Hi,
On Tue, Mar 1, 2011 at 3:47 PM, Menon, Nishanth <nm@xxxxxx> wrote:
> On Tue, Mar 1, 2011 at 15:23, Gulati, Shweta <shweta.gulati@xxxxxx> wrote:
>>
>> Hi,
>>
>> On Sat, Feb 19, 2011 at 5:31 PM, Nishanth Menon <nm@xxxxxx> wrote:
>> > Traditional SmartReflex AVS(Automatic Voltage Scaling) classes are:
>> > * Class 0 - Product test calibration
>> > Silicon is calibration at production floor and fused with voltages
>> > for each OPP
>> > * Class 1 - Boot time calibration
>> > Silicon is calibrated once at boot time and voltages are stored for
>> > the lifetime of operation.
>> > * Class 2 - continuous s/w calibration
>> > SR module notifies s/w for any change in the system which is desired
>> > and the s/w makes runtime decisions in terms of setting the voltage,
>> > this mechanism could be used in the system which does not have PMIC
>> > capable of SR without using the voltage controller and voltage
>> > processor blocks.
>> > * Class 3 - continuous h/w calibration
>> > SR module is switch on after reaching a voltage level and SR
>> > continuously monitors the system and makes runtime adjustments without
>> > s/w involvement.
>> >
>> > OMAP3430 has used SmartReflex AVS and with a a PMIC which understands the SR
>> > protocol, Class 3 has been used. With OMAP3630 onwards, a new SmartReflex AVS
>> > class of operation Class 1.5 was introduced.
>> > * Class 1.5 - periodic s/w calibration
>> > This uses the h/w calibration loop and at the end of calibration
>> > stores the voltages to be used run time, periodic recalibration is
>> > performed as well.
>> >
>> > The operational mode is describes as the following:
>> > * SmartReflex AVS h/w calibration loop is essential to identify the optimal
>> > voltage for a given OPP.
>> > * Once this optimal voltage is detected, SmartReflex AVS loop is disabled in
>> > class 1.5 mode of operation.
>> > * Until there is a need for a recalibration, any further transition to an OPP
>> > voltage which is calibrated can use the calibrated voltage and does not
>> > require enabling the SR AVS h/w loop.
>> > * On a periodic basis (recommendation being once approximately every 24 hours),
>> > software is expected to perform a recalibration to find a new optimal
>> > voltage which is compensated for device aging.
>> > - For performing this recalibration, the start voltage does not need to
>> > be the nominal voltage anymore. instead, the system can start with a
>> > voltage which is 50mV higher than the previously calibrated voltage to
>> > identify the new optimal voltage as the aging factor within a period of
>> > 1 day is not going to be anywhere close to 50mV.
>> > - This "new starting point" for recalibration is called a dynamic
>> > nominal voltage for that voltage point.
>> > In short, with the introduction of SmartReflex class 1.5, there are three new
>> > voltages possible in a system's dvfs transition:
>> > * Nominal Voltage - The maximum voltage needed for a worst possible device
>> > in the worst possible conditions. This is the voltage we choose as
>> > the starting point for the h/w loop to optimize for the first time
>> > calibration on system bootup.
>> > * Dynamic Nominal Voltage - Worst case voltage for a specific device in
>> > considering the system aging on the worst process device.
>> > * Calibrated Voltage - Best voltage for the current device at a given point
>> > of time.
>> >
>> > In terms of the implementation, doing calibration involves waiting for the
>> > smartreflex h/w loop to settle down, and doing this as part of the dvfs flow
>> > itself is to increase the latency of dvfs transition when there is a need to
>> > calibrate that opp. instead, the calibration is performed "out of path" using
>> > a workqueue statemachine. The workqueue waits for the system stabilization,
>> > then enables VP interrupts to monitor for system instability interms of voltage
>> > oscillations that are reported back to the system as interrupts, in case of
>> > prolonged system oscillations, nominal voltage is chosen as a safe voltage and
>> > this event is logged in the system log for developer debug and fixing.
>> >
>> > For the recalibration, a common workqueue for all domains is started at the
>> > start of the class initialization and it resets the calibrated voltages
>> > on a periodic basis. For distros that may choose not to do the recommended
>> > periodic recalibration, instead choose to perform boot time calibration,
>> > kconfig configuration option is provided to do so.
>> >
>> > TODO:
>> > a) Cpuidle and suspend paths are not integrated with SmartReflex driver at
>> > this point.
>> > b) Since the SR registers are accessed and controlled in parallel to DVFS
>> > some sort of mechanism is necessary to be introduced along with OMAP
>> > dvfs layer to ensure mutual exclusivity
>> > c) Additional debug interfaces for vmin analysis for platform characterization
>> > and addition of system margin needs to be introduced from smartreflex
>> > perspective.
>> >
>> > This implementation also includes the following contributors:
>> > Tony Lindgren for suggestion on using interrupt based mechanism instead of
>> > polling to detect voltage oscillations.
>> > Peter 'p2' De Schrijver for debating alternatives on recalibration mechanisms
>> > Paul Walmsey, Eduardo Valentin, Ambresh K, Igor Dmitriev and quiet a few others
>> > for patient review, testing and reporting of issues of a previous incarnation
>> > of this implemenation. Last, but not the least, the TI H/w team in introducing
>> > this new SR AVS class and patiently debating it's various facets.
