Author: tuexen
Date: Thu Apr 27 17:53:05 2017
New Revision: 317512
URL: https://svnweb.freebsd.org/changeset/base/317512
Log:
armv8 has support for optional CRC32C instructions. This patch checks if they are
available and if that is true make use of them.
Thank you very much to Andrew Turner for providing help and review the patch!
Reviewed by: andrew
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D10499
Added:
head/sys/libkern/arm64/
head/sys/libkern/arm64/crc32c_armv8.S (contents, props changed)
Modified:
head/sys/conf/files.arm64
head/sys/libkern/crc32.c
head/sys/sys/libkern.h
head/tests/sys/kern/Makefile
head/tests/sys/kern/libkern_crc32.c
Modified: head/sys/conf/files.arm64
==============================================================================
--- head/sys/conf/files.arm64 Thu Apr 27 16:38:28 2017 (r317511)
+++ head/sys/conf/files.arm64 Thu Apr 27 17:53:05 2017 (r317512)
@@ -191,6 +191,7 @@ libkern/fls.c standard
libkern/flsl.c standard
libkern/flsll.c standard
libkern/memset.c standard
+libkern/arm64/crc32c_armv8.S standard
cddl/contrib/opensolaris/common/atomic/aarch64/opensolaris_atomic.S optional zfs | dtrace compile-with "${CDDL_C}"
cddl/dev/dtrace/aarch64/dtrace_asm.S optional dtrace compile-with "${DTRACE_S}"
cddl/dev/dtrace/aarch64/dtrace_subr.c optional dtrace compile-with "${DTRACE_C}"
Added: head/sys/libkern/arm64/crc32c_armv8.S
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/sys/libkern/arm64/crc32c_armv8.S Thu Apr 27 17:53:05 2017 (r317512)
@@ -0,0 +1,78 @@
+/*-
+ * Copyright (c) 2017 Michael Tuexen
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include <machine/asm.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * uint32_t
+ * armv8_crc32c(uint32_t crc, const unsigned char *buf, unsigned int len)
+ */
+
+ENTRY(armv8_crc32c)
+ cbz w2, end
+ tbz x1, #0x0, half_word_aligned
+ sub w2, w2, 0x1
+ ldr w10, [x1], #0x1
+ crc32cb w0, w0, w10
+half_word_aligned:
+ cmp w2, #0x2
+ b.lo last_byte
+ tbz x1, #0x1, word_aligned
+ sub w2, w2, 0x2
+ ldr w10, [x1], #0x2
+ crc32ch w0, w0, w10
+word_aligned:
+ cmp w2, #0x4
+ b.lo last_half_word
+ tbz x1, #0x2, double_word_aligned
+ sub w2, w2, 0x4
+ ldr w10, [x1], #0x4
+ crc32cw w0, w0, w10
+double_word_aligned:
+ lsr w9, w2, #0x3
+ cbz w9, last_word
+loop:
+ ldr x10, [x1], #0x8
+ crc32cx w0, w0, x10
+ subs w9, w9, #1
+ b.ne loop
+last_word:
+ tbz w2, #0x2, last_half_word
+ ldr w10, [x1], #0x4
+ crc32cw w0, w0, w10
+last_half_word:
+ tbz w2, #0x1, last_byte
+ ldr w10, [x1], #0x2
+ crc32ch w0, w0, w10
+last_byte:
+ tbz w2, #0x0, end
+ ldr w10, [x1], #0x1
+ crc32cb w0, w0, w10
+end:
+ ret
+END(armv8_crc32c)
Modified: head/sys/libkern/crc32.c
==============================================================================
--- head/sys/libkern/crc32.c Thu Apr 27 16:38:28 2017 (r317511)
+++ head/sys/libkern/crc32.c Thu Apr 27 17:53:05 2017 (r317512)
@@ -54,6 +54,10 @@ __FBSDID("$FreeBSD$");
#include <machine/specialreg.h>
#endif
+#if defined(__aarch64__)
+#include <machine/cpu.h>
+#endif
+
const uint32_t crc32_tab[] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
@@ -760,6 +764,18 @@ calculate_crc32c(uint32_t crc32c,
return (sse42_crc32c(crc32c, buffer, length));
} else
#endif
+#if defined(__aarch64__)
+ uint64_t reg;
+
+ /*
+ * We only test for CRC32 support on the CPU with index 0 assuming that
+ * this applies to all CPUs.
