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authorLinus Torvalds <torvalds@linux-foundation.org>2013-07-03 14:35:40 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-07-03 14:35:40 -0700
commitf991fae5c6d42dfc5029150b05a78cf3f6c18cc9 (patch)
treed140deb437bde0631778b4984eeb72c1f4ee0c1d /drivers/cpufreq/pasemi-cpufreq.c
parentd4141531f63a29bb2a980092b6f2828c385e6edd (diff)
parent2c843bd92ec276ecb68504b3b5ffa7066183f032 (diff)
downloadop-kernel-dev-f991fae5c6d42dfc5029150b05a78cf3f6c18cc9.zip
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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/pasemi-cpufreq.c')
-rw-r--r--drivers/cpufreq/pasemi-cpufreq.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/cpufreq/pasemi-cpufreq.c b/drivers/cpufreq/pasemi-cpufreq.c
new file mode 100644
index 0000000..b704da4
--- /dev/null
+++ b/drivers/cpufreq/pasemi-cpufreq.c
@@ -0,0 +1,331 @@
+/*
+ * Copyright (C) 2007 PA Semi, Inc
+ *
+ * Authors: Egor Martovetsky <egor@pasemi.com>
+ * Olof Johansson <olof@lixom.net>
+ *
+ * Maintained by: Olof Johansson <olof@lixom.net>
+ *
+ * Based on arch/powerpc/platforms/cell/cbe_cpufreq.c:
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/cpufreq.h>
+#include <linux/timer.h>
+#include <linux/module.h>
+
+#include <asm/hw_irq.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/time.h>
+#include <asm/smp.h>
+
+#define SDCASR_REG 0x0100
+#define SDCASR_REG_STRIDE 0x1000
+#define SDCPWR_CFGA0_REG 0x0100
+#define SDCPWR_PWST0_REG 0x0000
+#define SDCPWR_GIZTIME_REG 0x0440
+
+/* SDCPWR_GIZTIME_REG fields */
+#define SDCPWR_GIZTIME_GR 0x80000000
+#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff
+
+/* Offset of ASR registers from SDC base */
+#define SDCASR_OFFSET 0x120000
+
+static void __iomem *sdcpwr_mapbase;
+static void __iomem *sdcasr_mapbase;
+
+static DEFINE_MUTEX(pas_switch_mutex);
+
+/* Current astate, is used when waking up from power savings on
+ * one core, in case the other core has switched states during
+ * the idle time.
+ */
+static int current_astate;
+
+/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */
+static struct cpufreq_frequency_table pas_freqs[] = {
+ {0, 0},
+ {1, 0},
+ {2, 0},
+ {3, 0},
+ {4, 0},
+ {0, CPUFREQ_TABLE_END},
+};
+
+static struct freq_attr *pas_cpu_freqs_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+/*
+ * hardware specific functions
+ */
+
+static int get_astate_freq(int astate)
+{
+ u32 ret;
+ ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10));
+
+ return ret & 0x3f;
+}
+
+static int get_cur_astate(int cpu)
+{
+ u32 ret;
+
+ ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG);
+ ret = (ret >> (cpu * 4)) & 0x7;
+
+ return ret;
+}
+
+static int get_gizmo_latency(void)
+{
+ u32 giztime, ret;
+
+ giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG);
+
+ /* just provide the upper bound */
+ if (giztime & SDCPWR_GIZTIME_GR)
+ ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000;
+ else
+ ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000;
+
+ return ret;
+}
+
+static void set_astate(int cpu, unsigned int astate)
+{
+ unsigned long flags;
+
+ /* Return if called before init has run */
+ if (unlikely(!sdcasr_mapbase))
+ return;
+
+ local_irq_save(flags);
+
+ out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate);
+
+ local_irq_restore(flags);
+}
+
+int check_astate(void)
+{
+ return get_cur_astate(hard_smp_processor_id());
+}
+
+void restore_astate(int cpu)
+{
+ set_astate(cpu, current_astate);
+}
+
+/*
+ * cpufreq functions
+ */
+
+static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ const u32 *max_freqp;
+ u32 max_freq;
+ int i, cur_astate;
+ struct resource res;
+ struct device_node *cpu, *dn;
+ int err = -ENODEV;
+
+ cpu = of_get_cpu_node(policy->cpu, NULL);
+
+ if (!cpu)
+ goto out;
+
+ dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
+ if (!dn)
+ dn = of_find_compatible_node(NULL, NULL,
+ "pasemi,pwrficient-sdc");
+ if (!dn)
+ goto out;
