diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-07-03 14:35:40 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-07-03 14:35:40 -0700 |
commit | f991fae5c6d42dfc5029150b05a78cf3f6c18cc9 (patch) | |
tree | d140deb437bde0631778b4984eeb72c1f4ee0c1d /drivers/devfreq/exynos/exynos5_bus.c | |
parent | d4141531f63a29bb2a980092b6f2828c385e6edd (diff) | |
parent | 2c843bd92ec276ecb68504b3b5ffa7066183f032 (diff) | |
download | op-kernel-dev-f991fae5c6d42dfc5029150b05a78cf3f6c18cc9.zip op-kernel-dev-f991fae5c6d42dfc5029150b05a78cf3f6c18cc9.tar.gz |
Merge tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael Wysocki:
"This time the total number of ACPI commits is slightly greater than
the number of cpufreq commits, but Viresh Kumar (who works on cpufreq)
remains the most active patch submitter.
To me, the most significant change is the addition of offline/online
device operations to the driver core (with the Greg's blessing) and
the related modifications of the ACPI core hotplug code. Next are the
freezer updates from Colin Cross that should make the freezing of
tasks a bit less heavy weight.
We also have a couple of regression fixes, a number of fixes for
issues that have not been identified as regressions, two new drivers
and a bunch of cleanups all over.
Highlights:
- Hotplug changes to support graceful hot-removal failures.
It sometimes is necessary to fail device hot-removal operations
gracefully if they cannot be carried out completely. For example,
if memory from a memory module being hot-removed has been allocated
for the kernel's own use and cannot be moved elsewhere, it's
desirable to fail the hot-removal operation in a graceful way
rather than to crash the kernel, but currenty a success or a kernel
crash are the only possible outcomes of an attempted memory
hot-removal. Needless to say, that is not a very attractive
alternative and it had to be addressed.
However, in order to make it work for memory, I first had to make
it work for CPUs and for this purpose I needed to modify the ACPI
processor driver. It's been split into two parts, a resident one
handling the low-level initialization/cleanup and a modular one
playing the actual driver's role (but it binds to the CPU system
device objects rather than to the ACPI device objects representing
processors). That's been sort of like a live brain surgery on a
patient who's riding a bike.
So this is a little scary, but since we found and fixed a couple of
regressions it caused to happen during the early linux-next testing
(a month ago), nobody has complained.
As a bonus we remove some duplicated ACPI hotplug code, because the
ACPI-based CPU hotplug is now going to use the common ACPI hotplug
code.
- Lighter weight freezing of tasks.
These changes from Colin Cross and Mandeep Singh Baines are
targeted at making the freezing of tasks a bit less heavy weight
operation. They reduce the number of tasks woken up every time
during the freezing, by using the observation that the freezer
simply doesn't need to wake up some of them and wait for them all
to call refrigerator(). The time needed for the freezer to decide
to report a failure is reduced too.
Also reintroduced is the check causing a lockdep warining to
trigger when try_to_freeze() is called with locks held (which is
generally unsafe and shouldn't happen).
- cpufreq updates
First off, a commit from Srivatsa S Bhat fixes a resume regression
introduced during the 3.10 cycle causing some cpufreq sysfs
attributes to return wrong values to user space after resume. The
fix is kind of fresh, but also it's pretty obvious once Srivatsa
has identified the root cause.
Second, we have a new freqdomain_cpus sysfs attribute for the
acpi-cpufreq driver to provide information previously available via
related_cpus. From Lan Tianyu.
Finally, we fix a number of issues, mostly related to the
CPUFREQ_POSTCHANGE notifier and cpufreq Kconfig options and clean
up some code. The majority of changes from Viresh Kumar with bits
from Jacob Shin, Heiko Stübner, Xiaoguang Chen, Ezequiel Garcia,
Arnd Bergmann, and Tang Yuantian.
- ACPICA update
A usual bunch of updates from the ACPICA upstream.
During the 3.4 cycle we introduced support for ACPI 5 extended
sleep registers, but they are only supposed to be used if the
HW-reduced mode bit is set in the FADT flags and the code attempted
to use them without checking that bit. That caused suspend/resume
regressions to happen on some systems. Fix from Lv Zheng causes
those registers to be used only if the HW-reduced mode bit is set.
Apart from this some other ACPICA bugs are fixed and code cleanups
are made by Bob Moore, Tomasz Nowicki, Lv Zheng, Chao Guan, and
Zhang Rui.
- cpuidle updates
New driver for Xilinx Zynq processors is added by Michal Simek.
