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author | Paul Walmsley <paul@pwsan.com> | 2009-09-03 20:14:01 +0300 |
---|---|---|
committer | paul <paul@twilight.(none)> | 2009-09-03 20:14:01 +0300 |
commit | c0407a96d04794be586eab4a412320079446cf93 (patch) | |
tree | 5993b7f57105ecac8a788e908539dfeaad654efe /arch/arm | |
parent | 08e3d5f28d4d696dc559898676019cbd36501025 (diff) | |
download | linux-3.10-c0407a96d04794be586eab4a412320079446cf93.tar.gz linux-3.10-c0407a96d04794be586eab4a412320079446cf93.tar.bz2 linux-3.10-c0407a96d04794be586eab4a412320079446cf93.zip |
OMAP2/3 PM: create the OMAP PM interface and add a default OMAP PM no-op layer
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 <rnayak@ti.com> 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
<tero.kristo@nokia.com> for fixing the parameter check in
omap_pm_set_min_bus_tput(). Jouni signed off on Tero's patch.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Jouni Högander <jouni.hogander@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Igor Stoppa <igor.stoppa@nokia.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: Anand Sawant <sawant@ti.com>
Cc: Sakari Poussa <sakari.poussa@nokia.com>
Cc: Veeramanikandan Raju <veera@ti.com>
Cc: Karthik Dasu <karthik-dp@ti.com>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/mach-omap2/io.c | 4 | ||||
-rw-r--r-- | arch/arm/plat-omap/Kconfig | 13 | ||||
-rw-r--r-- | arch/arm/plat-omap/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/plat-omap/include/mach/omap-pm.h | 301 | ||||
-rw-r--r-- | arch/arm/plat-omap/omap-pm-noop.c | 296 |
5 files changed, 615 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c index e9b9bcb19b4..4bfe873e1b8 100644 --- a/arch/arm/mach-omap2/io.c +++ b/arch/arm/mach-omap2/io.c @@ -36,6 +36,7 @@ #ifndef CONFIG_ARCH_OMAP4 /* FIXME: Remove this once clkdev is ready */ #include "clock.h" +#include <mach/omap-pm.h> #include <mach/powerdomain.h> #include "powerdomains.h" @@ -281,9 +282,12 @@ void __init omap2_init_common_hw(struct omap_sdrc_params *sdrc_cs0, { omap2_mux_init(); #ifndef CONFIG_ARCH_OMAP4 /* FIXME: Remove this once the clkdev is ready */ + /* The OPP tables have to be registered before a clk init */ + omap_pm_if_early_init(mpu_opps, dsp_opps, l3_opps); pwrdm_init(powerdomains_omap); clkdm_init(clockdomains_omap, clkdm_pwrdm_autodeps); omap2_clk_init(); + omap_pm_if_init(); omap2_sdrc_init(sdrc_cs0, sdrc_cs1); _omap2_init_reprogram_sdrc(); #endif diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig index ab9f9efc9b6..64b3f52bd9b 100644 --- a/arch/arm/plat-omap/Kconfig +++ b/arch/arm/plat-omap/Kconfig @@ -187,6 +187,19 @@ config OMAP_SERIAL_WAKE to data on the serial RX line. This allows you to wake the system from serial console. +choice + prompt "OMAP PM layer selection" + depends on ARCH_OMAP + default OMAP_PM_NOOP + +config OMAP_PM_NONE + bool "No PM layer" + +config OMAP_PM_NOOP + bool "No-op/debug PM layer" + +endchoice + endmenu endif diff --git a/arch/arm/plat-omap/Makefile b/arch/arm/plat-omap/Makefile index 769a4c20036..5e10d0a2eb8 100644 --- a/arch/arm/plat-omap/Makefile +++ b/arch/arm/plat-omap/Makefile @@ -26,3 +26,4 @@ obj-y += $(i2c-omap-m) $(i2c-omap-y) # OMAP mailbox framework obj-$(CONFIG_OMAP_MBOX_FWK) += mailbox.o +obj-$(CONFIG_OMAP_PM_NOOP) += omap-pm-noop.o
\ No newline at end of file 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 <linux/device.h> +#include <linux/cpufreq.h> + +#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 diff --git a/arch/arm/plat-omap/omap-pm-noop.c b/arch/arm/plat-omap/omap-pm-noop.c new file mode 100644 index 00000000000..e98f0a2a6c2 --- /dev/null +++ b/arch/arm/plat-omap/omap-pm-noop.c @@ -0,0 +1,296 @@ +/* + * 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> + +/* Interface documentation is in mach/omap-pm.h */ +#include <mach/omap-pm.h> + +#include <mach/powerdomain.h> + +struct omap_opp *dsp_opps; +struct omap_opp *mpu_opps; +struct omap_opp *l3_opps; + +/* + * Device-driver-originated constraints (via board-*.c files) + */ + +void omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t) +{ + if (!dev || t < -1) { + WARN_ON(1); + return; + }; + + 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. + */ +} + +void 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_ON(1); + return; + }; + + 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. + */ +} + +void omap_pm_set_max_dev_wakeup_lat(struct device *dev, long t) +{ + if (!dev || t < -1) { + WARN_ON(1); + return; + }; + + 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. + */ +} + +void omap_pm_set_max_sdma_lat(struct device *dev, long t) +{ + if (!dev || t < -1) { + WARN_ON(1); + return; + }; + + 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. + */ + +} + + +/* + * 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; +} + +/* + * Device context loss tracking + */ + +int omap_pm_get_dev_context_loss_count(struct device *dev) +{ + if (!dev) { + WARN_ON(1); + return -EINVAL; + }; + + pr_debug("OMAP PM: returning context loss count for dev %s\n", + dev_name(dev)); + + /* + * Map the device to the powerdomain. Return the powerdomain + * off counter. + */ + + return 0; +} + + +/* Should be called before clk framework init */ +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) +{ + mpu_opps = mpu_opp_table; + dsp_opps = dsp_opp_table; + l3_opps = l3_opp_table; + 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 */ +} + |