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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-05 13:51:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-05 13:51:19 -0700
commitdfc25e4503aef6b82a1de4a0fbe19aafa8648fbe (patch)
tree0a4f3a07e2286918298e635186e42726f4658cbd /drivers/clocksource/qcom-timer.c
parent9f800363bb0ea459e15bef0928a72c88d374e489 (diff)
parent8f881c67368f82d0e20e1072b50b21132cc2440d (diff)
downloadop-kernel-dev-dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe.zip
op-kernel-dev-dfc25e4503aef6b82a1de4a0fbe19aafa8648fbe.tar.gz
Merge tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Arnd Bergmann: "These cleanup patches are mainly move stuff around and should all be harmless. They are mainly split out so that other branches can be based on top to avoid conflicts. Notable changes are: - We finally remove all mach/timex.h, after CLOCK_TICK_RATE is no longer used (Uwe Kleine-König) - The Qualcomm MSM platform is split out into legacy mach-msm and new-style mach-qcom, to allow easier maintainance of the new hardware support without regressions (Kumar Gala) - A rework of some of the Kconfig logic to simplify multiplatform support (Rob Herring) - Samsung Exynos gets closer to supporting multiplatform (Sachin Kamat and others) - mach-bcm3528 gets merged into mach-bcm (Stephen Warren) - at91 gains some common clock framework support (Alexandre Belloni, Jean-Jacques Hiblot and other French people)" * tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (89 commits) ARM: hisi: select HAVE_ARM_SCU only for SMP ARM: efm32: allow uncompress debug output ARM: prima2: build reset code standalone ARM: at91: add PWM clock ARM: at91: move sam9261 SoC to common clk ARM: at91: prepare common clk transition for sam9261 SoC ARM: at91: updated the at91_dt_defconfig with support for the ADS7846 ARM: at91: dt: sam9261: Device Tree support for the at91sam9261ek ARM: at91: dt: defconfig: Added the sam9261 to the list of DT-enabled SOCs ARM: at91: dt: Add at91sam9261 dt SoC support ARM: at91: switch sam9rl to common clock framework ARM: at91/dt: define main clk frequency of at91sam9rlek ARM: at91/dt: define at91sam9rl clocks ARM: at91: prepare common clk transition for sam9rl SoCs ARM: at91: prepare sam9 dt boards transition to common clk ARM: at91: dt: sam9rl: Device Tree for the at91sam9rlek ARM: at91/defconfig: Add the sam9rl to the list of DT-enabled SOCs ARM: at91: Add at91sam9rl DT SoC support ARM: at91: prepare at91sam9rl DT transition ARM: at91/defconfig: refresh at91sam9260_9g20_defconfig ...
Diffstat (limited to 'drivers/clocksource/qcom-timer.c')
-rw-r--r--drivers/clocksource/qcom-timer.c330
1 files changed, 330 insertions, 0 deletions
diff --git a/drivers/clocksource/qcom-timer.c b/drivers/clocksource/qcom-timer.c
new file mode 100644
index 0000000..e807acf
--- /dev/null
+++ b/drivers/clocksource/qcom-timer.c
@@ -0,0 +1,330 @@
+/*
+ *
+ * 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>
+
+#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
+
+#define MSM_DGT_SHIFT 5
+
+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 (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+ 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 void msm_timer_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ u32 ctrl;
+
+ ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+ ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_RESUME:
+ case CLOCK_EVT_MODE_PERIODIC:
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ /* Timer is enabled in set_next_event */
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ break;
+ }
+ writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+}
+
+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;
+
+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_mode = msm_timer_set_mode;
+ 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_mode(CLOCK_EVT_MODE_UNUSED, evt);
+ disable_percpu_irq(evt->irq);
+}
+
+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;
+}
+
+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 void __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(__this_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);
+}
+
+#ifdef CONFIG_ARCH_QCOM
+static void __init msm_dt_timer_init(struct device_node *np)
+{
+ u32 freq;
+ int irq;
+ 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;
+ }
+
+ /* 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;
+ }
+
+ /* We use CPU0's DGT for the clocksource */
+ if (of_property_read_u32(np, "cpu-offset", &percpu_offset))
+ percpu_offset = 0;
+
+ if (of_address_to_resource(np, 0, &res)) {
+ pr_err("Failed to parse DGT resource\n");
+ return;
+ }
+
+ cpu0_base = ioremap(res.start + percpu_offset, resource_size(&res));
+ if (!cpu0_base) {
+ pr_err("Failed to map source base\n");
+ return;
+ }
+
+ if (of_property_read_u32(np, "clock-frequency", &freq)) {
+ pr_err("Unknown frequency\n");
+ return;
+ }
+
+ 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);
+
+ 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);
+#else
+
+static int __init msm_timer_map(phys_addr_t addr, u32 event, u32 source,
+ u32 sts)
+{
+ void __iomem *base;
+
+ base = ioremap(addr, SZ_256);
+ if (!base) {
+ pr_err("Failed to map timer base\n");
+ return -ENOMEM;
+ }
+ event_base = base + event;
+ source_base = base + source;
+ if (sts)
+ sts_base = base + sts;
+
+ return 0;
+}
+
+static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs)
+{
+ /*
+ * Shift timer count down by a constant due to unreliable lower bits
+ * on some targets.
+ */
+ return msm_read_timer_count(cs) >> MSM_DGT_SHIFT;
+}
+
+void __init msm7x01_timer_init(void)
+{
+ struct clocksource *cs = &msm_clocksource;
+
+ if (msm_timer_map(0xc0100000, 0x0, 0x10, 0x0))
+ return;
+ cs->read = msm_read_timer_count_shift;
+ cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT));
+ /* 600 KHz */
+ msm_timer_init(19200000 >> MSM_DGT_SHIFT, 32 - MSM_DGT_SHIFT, 7,
+ false);
+}
+
+void __init msm7x30_timer_init(void)
+{
+ if (msm_timer_map(0xc0100000, 0x4, 0x24, 0x80))
+ return;
+ msm_timer_init(24576000 / 4, 32, 1, false);
+}
+
+void __init qsd8x50_timer_init(void)
+{
+ if (msm_timer_map(0xAC100000, 0x0, 0x10, 0x34))
+ return;
+ msm_timer_init(19200000 / 4, 32, 7, false);
+}
+#endif
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