>> >
>> > Cc: Ambresh K <ambresh@xxxxxx>
>> > Cc: Eduardo Valentin <eduardo.valentin@xxxxxxxxx>
>> > Cc: Igor Dmitriev <ext-dmitriev.igor@xxxxxxxxx>
>> > Cc: Paul <paul@xxxxxxxxx>
>> > Cc: Peter 'p2' De Schrijver <Peter.De-Schrijver@xxxxxxxxx>
>> > Cc: Tony Lindgren <tony@xxxxxxxxxxx>
>> >
>> > Signed-off-by: Nishanth Menon <nm@xxxxxx>
>> > ---
>> > arch/arm/mach-omap2/Makefile | 1 +
>> > arch/arm/mach-omap2/smartreflex-class1p5.c | 556 +++++++++++++++++++++++++
>> > arch/arm/mach-omap2/smartreflex-class3.c | 4 +-
>> > arch/arm/mach-omap2/smartreflex.c | 34 ++-
>> > arch/arm/mach-omap2/voltage.c | 69 +++
>> > arch/arm/plat-omap/Kconfig | 17 +
>> > arch/arm/plat-omap/include/plat/smartreflex.h | 13 +-
>> > arch/arm/plat-omap/include/plat/voltage.h | 23 +-
>> > 8 files changed, 709 insertions(+), 8 deletions(-)
>> > create mode 100644 arch/arm/mach-omap2/smartreflex-class1p5.c
>> >
>> > diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
>> > index 1c0c2b0..1a82e6d 100644
>> > --- a/arch/arm/mach-omap2/Makefile
>> > +++ b/arch/arm/mach-omap2/Makefile
>> > @@ -66,6 +66,7 @@ obj-$(CONFIG_ARCH_OMAP4) += pm44xx.o voltage.o pm_bus.o
>> > obj-$(CONFIG_PM_DEBUG) += pm-debug.o
>> > obj-$(CONFIG_OMAP_SMARTREFLEX) += sr_device.o smartreflex.o
>> > obj-$(CONFIG_OMAP_SMARTREFLEX_CLASS3) += smartreflex-class3.o
>> > +obj-$(CONFIG_OMAP_SMARTREFLEX_CLASS1P5) += smartreflex-class1p5.o
>> >
>> > AFLAGS_sleep24xx.o :=-Wa,-march=armv6
>> > AFLAGS_sleep34xx.o :=-Wa,-march=armv7-a
>> > diff --git a/arch/arm/mach-omap2/smartreflex-class1p5.c b/arch/arm/mach-omap2/smartreflex-class1p5.c
>> > new file mode 100644
>> > index 0000000..832f10b
>> > --- /dev/null
>> > +++ b/arch/arm/mach-omap2/smartreflex-class1p5.c
>> > @@ -0,0 +1,556 @@
>> > +/*
>> > + * Smart reflex Class 1.5 specific implementations
>> > + *
>> > + * Copyright (C) 2010-2011 Texas Instruments, Inc.
>> > + * Nishanth Menon <nm@xxxxxx>
>> > + *
>> > + * Smart reflex class 1.5 is also called periodic SW Calibration
>> > + * Some of the highlights are as follows:
>> > + * – Host CPU triggers OPP calibration when transitioning to non calibrated
>> > + * OPP
>> > + * – SR-AVS + VP modules are used to perform calibration
>> > + * – Once completed, the SmartReflex-AVS module can be disabled
>> > + * – Enables savings based on process, supply DC accuracy and aging
>> > + *
>> > + * This program is free software; you can redistribute it and/or modify
>> > + * it under the terms of the GNU General Public License version 2 as
>> > + * published by the Free Software Foundation.
>> > + */
>> > +#include <linux/kernel.h>
>> > +#include <linux/delay.h>
>> > +#include <linux/err.h>
>> > +#include <linux/io.h>
>> > +#include <linux/fs.h>
>> > +#include <linux/string.h>
>> > +#include <linux/uaccess.h>
>> > +#include <linux/kobject.h>
>> > +#include <linux/workqueue.h>
>> > +#include <linux/opp.h>
>> > +
>> > +#include <plat/smartreflex.h>
>> > +#include <plat/voltage.h>
>> > +
>> > +#define MAX_VDDS 3
>> > +#define SR1P5_SAMPLING_DELAY_MS 1
>> > +#define SR1P5_STABLE_SAMPLES 5
>> > +#define SR1P5_MAX_TRIGGERS 5
>> > +
>> > +/*
>> > + * we expect events in 10uS, if we dont get 2wice times as much,
>> > + * we could kind of ignore this as a missed event.
>> > + */
>> > +#define MAX_CHECK_VPTRANS_US 20
>> > +
>> > +/**
>> > + * struct sr_class1p5_work_data - data meant to be used by calibration work
>> > + * @work: calibration work
>> > + * @voltdm: voltage domain for which we are triggering
>> > + * @vdata: voltage data we are calibrating
>> > + * @num_calib_triggers: number of triggers from calibration loop
>> > + * @num_osc_samples: number of samples collected by isr
>> > + * @work_active: have we scheduled a work item?
>> > + */
>> > +struct sr_class1p5_work_data {
>> > + struct delayed_work work;
>> > + struct voltagedomain *voltdm;
>> > + struct omap_volt_data *vdata;
>> > + u8 num_calib_triggers;
>> > + u8 num_osc_samples;
>> > + bool work_active;
>> > +};
>> > +
>> > +#if CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY
>> > +/* recal_work: recalibration calibration work */
>> > +static struct delayed_work recal_work;
>> > +#endif
>> > +
>> > +/**
>> > + * struct sr_class1p5_data - private data for class 1p5
>> > + * @work_data: work item data per voltage domain
>> > + */
>> > +struct sr_class1p5_data {
>> > + struct sr_class1p5_work_data work_data[MAX_VDDS];
>> > +};
>> > +
>> > +static void sr_class1p5_reset_calib(struct voltagedomain *voltdm, bool reset,
>> > + bool recal);
>> > +
>> > +/* our instance of class 1p5 private data */
>> > +static struct sr_class1p5_data class_1p5_data;
>> > +
>> > +static struct sr_class1p5_work_data *get_sr1p5_work(struct voltagedomain
>> > + *voltdm)
>> > +{
>> > + int idx;
>> > + for (idx = 0; idx < MAX_VDDS; idx++) {
>> > + if (class_1p5_data.work_data[idx].voltdm && !strcmp
>> > + (class_1p5_data.work_data[idx].voltdm->name, voltdm->name))
>> > + return &class_1p5_data.work_data[idx];
>> > + }
>> > + return ERR_PTR(-ENODATA);
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_notify() - isr notifier for status events
>> > + * @voltdm: voltage domain for which we were triggered
>> > + * @status: notifier event to use
>> > + *
>> > + * This basically collects data for the work to use.
