Add support for AArch32 CRC32 and CRC32C instructions added in ARMv8
and add a CPU feature flag to enable these instructions.
The CRC32-C implementation used is the built-in qemu implementation
and The CRC-32 implementation is from zlib. This requires adding zlib
to LIBS to ensure it is linked for the linux-user binary.
Signed-off-by: Will Newton <will.new...@linaro.org>
---
configure | 2 +-
target-arm/cpu.c | 1 +
target-arm/cpu.h | 1 +
target-arm/helper.c | 39 +++++++++++++++++++++++++++++++++++
target-arm/helper.h | 3 +++
target-arm/translate.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 101 insertions(+), 1 deletion(-)
Changes in v4:
- Add feature flag for CRC instructions
- Check for SBZ bits in ARM encoding
- Use more accurate flags for the helper definition
diff --git a/configure b/configure
index 423f435..030da86 100755
--- a/configure
+++ b/configure
@@ -1657,7 +1657,7 @@ EOF
"Make sure to have the zlib libs and headers installed."
fi
fi
-libs_softmmu="$libs_softmmu -lz"
+LIBS="$LIBS -lz"
##########################################
# libseccomp check
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 6e7ce89..8231e57 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -922,6 +922,7 @@ static void arm_any_initfn(Object *obj)
set_feature(&cpu->env, ARM_FEATURE_THUMB2EE);
set_feature(&cpu->env, ARM_FEATURE_ARM_DIV);
set_feature(&cpu->env, ARM_FEATURE_V7MP);
+ set_feature(&cpu->env, ARM_FEATURE_CRC);
#ifdef TARGET_AARCH64
set_feature(&cpu->env, ARM_FEATURE_AARCH64);
#endif
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index 3c8a2db..c3aeb74 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -615,6 +615,7 @@ enum arm_features {
ARM_FEATURE_AARCH64, /* supports 64 bit mode */
ARM_FEATURE_V8_AES, /* implements AES part of v8 Crypto Extensions */
ARM_FEATURE_CBAR, /* has cp15 CBAR */
+ ARM_FEATURE_CRC, /* ARMv8 CRC instructions */
};
static inline int arm_feature(CPUARMState *env, int feature)
diff --git a/target-arm/helper.c b/target-arm/helper.c
index 1b111b6..5e4f0fa 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -5,6 +5,8 @@
#include "sysemu/arch_init.h"
#include "sysemu/sysemu.h"
#include "qemu/bitops.h"
+#include "qemu/crc32c.h"
+#include <zlib.h> /* For crc32 */
#ifndef CONFIG_USER_ONLY
static inline int get_phys_addr(CPUARMState *env, uint32_t address,
@@ -4392,3 +4394,40 @@ int arm_rmode_to_sf(int rmode)
}
return rmode;
}
+
+static void crc_init_buffer(uint8_t *buf, uint32_t val, uint32_t bytes)
+{
+ memset(buf, 0, 4);
+
+ if (bytes == 1) {
+ buf[0] = val & 0xff;
+ } else if (bytes == 2) {
+ buf[0] = val & 0xff;
+ buf[1] = (val >> 8) & 0xff;
+ } else {
+ buf[0] = val & 0xff;
+ buf[1] = (val >> 8) & 0xff;
+ buf[2] = (val >> 16) & 0xff;
+ buf[3] = (val >> 24) & 0xff;
+ }
+}
+
+uint32_t HELPER(crc32)(uint32_t acc, uint32_t val, uint32_t bytes)
+{
+ uint8_t buf[4];
+
+ crc_init_buffer(buf, val, bytes);
+
+ /* zlib crc32 converts the accumulator and output to one's complement. */
+ return crc32(acc ^ 0xffffffff, buf, bytes) ^ 0xffffffff;
+}
+
+uint32_t HELPER(crc32c)(uint32_t acc, uint32_t val, uint32_t bytes)
+{
+ uint8_t buf[4];
+
+ crc_init_buffer(buf, val, bytes);
+
+ /* Linux crc32c converts the output to one's complement. */
+ return crc32c(acc, buf, bytes) ^ 0xffffffff;
+}
diff --git a/target-arm/helper.h b/target-arm/helper.h
index 19bd620..9738e49 100644
--- a/target-arm/helper.h
+++ b/target-arm/helper.h
@@ -497,6 +497,9 @@ DEF_HELPER_3(neon_qzip32, void, env, i32, i32)
DEF_HELPER_4(crypto_aese, void, env, i32, i32, i32)
DEF_HELPER_4(crypto_aesmc, void, env, i32, i32, i32)
+DEF_HELPER_FLAGS_3(crc32, TCG_CALL_NO_RWG_SE, i32, i32, i32, i32)
+DEF_HELPER_FLAGS_3(crc32c, TCG_CALL_NO_RWG_SE, i32, i32, i32, i32)
+
#ifdef TARGET_AARCH64
#include "helper-a64.h"
#endif
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 6ccf0ba..253d2a1 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -7561,6 +7561,36 @@ static void disas_arm_insn(CPUARMState * env,
DisasContext *s)
store_reg(s, 14, tmp2);
gen_bx(s, tmp);
break;
+ case 0x4:
+ {
+ /* crc32/crc32c */
+ uint32_t c = extract32(insn, 8, 4);
+
+ /* Check this CPU supports ARMv8 CRC instructions.
+ * op1 == 3 is UNPREDICTABLE but handle as UNDEFINED.
+ * Bits 8, 10 and 11 should be zero.
+ */
+ if (!arm_feature(env, ARM_FEATURE_CRC) || op1 == 0x3 ||
+ (c & 0xd) != 0) {
+ goto illegal_op;
+ }
+
+ rn = extract32(insn, 16, 4);
+ rd = extract32(insn, 12, 4);
+
+ tmp = load_reg(s, rn);
+ tmp2 = load_reg(s, rm);
+ tmp3 = tcg_const_i32(1 << op1);
+ if (c & 0x2) {
+ gen_helper_crc32c(tmp, tmp, tmp2, tmp3);
+ } else {
+ gen_helper_crc32(tmp, tmp, tmp2, tmp3);
+ }
+ tcg_temp_free_i32(tmp2);
+ tcg_temp_free_i32(tmp3);
+ store_reg(s, rd, tmp);
+ break;
+ }
case 0x5: /* saturating add/subtract */
ARCH(5TE);
rd = (insn >> 12) & 0xf;
@@ -9145,6 +9175,32 @@ static int disas_thumb2_insn(CPUARMState *env,
DisasContext *s, uint16_t insn_hw
case 0x18: /* clz */
gen_helper_clz(tmp, tmp);
break;
+ case 0x20:
+ case 0x21:
+ case 0x22:
+ case 0x28:
+ case 0x29:
+ case 0x2a:
+ {
+ /* crc32/crc32c */
+ uint32_t sz = op & 0x3;
+ uint32_t c = op & 0x8;
+
+ if (!arm_feature(env, ARM_FEATURE_CRC)) {
+ goto illegal_op;
+ }
+
+ tmp2 = load_reg(s, rm);
+ tmp3 = tcg_const_i32(1 << sz);
+ if (c) {
+ gen_helper_crc32c(tmp, tmp, tmp2, tmp3);
+ } else {
+ gen_helper_crc32(tmp, tmp, tmp2, tmp3);
+ }
+ tcg_temp_free_i32(tmp2);
+ tcg_temp_free_i32(tmp3);
+ break;
+ }
default:
goto illegal_op;
}
--
1.8.1.4
