable_off_mode(void)
{
off_mode_enabled = true;
}
/**
* omap_pm_disable_off_mode - notify OMAP PM that off-mode is disabled
*
* Intended for use only by OMAP PM core code to notify this layer
* that off mode has been disabled.
*/
void omap_pm_disable_off_mode(void)
{
off_mode_enabled = false;
}
/*
* Device context loss tracking
*/
#ifdef CONFIG_ARCH_OMAP2PLUS
int omap_pm_get_dev_context_loss_count(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
int count;
if (WARN_ON(!dev))
return -ENODEV;
if (dev->pm_domain == &omap_device_pm_domain) {
count = omap_device_get_context_loss_count(pdev);
} else {
WARN_ONCE(off_mode_enabled, "omap_pm: using dummy context loss counter; device %s should be converted to omap_device",
dev_name(dev));
count = dummy_context_loss_counter;
if (off_mode_enabled) {
count++;
/*
* Context loss count has to be a non-negative value.
* Clear the sign bit to get a value range from 0 to
* INT_MAX.
*/
count &= INT_MAX;
dummy_context_loss_counter = count;
}
}
pr_debug("OMAP PM: context loss count for dev %s = %d\n",
dev_name(dev), count);
return count;
}
#else
int omap_pm_get_dev_context_loss_count(struct device *dev)
{
return dummy_context_loss_counter;
}
#endif
/* Should be called before clk framework init */
int __init omap_pm_if_early_init(void)
{
return 0;
}
/* Must be called after clock framework is initialized */
int __init omap_pm_if_init(void)
{
return 0;
}
void omap_pm_if_exit(void)
{
/* Deallocate CPUFreq frequency table here */
}