>> > + */
>> > +static int sr_class1p5_notify(struct voltagedomain *voltdm, u32 status)
>> > +{
>> > + struct sr_class1p5_work_data *work_data;
>> > + int idx = 0;
>> > + work_data = get_sr1p5_work(voltdm);
>> > +
>> > + if (unlikely(!work_data)) {
>> > + pr_err("%s:%s no work data!!\n", __func__, voltdm->name);
>> > + return -EINVAL;
>> > + }
>> > +
>> > + /* Wait for transdone so that we know the voltage to read */
>> > + do {
>> > + if (omap_vp_is_transdone(voltdm))
>> > + break;
>> > + idx++;
>> > + /* get some constant delay */
>> > + udelay(1);
>> > + } while (idx < MAX_CHECK_VPTRANS_US);
>> > +
>> > + /*
>> > + * If we timeout, we still read the data,
>> > + * if we are oscillating+irq latencies are too high, we could
>> > + * have scenarios where we miss transdone event. since
>> > + * we waited long enough, it is still safe to read the voltage
>> > + * as we would have waited long enough - still flag it..
>> > + */
>> > + if (idx >= MAX_CHECK_VPTRANS_US)
>> > + pr_warning("%s: timed out waiting for transdone!!\n", __func__);
>> > +
>> > + omap_vp_clear_transdone(voltdm);
>> > +
>> > + idx = (work_data->num_osc_samples) % SR1P5_STABLE_SAMPLES;
>> > + work_data->num_osc_samples++;
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +/**
>> > + * do_calibrate() - work which actually does the calibration
>> > + * @work: pointer to the work
>> > + *
>> > + * calibration routine uses the following logic:
>> > + * on the first trigger, we start the isr to collect sr voltages
>> > + * wait for stabilization delay (reschdule self instead of sleeping)
>> > + * after the delay, see if we collected any isr events
>> > + * if none, we have calibrated voltage.
>> > + * if there are any, we retry untill we giveup.
>> > + * on retry timeout, select a voltage to use as safe voltage.
>> > + */
>> > +static void do_calibrate(struct work_struct *work)
>> > +{
>> > + struct sr_class1p5_work_data *work_data =
>> > + container_of(work, struct sr_class1p5_work_data, work.work);
>> > + unsigned long u_volt_safe = 0, u_volt_current = 0;
>> > + struct omap_volt_data *volt_data;
>> > + struct voltagedomain *voltdm;
>> > +
>> > + if (unlikely(!work_data)) {
>> > + pr_err("%s: ooops.. null work_data?\n", __func__);
>> > + return;
>> > + }
>> > +
>> > + /*
>> > + * TODO:Handle the case where we might have just been scheduled AND
>> > + * 1.5 disable was called. check and HOLD dvfs
>> > + */
>> > +
>> > + voltdm = work_data->voltdm;
>> > + /*
>> > + * In the unlikely case that we did get through when unplanned,
>> > + * flag and return.
>> > + */
>> > + if (unlikely(!work_data->work_active)) {
>> > + pr_err("%s:%s unplanned work invocation!\n", __func__,
>> > + voltdm->name);
>> > + /* TODO release the dvfs */
>> > + return;
>> > + }
>> > +
>> > + work_data->num_calib_triggers++;
>> > + /* if we are triggered first time, we need to start isr to sample */
>> > + if (work_data->num_calib_triggers == 1)
>> > + goto start_sampling;
>> > +
>> > + /* Stop isr from interrupting our measurements :) */
>> > + sr_notifier_control(voltdm, false);
>> > +
>> > + volt_data = work_data->vdata;
>> > +
>> > + /* if there are no samples captured.. SR is silent, aka stability! */
>> > + if (!work_data->num_osc_samples) {
>> > + u_volt_safe = omap_vp_get_curr_volt(voltdm);
>> > + u_volt_current = u_volt_safe;
>> > + goto done_calib;
>> > + }
>> > + if (work_data->num_calib_triggers == SR1P5_MAX_TRIGGERS) {
>> > + pr_warning("%s: %s recalib timeout!\n", __func__,
>> > + work_data->voltdm->name);
>> > + goto oscillating_calib;
>> > + }
>> > +
>> > + /* we have potential oscillations/first sample */
>> > +start_sampling:
>> > + work_data->num_osc_samples = 0;
>> > + /* Clear pending events */
>> > + sr_notifier_control(voltdm, false);
>> > + /* Clear all transdones */
>> > + while (omap_vp_is_transdone(voltdm))
>> > + omap_vp_clear_transdone(voltdm);
>> > + /* trigger sampling */
>> > + sr_notifier_control(voltdm, true);
>> > + schedule_delayed_work(&work_data->work,
>> > + msecs_to_jiffies(SR1P5_SAMPLING_DELAY_MS *
>> > + SR1P5_STABLE_SAMPLES));
>> > + /* TODO: release dvfs */
>> > + return;
>> > +
>> > +oscillating_calib:
>> > + /* Use the nominal voltage as the safe voltage */
>> > + u_volt_safe = volt_data->volt_nominal;
>> > + /* pick up current voltage to switch if needed */
>> > + u_volt_current = omap_vp_get_curr_volt(voltdm);
>> > +
>> > + /* Fall through to close up common stuff */
>> > +done_calib:
>> > + omap_vp_disable(voltdm);
>> > + sr_disable(voltdm);
>> > +
>> > + volt_data->volt_calibrated = u_volt_safe;
>> > + /* Setup my dynamic voltage for the next calibration for this opp */
>> > + volt_data->volt_dynamic_nominal = omap_get_dyn_nominal(volt_data);
>> > +
>> > + /*
>> > + * if the voltage we decided as safe is not the current voltage,
>> > + * switch
>> > + */
>> > + if (volt_data->volt_calibrated != u_volt_current) {
>> > + pr_debug("%s:%s reconfiguring to voltage %d\n",
>> > + __func__, voltdm->name, volt_data->volt_calibrated);
>> > + omap_voltage_scale_vdd(voltdm, volt_data);
>> > + }
>> > +
>> > + /*
>> > + * TODO: Setup my wakeup voltage to allow immediate going to OFF and
>> > + * on - Pending twl and voltage layer cleanups.
