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/cpufreq/ppc-corenet-cpufreq.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/cpufreq/ppc-corenet-cpufreq.c')
-rw-r--r-- | drivers/cpufreq/ppc-corenet-cpufreq.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/ppc-corenet-cpufreq.c new file mode 100644 index 0000000..3cae452 --- /dev/null +++ b/drivers/cpufreq/ppc-corenet-cpufreq.c @@ -0,0 +1,380 @@ +/* + * Copyright 2013 Freescale Semiconductor, Inc. + * + * CPU Frequency Scaling driver for Freescale PowerPC corenet SoCs. + * + * 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. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/clk.h> +#include <linux/cpufreq.h> +#include <linux/errno.h> +#include <sysdev/fsl_soc.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/smp.h> + +/** + * struct cpu_data - per CPU data struct + * @clk: the clk of CPU + * @parent: the parent node of cpu clock + * @table: frequency table + */ +struct cpu_data { + struct clk *clk; + struct device_node *parent; + struct cpufreq_frequency_table *table; +}; + +/** + * struct soc_data - SoC specific data + * @freq_mask: mask the disallowed frequencies + * @flag: unique flags + */ +struct soc_data { + u32 freq_mask[4]; + u32 flag; +}; + +#define FREQ_MASK 1 +/* see hardware specification for the allowed frqeuencies */ +static const struct soc_data sdata[] = { + { /* used by p2041 and p3041 */ + .freq_mask = {0x8, 0x8, 0x2, 0x2}, + .flag = FREQ_MASK, + }, + { /* used by p5020 */ + .freq_mask = {0x8, 0x2}, + .flag = FREQ_MASK, + }, + { /* used by p4080, p5040 */ + .freq_mask = {0}, + .flag = 0, + }, +}; + +/* + * the minimum allowed core frequency, in Hz + * for chassis v1.0, >= platform frequency + * for chassis v2.0, >= platform frequency / 2 + */ +static u32 min_cpufreq; +static const u32 *fmask; + +/* serialize frequency changes */ +static DEFINE_MUTEX(cpufreq_lock); +static DEFINE_PER_CPU(struct cpu_data *, cpu_data); + +/* cpumask in a cluster */ +static DEFINE_PER_CPU(cpumask_var_t, cpu_mask); + +#ifndef CONFIG_SMP +static inline const struct cpumask *cpu_core_mask(int cpu) +{ + return cpumask_of(0); +} +#endif + +static unsigned int corenet_cpufreq_get_speed(unsigned int cpu) +{ + struct cpu_data *data = per_cpu(cpu_data, cpu); + + return clk_get_rate(data->clk) / 1000; +} + +/* reduce the duplicated frequencies in frequency table */ +static void freq_table_redup(struct cpufreq_frequency_table *freq_table, + int count) +{ + int i, j; + + for (i = 1; i < count; i++) { + for (j = 0; j < i; j++) { + if (freq_table[j].frequency == CPUFREQ_ENTRY_INVALID || + freq_table[j].frequency != + freq_table[i].frequency) + continue; + + freq_table[i].frequency = CPUFREQ_ENTRY_INVALID; + break; + } + } +} + +/* sort the frequencies in frequency table in descenting order */ +static void freq_table_sort(struct cpufreq_frequency_table *freq_table, + int count) +{ + int i, j, ind; + unsigned int freq, max_freq; + struct cpufreq_frequency_table table; + for (i = 0; i < count - 1; i++) { + max_freq = freq_table[i].frequency; + ind = i; + for (j = i + 1; j < count; j++) { + freq = freq_table[j].frequency; + if (freq == CPUFREQ_ENTRY_INVALID || + freq <= max_freq) + continue; + ind = j; + max_freq = freq; + } + + if (ind != i) { + /* exchange the frequencies */ + table.driver_data = freq_table[i].driver_data; + table.frequency = freq_table[i].frequency; + freq_table[i].driver_data = freq_table[ind].driver_data; + freq_table[i].frequency = freq_table[ind].frequency; + freq_table[ind].driver_data = table.driver_data; + freq_table[ind].frequency = table.frequency; + } + } +} + +static int corenet_cpufreq_cpu_init(struct cpufreq_policy *policy) +{ + struct device_node *np; + int i, count, ret; + u32 freq, mask; + struct clk *clk; + struct cpufreq_frequency_table *table; + struct cpu_data *data; + unsigned int cpu = policy->cpu; + + np = of_get_cpu_node(cpu, NULL); + if (!np) + return -ENODEV; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) { + pr_err("%s: no memory\n", __func__); + goto err_np; + } + + data->clk = of_clk_get(np, 0); + if (IS_ERR(data->clk)) { + pr_err("%s: no clock information\n", __func__); + goto err_nomem2; + } + + data->parent = of_parse_phandle(np, "clocks", 0); + if (!data->parent) { + pr_err("%s: could not get clock information\n", __func__); + goto err_nomem2; + } + + count = of_property_count_strings(data->parent, "clock-names"); + table = kcalloc(count + 1, sizeof(*table), GFP_KERNEL); + if (!table) { + pr_err("%s: no memory\n", __func__); + goto err_node; + } + + if (fmask) + mask = fmask[get_hard_smp_processor_id(cpu)]; + else + mask = 0x0; + + for (i = 0; i < count; i++) { + clk = of_clk_get(data->parent, i); + freq = clk_get_rate(clk); + /* + * the clock is valid if its frequency is not masked + * and large than minimum allowed frequency. + */ + if (freq < min_cpufreq || (mask & (1 << i))) + table[i].frequency = CPUFREQ_ENTRY_INVALID; + else + table[i].frequency = freq / 1000; + table[i].driver_data = i; + } + freq_table_redup(table, count); + freq_table_sort(table, count); + table[i].frequency = CPUFREQ_TABLE_END; + + /* set the min and max frequency properly */ + ret = cpufreq_frequency_table_cpuinfo(policy, table); + if (ret) { + pr_err("invalid frequency table: %d\n", ret); + goto err_nomem1; + } + + data->table = table; + per_cpu(cpu_data, cpu) = data; + + /* update ->cpus if we have cluster, no harm if not */ + cpumask_copy(policy->cpus, per_cpu(cpu_mask, cpu)); + for_each_cpu(i, per_cpu(cpu_mask, cpu)) + per_cpu(cpu_data, i) = data; + + policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + policy->cur = corenet_cpufreq_get_speed(policy->cpu); + + cpufreq_frequency_table_get_attr(table, cpu); + of_node_put(np); + + return 0; + +err_nomem1: + kfree(table); +err_node: + of_node_put(data->parent); +err_nomem2: + per_cpu(cpu_data, cpu) = NULL; + kfree(data); +err_np: + of_node_put(np); + + return -ENODEV; +} + +static int __exit corenet_cpufreq_cpu_exit(struct cpufreq_policy *policy) +{ + struct cpu_data *data = per_cpu(cpu_data, policy->cpu); + unsigned int cpu; + + cpufreq_frequency_table_put_attr(policy->cpu); + of_node_put(data->parent); + kfree(data->table); + kfree(data); + + for_each_cpu(cpu, per_cpu(cpu_mask, policy->cpu)) + per_cpu(cpu_data, cpu) = NULL; + + return 0; +} + +static int corenet_cpufreq_verify(struct cpufreq_policy *policy) +{ + struct cpufreq_frequency_table *table = + per_cpu(cpu_data, policy->cpu)->table; + + return cpufreq_frequency_table_verify(policy, table); +} + +static int corenet_cpufreq_target(struct cpufreq_policy *policy, + unsigned int target_freq, unsigned int relation) +{ + struct cpufreq_freqs freqs; + unsigned int new; + struct clk *parent; + int ret; + struct cpu_data *data = per_cpu(cpu_data, policy->cpu); + + cpufreq_frequency_table_target(policy, data->table, + target_freq, relation, &new); + + if (policy->cur == data->table[new].frequency) + return 0; + + freqs.old = policy->cur; + freqs.new = data->table[new].frequency; + + mutex_lock(&cpufreq_lock); + cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); + + parent = of_clk_get(data->parent, data->table[new].driver_data); + ret = clk_set_parent(data->clk, parent); + if (ret) + freqs.new = freqs.old; + + cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); + mutex_unlock(&cpufreq_lock); + + return ret; +} + +static struct freq_attr *corenet_cpufreq_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + NULL, +}; + +static struct cpufreq_driver ppc_corenet_cpufreq_driver = { + .name = "ppc_cpufreq", + .owner = THIS_MODULE, + .flags = CPUFREQ_CONST_LOOPS, + .init = corenet_cpufreq_cpu_init, + .exit = __exit_p(corenet_cpufreq_cpu_exit), + .verify = corenet_cpufreq_verify, + .target = corenet_cpufreq_target, + .get = corenet_cpufreq_get_speed, + .attr = corenet_cpufreq_attr, +}; + +static const struct of_device_id node_matches[] __initdata = { + { .compatible = "fsl,p2041-clockgen", .data = &sdata[0], }, + { .compatible = "fsl,p3041-clockgen", .data = &sdata[0], }, + { .compatible = "fsl,p5020-clockgen", .data = &sdata[1], }, + { .compatible = "fsl,p4080-clockgen", .data = &sdata[2], }, + { .compatible = "fsl,p5040-clockgen", .data = &sdata[2], }, + { .compatible = "fsl,qoriq-clockgen-2.0", }, + {} +}; + +static int __init ppc_corenet_cpufreq_init(void) +{ + int ret; + struct device_node *np; + const struct of_device_id *match; + const struct soc_data *data; + unsigned int cpu; + + np = of_find_matching_node(NULL, node_matches); + if (!np) + return -ENODEV; + + for_each_possible_cpu(cpu) { + if (!alloc_cpumask_var(&per_cpu(cpu_mask, cpu), GFP_KERNEL)) + goto err_mask; + cpumask_copy(per_cpu(cpu_mask, cpu), cpu_core_mask(cpu)); + } + + match = of_match_node(node_matches, np); + data = match->data; + if (data) { + if (data->flag) + fmask = data->freq_mask; + min_cpufreq = fsl_get_sys_freq(); + } else { + min_cpufreq = fsl_get_sys_freq() / 2; + } + + of_node_put(np); + + ret = cpufreq_register_driver(&ppc_corenet_cpufreq_driver); + if (!ret) + pr_info("Freescale PowerPC corenet CPU frequency scaling driver\n"); + + return ret; + +err_mask: + for_each_possible_cpu(cpu) + free_cpumask_var(per_cpu(cpu_mask, cpu)); + + return -ENOMEM; +} +module_init(ppc_corenet_cpufreq_init); + +static void __exit ppc_corenet_cpufreq_exit(void) +{ + unsigned int cpu; + + for_each_possible_cpu(cpu) + free_cpumask_var(per_cpu(cpu_mask, cpu)); + + cpufreq_unregister_driver(&ppc_corenet_cpufreq_driver); +} +module_exit(ppc_corenet_cpufreq_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Tang Yuantian <Yuantian.Tang@freescale.com>"); +MODULE_DESCRIPTION("cpufreq driver for Freescale e500mc series SoCs"); |