linux/drivers/clocksource/qcom-timer.c

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/*
*
* Copyright (C) 2007 Google, Inc.
* Copyright (c) 2009-2012,2014, The Linux Foundation. All rights reserved.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*
*/
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#include <asm/delay.h>
#define TIMER_MATCH_VAL 0x0000
#define TIMER_COUNT_VAL 0x0004
#define TIMER_ENABLE 0x0008
#define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1)
#define TIMER_ENABLE_EN BIT(0)
#define TIMER_CLEAR 0x000C
#define DGT_CLK_CTL 0x10
#define DGT_CLK_CTL_DIV_4 0x3
#define TIMER_STS_GPT0_CLR_PEND BIT(10)
#define GPT_HZ 32768
static void __iomem *event_base;
static void __iomem *sts_base;
static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = dev_id;
/* Stop the timer tick */
if (clockevent_state_oneshot(evt)) {
u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~TIMER_ENABLE_EN;
writel_relaxed(ctrl, event_base + TIMER_ENABLE);
}
evt->event_handler(evt);
return IRQ_HANDLED;
}
static int msm_timer_set_next_event(unsigned long cycles,
struct clock_event_device *evt)
{
u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~TIMER_ENABLE_EN;
writel_relaxed(ctrl, event_base + TIMER_ENABLE);
writel_relaxed(ctrl, event_base + TIMER_CLEAR);
writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
if (sts_base)
while (readl_relaxed(sts_base) & TIMER_STS_GPT0_CLR_PEND)
cpu_relax();
writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
return 0;
}
static int msm_timer_shutdown(struct clock_event_device *evt)
{
u32 ctrl;
ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
writel_relaxed(ctrl, event_base + TIMER_ENABLE);
return 0;
}
static struct clock_event_device __percpu *msm_evt;
static void __iomem *source_base;
static notrace cycle_t msm_read_timer_count(struct clocksource *cs)
{
return readl_relaxed(source_base + TIMER_COUNT_VAL);
}
static struct clocksource msm_clocksource = {
.name = "dg_timer",
.rating = 300,
.read = msm_read_timer_count,
.mask = CLOCKSOURCE_MASK(32),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static int msm_timer_irq;
static int msm_timer_has_ppi;
arm: delete __cpuinit/__CPUINIT usage from all ARM users The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-17 19:43:14 +00:00
static int msm_local_timer_setup(struct clock_event_device *evt)
{
int cpu = smp_processor_id();
int err;
evt->irq = msm_timer_irq;
evt->name = "msm_timer";
evt->features = CLOCK_EVT_FEAT_ONESHOT;
evt->rating = 200;
evt->set_state_shutdown = msm_timer_shutdown;
evt->set_state_oneshot = msm_timer_shutdown;
evt->tick_resume = msm_timer_shutdown;
evt->set_next_event = msm_timer_set_next_event;
evt->cpumask = cpumask_of(cpu);
clockevents_config_and_register(evt, GPT_HZ, 4, 0xffffffff);
if (msm_timer_has_ppi) {
enable_percpu_irq(evt->irq, IRQ_TYPE_EDGE_RISING);
} else {
err = request_irq(evt->irq, msm_timer_interrupt,
IRQF_TIMER | IRQF_NOBALANCING |
IRQF_TRIGGER_RISING, "gp_timer", evt);
if (err)
pr_err("request_irq failed\n");
}
return 0;
}
static void msm_local_timer_stop(struct clock_event_device *evt)
{
evt->set_state_shutdown(evt);
disable_percpu_irq(evt->irq);
}