>> > + * This is necessary, as this is not done as part of regular
>> > + * Dvfs flow.
>> > + * vc_setup_on_voltage(voltdm, volt_data->volt_calibrated);
>> > + */
>> > + work_data->work_active = false;
>> > + /* TODO: release dvfs */
>> > +}
>> > +
>> > +#if CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY
>> > +/**
>> > + * do_recalibrate() - work which actually does the calibration
>> > + * @work: pointer to the work
>> > + *
>> > + * on a periodic basis, we come and reset our calibration setup
>> > + * so that a recalibration of the OPPs take place. This takes
>> > + * care of aging factor in the system.
>> > + */
>> > +static void do_recalibrate(struct work_struct *work)
>> > +{
>> > + struct voltagedomain *voltdm;
>> > + int idx;
>> > + static struct sr_class1p5_work_data *work_data;
>> > +
>> > + for (idx = 0; idx < MAX_VDDS; idx++) {
>> > + work_data = &class_1p5_data.work_data[idx];
>> > + voltdm = work_data->voltdm;
>> > + if (voltdm) {
>> > + /* if sr is not enabled, we check later */
>> > + if (!is_sr_enabled(voltdm))
>> > + continue;
>> > + /* TODO: Pause the dvfs transitions */
>> > + /* if sr is not enabled, we check later */
>> > +
>> > + /* Reset and force a recalibration for current opp */
>> > + sr_class1p5_reset_calib(voltdm, true, true);
>> > +
>> > + /* TODO: unpause DVFS transitions */
>> > + }
>> > + }
>> > + /* We come back again after time the usual delay */
>> > + schedule_delayed_work(&recal_work,
>> > + msecs_to_jiffies(CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY));
>> > +}
>> > +#endif /* CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY */
>> > +
>> > +/**
>> > + * sr_class1p5_enable() - class 1.5 mode of enable
>> > + * @voltdm: voltage domain to enable SR for
>> > + * @volt_data: voltdata to the voltage transition taking place
>> > + *
>> > + * when this gets called, we use the h/w loop to setup our voltages
>> > + * to an calibrated voltage, detect any oscillations, recover from the same
>> > + * and finally store the optimized voltage as the calibrated voltage in the
>> > + * system
>> > + */
>> > +static int sr_class1p5_enable(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *volt_data)
>> > +{
>> > + int r;
>> > + struct sr_class1p5_work_data *work_data;
>> > + /* if already calibrated, nothing to do here.. */
>> > + if (volt_data->volt_calibrated)
>> > + return 0;
>> > +
>> > + work_data = get_sr1p5_work(voltdm);
>> > + if (unlikely(!work_data)) {
>> > + pr_err("%s: aieeee.. bad work data??\n", __func__);
>> > + return -EINVAL;
>> > + }
>> > +
>> > + if (work_data->work_active)
>> > + return 0;
>> > +
>> > + omap_vp_enable(voltdm);
>> > + r = sr_enable(voltdm, volt_data);
>> > + if (r) {
>> > + pr_err("%s: sr[%s] failed\n", __func__, voltdm->name);
>> > + omap_vp_disable(voltdm);
>> > + return r;
>> > + }
>> > + work_data->vdata = volt_data;
>> > + work_data->work_active = true;
>> > + work_data->num_calib_triggers = 0;
>> > + /* program the workqueue and leave it to calibrate offline.. */
>> > + schedule_delayed_work(&work_data->work,
>> > + msecs_to_jiffies(SR1P5_SAMPLING_DELAY_MS *
>> > + SR1P5_STABLE_SAMPLES));
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_disable() - disable for class 1p5
>> > + * @voltdm: voltage domain for the sr which needs disabling
>> > + * @volt_data: voltagedata to disable
>> > + * @is_volt_reset: reset the voltage?
>> > + *
>> > + * we dont do anything if the class 1p5 is being used. this is because we
>> > + * already disable sr at the end of calibration and no h/w loop is actually
>> > + * active when this is called.
>> > + */
>> > +static int sr_class1p5_disable(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *volt_data,
>> > + int is_volt_reset)
>> > +{
>> > + struct sr_class1p5_work_data *work_data;
>> > +
>> > + work_data = get_sr1p5_work(voltdm);
>> > + if (work_data->work_active) {
>> > + /* if volt reset and work is active, we dont allow this */
>> > + if (is_volt_reset)
>> > + return -EBUSY;
>> > + /* flag work is dead and remove the old work */
>> > + work_data->work_active = false;
>> > + cancel_delayed_work_sync(&work_data->work);
>> > + sr_notifier_control(voltdm, false);
>> > + omap_vp_disable(voltdm);
>> > + sr_disable(voltdm);
>> > + }
>> > +
>> > + /* if already calibrated, nothin special to do here.. */
>> > + if (volt_data->volt_calibrated)
>> > + return 0;
>> > +
>> > + if (is_volt_reset)
>> > + omap_voltage_reset(voltdm);
>> > + return 0;
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_configure() - configuration function
>> > + * @voldm: configure for which voltage domain
>> > + *
>> > + * we dont do much here other than setup some registers for
>> > + * the sr module involved.
>> > + */
>> > +static int sr_class1p5_configure(struct voltagedomain *voltdm)
>> > +{
>> > + return sr_configure_errgen(voltdm);
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_reset_calib() - reset all calibrated voltages
>> > + * @srid: srid to reset the calibration for
>> > + * @reset: reset voltage before we recal?
>> > + * @recal: should I recalibrate my current opp?