Multidriver support simplification, addition of some missing
kerneldoc comments and Kconfig-related fixes come from Daniel
Lezcano.
- ACPI power management updates
Changes to make suspend/resume work correctly in Xen guests from
Konrad Rzeszutek Wilk, sparse warning fix from Fengguang Wu and
cleanups and fixes of the ACPI device power state selection
routine.
- ACPI documentation updates
Some previously missing pieces of ACPI documentation are added by
Lv Zheng and Aaron Lu (hopefully, that will help people to
uderstand how the ACPI subsystem works) and one outdated doc is
updated by Hanjun Guo.
- Assorted ACPI updates
We finally nailed down the IA-64 issue that was the reason for
reverting commit 9f29ab11ddbf ("ACPI / scan: do not match drivers
against objects having scan handlers"), so we can fix it and move
the ACPI scan handler check added to the ACPI video driver back to
the core.
A mechanism for adding CMOS RTC address space handlers is
introduced by Lan Tianyu to allow some EC-related breakage to be
fixed on some systems.
A spec-compliant implementation of acpi_os_get_timer() is added by
Mika Westerberg.
The evaluation of _STA is added to do_acpi_find_child() to avoid
situations in which a pointer to a disabled device object is
returned instead of an enabled one with the same _ADR value. From
Jeff Wu.
Intel BayTrail PCH (Platform Controller Hub) support is added to
the ACPI driver for Intel Low-Power Subsystems (LPSS) and that
driver is modified to work around a couple of known BIOS issues.
Changes from Mika Westerberg and Heikki Krogerus.
The EC driver is fixed by Vasiliy Kulikov to use get_user() and
put_user() instead of dereferencing user space pointers blindly.
Code cleanups are made by Bjorn Helgaas, Nicholas Mazzuca and Toshi
Kani.
- Assorted power management updates
The "runtime idle" helper routine is changed to take the return
values of the callbacks executed by it into account and to call
rpm_suspend() if they return 0, which allows us to reduce the
overall code bloat a bit (by dropping some code that's not
necessary any more after that modification).
The runtime PM documentation is updated by Alan Stern (to reflect
the "runtime idle" behavior change).
New trace points for PM QoS are added by Sahara
(<keun-o.park@windriver.com>).
PM QoS documentation is updated by Lan Tianyu.
Code cleanups are made and minor issues are addressed by Bernie
Thompson, Bjorn Helgaas, Julius Werner, and Shuah Khan.
- devfreq updates
New driver for the Exynos5-bus device from Abhilash Kesavan.
Minor cleanups, fixes and MAINTAINERS update from MyungJoo Ham,
Abhilash Kesavan, Paul Bolle, Rajagopal Venkat, and Wei Yongjun.
- OMAP power management updates
Adaptive Voltage Scaling (AVS) SmartReflex voltage control driver
updates from Andrii Tseglytskyi and Nishanth Menon."
* tag 'pm+acpi-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits)
cpufreq: Fix cpufreq regression after suspend/resume
ACPI / PM: Fix possible NULL pointer deref in acpi_pm_device_sleep_state()
PM / Sleep: Warn about system time after resume with pm_trace
cpufreq: don't leave stale policy pointer in cdbs->cur_policy
acpi-cpufreq: Add new sysfs attribute freqdomain_cpus
cpufreq: make sure frequency transitions are serialized
ACPI: implement acpi_os_get_timer() according the spec
ACPI / EC: Add HP Folio 13 to ec_dmi_table in order to skip DSDT scan
ACPI: Add CMOS RTC Operation Region handler support
ACPI / processor: Drop unused variable from processor_perflib.c
cpufreq: tegra: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: s3c64xx: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: omap: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: imx6q: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: exynos: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: dbx500: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: davinci: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: arm-big-little: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: powernow-k8: call CPUFREQ_POSTCHANGE notfier in error cases
cpufreq: pcc: call CPUFREQ_POSTCHANGE notfier in error cases
...
