From c0407a96d04794be586eab4a412320079446cf93 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 3 Sep 2009 20:14:01 +0300 Subject: OMAP2/3 PM: create the OMAP PM interface and add a default OMAP PM no-op layer MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The interface provides device drivers, CPUFreq, and DSPBridge with a means of controlling OMAP power management parameters that are not yet supported by the Linux PM PMQoS interface. Copious documentation is in the patch in Documentation/arm/OMAP/omap_pm and the interface header file, arch/arm/plat-omap/include/mach/omap-pm.h. Thanks to Rajendra Nayak for adding CORE (VDD2) OPP support and moving the OPP table initialization earlier in the event that the clock code needs them. Thanks to Tero Kristo for fixing the parameter check in omap_pm_set_min_bus_tput(). Jouni signed off on Tero's patch. Signed-off-by: Paul Walmsley Signed-off-by: Kevin Hilman Signed-off-by: Rajendra Nayak Signed-off-by: Tero Kristo Signed-off-by: Jouni Högander Cc: Tony Lindgren Cc: Igor Stoppa Cc: Richard Woodruff Cc: Anand Sawant Cc: Sakari Poussa Cc: Veeramanikandan Raju Cc: Karthik Dasu --- arch/arm/plat-omap/include/mach/omap-pm.h | 301 ++++++++++++++++++++++++++++++ 1 file changed, 301 insertions(+) create mode 100644 arch/arm/plat-omap/include/mach/omap-pm.h (limited to 'arch/arm/plat-omap/include/mach') diff --git a/arch/arm/plat-omap/include/mach/omap-pm.h b/arch/arm/plat-omap/include/mach/omap-pm.h new file mode 100644 index 00000000000..3ee41d71149 --- /dev/null +++ b/arch/arm/plat-omap/include/mach/omap-pm.h @@ -0,0 +1,301 @@ +/* + * omap-pm.h - OMAP power management interface + * + * Copyright (C) 2008-2009 Texas Instruments, Inc. + * Copyright (C) 2008-2009 Nokia Corporation + * Paul Walmsley + * + * Interface developed by (in alphabetical order): Karthik Dasu, Jouni + * Högander, Tony Lindgren, Rajendra Nayak, Sakari Poussa, + * Veeramanikandan Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, + * Richard Woodruff + */ + +#ifndef ASM_ARM_ARCH_OMAP_OMAP_PM_H +#define ASM_ARM_ARCH_OMAP_OMAP_PM_H + +#include +#include + +#include "powerdomain.h" + +/** + * struct omap_opp - clock frequency-to-OPP ID table for DSP, MPU + * @rate: target clock rate + * @opp_id: OPP ID + * @min_vdd: minimum VDD1 voltage (in millivolts) for this OPP + * + * Operating performance point data. Can vary by OMAP chip and board. + */ +struct omap_opp { + unsigned long rate; + u8 opp_id; + u16 min_vdd; +}; + +extern struct omap_opp *mpu_opps; +extern struct omap_opp *dsp_opps; +extern struct omap_opp *l3_opps; + +/* + * agent_id values for use with omap_pm_set_min_bus_tput(): + * + * OCP_INITIATOR_AGENT is only valid for devices that can act as + * initiators -- it represents the device's L3 interconnect + * connection. OCP_TARGET_AGENT represents the device's L4 + * interconnect connection. + */ +#define OCP_TARGET_AGENT 1 +#define OCP_INITIATOR_AGENT 2 + +/** + * omap_pm_if_early_init - OMAP PM init code called before clock fw init + * @mpu_opp_table: array ptr to struct omap_opp for MPU + * @dsp_opp_table: array ptr to struct omap_opp for DSP + * @l3_opp_table : array ptr to struct omap_opp for CORE + * + * Initialize anything that must be configured before the clock + * framework starts. The "_if_" is to avoid name collisions with the + * PM idle-loop code. + */ +int __init omap_pm_if_early_init(struct omap_opp *mpu_opp_table, + struct omap_opp *dsp_opp_table, + struct omap_opp *l3_opp_table); + +/** + * omap_pm_if_init - OMAP PM init code called after clock fw init + * + * The main initialization code. OPP tables are passed in here. The + * "_if_" is to avoid name collisions with the PM idle-loop code. + */ +int __init omap_pm_if_init(void); + +/** + * omap_pm_if_exit - OMAP PM exit code + * + * Exit code; currently unused. The "_if_" is to avoid name + * collisions with the PM idle-loop code. + */ +void omap_pm_if_exit(void); + +/* + * Device-driver-originated constraints (via board-*.c files, platform_data) + */ + + +/** + * omap_pm_set_max_mpu_wakeup_lat - set the maximum MPU wakeup latency + * @dev: struct device * requesting the