Now that we have a generic arch hook for broadcast we can remove the local timer API entirely. Doing so will reduce code in ARM core, reduce the architecture dependencies of our timer drivers, and simplify the code because we no longer go through an architecture layer that is essentially a hotplug notifier. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIcBAABCAAGBQJRydGwAAoJENidgRMleOc9tMMP/Awy0ETkLHQkXdFdRNLQH7Jd BpDagzBkpt/U/qsh2Dy5Yhz7Qf/HQg6CwJK/b1apHguSPzNcSov+YS7ArPV+kuDY 9OCF5wkVqPW7BPHlxJ+2QAjayIFUaBR+35kpiU+hv9Gkhs11oK90iAWxEIDUGzA6 5miuOVJeyDEwV8des3NYmVVOKziHLJjX3fjMVnc2gxE6PLmOEUQ9t42bVU1aCfub pRMUXNuG+aFk8lRExPfs4wWfEKCOHrgJPSE4OPFp3pDJeqhFi5tXTiPBQ22FpNf5 78fEDeguS0QS6f/3rGKSdGu/Yz5Lmcldv4tOkfzvNaZP7zhE18wKJu6bSCrZ/Onn MnhriYWZh+YgX1V8wTMFMPEV+OR+FJdN4C8PhvNWmMC1Xoq25HtrVQUP5aElgAJs mLcgTXxLYpvZH3jPxdtMR9IuDc+86qmFerGShWqp/1YaNHwpR8dNZxFyVNfw+FUL /GoAjk/6MsJlZUchiF7I8yp4jYyMcXcV8Bi4tgIAf5rJO9PZBpuxtyAL9uVHnL13 pwkctMnMQwoP6AE9uYfbdnHCKJxF1hny4tKI5sNxAmK8I6bBkfibIZ3sNRAbSrY7 56kV+tJrrgvgAUDkgdluyS9eFs26iHGPsHK4lmzJzFylWmvWFa8tWpP6G0kCa0wP A1XCqUOryLeL8enPV+z2 =wZbm -----END PGP SIGNATURE----- Merge tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm into next/cleanup From Stephen Boyd: Now that we have a generic arch hook for broadcast we can remove the local timer API entirely. Doing so will reduce code in ARM core, reduce the architecture dependencies of our timer drivers, and simplify the code because we no longer go through an architecture layer that is essentially a hotplug notifier. * tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm: ARM: smp: Remove local timer API clocksource: time-armada-370-xp: Divorce from local timer API clocksource: time-armada-370-xp: Fix sparse warning ARM: msm: Divorce msm_timer from local timer API ARM: PRIMA2: Divorce timer-marco from local timer API ARM: EXYNOS4: Divorce mct from local timer API ARM: OMAP2+: Divorce from local timer API ARM: smp_twd: Divorce smp_twd from local timer API ARM: smp: Remove duplicate dummy timer implementation Resolved a large number of conflicts due to __cpuinit cleanups, etc. Signed-off-by: Olof Johansson <olof@lixom.net>
2013-07-23 21:51:34 +00:00
static int msm_timer_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
/*
* Grab cpu pointer in each case to avoid spurious
* preemptible warnings
*/
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_STARTING:
msm_local_timer_setup(this_cpu_ptr(msm_evt));
break;
case CPU_DYING:
msm_local_timer_stop(this_cpu_ptr(msm_evt));
break;
}
return NOTIFY_OK;
}
Now that we have a generic arch hook for broadcast we can remove the local timer API entirely. Doing so will reduce code in ARM core, reduce the architecture dependencies of our timer drivers, and simplify the code because we no longer go through an architecture layer that is essentially a hotplug notifier. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIcBAABCAAGBQJRydGwAAoJENidgRMleOc9tMMP/Awy0ETkLHQkXdFdRNLQH7Jd BpDagzBkpt/U/qsh2Dy5Yhz7Qf/HQg6CwJK/b1apHguSPzNcSov+YS7ArPV+kuDY 9OCF5wkVqPW7BPHlxJ+2QAjayIFUaBR+35kpiU+hv9Gkhs11oK90iAWxEIDUGzA6 5miuOVJeyDEwV8des3NYmVVOKziHLJjX3fjMVnc2gxE6PLmOEUQ9t42bVU1aCfub pRMUXNuG+aFk8lRExPfs4wWfEKCOHrgJPSE4OPFp3pDJeqhFi5tXTiPBQ22FpNf5 78fEDeguS0QS6f/3rGKSdGu/Yz5Lmcldv4tOkfzvNaZP7zhE18wKJu6bSCrZ/Onn MnhriYWZh+YgX1V8wTMFMPEV+OR+FJdN4C8PhvNWmMC1Xoq25HtrVQUP5aElgAJs mLcgTXxLYpvZH3jPxdtMR9IuDc+86qmFerGShWqp/1YaNHwpR8dNZxFyVNfw+FUL /GoAjk/6MsJlZUchiF7I8yp4jYyMcXcV8Bi4tgIAf5rJO9PZBpuxtyAL9uVHnL13 pwkctMnMQwoP6AE9uYfbdnHCKJxF1hny4tKI5sNxAmK8I6bBkfibIZ3sNRAbSrY7 56kV+tJrrgvgAUDkgdluyS9eFs26iHGPsHK4lmzJzFylWmvWFa8tWpP6G0kCa0wP A1XCqUOryLeL8enPV+z2 =wZbm -----END PGP SIGNATURE----- Merge tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm into next/cleanup From Stephen Boyd: Now that we have a generic arch hook for broadcast we can remove the local timer API