>> > + *
>> > + * if we call this, it means either periodic calibration trigger was
>> > + * fired(either from sysfs or other mechanisms) or we have disabled class 1p5,
>> > + * meaning we cant trust the calib voltages anymore, it is better to use
>> > + * nominal in the system
>> > + */
>> > +static void sr_class1p5_reset_calib(struct voltagedomain *voltdm, bool reset,
>> > + bool recal)
>> > +{
>> > + struct sr_class1p5_work_data *work_data;
>> > +
>> > + /* I dont need to go further if sr is not present */
>> > + if (!is_sr_enabled(voltdm))
>> > + return;
>> > +
>> > + work_data = get_sr1p5_work(voltdm);
>> > +
>> > + if (work_data->work_active)
>> > + sr_class1p5_disable(voltdm, work_data->vdata, 0);
>> > +
>> > + omap_voltage_calib_reset(voltdm);
>> > +
>> > + /*
>> > + * I should now reset the voltages to my nominal to be safe
>> > + */
>> > + if (reset)
>> > + omap_voltage_reset(voltdm);
>> > +
>> > + /*
>> > + * I should fire a recalibration for current opp if needed
>> > + * Note: i have just reset my calibrated voltages, and if
>> > + * i call sr_enable equivalent, I will cause a recalibration
>> > + * loop, even though the function is called sr_enable.. we
>> > + * are in class 1.5 ;)
>> > + */
>> > + if (reset && recal)
>> > + sr_class1p5_enable(voltdm, work_data->vdata);
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_cinit() - class 1p5 init
>> > + * @voltdm: sr voltage domain
>> > + * @class_priv_data: private data for the class
>> > + *
>> > + * we do class specific initialization like creating sysfs/debugfs entries
>> > + * needed, spawning of a kthread if needed etc.
>> > + */
>> > +static int sr_class1p5_cinit(struct voltagedomain *voltdm,
>> > + void *class_priv_data)
>> > +{
>> > + struct sr_class1p5_work_data *work_data;
>> > + int idx;
>> > +
>> > + if (!class_priv_data) {
>> > + pr_err("%s: bad param? no priv data!\n", __func__);
>> > + return -EINVAL;
>> > + }
>> > +
>> > + /* setup our work params */
>> > + work_data = get_sr1p5_work(voltdm);
>> > + if (!IS_ERR_OR_NULL(work_data)) {
>> > + pr_err("%s: ooopps.. class already initialized for %s! bug??\n",
>> > + __func__, voltdm->name);
>> > + return -EINVAL;
>> > + }
>> > + work_data = NULL;
>> > + /* get the next spare work_data */
>> > + for (idx = 0; idx < MAX_VDDS; idx++) {
>> > + if (!class_1p5_data.work_data[idx].voltdm) {
>> > + work_data = &class_1p5_data.work_data[idx];
>> > + break;
>> > + }
>> > + }
>> > + if (!work_data) {
>> > + pr_err("%s: no more space for work data for domains!\n",
>> > + __func__);
>> > + return -ENOMEM;
>> > + }
>> > + work_data->voltdm = voltdm;
>> > + INIT_DELAYED_WORK_DEFERRABLE(&work_data->work, do_calibrate);
>> > + return 0;
>> > +}
>> > +
>> > +/**
>> > + * sr_class1p5_cdeinit() - class 1p5 deinitialization
>> > + * @voltdm: voltage domain for which to do this.
>> > + * @class_priv_data: class private data for deinitialiation
>> > + *
>> > + * currently only resets the calibrated voltage forcing dvfs voltages
>> > + * to be used in the system
>> > + */
>> > +static int sr_class1p5_cdeinit(struct voltagedomain *voltdm,
>> > + void *class_priv_data)
>> > +{
>> > + struct sr_class1p5_work_data *work_data;
>> > +
>> > + /* setup our work params */
>> > + work_data = get_sr1p5_work(voltdm);
>> > + if (IS_ERR_OR_NULL(work_data)) {
>> > + pr_err("%s: ooopps.. class not initialized for %s! bug??\n",
>> > + __func__, voltdm->name);
>> > + return -EINVAL;
>> > + }
>> > +
>> > + /*
>> > + * we dont have SR periodic calib anymore.. so reset calibs
>> > + * we are already protected by sr debugfs lock, so no lock needed
>> > + * here.
>> > + */
>> > + sr_class1p5_reset_calib(voltdm, true, false);
>> > +
>> > + /* reset all data for this work data */
>> > + memset(work_data, 0, sizeof(*work_data));
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +/* SR class1p5 structure */
>> > +static struct omap_sr_class_data class1p5_data = {
>> > + .enable = sr_class1p5_enable,
>> > + .disable = sr_class1p5_disable,
>> > + .configure = sr_class1p5_configure,
>> > + .class_type = SR_CLASS1P5,
>> > + .class_init = sr_class1p5_cinit,
>> > + .class_deinit = sr_class1p5_cdeinit,
>> > + .notify = sr_class1p5_notify,
>> > + /*
>> > + * trigger for bound - this tells VP that SR has a voltage
>> > + * change. we should ensure transdone is set before reading
>> > + * vp voltage.