constraint + * @t: maximum MPU wakeup latency in microseconds + * + * Request that the maximum interrupt latency for the MPU to be no + * greater than 't' microseconds. "Interrupt latency" in this case is + * defined as the elapsed time from the occurrence of a hardware or + * timer interrupt to the time when the device driver's interrupt + * service routine has been entered by the MPU. + * + * It is intended that underlying PM code will use this information to + * determine what power state to put the MPU powerdomain into, and + * possibly the CORE powerdomain as well, since interrupt handling + * code currently runs from SDRAM. Advanced PM or board*.c code may + * also configure interrupt controller priorities, OCP bus priorities, + * CPU speed(s), etc. + * + * This function will not affect device wakeup latency, e.g., time + * elapsed from when a device driver enables a hardware device with + * clk_enable(), to when the device is ready for register access or + * other use. To control this device wakeup latency, use + * set_max_dev_wakeup_lat() + * + * Multiple calls to set_max_mpu_wakeup_lat() will replace the + * previous t value. To remove the latency target for the MPU, call + * with t = -1. + * + * No return value. + */ +void omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t); + + +/** + * omap_pm_set_min_bus_tput - set minimum bus throughput needed by device + * @dev: struct device * requesting the constraint + * @tbus_id: interconnect to operate on (OCP_{INITIATOR,TARGET}_AGENT) + * @r: minimum throughput (in KiB/s) + * + * Request that the minimum data throughput on the OCP interconnect + * attached to device 'dev' interconnect agent 'tbus_id' be no less + * than 'r' KiB/s. + * + * It is expected that the OMAP PM or bus code will use this + * information to set the interconnect clock to run at the lowest + * possible speed that satisfies all current system users. The PM or + * bus code will adjust the estimate based on its model of the bus, so + * device driver authors should attempt to specify an accurate + * quantity for their device use case, and let the PM or bus code + * overestimate the numbers as necessary to handle request/response + * latency, other competing users on the system, etc. On OMAP2/3, if + * a driver requests a minimum L4 interconnect speed constraint, the + * code will also need to add an minimum L3 interconnect speed + * constraint, + * + * Multiple calls to set_min_bus_tput() will replace the previous rate + * value for this device. To remove the interconnect throughput + * restriction for this device, call with r = 0. + * + * No return value. + */ +void omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r); + + +/** + * omap_pm_set_max_dev_wakeup_lat - set the maximum device enable latency + * @dev: struct device * + * @t: maximum device wakeup latency in microseconds + * + * Request that the maximum amount of time necessary for a device to + * become accessible after its clocks are enabled should be no greater + * than 't' microseconds. Specifically, this represents the time from + * when a device driver enables device clocks with clk_enable(), to + * when the register reads and writes on the device will succeed. + * This function should be called before clk_disable() is called, + * since the power state transition decision may be made during + * clk_disable(). + * + * It is intended that underlying PM code will use this information to + * determine what power state to put the powerdomain enclosing this + * device into. + * + * Multiple calls to set_max_dev_wakeup_lat() will replace the + * previous wakeup latency values for this device. To remove the wakeup + * latency restriction for this device, call with t = -1. + * + * No return value. + */ +void omap_pm_set_max_dev_wakeup_lat(struct device *dev, long t); + + +/** + * omap_pm_set_max_sdma_lat - set the maximum system DMA transfer start latency + * @dev: struct device * + * @t: maximum DMA transfer start latency in microseconds + * + * Request that the maximum system DMA transfer start latency for this + * device 'dev' should be no greater than 't' microseconds. "DMA + * transfer start latency" here is defined as the elapsed time from + * when a device (e.g., McBSP) requests that a system DMA transfer + * start or continue, to the time at which data starts to flow into + * that device from the system DMA controller. + * + * It is intended that underlying PM code will use this information to + * determine what power state to put the CORE powerdomain into. + * + * Since system DMA transfers may not involve the MPU, this function + * will not affect MPU wakeup latency. Use set_max_cpu_lat() to do + * so. Similarly, this function will not affect device wakeup latency + * -- use set_max_dev_wakeup_lat() to affect that. + * + * Multiple calls to set_max_sdma_lat() will replace the previous t + * value for this device. To remove the maximum DMA latency for this + * device, call with t = -1. + * + * No return value. + */ +void omap_pm_set_max_sdma_lat(struct device *dev, long t); + + +/* + * DSP Bridge-specific constraints + */ + +/** + * omap_pm_dsp_get_opp_table - get OPP->DSP clock frequency table + * + * Intended for use by DSPBridge. Returns an array of OPP->DSP clock + * frequency entries. The final item in the array should have .rate = + * .opp_id = 0. + */ +const struct omap_opp *omap_pm_dsp_get_opp_table(void); + +/** + * omap_pm_dsp_set_min_opp - receive desired OPP target ID from DSP Bridge + * @opp_id: target DSP OPP ID + * + * Set a minimum OPP ID for the DSP. This is intended to be called + * only from the DSP Bridge MPU-side driver. Unfortunately, the only + * information that code receives from the DSP/BIOS load estimator is the + * target OPP ID; hence, this interface. No return value. + */ +void omap_pm_dsp_set_min_opp(u8 opp_id); + +/** + * omap_pm_dsp_get_opp - report the current DSP OPP ID + * + * Report the current OPP for the DSP. Since on OMAP3, the DSP and + * MPU share a single voltage domain, the OPP ID returned back may + * represent a higher DSP speed than the OPP requested via + * omap_pm_dsp_set_min_opp(). + * + * Returns the current VDD1 OPP ID, or 0 upon error. + */ +u8 omap_pm_dsp_get_opp(void); + + +/* + * CPUFreq-originated constraint + * + * In the future, this should be handled by custom OPP clocktype + * functions. + */ + +/** + * omap_pm_cpu_get_freq_table - return a cpufreq_frequency_table array ptr + * + * Provide a frequency table usable by CPUFreq for the current chip/board. + * Returns a pointer to a struct cpufreq_frequency_table array or NULL + * upon error. + */ +struct cpufreq_frequency_table **omap_pm_cpu_get_freq_table(void); + +/** + * omap_pm_cpu_set_freq - set the current minimum MPU frequency + * @f: MPU frequency in Hz + * + * Set the current minimum CPU frequency. The actual CPU frequency + * used could end up higher if the DSP requested a higher OPP. + * Intended to be called by plat-omap/cpu_omap.c:omap_target(). No + * return value. + */ +void omap_pm_cpu_set_freq(unsigned long f); + +/** + * omap_pm_cpu_get_freq - report the current CPU frequency + * + * Returns the current MPU frequency, or 0 upon error. + */ +unsigned long omap_pm_cpu_get_freq(void); + + +/* + * Device context loss tracking + */ + +/** + * omap_pm_get_dev_context_loss_count - return count of times dev has lost ctx + * @dev: struct device * + * + * This function returns the number of times that the device @dev has + * lost its internal context. This generally occurs on a powerdomain + * transition to OFF. Drivers use this as an optimization to avoid restoring + * context if the device hasn't lost it. To use, drivers should initially + * call this in their context save functions and store the result. Early in + * the driver's context restore function, the driver should call this function + * again, and compare the result to the stored counter. If they differ, the + * driver must restore device context. If the number of context losses + * exceeds the maximum positive integer, the function will wrap to 0 and + * continue counting. Returns the number of context losses for this device, + * or -EINVAL upon error. + */ +int omap_pm_get_dev_context_loss_count(struct device *dev); + + +#endif -- cgit v1.2.3