+ err = of_address_to_resource(dn, 0, &res);
+ of_node_put(dn);
+ if (err)
+ goto out;
+ sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000);
+ if (!sdcasr_mapbase) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo");
+ if (!dn)
+ dn = of_find_compatible_node(NULL, NULL,
+ "pasemi,pwrficient-gizmo");
+ if (!dn) {
+ err = -ENODEV;
+ goto out_unmap_sdcasr;
+ }
+ err = of_address_to_resource(dn, 0, &res);
+ of_node_put(dn);
+ if (err)
+ goto out_unmap_sdcasr;
+ sdcpwr_mapbase = ioremap(res.start, 0x1000);
+ if (!sdcpwr_mapbase) {
+ err = -EINVAL;
+ goto out_unmap_sdcasr;
+ }
+
+ pr_debug("init cpufreq on CPU %d\n", policy->cpu);
+
+ max_freqp = of_get_property(cpu, "clock-frequency", NULL);
+ if (!max_freqp) {
+ err = -EINVAL;
+ goto out_unmap_sdcpwr;
+ }
+
+ /* we need the freq in kHz */
+ max_freq = *max_freqp / 1000;
+
+ pr_debug("max clock-frequency is at %u kHz\n", max_freq);
+ pr_debug("initializing frequency table\n");
+
+ /* initialize frequency table */
+ for (i=0; pas_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) {
+ pas_freqs[i].frequency =
+ get_astate_freq(pas_freqs[i].driver_data) * 100000;
+ pr_debug("%d: %d\n", i, pas_freqs[i].frequency);
+ }
+
+ policy->cpuinfo.transition_latency = get_gizmo_latency();
+
+ cur_astate = get_cur_astate(policy->cpu);
+ pr_debug("current astate is at %d\n",cur_astate);
+
+ policy->cur = pas_freqs[cur_astate].frequency;
+ cpumask_copy(policy->cpus, cpu_online_mask);
+
+ ppc_proc_freq = policy->cur * 1000ul;
+
+ cpufreq_frequency_table_get_attr(pas_freqs, policy->cpu);
+
+ /* this ensures that policy->cpuinfo_min and policy->cpuinfo_max
+ * are set correctly
+ */
+ return cpufreq_frequency_table_cpuinfo(policy, pas_freqs);
+
+out_unmap_sdcpwr:
+ iounmap(sdcpwr_mapbase);
+
+out_unmap_sdcasr:
+ iounmap(sdcasr_mapbase);
+out:
+ return err;
+}
+
+static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
+{
+ /*
+ * We don't support CPU hotplug. Don't unmap after the system
+ * has already made it to a running state.
+ */
+ if (system_state != SYSTEM_BOOTING)
+ return 0;
+
+ if (sdcasr_mapbase)
+ iounmap(sdcasr_mapbase);
+ if (sdcpwr_mapbase)
+ iounmap(sdcpwr_mapbase);
+
+ cpufreq_frequency_table_put_attr(policy->cpu);
+ return 0;
+}
+
+static int pas_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, pas_freqs);
+}
+
+static int pas_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ struct cpufreq_freqs freqs;
+ int pas_astate_new;
+ int i;
+
+ cpufreq_frequency_table_target(policy,
+ pas_freqs,
+ target_freq,
+ relation,
+ &pas_astate_new);
+
+ freqs.old = policy->cur;
+ freqs.new = pas_freqs[pas_astate_new].frequency;
+
+ mutex_lock(&pas_switch_mutex);
+ cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
+
+ pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n",
+ policy->cpu,
+ pas_freqs[pas_astate_new].frequency,
+ pas_freqs[pas_astate_new].driver_data);
+
+ current_astate = pas_astate_new;
+
+ for_each_online_cpu(i)
+ set_astate(i, pas_astate_new);
+
+ cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
+ mutex_unlock(&pas_switch_mutex);
+
+ ppc_proc_freq = freqs.new * 1000ul;
+ return 0;
+}
+
+static struct cpufreq_driver pas_cpufreq_driver = {
+ .name = "pas-cpufreq",
+ .owner = THIS_MODULE,
+ .flags = CPUFREQ_CONST_LOOPS,
+ .init = pas_cpufreq_cpu_init,
+ .exit = pas_cpufreq_cpu_exit,
+ .verify = pas_cpufreq_verify,
+ .target = pas_cpufreq_target,
+ .attr = pas_cpu_freqs_attr,
+};
+
+/*
+ * module init and destoy
+ */
+
+static int __init pas_cpufreq_init(void)
+{
+ if (!of_machine_is_compatible("PA6T-1682M") &&
+ !of_machine_is_compatible("pasemi,pwrficient"))
+ return -ENODEV;
+
+ return cpufreq_register_driver(&pas_cpufreq_driver);
+}
+
+static void __exit pas_cpufreq_exit(void)
+{
+ cpufreq_unregister_driver(&pas_cpufreq_driver);
+}
+
+module_init(pas_cpufreq_init);
+module_exit(pas_cpufreq_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>");
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