>> > + */
>> > + .notify_flags = SR_NOTIFY_MCUBOUND,
>> > + .class_priv_data = (void *)&class_1p5_data,
>> > +};
>> > +
>> > +/**
>> > + * sr_class1p5_init() - register class 1p5 as default
>> > + *
>> > + * board files call this function to use class 1p5, we register with the
>> > + * smartreflex subsystem
>> > + */
>> > +static int __init sr_class1p5_init(void)
>> > +{
>> > + int r;
>> > +
>> > + /* Enable this class only for OMAP3630 and OMAP4 */
>> > + if (!(cpu_is_omap3630() || cpu_is_omap44xx()))
>> > + return -EINVAL;
>> > +
>> > + r = sr_register_class(&class1p5_data);
>> > + if (r) {
>> > + pr_err("SmartReflex class 1.5 driver: "
>> > + "failed to register with %d\n", r);
>> > + } else {
>> > +#if CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY
>> > + INIT_DELAYED_WORK_DEFERRABLE(&recal_work, do_recalibrate);
>> > + schedule_delayed_work(&recal_work, msecs_to_jiffies(
>> > + CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY));
>> > +#endif
>> > + pr_info("SmartReflex class 1.5 driver: initialized (%dms)\n",
>> > + CONFIG_OMAP_SR_CLASS1P5_RECALIBRATION_DELAY);
>> > + }
>> > + return r;
>> > +}
>> > +late_initcall(sr_class1p5_init);
>> > diff --git a/arch/arm/mach-omap2/smartreflex-class3.c b/arch/arm/mach-omap2/smartreflex-class3.c
>> > index 7ac88da..5f7a33e 100644
>> > --- a/arch/arm/mach-omap2/smartreflex-class3.c
>> > +++ b/arch/arm/mach-omap2/smartreflex-class3.c
>> > @@ -21,7 +21,9 @@ static int sr_class3_enable(struct voltagedomain *voltdm,
>> > return sr_enable(voltdm, volt_data);
>> > }
>> >
>> > -static int sr_class3_disable(struct voltagedomain *voltdm, int is_volt_reset)
>> > +static int sr_class3_disable(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *vdata,
>> > + int is_volt_reset)
>> > {
>> > omap_vp_disable(voltdm);
>> > sr_disable(voltdm);
>> > diff --git a/arch/arm/mach-omap2/smartreflex.c b/arch/arm/mach-omap2/smartreflex.c
>> > index 3a5f2f6..bb55b65 100644
>> > --- a/arch/arm/mach-omap2/smartreflex.c
>> > +++ b/arch/arm/mach-omap2/smartreflex.c
>> > @@ -317,7 +317,9 @@ static void sr_stop_vddautocomp(struct omap_sr *sr)
>> > }
>> >
>> > if (sr->autocomp_active) {
>> > - sr_class->disable(sr->voltdm, 1);
>> > + sr_class->disable(sr->voltdm,
>> > + omap_voltage_get_nom_volt(sr->voltdm),
>> > + 1);
>> > if (sr_class->class_deinit &&
>> > sr_class->class_deinit(sr->voltdm,
>> > sr_class->class_priv_data)) {
>> > @@ -471,6 +473,28 @@ static u32 sr_retrieve_nvalue(struct omap_sr *sr, u32 efuse_offs)
>> > /* Public Functions */
>> >
>> > /**
>> > + * is_sr_enabled() - is Smart reflex enabled for this domain?
>> > + * @voltdm: voltage domain to check
>> > + *
>> > + * Returns 0 if SR is enabled for this domain, else returns err
>> > + */
>> > +bool is_sr_enabled(struct voltagedomain *voltdm)
>> > +{
>> > + struct omap_sr *sr;
>> > + if (IS_ERR_OR_NULL(voltdm)) {
>> > + pr_warning("%s: invalid param voltdm\n", __func__);
>> > + return false;
>> > + }
>> > + sr = _sr_lookup(voltdm);
>> > + if (IS_ERR(sr)) {
>> > + pr_warning("%s: omap_sr struct for sr_%s not found\n",
>> > + __func__, voltdm->name);
>> > + return false;
>> > + }
>> > + return sr->autocomp_active;
>> > +}
>> > +
>> > +/**
>> > * sr_configure_errgen() - Configures the smrtreflex to perform AVS using the
>> > * error generator module.
>> > * @voltdm: VDD pointer to which the SR module to be configured belongs to.
>> > @@ -839,6 +863,7 @@ void omap_sr_enable(struct voltagedomain *voltdm,
>> > * omap_sr_disable() - API to disable SR without resetting the voltage
>> > * processor voltage
>> > * @voltdm: VDD pointer to which the SR module to be configured belongs to.
>> > + * @volt_data: Voltage data to go to
>> > *
>> > * This API is to be called from the kernel in order to disable
>> > * a particular smartreflex module. This API will in turn call
>> > @@ -846,7 +871,8 @@ void omap_sr_enable(struct voltagedomain *voltdm,
>> > * the smartreflex class disable not to reset the VP voltage after
>> > * disabling smartreflex.
>> > */
>> > -void omap_sr_disable(struct voltagedomain *voltdm)
>> > +void omap_sr_disable(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *vdata)
>> > {
>> > struct omap_sr *sr = _sr_lookup(voltdm);
>> >
>> > @@ -865,7 +891,7 @@ void omap_sr_disable(struct voltagedomain *voltdm)
>> > return;
>> > }
>> >
>> > - sr_class->disable(voltdm, 0);
>> > + sr_class->disable(voltdm, vdata, 0);
>> > }
>> >
>> > /**
>> > @@ -898,7 +924,7 @@ void omap_sr_disable_reset_volt(struct voltagedomain *voltdm)
