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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-11 17:56:37 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-11 17:56:37 -0800
commitc0222ac086669a631814bbf857f8c8023452a4d7 (patch)
treebb1d9908031fcf69016eeefa7b35a4f68f414333 /drivers/clocksource
parent140cd7fb04a4a2bc09a30980bc8104cc89e09330 (diff)
parente2965cd0003f222bd49f67907c2bc6ed691c6d20 (diff)
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle: "This is an unusually large pull request for MIPS - in parts because lots of patches missed the 3.18 deadline but primarily because some folks opened the flood gates. - Retire the MIPS-specific phys_t with the generic phys_addr_t. - Improvments for the backtrace code used by oprofile. - Better backtraces on SMP systems. - Cleanups for the Octeon platform code. - Cleanups and fixes for the Loongson platform code. - Cleanups and fixes to the firmware library. - Switch ATH79 platform to use the firmware library. - Grand overhault to the SEAD3 and Malta interrupt code. - Move the GIC interrupt code to drivers/irqchip - Lots of GIC cleanups and updates to the GIC code to use modern IRQ infrastructures and features of the kernel. - OF documentation updates for the GIC bindings - Move GIC clocksource driver to drivers/clocksource - Merge GIC clocksource driver with clockevent driver. - Further updates to bring the GIC clocksource driver up to date. - R3000 TLB code cleanups - Improvments to the Loongson 3 platform code. - Convert pr_warning to pr_warn. - Merge a bunch of small lantiq and ralink fixes that have been staged/lingering inside the openwrt tree for a while. - Update archhelp for IP22/IP32 - Fix a number of issues for Loongson 1B. - New clocksource and clockevent driver for Loongson 1B. - Further work on clk handling for Loongson 1B. - Platform work for Broadcom BMIPS. - Error handling cleanups for TurboChannel. - Fixes and optimization to the microMIPS support. - Option to disable the FTLB. - Dump more relevant information on machine check exception - Change binfmt to allow arch to examine PT_*PROC headers - Support for new style FPU register model in O32 - VDSO randomization. - BCM47xx cleanups - BCM47xx reimplement the way the kernel accesses NVRAM information. - Random cleanups - Add support for ATH25 platforms - Remove pointless locking code in some PCI platforms. - Some improvments to EVA support - Minor Alchemy cleanup" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (185 commits) MIPS: Add MFHC0 and MTHC0 instructions to uasm. MIPS: Cosmetic cleanups of page table headers. MIPS: Add CP0 macros for extended EntryLo registers MIPS: Remove now unused definition of phys_t. MIPS: Replace use of phys_t with phys_addr_t. MIPS: Replace MIPS-specific 64BIT_PHYS_ADDR with generic PHYS_ADDR_T_64BIT PCMCIA: Alchemy Don't select 64BIT_PHYS_ADDR in Kconfig. MIPS: lib: memset: Clean up some MIPS{EL,EB} ifdefery MIPS: iomap: Use __mem_{read,write}{b,w,l} for MMIO MIPS: <asm/types.h> fix indentation. MAINTAINERS: Add entry for BMIPS multiplatform kernel MIPS: Enable VDSO randomization MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration MIPS: Remove declaration of obsolete arch_init_clk_ops() MIPS: atomic.h: Reformat to fit in 79 columns MIPS: Apply `.insn' to fixup labels throughout MIPS: Fix microMIPS LL/SC immediate offsets MIPS: Kconfig: Only allow 32-bit microMIPS builds MIPS: signal.c: Fix an invalid cast in ISA mode bit handling MIPS: mm: Only build one microassembler that is suitable ...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/Kconfig5
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/mips-gic-timer.c166
3 files changed, 172 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index f657a48d20eb..fc01ec27d3c8 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -224,4 +224,9 @@ config CLKSRC_VERSATILE
ARM Versatile, RealView and Versatile Express reference
platforms.
