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-rw-r--r--arch/arm64/lib/Makefile2
-rw-r--r--arch/arm64/lib/delay.c23
-rw-r--r--arch/arm64/lib/tishift.S80
3 files changed, 100 insertions, 5 deletions
diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
index 9a8cb96555d6..4e696f96451f 100644
--- a/arch/arm64/lib/Makefile
+++ b/arch/arm64/lib/Makefile
@@ -3,7 +3,7 @@ lib-y := bitops.o clear_user.o delay.o copy_from_user.o \
copy_to_user.o copy_in_user.o copy_page.o \
clear_page.o memchr.o memcpy.o memmove.o memset.o \
memcmp.o strcmp.o strncmp.o strlen.o strnlen.o \
- strchr.o strrchr.o
+ strchr.o strrchr.o tishift.o
# Tell the compiler to treat all general purpose registers (with the
# exception of the IP registers, which are already handled by the caller
diff --git a/arch/arm64/lib/delay.c b/arch/arm64/lib/delay.c
index dad4ec9bbfd1..e48ac402e7be 100644
--- a/arch/arm64/lib/delay.c
+++ b/arch/arm64/lib/delay.c
@@ -24,10 +24,28 @@
#include <linux/module.h>
#include <linux/timex.h>
+#include <clocksource/arm_arch_timer.h>
+
+#define USECS_TO_CYCLES(time_usecs) \
+ xloops_to_cycles((time_usecs) * 0x10C7UL)
+
+static inline unsigned long xloops_to_cycles(unsigned long xloops)
+{
+ return (xloops * loops_per_jiffy * HZ) >> 32;
+}
+
void __delay(unsigned long cycles)
{
cycles_t start = get_cycles();
+ if (arch_timer_evtstrm_available()) {
+ const cycles_t timer_evt_period =
+ USECS_TO_CYCLES(ARCH_TIMER_EVT_STREAM_PERIOD_US);
+
+ while ((get_cycles() - start + timer_evt_period) < cycles)
+ wfe();
+ }
+
while ((get_cycles() - start) < cycles)
cpu_relax();
}
@@ -35,10 +53,7 @@ EXPORT_SYMBOL(__delay);
inline void __const_udelay(unsigned long xloops)
{
- unsigned long loops;
-
- loops = xloops * loops_per_jiffy * HZ;
- __delay(loops >> 32);
+ __delay(xloops_to_cycles(xloops));
}
EXPORT_SYMBOL(__const_udelay);
diff --git a/arch/arm64/lib/tishift.S b/arch/arm64/lib/tishift.S
new file mode 100644
index 000000000000..0179a43cc045
--- /dev/null
+++ b/arch/arm64/lib/tishift.S
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+
+ENTRY(__ashlti3)
+ cbz x2, 1f
+ mov x3, #64
+ sub x3, x3, x2
+ cmp x3, #0
+ b.le 2f
+ lsl x1, x1, x2
+ lsr x3, x0, x3
+ lsl x2, x0, x2
+ orr x1, x1, x3
+ mov x0, x2
+1:
+ ret
+2:
+ neg w1, w3
+ mov x2, #0
+ lsl x1, x0, x1
+ mov x0, x2
+ ret
+ENDPROC(__ashlti3)
+
+ENTRY(__ashrti3)
+ cbz x2, 3f
+ mov x3, #64
+ sub x3, x3, x2
+ cmp x3, #0
+ b.le 4f
+ lsr x0, x0, x2
+ lsl x3, x1, x3
+ asr x2, x1, x2
+ orr x0, x0, x3
+ mov x1, x2
+3:
+ ret
+4:
+ neg w0, w3
+ asr x2, x1, #63
+ asr x0, x1, x0
+ mov x1, x2
+ ret
+ENDPROC(__ashrti3)
+
+ENTRY(__lshrti3)
+ cbz x2, 1f
+ mov x3, #64
+ sub x3, x3, x2
+ cmp x3, #0
+ b.le 2f
+ lsr x0, x0, x2
+ lsl x3, x1, x3
+ lsr x2, x1, x2
+ orr x0, x0, x3
+ mov x1, x2
+1:
+ ret
+2:
+ neg w0, w3
+ mov x2, #0
+ lsr x0, x1, x0
+ mov x1, x2
+ ret
+ENDPROC(__lshrti3)