Diffstat (limited to 'drivers/devfreq/exynos/exynos5_bus.c')
-rw-r--r-- | drivers/devfreq/exynos/exynos5_bus.c | 503 |
1 files changed, 503 insertions, 0 deletions
diff --git a/drivers/devfreq/exynos/exynos5_bus.c b/drivers/devfreq/exynos/exynos5_bus.c new file mode 100644 index 0000000..574b16b --- /dev/null +++ b/drivers/devfreq/exynos/exynos5_bus.c @@ -0,0 +1,503 @@ +/* + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * EXYNOS5 INT clock frequency scaling support using DEVFREQ framework + * Based on work done by Jonghwan Choi <jhbird.choi@samsung.com> + * Support for only EXYNOS5250 is present. + * + * 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/module.h> +#include <linux/devfreq.h> +#include <linux/io.h> +#include <linux/opp.h> +#include <linux/slab.h> +#include <linux/suspend.h> +#include <linux/opp.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/pm_qos.h> +#include <linux/regulator/consumer.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> + +#include "exynos_ppmu.h" + +#define MAX_SAFEVOLT 1100000 /* 1.10V */ +/* Assume that the bus is saturated if the utilization is 25% */ +#define INT_BUS_SATURATION_RATIO 25 + +enum int_level_idx { + LV_0, + LV_1, + LV_2, + LV_3, + LV_4, + _LV_END +}; + +enum exynos_ppmu_list { + PPMU_RIGHT, + PPMU_END, +}; + +struct busfreq_data_int { + struct device *dev; + struct devfreq *devfreq; + struct regulator *vdd_int; + struct exynos_ppmu ppmu[PPMU_END]; + unsigned long curr_freq; + bool disabled; + + struct notifier_block pm_notifier; + struct mutex lock; + struct pm_qos_request int_req; + struct clk *int_clk; +}; + +struct int_bus_opp_table { + unsigned int idx; + unsigned long clk; + unsigned long volt; +}; + +static struct int_bus_opp_table exynos5_int_opp_table[] = { + {LV_0, 266000, 1025000}, + {LV_1, 200000, 1025000}, + {LV_2, 160000, 1025000}, + {LV_3, 133000, 1025000}, + {LV_4, 100000, 1025000}, + {0, 0, 0}, +}; + +static void busfreq_mon_reset(struct busfreq_data_int *data) +{ + unsigned int i; + + for (i = PPMU_RIGHT; i < PPMU_END; i++) { + void __iomem *ppmu_base = data->ppmu[i].hw_base; + + /* Reset the performance and cycle counters */ + exynos_ppmu_reset(ppmu_base); + + /* Setup count registers to monitor read/write transactions */ + data->ppmu[i].event[PPMU_PMNCNT3] = RDWR_DATA_COUNT; + exynos_ppmu_setevent(ppmu_base, PPMU_PMNCNT3, + data->ppmu[i].event[PPMU_PMNCNT3]); + + exynos_ppmu_start(ppmu_base); + } +} + +static void exynos5_read_ppmu(struct busfreq_data_int *data) +{ + int i, j; + + for (i = PPMU_RIGHT; i < PPMU_END; i++) { + void __iomem *ppmu_base = data->ppmu[i].hw_base; + + exynos_ppmu_stop(ppmu_base); + + /* Update local data from PPMU */ + data->ppmu[i].ccnt = __raw_readl(ppmu_base + PPMU_CCNT); + + for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) { + if (data->ppmu[i].event[j] == 0) + data->ppmu[i].count[j] = 0; + else + data->ppmu[i].count[j] = + exynos_ppmu_read(ppmu_base, j); + } + } + + busfreq_mon_reset(data); +} + +static int exynos5_int_setvolt(struct busfreq_data_int *data, + unsigned long volt) +{ + return regulator_set_voltage(data->vdd_int, volt, MAX_SAFEVOLT); +} + +static int exynos5_busfreq_int_target(struct device *dev, unsigned long *_freq, + u32 flags) +{ + int err = 0; + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct busfreq_data_int *data = platform_get_drvdata(pdev); + struct opp *opp; + unsigned long old_freq, freq; + unsigned long volt; + + rcu_read_lock(); + opp = devfreq_recommended_opp(dev, _freq, flags); + if (IS_ERR(opp)) { + rcu_read_unlock(); + dev_err(dev, "%s: Invalid OPP.