Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 283 insertions, 0 deletions

diff --git a/arch/mips/vdso/gettimeofday.c b/arch/mips/vdso/gettimeofday.c
new file mode 100644
index 000000000..9fdc84fc3
--- /dev/null
+++ b/arch/mips/vdso/gettimeofday.c
@@ -0,0 +1,283 @@
+/*
+ * Copyright (C) 2015 Imagination Technologies
+ * Author: Alex Smith <alex.smith@imgtec.com>
+ *
+ * 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 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include "vdso.h"
+
+#include <linux/compiler.h>
+#include <linux/time.h>
+
+#include <asm/clocksource.h>
+#include <asm/io.h>
+#include <asm/unistd.h>
+#include <asm/vdso.h>
+
+#if MIPS_ISA_REV < 6
+#define VDSO_SYSCALL_CLOBBERS "hi", "lo",
+#else
+#define VDSO_SYSCALL_CLOBBERS
+#endif
+
+#ifdef CONFIG_MIPS_CLOCK_VSYSCALL
+
+static __always_inline long gettimeofday_fallback(struct timeval *_tv,
+					  struct timezone *_tz)
+{
+	register struct timezone *tz asm("a1") = _tz;
+	register struct timeval *tv asm("a0") = _tv;
+	register long ret asm("v0");
+	register long nr asm("v0") = __NR_gettimeofday;
+	register long error asm("a3");
+
+	asm volatile(
+	"       syscall\n"
+	: "=r" (ret), "=r" (error)
+	: "r" (tv), "r" (tz), "r" (nr)
+	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
+	  "$14", "$15", "$24", "$25",
+	  VDSO_SYSCALL_CLOBBERS
+	  "memory");
+
+	return error ? -ret : ret;
+}
+
+#endif
+
+static __always_inline long clock_gettime_fallback(clockid_t _clkid,
+					   struct timespec *_ts)
+{
+	register struct timespec *ts asm("a1") = _ts;
+	register clockid_t clkid asm("a0") = _clkid;
+	register long ret asm("v0");
+	register long nr asm("v0") = __NR_clock_gettime;
+	register long error asm("a3");
+
+	asm volatile(
+	"       syscall\n"
+	: "=r" (ret), "=r" (error)
+	: "r" (clkid), "r" (ts), "r" (nr)
+	: "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13",
+	  "$14", "$15", "$24", "$25",
+	  VDSO_SYSCALL_CLOBBERS
+	  "memory");
+
+	return error ? -ret : ret;
+}
+
+static __always_inline int do_realtime_coarse(struct timespec *ts,
+					      const union mips_vdso_data *data)
+{
+	u32 start_seq;
+
+	do {
+		start_seq = vdso_data_read_begin(data);
+
+		ts->tv_sec = data->xtime_sec;
+		ts->tv_nsec = data->xtime_nsec >> data->cs_shift;
+	} while (vdso_data_read_retry(data, start_seq));
+
+	return 0;
+}
+
+static __always_inline int do_monotonic_coarse(struct timespec *ts,
+					       const union mips_vdso_data *data)
+{
+	u32 start_seq;
+	u64 to_mono_sec;
+	u64 to_mono_nsec;
+
+	do {
+		start_seq = vdso_data_read_begin(data);
+
+		ts->tv_sec = data->xtime_sec;
+		ts->tv_nsec = data->xtime_nsec >> data->cs_shift;
+
+		to_mono_sec = data->wall_to_mono_sec;
+		to_mono_nsec = data->wall_to_mono_nsec;
+	} while (vdso_data_read_retry(data, start_seq));
+
+	ts->tv_sec += to_mono_sec;
+	timespec_add_ns(ts, to_mono_nsec);
+
+	return 0;
+}
+
+#ifdef CONFIG_CSRC_R4K
+
+static __always_inline u64 read_r4k_count(void)
+{
+	unsigned int count;
+
+	__asm__ __volatile__(
+	"	.set push\n"
+	"	.set mips32r2\n"
+	"	rdhwr	%0, $2\n"
+	"	.set pop\n"
+	: "=r" (count));
+
+	return count;
+}
+
+#endif
+
+#ifdef CONFIG_CLKSRC_MIPS_GIC
+