>> > return;
>> > }
>> >
>> > - sr_class->disable(voltdm, 1);
>> > + sr_class->disable(voltdm, omap_voltage_get_nom_volt(voltdm), 1);
>> > }
>> >
>> > /**
>> > diff --git a/arch/arm/mach-omap2/voltage.c b/arch/arm/mach-omap2/voltage.c
>> > index 77cb0cd..c451835 100644
>> > --- a/arch/arm/mach-omap2/voltage.c
>> > +++ b/arch/arm/mach-omap2/voltage.c
>> > @@ -374,9 +374,45 @@ static int nom_volt_debug_get(void *data, u64 *val)
>> > return 0;
>> > }
>> >
>> > +static int dyn_volt_debug_get(void *data, u64 *val)
>> > +{
>> > + struct omap_vdd_info *vdd = (struct omap_vdd_info *) data;
>> > + struct omap_volt_data *volt_data;
>> > +
>> > + if (!vdd) {
>> > + pr_warning("Wrong paramater passed\n");
>> > + return -EINVAL;
>> > + }
>> > + volt_data = omap_voltage_get_nom_volt(&vdd->voltdm);
>> > +
>> > + *val = volt_data->volt_dynamic_nominal;
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +static int calib_volt_debug_get(void *data, u64 *val)
>> > +{
>> > + struct omap_vdd_info *vdd = (struct omap_vdd_info *) data;
>> > + struct omap_volt_data *volt_data;
>> > +
>> > + if (!vdd) {
>> > + pr_warning("Wrong paramater passed\n");
>> > + return -EINVAL;
>> > + }
>> > + volt_data = omap_voltage_get_nom_volt(&vdd->voltdm);
>> > +
>> > + *val = volt_data->volt_calibrated;
>> > +
>> > + return 0;
>> > +}
>> > +
>> > DEFINE_SIMPLE_ATTRIBUTE(vp_volt_debug_fops, vp_volt_debug_get, NULL, "%llu\n");
>> > DEFINE_SIMPLE_ATTRIBUTE(nom_volt_debug_fops, nom_volt_debug_get, NULL,
>> > "%llu\n");
>> > +DEFINE_SIMPLE_ATTRIBUTE(dyn_volt_debug_fops, dyn_volt_debug_get, NULL,
>> > + "%llu\n");
>> > +DEFINE_SIMPLE_ATTRIBUTE(calib_volt_debug_fops, calib_volt_debug_get, NULL,
>> > + "%llu\n");
>> > static void vp_latch_vsel(struct omap_vdd_info *vdd)
>> > {
>> > u32 vpconfig;
>> > @@ -504,6 +540,12 @@ static void __init vdd_debugfs_init(struct omap_vdd_info *vdd)
>> > (void) debugfs_create_file("curr_nominal_volt", S_IRUGO,
>> > vdd->debug_dir, (void *) vdd,
>> > &nom_volt_debug_fops);
>> > + (void) debugfs_create_file("curr_dyn_nominal_volt", S_IRUGO,
>> > + vdd->debug_dir, (void *) vdd,
>> > + &dyn_volt_debug_fops);
>> > + (void) debugfs_create_file("curr_calibrated_volt", S_IRUGO,
>> > + vdd->debug_dir, (void *) vdd,
>> > + &calib_volt_debug_fops);
>> > }
>> >
>> > /* Voltage scale and accessory APIs */
>> > @@ -1132,6 +1174,33 @@ struct omap_volt_data *omap_voltage_get_nom_volt(struct voltagedomain *voltdm)
>> > }
>> >
>> > /**
>> > + * omap_voltage_calib_reset() - reset the calibrated voltage entries
>> > + * @voltdm: voltage domain to reset the entries for
>> > + *
>> > + * when the calibrated entries are no longer valid, this api allows
>> > + * the calibrated voltages to be reset.
>> > + */
>> > +int omap_voltage_calib_reset(struct voltagedomain *voltdm)
>> > +{
>> > + struct omap_vdd_info *vdd;
>> > + struct omap_volt_data *volt_data;
>> > +
>> > + if (IS_ERR_OR_NULL(voltdm)) {
>> > + pr_warning("%s: VDD specified does not exist!\n", __func__);
>> > + return -EINVAL;
>> > + }
>> > +
>> > + vdd = container_of(voltdm, struct omap_vdd_info, voltdm);
>> > + volt_data = vdd->volt_data;
>> > + /* reset the calibrated voltages as 0 */
>> > + while (volt_data->volt_nominal) {
>> > + volt_data->volt_calibrated = 0;
>> > + volt_data++;
>> > + }
>> > + return 0;
>> > +}
>> > +
>> > +/**
>> > * omap_vp_get_curr_volt() - API to get the current vp voltage.
>> > * @voltdm: pointer to the VDD.
>> > *
>> > diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
>> > index b6333ae..dba7939 100644
>> > --- a/arch/arm/plat-omap/Kconfig
>> > +++ b/arch/arm/plat-omap/Kconfig
>> > @@ -67,6 +67,23 @@ config OMAP_SMARTREFLEX_CLASS3
>> > Class 3 implementation of Smartreflex employs continuous hardware
>> > voltage calibration.
>> >
>> > +config OMAP_SMARTREFLEX_CLASS1P5
>> > + bool "Class 1.5 mode of Smartreflex Implementation"
>> > + depends on OMAP_SMARTREFLEX && TWL4030_CORE
>> > + help
>> > + Say Y to enable Class 1.5 implementation of Smartreflex
>> > + Class 1.5 implementation of Smartreflex employs software controlled
>> > + hardware voltage calibration.
>> > +
>> > +config OMAP_SR_CLASS1P5_RECALIBRATION_DELAY
>> > + int "Class 1.5 mode recalibration recalibration delay(ms)"
>> > + depends on OMAP_SMARTREFLEX_CLASS1P5
>> > + default 86400000
>> > + help
>> > + Setup the recalibration delay in milliseconds. Use 0 for never doing
>> > + a recalibration. Defaults to recommended recalibration every 24hrs.
>> > + If you do not understand this, use the default.