entirely. Doing so will reduce code in ARM core, reduce the architecture dependencies of our timer drivers, and simplify the code because we no longer go through an architecture layer that is essentially a hotplug notifier. * tag 'remove-local-timers' of git://git.kernel.org/pub/scm/linux/kernel/git/davidb/linux-msm: ARM: smp: Remove local timer API clocksource: time-armada-370-xp: Divorce from local timer API clocksource: time-armada-370-xp: Fix sparse warning ARM: msm: Divorce msm_timer from local timer API ARM: PRIMA2: Divorce timer-marco from local timer API ARM: EXYNOS4: Divorce mct from local timer API ARM: OMAP2+: Divorce from local timer API ARM: smp_twd: Divorce smp_twd from local timer API ARM: smp: Remove duplicate dummy timer implementation Resolved a large number of conflicts due to __cpuinit cleanups, etc. Signed-off-by: Olof Johansson <olof@lixom.net>
2013-07-23 21:51:34 +00:00
static struct notifier_block msm_timer_cpu_nb = {
.notifier_call = msm_timer_cpu_notify,
};
static u64 notrace msm_sched_clock_read(void)
{
return msm_clocksource.read(&msm_clocksource);
}
static unsigned long msm_read_current_timer(void)
{
return msm_clocksource.read(&msm_clocksource);
}
static struct delay_timer msm_delay_timer = {
.read_current_timer = msm_read_current_timer,
};
static int __init msm_timer_init(u32 dgt_hz, int sched_bits, int irq,
bool percpu)
{
struct clocksource *cs = &msm_clocksource;
int res = 0;
msm_timer_irq = irq;
msm_timer_has_ppi = percpu;
msm_evt = alloc_percpu(struct clock_event_device);
if (!msm_evt) {
pr_err("memory allocation failed for clockevents\n");
goto err;
}
if (percpu)
res = request_percpu_irq(irq, msm_timer_interrupt,
"gp_timer", msm_evt);
if (res) {
pr_err("request_percpu_irq failed\n");
} else {
res = register_cpu_notifier(&msm_timer_cpu_nb);
if (res) {
free_percpu_irq(irq, msm_evt);
goto err;
}
/* Immediately configure the timer on the boot CPU */
msm_local_timer_setup(raw_cpu_ptr(msm_evt));
}
err:
writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
res = clocksource_register_hz(cs, dgt_hz);
if (res)
pr_err("clocksource_register failed\n");
sched_clock_register(msm_sched_clock_read, sched_bits, dgt_hz);
msm_delay_timer.freq = dgt_hz;
register_current_timer_delay(&msm_delay_timer);
return res;
}
static int __init msm_dt_timer_init(struct device_node *np)
{
u32 freq;
int irq, ret;
struct resource res;
u32 percpu_offset;
void __iomem *base;
void __iomem *cpu0_base;
base = of_iomap(np, 0);
if (!base) {
pr_err("Failed to map event base\n");
return -ENXIO;
}
/* We use GPT0 for the clockevent */
irq = irq_of_parse_and_map(np, 1);
if (irq <= 0) {
pr_err("Can't get irq\n");
return -EINVAL;
}
/* We use CPU0's DGT for the clocksource */
if (of_property_read_u32(np, "cpu-offset", &percpu_offset))
percpu_offset = 0;
ret = of_address_to_resource(np, 0, &res);
if (ret) {
pr_err("Failed to parse DGT resource\n");
return ret;
}
cpu0_base = ioremap(res.start + percpu_offset, resource_size(&res));
if (!cpu0_base) {
pr_err("Failed to map source base\n");
return -EINVAL;
}
if (of_property_read_u32(np, "clock-frequency", &freq)) {
pr_err("Unknown frequency\n");
return -EINVAL;
}
event_base = base + 0x4;
sts_base = base + 0x88;
source_base = cpu0_base + 0x24;
freq /= 4;
writel_relaxed(DGT_CLK_CTL_DIV_4, source_base + DGT_CLK_CTL);
return msm_timer_init(freq, 32, irq, !!percpu_offset);
}
CLOCKSOURCE_OF_DECLARE(kpss_timer, "qcom,kpss-timer", msm_dt_timer_init);
CLOCKSOURCE_OF_DECLARE(scss_timer, "qcom,scss-timer", msm_dt_timer_init);