+static __always_inline u64 read_gic_count(const union mips_vdso_data *data)
+{
+	void __iomem *gic = get_gic(data);
+	u32 hi, hi2, lo;
+
+	do {
+		hi = __raw_readl(gic + sizeof(lo));
+		lo = __raw_readl(gic);
+		hi2 = __raw_readl(gic + sizeof(lo));
+	} while (hi2 != hi);
+
+	return (((u64)hi) << 32) + lo;
+}
+
+#endif
+
+static __always_inline u64 get_ns(const union mips_vdso_data *data)
+{
+	u64 cycle_now, delta, nsec;
+
+	switch (data->clock_mode) {
+#ifdef CONFIG_CSRC_R4K
+	case VDSO_CLOCK_R4K:
+		cycle_now = read_r4k_count();
+		break;
+#endif
+#ifdef CONFIG_CLKSRC_MIPS_GIC
+	case VDSO_CLOCK_GIC:
+		cycle_now = read_gic_count(data);
+		break;
+#endif
+	default:
+		return 0;
+	}
+
+	delta = (cycle_now - data->cs_cycle_last) & data->cs_mask;
+
+	nsec = (delta * data->cs_mult) + data->xtime_nsec;
+	nsec >>= data->cs_shift;
+
+	return nsec;
+}
+
+static __always_inline int do_realtime(struct timespec *ts,
+				       const union mips_vdso_data *data)
+{
+	u32 start_seq;
+	u64 ns;
+
+	do {
+		start_seq = vdso_data_read_begin(data);
+
+		if (data->clock_mode == VDSO_CLOCK_NONE)
+			return -ENOSYS;
+
+		ts->tv_sec = data->xtime_sec;
+		ns = get_ns(data);
+	} while (vdso_data_read_retry(data, start_seq));
+
+	ts->tv_nsec = 0;
+	timespec_add_ns(ts, ns);
+
+	return 0;
+}
+
+static __always_inline int do_monotonic(struct timespec *ts,
+					const union mips_vdso_data *data)
+{
+	u32 start_seq;
+	u64 ns;
+	u64 to_mono_sec;
+	u64 to_mono_nsec;
+
+	do {
+		start_seq = vdso_data_read_begin(data);
+
+		if (data->clock_mode == VDSO_CLOCK_NONE)
+			return -ENOSYS;
+
+		ts->tv_sec = data->xtime_sec;
+		ns = get_ns(data);
+
+		to_mono_sec = data->wall_to_mono_sec;
+		to_mono_nsec = data->wall_to_mono_nsec;
+	} while (vdso_data_read_retry(data, start_seq));
+
+	ts->tv_sec += to_mono_sec;
+	ts->tv_nsec = 0;
+	timespec_add_ns(ts, ns + to_mono_nsec);
+
+	return 0;
+}
+
+#ifdef CONFIG_MIPS_CLOCK_VSYSCALL
+
+/*
+ * This is behind the ifdef so that we don't provide the symbol when there's no
+ * possibility of there being a usable clocksource, because there's nothing we
+ * can do without it. When libc fails the symbol lookup it should fall back on
+ * the standard syscall path.
+ */
+int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+	const union mips_vdso_data *data = get_vdso_data();
+	struct timespec ts;
+	int ret;
+
+	ret = do_realtime(&ts, data);
+	if (ret)
+		return gettimeofday_fallback(tv, tz);
+
+	if (tv) {
+		tv->tv_sec = ts.tv_sec;
+		tv->tv_usec = ts.tv_nsec / 1000;
+	}
+
+	if (tz) {
+		tz->tz_minuteswest = data->tz_minuteswest;
+		tz->tz_dsttime = data->tz_dsttime;
+	}
+
+	return 0;
+}
+
+#endif /* CONFIG_MIPS_CLOCK_VSYSCALL */
+
+int __vdso_clock_gettime(clockid_t clkid, struct timespec *ts)
+{
+	const union mips_vdso_data *data = get_vdso_data();
+	int ret = -1;
+
+	switch (clkid) {
+	case CLOCK_REALTIME_COARSE:
+		ret = do_realtime_coarse(ts, data);
+		break;
+	case CLOCK_MONOTONIC_COARSE:
+		ret = do_monotonic_coarse(ts, data);
+		break;
+	case CLOCK_REALTIME:
+		ret = do_realtime(ts, data);
+		break;
+	case CLOCK_MONOTONIC:
+		ret = do_monotonic(ts, data);
+		break;
+	default:
+		break;
+	}
+
+	if (ret)
+		ret = clock_gettime_fallback(clkid, ts);
+
+	return ret;
+}