\n", __func__); + return PTR_ERR(opp); + } + + freq = opp_get_freq(opp); + volt = opp_get_voltage(opp); + rcu_read_unlock(); + + old_freq = data->curr_freq; + + if (old_freq == freq) + return 0; + + dev_dbg(dev, "targetting %lukHz %luuV\n", freq, volt); + + mutex_lock(&data->lock); + + if (data->disabled) + goto out; + + if (freq > exynos5_int_opp_table[0].clk) + pm_qos_update_request(&data->int_req, freq * 16 / 1000); + else + pm_qos_update_request(&data->int_req, -1); + + if (old_freq < freq) + err = exynos5_int_setvolt(data, volt); + if (err) + goto out; + + err = clk_set_rate(data->int_clk, freq * 1000); + + if (err) + goto out; + + if (old_freq > freq) + err = exynos5_int_setvolt(data, volt); + if (err) + goto out; + + data->curr_freq = freq; +out: + mutex_unlock(&data->lock); + return err; +} + +static int exynos5_get_busier_dmc(struct busfreq_data_int *data) +{ + int i, j; + int busy = 0; + unsigned int temp = 0; + + for (i = PPMU_RIGHT; i < PPMU_END; i++) { + for (j = PPMU_PMNCNT0; j < PPMU_PMNCNT_MAX; j++) { + if (data->ppmu[i].count[j] > temp) { + temp = data->ppmu[i].count[j]; + busy = i; + } + } + } + + return busy; +} + +static int exynos5_int_get_dev_status(struct device *dev, + struct devfreq_dev_status *stat) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct busfreq_data_int *data = platform_get_drvdata(pdev); + int busier_dmc; + + exynos5_read_ppmu(data); + busier_dmc = exynos5_get_busier_dmc(data); + + stat->current_frequency = data->curr_freq; + + /* Number of cycles spent on memory access */ + stat->busy_time = data->ppmu[busier_dmc].count[PPMU_PMNCNT3]; + stat->busy_time *= 100 / INT_BUS_SATURATION_RATIO; + stat->total_time = data->ppmu[busier_dmc].ccnt; + + return 0; +} +static void exynos5_int_exit(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct busfreq_data_int *data = platform_get_drvdata(pdev); + + devfreq_unregister_opp_notifier(dev, data->devfreq); +} + +static struct devfreq_dev_profile exynos5_devfreq_int_profile = { + .initial_freq = 160000, + .polling_ms = 100, + .target = exynos5_busfreq_int_target, + .get_dev_status = exynos5_int_get_dev_status, + .exit = exynos5_int_exit, +}; + +static int exynos5250_init_int_tables(struct busfreq_data_int *data) +{ + int i, err = 0; + + for (i = LV_0; i < _LV_END; i++) { + err = opp_add(data->dev, exynos5_int_opp_table[i].clk, + exynos5_int_opp_table[i].volt); + if (err) { + dev_err(data->dev, "Cannot add opp entries.\n"); + return err; + } + } + + return 0; +} + +static int exynos5_busfreq_int_pm_notifier_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + struct busfreq_data_int *data = container_of(this, + struct busfreq_data_int, pm_notifier); + struct opp *opp; + unsigned long maxfreq = ULONG_MAX; + unsigned long freq; + unsigned long volt; + int err = 0; + + switch (event) { + case PM_SUSPEND_PREPARE: + /* Set Fastest and Deactivate DVFS */ + mutex_lock(&data->lock); + + data->disabled = true; + + rcu_read_lock(); + opp = opp_find_freq_floor(data->dev, &maxfreq); + if (IS_ERR(opp)) { + rcu_read_unlock(); + err = PTR_ERR(opp); + goto unlock; + } + freq = opp_get_freq(opp); + volt = opp_get_voltage(opp); + rcu_read_unlock(); + + err = exynos5_int_setvolt(data, volt); + if (err) + goto unlock; + + err = clk_set_rate(data->int_clk, freq * 1000); + + if (err) + goto unlock; + + data->curr_freq = freq; +unlock: + mutex_unlock(&data->lock); + if (err) + return NOTIFY_BAD; + return NOTIFY_OK; + case PM_POST_RESTORE: + case PM_POST_SUSPEND: + /* Reactivate */ + mutex_lock(&data->lock); + data->disabled = false; + mutex_unlock(&data->lock); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int exynos5_busfreq_int_probe(struct platform_device *pdev) +{ + struct busfreq_data_int *data; + struct opp *opp; + struct device *dev = &pdev->dev; + struct device_node *np; + unsigned long initial_freq; + unsigned long initial_volt; + int err = 0; + int i; + + data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data_int), + GFP_KERNEL); + if (data == NULL) { + dev_err(dev, "Cannot allocate memory.