>> > +
>> > config OMAP_RESET_CLOCKS
>> > bool "Reset unused clocks during boot"
>> > depends on ARCH_OMAP
>> > diff --git a/arch/arm/plat-omap/include/plat/smartreflex.h b/arch/arm/plat-omap/include/plat/smartreflex.h
>> > index 07f35b2..ee5c58f 100644
>> > --- a/arch/arm/plat-omap/include/plat/smartreflex.h
>> > +++ b/arch/arm/plat-omap/include/plat/smartreflex.h
>> > @@ -167,6 +167,7 @@ struct omap_sr_pmic_data {
>> > #define SR_CLASS1 0x1
>> > #define SR_CLASS2 0x2
>> > #define SR_CLASS3 0x3
>> > +#define SR_CLASS1P5 0x4
>> >
>> > /**
>> > * struct omap_sr_class_data - Smartreflex class driver info
>> > @@ -187,7 +188,9 @@ struct omap_sr_pmic_data {
>> > struct omap_sr_class_data {
>> > int (*enable)(struct voltagedomain *voltdm,
>> > struct omap_volt_data *volt_data);
>> > - int (*disable)(struct voltagedomain *voltdm, int is_volt_reset);
>> > + int (*disable)(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *volt_data,
>> > + int is_volt_reset);
>> > int (*class_init)(struct voltagedomain *voltdm, void *class_priv_data);
>> > int (*class_deinit)(struct voltagedomain *voltdm,
>> > void *class_priv_data);
>> > @@ -235,7 +238,8 @@ struct omap_sr_data {
>> > /* Smartreflex module enable/disable interface */
>> > void omap_sr_enable(struct voltagedomain *voltdm,
>> > struct omap_volt_data *volt_data);
>> > -void omap_sr_disable(struct voltagedomain *voltdm);
>> > +void omap_sr_disable(struct voltagedomain *voltdm,
>> > + struct omap_volt_data *volt_data);
>> > void omap_sr_disable_reset_volt(struct voltagedomain *voltdm);
>> >
>> > /* API to register the pmic specific data with the smartreflex driver. */
>> > @@ -250,6 +254,7 @@ int sr_configure_minmax(struct voltagedomain *voltdm);
>> >
>> > /* API to register the smartreflex class driver with the smartreflex driver */
>> > int sr_register_class(struct omap_sr_class_data *class_data);
>> > +bool is_sr_enabled(struct voltagedomain *voltdm);
>> > #else
>> > static inline void omap_sr_enable(struct voltagedomain *voltdm) {}
>> > static inline void omap_sr_disable(struct voltagedomain *voltdm) {}
>> > @@ -264,5 +269,9 @@ static inline void omap_sr_disable_reset_volt(
>> > struct voltagedomain *voltdm) {}
>> > static inline void omap_sr_register_pmic(
>> > struct omap_sr_pmic_data *pmic_data) {}
>> > +static inline bool is_sr_enabled(struct voltagedomain *voltdm)
>> > +{
>> > + return false;
>> > +}
>> > #endif
>> > #endif
>> > diff --git a/arch/arm/plat-omap/include/plat/voltage.h b/arch/arm/plat-omap/include/plat/voltage.h
>> > index 332c581..54445f0 100644
>> > --- a/arch/arm/plat-omap/include/plat/voltage.h
>> > +++ b/arch/arm/plat-omap/include/plat/voltage.h
>> > @@ -58,6 +58,8 @@
>> > #define OMAP4430_VDD_CORE_OPP50_UV 930000
>> > #define OMAP4430_VDD_CORE_OPP100_UV 1100000
>> >
>> > +#define OMAP3PLUS_DYNAMIC_NOMINAL_MARGIN_UV 50000
>> > +
>> > /**
>> > * struct voltagedomain - omap voltage domain global structure.
>> > * @name: Name of the voltage domain which can be used as a unique
>> > @@ -81,6 +83,8 @@ struct voltagedomain {
>> > */
>> > struct omap_volt_data {
>> > u32 volt_nominal;
>> > + u32 volt_calibrated;
>> > + u32 volt_dynamic_nominal;
>> > u32 sr_efuse_offs;
>> > u8 sr_errminlimit;
>> > u8 vp_errgain;
>> > @@ -127,6 +131,7 @@ struct omap_volt_data *omap_voltage_get_nom_volt(struct voltagedomain *voltdm);
>> > bool omap_vp_is_transdone(struct voltagedomain *voltdm);
>> > bool omap_vp_clear_transdone(struct voltagedomain *voltdm);
>> > struct dentry *omap_voltage_get_dbgdir(struct voltagedomain *voltdm);
>> > +int omap_voltage_calib_reset(struct voltagedomain *voltdm);
>> > #ifdef CONFIG_PM
>> > int omap_voltage_register_pmic(struct voltagedomain *voltdm,
>> > struct omap_volt_pmic_info *pmic_info);
>> > @@ -160,7 +165,23 @@ static inline unsigned long omap_get_operation_voltage(
>> > {
>> > if (IS_ERR_OR_NULL(vdata))
>> > return 0;
>> > - return vdata->volt_nominal;
>> > + return (vdata->volt_calibrated) ? vdata->volt_calibrated :
>> > + (vdata->volt_dynamic_nominal) ? vdata->volt_dynamic_nominal :
>> > + vdata->volt_nominal;
>> > }
>> >
>> > +/* what is my dynamic nominal? */
>> > +static inline unsigned long omap_get_dyn_nominal(struct omap_volt_data *vdata)
>> > +{
>> > + if (IS_ERR_OR_NULL(vdata))
>> > + return 0;
>> > + if (vdata->volt_calibrated) {
>> > + unsigned long v = vdata->volt_calibrated +
>> > + OMAP3PLUS_DYNAMIC_NOMINAL_MARGIN_UV;
>> > + if (v > vdata->volt_nominal)
>> > + return vdata->volt_nominal;
>> > + return v;
>> > + }
>> > + return vdata->volt_nominal;
>> > +}
>> > #endif
>> > --
>> > 1.7.1
>> >
>> > --
>> > To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>> > the body of a message to majordomo@xxxxxxxxxxxxxxx
>> > More majordomo info at http://vger.kernel.org/majordomo-info.html
>> >
>> I have tested this Patch Series on OMAP 3630 SDP, for MPU and IVA Powerdomains
> Could you clarify on null pointer issue: on SDP3630? or OMAP4SDP? I
> see there is a risk with OMAP4 where there is a bug in the following
> scenario:
> bootloader setups the OPP frequency for an OPP(e.g. 1GHz) which is
> disabled by default on OPP table in kernel. this needs to be cleanly
> fixed in pm.c, at the same time, the exposed functions in class1p5
> needs parameter validation as well.
Sorry, it is reproduced on OMAP 4430 SDP.
>> it throws error log "Unable to refer to NULL pointer" if
>> curr_nominal_volt, curr_calibrated_volt
>> or curr_dynamical_volt is accessed through debugfs.
>> Could you please provide fix for this.
>
>
> Regards,
> Nishanth Menon
>
--
Thanks,
Regards,
Shweta
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