/* * 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> #include "omap_device.h" #include "omap-pm.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 */ }