\n"); + return -ENOMEM; + } + + np = of_find_compatible_node(NULL, NULL, "samsung,exynos5250-ppmu"); + if (np == NULL) { + pr_err("Unable to find PPMU node\n"); + return -ENOENT; + } + + for (i = PPMU_RIGHT; i < PPMU_END; i++) { + /* map PPMU memory region */ + data->ppmu[i].hw_base = of_iomap(np, i); + if (data->ppmu[i].hw_base == NULL) { + dev_err(&pdev->dev, "failed to map memory region\n"); + return -ENOMEM; + } + } + data->pm_notifier.notifier_call = exynos5_busfreq_int_pm_notifier_event; + data->dev = dev; + mutex_init(&data->lock); + + err = exynos5250_init_int_tables(data); + if (err) + goto err_regulator; + + data->vdd_int = regulator_get(dev, "vdd_int"); + if (IS_ERR(data->vdd_int)) { + dev_err(dev, "Cannot get the regulator \"vdd_int\"\n"); + err = PTR_ERR(data->vdd_int); + goto err_regulator; + } + + data->int_clk = clk_get(dev, "int_clk"); + if (IS_ERR(data->int_clk)) { + dev_err(dev, "Cannot get clock \"int_clk\"\n"); + err = PTR_ERR(data->int_clk); + goto err_clock; + } + + rcu_read_lock(); + opp = opp_find_freq_floor(dev, + &exynos5_devfreq_int_profile.initial_freq); + if (IS_ERR(opp)) { + rcu_read_unlock(); + dev_err(dev, "Invalid initial frequency %lu kHz.\n", + exynos5_devfreq_int_profile.initial_freq); + err = PTR_ERR(opp); + goto err_opp_add; + } + initial_freq = opp_get_freq(opp); + initial_volt = opp_get_voltage(opp); + rcu_read_unlock(); + data->curr_freq = initial_freq; + + err = clk_set_rate(data->int_clk, initial_freq * 1000); + if (err) { + dev_err(dev, "Failed to set initial frequency\n"); + goto err_opp_add; + } + + err = exynos5_int_setvolt(data, initial_volt); + if (err) + goto err_opp_add; + + platform_set_drvdata(pdev, data); + + busfreq_mon_reset(data); + + data->devfreq = devfreq_add_device(dev, &exynos5_devfreq_int_profile, + "simple_ondemand", NULL); + + if (IS_ERR(data->devfreq)) { + err = PTR_ERR(data->devfreq); + goto err_devfreq_add; + } + + devfreq_register_opp_notifier(dev, data->devfreq); + + err = register_pm_notifier(&data->pm_notifier); + if (err) { + dev_err(dev, "Failed to setup pm notifier\n"); + goto err_devfreq_add; + } + + /* TODO: Add a new QOS class for int/mif bus */ + pm_qos_add_request(&data->int_req, PM_QOS_NETWORK_THROUGHPUT, -1); + + return 0; + +err_devfreq_add: + devfreq_remove_device(data->devfreq); + platform_set_drvdata(pdev, NULL); +err_opp_add: + clk_put(data->int_clk); +err_clock: + regulator_put(data->vdd_int); +err_regulator: + return err; +} + +static int exynos5_busfreq_int_remove(struct platform_device *pdev) +{ + struct busfreq_data_int *data = platform_get_drvdata(pdev); + + pm_qos_remove_request(&data->int_req); + unregister_pm_notifier(&data->pm_notifier); + devfreq_remove_device(data->devfreq); + regulator_put(data->vdd_int); + clk_put(data->int_clk); + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static int exynos5_busfreq_int_resume(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct busfreq_data_int *data = platform_get_drvdata(pdev); + + busfreq_mon_reset(data); + return 0; +} + +static const struct dev_pm_ops exynos5_busfreq_int_pm = { + .resume = exynos5_busfreq_int_resume, +}; + +/* platform device pointer for exynos5 devfreq device. */ +static struct platform_device *exynos5_devfreq_pdev; + +static struct platform_driver exynos5_busfreq_int_driver = { + .probe = exynos5_busfreq_int_probe, + .remove = exynos5_busfreq_int_remove, + .driver = { + .name = "exynos5-bus-int", + .owner = THIS_MODULE, + .pm = &exynos5_busfreq_int_pm, + }, +}; + +static int __init exynos5_busfreq_int_init(void) +{ + int ret; + + ret = platform_driver_register(&exynos5_busfreq_int_driver); + if (ret < 0) + goto out; + + exynos5_devfreq_pdev = + platform_device_register_simple("exynos5-bus-int", -1, NULL, 0); + if (IS_ERR_OR_NULL(exynos5_devfreq_pdev)) { + ret = PTR_ERR(exynos5_devfreq_pdev); + goto out1; + } + + return 0; +out1: + platform_driver_unregister(&exynos5_busfreq_int_driver); +out: + return ret; +} +late_initcall(exynos5_busfreq_int_init); + +static void __exit exynos5_busfreq_int_exit(void) +{ + platform_device_unregister(exynos5_devfreq_pdev); + platform_driver_unregister(&exynos5_busfreq_int_driver); +} +module_exit(exynos5_busfreq_int_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("EXYNOS5 busfreq driver with devfreq framework"); |