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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/kernel/time.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/time.c')
-rw-r--r--arch/x86/kernel/time.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
new file mode 100644
index 000000000..e42faa792
--- /dev/null
+++ b/arch/x86/kernel/time.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 1991,1992,1995 Linus Torvalds
+ * Copyright (c) 1994 Alan Modra
+ * Copyright (c) 1995 Markus Kuhn
+ * Copyright (c) 1996 Ingo Molnar
+ * Copyright (c) 1998 Andrea Arcangeli
+ * Copyright (c) 2002,2006 Vojtech Pavlik
+ * Copyright (c) 2003 Andi Kleen
+ *
+ */
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/i8253.h>
+#include <linux/time.h>
+#include <linux/export.h>
+
+#include <asm/vsyscall.h>
+#include <asm/x86_init.h>
+#include <asm/i8259.h>
+#include <asm/timer.h>
+#include <asm/hpet.h>
+#include <asm/time.h>
+
+unsigned long profile_pc(struct pt_regs *regs)
+{
+ unsigned long pc = instruction_pointer(regs);
+
+ if (!user_mode(regs) && in_lock_functions(pc)) {
+#ifdef CONFIG_FRAME_POINTER
+ return *(unsigned long *)(regs->bp + sizeof(long));
+#else
+ unsigned long *sp = (unsigned long *)regs->sp;
+ /*
+ * Return address is either directly at stack pointer
+ * or above a saved flags. Eflags has bits 22-31 zero,
+ * kernel addresses don't.
+ */
+ if (sp[0] >> 22)
+ return sp[0];
+ if (sp[1] >> 22)
+ return sp[1];
+#endif
+ }
+ return pc;
+}
+EXPORT_SYMBOL(profile_pc);
+
+/*
+ * Default timer interrupt handler for PIT/HPET
+ */
+static irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+ global_clock_event->event_handler(global_clock_event);
+ return IRQ_HANDLED;
+}
+
+static void __init setup_default_timer_irq(void)
+{
+ unsigned long flags = IRQF_NOBALANCING | IRQF_IRQPOLL | IRQF_TIMER;
+
+ /*
+ * Unconditionally register the legacy timer interrupt; even
+ * without legacy PIC/PIT we need this for the HPET0 in legacy
+ * replacement mode.
+ */
+ if (request_irq(0, timer_interrupt, flags, "timer", NULL))
+ pr_info("Failed to register legacy timer interrupt\n");
+}
+
+/* Default timer init function */
+void __init hpet_time_init(void)
+{
+ if (!hpet_enable()) {
+ if (!pit_timer_init())
+ return;
+ }
+
+ setup_default_timer_irq();
+}
+
+static __init void x86_late_time_init(void)
+{
+ /*
+ * Before PIT/HPET init, select the interrupt mode. This is required
+ * to make the decision whether PIT should be initialized correct.
+ */
+ x86_init.irqs.intr_mode_select();
+
+ /* Setup the legacy timers */
+ x86_init.timers.timer_init();
+
+ /*
+ * After PIT/HPET timers init, set up the final interrupt mode for
+ * delivering IRQs.
+ */
+ x86_init.irqs.intr_mode_init();
+ tsc_init();
+
+ if (static_cpu_has(X86_FEATURE_WAITPKG))
+ use_tpause_delay();
+}
+
+/*
+ * Initialize TSC and delay the periodic timer init to
+ * late x86_late_time_init() so ioremap works.
+ */
+void __init time_init(void)
+{
+ late_time_init = x86_late_time_init;
+}
+
+/*
+ * Sanity check the vdso related archdata content.
+ */
+void clocksource_arch_init(struct clocksource *cs)
+{
+ if (cs->vdso_clock_mode == VDSO_CLOCKMODE_NONE)
+ return;
+
+ if (cs->mask != CLOCKSOURCE_MASK(64)) {
+ pr_warn("clocksource %s registered with invalid mask %016llx for VDSO. Disabling VDSO support.\n",
+ cs->name, cs->mask);
+ cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE;
+ }
+}