+ */
+ reg = READ_SPECIALREG(id_aa64isar0_el1);
+ if (ID_AA64ISAR0_CRC32(reg) != ID_AA64ISAR0_CRC32_NONE) {
+ return (armv8_crc32c(crc32c, buffer, length));
+ } else
+#endif
if (length < 4) {
return (singletable_crc32c(crc32c, buffer, length));
} else {
Modified: head/sys/sys/libkern.h
==============================================================================
--- head/sys/sys/libkern.h Thu Apr 27 16:38:28 2017 (r317511)
+++ head/sys/sys/libkern.h Thu Apr 27 17:53:05 2017 (r317512)
@@ -210,6 +210,9 @@ calculate_crc32c(uint32_t crc32c, const
#if defined(__amd64__) || defined(__i386__)
uint32_t sse42_crc32c(uint32_t, const unsigned char *, unsigned);
#endif
+#if defined(__aarch64__)
+uint32_t armv8_crc32c(uint32_t, const unsigned char *, unsigned int);
+#endif
#endif
Modified: head/tests/sys/kern/Makefile
==============================================================================
--- head/tests/sys/kern/Makefile Thu Apr 27 16:38:28 2017 (r317511)
+++ head/tests/sys/kern/Makefile Thu Apr 27 17:53:05 2017 (r317512)
@@ -30,10 +30,16 @@ NETBSD_ATF_TESTS_C+= mqueue_test
CFLAGS.mqueue_test+= -I${SRCTOP}/tests
LIBADD.mqueue_test+= rt
-.if ${MACHINE_ARCH} == "amd64" || ${MACHINE_ARCH} == "i386"
+.if ${MACHINE_ARCH} == "amd64" || \
+ ${MACHINE_ARCH} == "i386" || \
+ ${MACHINE_ARCH} == "aarch64"
ATF_TESTS_C+= libkern_crc32
CFLAGS.libkern_crc32+= -DUSERSPACE_TESTING
+.if ${MACHINE_ARCH} == "amd64" || ${MACHINE_ARCH} == "i386"
LDADD.libkern_crc32+= ${SRCTOP}/sys/libkern/x86/crc32_sse42.c
+.else
+LDADD.libkern_crc32+= ${SRCTOP}/sys/libkern/arm64/crc32c_armv8.S
+.endif
.endif
# subr_unit.c contains functions whose prototypes lie in headers that cannot be
Modified: head/tests/sys/kern/libkern_crc32.c
==============================================================================
--- head/tests/sys/kern/libkern_crc32.c Thu Apr 27 16:38:28 2017 (r317511)
+++ head/tests/sys/kern/libkern_crc32.c Thu Apr 27 17:53:05 2017 (r317512)
@@ -32,7 +32,13 @@
#include <atf-c.h>
+#if defined(__amd64__) || defined(__i386__)
extern uint32_t sse42_crc32c(uint32_t, const unsigned char *, unsigned);
+#elif defined(__aarch64__)
+extern uint32_t armv8_crc32c(uint32_t, const unsigned char *, unsigned);
+#else
+#error These tests are not supported on this platform
+#endif
ATF_TC_WITHOUT_HEAD(crc32c_basic_correctness);
ATF_TC_BODY(crc32c_basic_correctness, tc)
@@ -79,8 +85,13 @@ ATF_TC_BODY(crc32c_basic_correctness, tc
ATF_REQUIRE(nitems(inputs) == nitems(results));
for (i = 0; i < nitems(inputs); i++) {
+#if defined(__amd64__) || defined(__i386__)
act = sse42_crc32c(~0, (const void *)&inputs[i],
sizeof(inputs[0]));
+#else
+ act = armv8_crc32c(~0, (const void *)&inputs[i],
+ sizeof(inputs[0]));
+#endif
ATF_REQUIRE_MSG(act == results[i],
"crc32c(0x%jx) = 0x%08x, got 0x%08x", (uintmax_t)inputs[i],
results[i], act);
@@ -100,7 +111,11 @@ ATF_TC_BODY(crc32c_alignment, tc)
for (i = 1; i < 8; i++) {
memcpy(&buf[i], &input, sizeof(input));
+#if defined(__amd64__) || defined(__i386__)
act = sse42_crc32c(~0, (const void *)&buf[i], sizeof(input));
+#else
+ act = armv8_crc32c(~0, (const void *)&buf[i], sizeof(input));
+#endif
ATF_REQUIRE_MSG(act == result,
"crc32c(0x%jx) = 0x%08x, got 0x%08x", (uintmax_t)input,
result, act);
@@ -117,7 +132,11 @@ ATF_TC_BODY(crc32c_trailing_bytes, tc)
const uint32_t result = 0xec638d62;
uint32_t act;
+#if defined(__amd64__) || defined(__i386__)
act = sse42_crc32c(~0, input, sizeof(input));
+#else
+ act = armv8_crc32c(~0, input, sizeof(input));
+#endif
ATF_REQUIRE_MSG(act == result, "expected 0x%08x, got 0x%08x", result,
act);
}