+config CLKSRC_MIPS_GIC
+ bool
+ depends on MIPS_GIC
+ select CLKSRC_OF
+
endmenu
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index fae0435cc23d..94d90b24b56b 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -47,3 +47,4 @@ obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST) += dummy_timer.o
obj-$(CONFIG_ARCH_KEYSTONE) += timer-keystone.o
obj-$(CONFIG_ARCH_INTEGRATOR_AP) += timer-integrator-ap.o
obj-$(CONFIG_CLKSRC_VERSATILE) += versatile.o
+obj-$(CONFIG_CLKSRC_MIPS_GIC) += mips-gic-timer.o
diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c
new file mode 100644
index 000000000000..3bd31b1321f6
--- /dev/null
+++ b/drivers/clocksource/mips-gic-timer.c
@@ -0,0 +1,166 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
+ */
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irqchip/mips-gic.h>
+#include <linux/notifier.h>
+#include <linux/of_irq.h>
+#include <linux/percpu.h>
+#include <linux/smp.h>
+#include <linux/time.h>
+
+static DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device);
+static int gic_timer_irq;
+static unsigned int gic_frequency;
+
+static int gic_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+ u64 cnt;
+ int res;
+
+ cnt = gic_read_count();
+ cnt += (u64)delta;
+ gic_write_cpu_compare(cnt, cpumask_first(evt->cpumask));
+ res = ((int)(gic_read_count() - cnt) >= 0) ? -ETIME : 0;
+ return res;
+}
+
+static void gic_set_clock_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ /* Nothing to do ... */
+}
+
+static irqreturn_t gic_compare_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *cd = dev_id;
+
+ gic_write_compare(gic_read_compare());
+ cd->event_handler(cd);
+ return IRQ_HANDLED;
+}
+
+struct irqaction gic_compare_irqaction = {
+ .handler = gic_compare_interrupt,
+ .percpu_dev_id = &gic_clockevent_device,
+ .flags = IRQF_PERCPU | IRQF_TIMER,
+ .name = "timer",
+};
+
+static void gic_clockevent_cpu_init(struct clock_event_device *cd)
+{
+ unsigned int cpu = smp_processor_id();
+
+ cd->name = "MIPS GIC";
+ cd->features = CLOCK_EVT_FEAT_ONESHOT |
+ CLOCK_EVT_FEAT_C3STOP;
+
+ cd->rating = 350;
+ cd->irq = gic_timer_irq;
+ cd->cpumask = cpumask_of(cpu);
+ cd->set_next_event = gic_next_event;
+ cd->set_mode = gic_set_clock_mode;
+
+ clockevents_config_and_register(cd, gic_frequency, 0x300, 0x7fffffff);
+
+ enable_percpu_irq(gic_timer_irq, IRQ_TYPE_NONE);
+}
+
+static void gic_clockevent_cpu_exit(struct clock_event_device *cd)
+{
+ disable_percpu_irq(gic_timer_irq);
+}
+
+static int gic_cpu_notifier(struct notifier_block *nb, unsigned long action,
+ void *data)
+{
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_STARTING:
+ gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device));
+ break;
+ case CPU_DYING:
+ gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device));
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block gic_cpu_nb = {
+ .notifier_call = gic_cpu_notifier,
+};
+
+static int gic_clockevent_init(void)
+{
+ if (!cpu_has_counter || !gic_frequency)
+ return -ENXIO;
+
+ setup_percpu_irq(gic_timer_irq, &gic_compare_irqaction);
+
+ register_cpu_notifier(&gic_cpu_nb);
+
+ gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device));
+
+ return 0;
+}
+
+static cycle_t gic_hpt_read(struct clocksource *cs)
+{
+ return gic_read_count();
+}
+
+static struct clocksource gic_clocksource = {
+ .name = "GIC",
+ .read = gic_hpt_read,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init __gic_clocksource_init(void)
+{
+ /* Set clocksource mask. */
+ gic_clocksource.mask = CLOCKSOURCE_MASK(gic_get_count_width());
+
+ /* Calculate a somewhat reasonable rating value. */
+ gic_clocksource.rating = 200 + gic_frequency / 10000000;
+
+ clocksource_register_hz(&gic_clocksource, gic_frequency);
+
+ gic_clockevent_init();
+}
+
+void __init gic_clocksource_init(unsigned int frequency)
+{
+ gic_frequency = frequency;
+ gic_timer_irq = MIPS_GIC_IRQ_BASE +
+ GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_COMPARE);
+
+ __gic_clocksource_init();
+}
+
+static void __init gic_clocksource_of_init(struct device_node *node)
+{
+ if (WARN_ON(!gic_present || !node->parent ||
+ !of_device_is_compatible(node->parent, "mti,gic")))
+ return;
+
+ if (of_property_read_u32(node, "clock-frequency", &gic_frequency)) {
+ pr_err("GIC frequency not specified.\n");
+ return;
+ }
+ gic_timer_irq = irq_of_parse_and_map(node, 0);
+ if (!gic_timer_irq) {
+ pr_err("GIC timer IRQ not specified.\n");
+ return;
+ }
+
+ __gic_clocksource_init();
+}
+CLOCKSOURCE_OF_DECLARE(mips_gic_timer, "mti,gic-timer",
+ gic_clocksource_of_init);