[Qemu-devel] [PATCH 0/6] Improve getauxval support

[Qemu-devel] [PATCH 0/6] Improve getauxval support

[Richard Henderson]

The getauxval routine was added to glibc for 2.16.  In order to 
better support qemu on systems prior to 2.16, add a qemu_getauxval
entry point, and add the relevant defines to our own elf.h.


r~


Richard Henderson (6):
  osdep: Create qemu_getauxval and qemu_init_auxval
  tcg-ppc64: Use qemu_getauxval
  tcg-arm: Use qemu_getauxval
  tcg-s390: Use qemu_getauxval in query_facilities
  util: Provide fallback hwcap and platform for powerpc
  util: Use qemu_getauxval in linux qemu_cache_utils_init

 include/elf.h              |  70 ++++++++++++++++++++++
 include/qemu/cache-utils.h |   4 +-
 include/qemu/osdep.h       |  20 +++++++
 linux-user/main.c          |   3 +-
 tcg/arm/tcg-target.c       |  15 ++---
 tcg/ppc64/tcg-target.c     |  11 +---
 tcg/s390/tcg-target.c      |  95 ++++--------------------------
 util/Makefile.objs         |   1 +
 util/cache-utils.c         |  51 +++++++---------
 util/getauxval.c           | 143 +++++++++++++++++++++++++++++++++++++++++++++
 vl.c                       |   3 +-
 11 files changed, 280 insertions(+), 136 deletions(-)
 create mode 100644 util/getauxval.c

-- 
1.8.1.4

[Qemu-devel] [PATCH 1/6] osdep: Create qemu_getauxval and qemu_init_auxval

[Richard Henderson]

Abstract away dependence on a system implementation of getauxval.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/qemu/osdep.h | 20 ++++++++++++
 linux-user/main.c    |  1 +
 util/Makefile.objs   |  1 +
 util/getauxval.c     | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 vl.c                 |  1 +
 5 files changed, 114 insertions(+)
 create mode 100644 util/getauxval.c

diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 26136f1..8d1948b 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -215,4 +215,24 @@ bool fips_get_state(void);
  */
 char *qemu_get_local_state_pathname(const char *relative_pathname);
 
+/* Return a value for an AT_* type in the auxiliary vector.  Return 0 if the
+ * key is not present.  We attempt to emulate AT_HWCAP and AT_PLATFORM as
+ * best we can when real host support is not present.
+ */
+#ifdef _WIN32
+static inline unsigned long qemu_getauxval(unsigned long type) { return 0; }
+#else
+unsigned long qemu_getauxval(unsigned long type);
+#endif
+
+/* If supported and required, locate the auxiliary vector at program startup.
+ *
+ * @envp must be the third argument to main.
+ */
+#if defined(CONFIG_GETAUXVAL) || defined(_WIN32)
+static inline void qemu_init_auxval(char **envp) { }
+#else
+void qemu_init_auxval(char **envp);
+#endif
+
 #endif
diff --git a/linux-user/main.c b/linux-user/main.c
index 03859bc..fae102a 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -3549,6 +3549,7 @@ int main(int argc, char **argv, char **envp)
 
     module_call_init(MODULE_INIT_QOM);
 
+    qemu_init_auxval(envp);
     qemu_cache_utils_init(envp);
 
     if ((envlist = envlist_create()) == NULL) {
diff --git a/util/Makefile.objs b/util/Makefile.objs
index dc72ab0..8e0c929 100644
--- a/util/Makefile.objs
+++ b/util/Makefile.objs
@@ -11,3 +11,4 @@ util-obj-y += iov.o aes.o qemu-config.o qemu-sockets.o uri.o notify.o
 util-obj-y += qemu-option.o qemu-progress.o
 util-obj-y += hexdump.o
 util-obj-y += crc32c.o
+util-obj-y += getauxval.o
diff --git a/util/getauxval.c b/util/getauxval.c
new file mode 100644
index 0000000..55b639c
--- /dev/null
+++ b/util/getauxval.c
@@ -0,0 +1,91 @@
+/*
+ * QEMU access to the auxiliary vector
+ *
+ * Copyright (C) 2013 Red Hat, Inc
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+#include "qemu/osdep.h"
+
+#ifdef CONFIG_GETAUXVAL
+/* Don't inline this in qemu/osdep.h, because pulling in <sys/auxv.h> for
+   the system declaration of getauxval pulls in the system <elf.h>, which
+   conflicts with qemu's version.  */
+
+#include <sys/auxv.h>
+
+unsigned long qemu_getauxval(unsigned long key)
+{
+    return getauxval(key);
+}
+#elif !defined(_WIN32)
+#include "elf.h"
+
+/* Our elf.h doesn't contain Elf32_auxv_t and Elf64_auxv_t, which is ok because
+   that just makes it easier to define it properly for the host here.  */
+typedef struct {
+    unsigned long a_type;
+    unsigned long a_val;
+} ElfW_auxv_t;
+
+static const ElfW_auxv_t *auxv;
+
+void qemu_init_auxval(char **envp)
+{
+#ifdef __linux__
+    /* The auxiliary vector is located just beyond the initial environment.  */
+    while (*envp != NULL)
+        continue;
+    auxv = (const ElfW_auxv_t *)envp;
+#endif
+}
+
+static const char *default_platform(void)
+{
+    return NULL;
+}
+
+static unsigned long default_hwcap(void)
+{
+    return 0;
+}
+
+unsigned long qemu_getauxval(unsigned long type)
+{
+    /* If we were able to find the auxiliary vector, use it.  */
+    if (auxv) {
+        const ElfW_auxv_t *a;
+        for (a = auxv; a->a_type != 0; a++) {
+            if (a->a_type == type) {
+                return a->a_val;
+            }
+        }
+    }
+
+    /* Otherwise, guess defaults for the host based on compiler flags.  */
+    if (type == AT_HWCAP) {
+        return default_hwcap();
+    } else if (type == AT_PLATFORM) {
+        return (unsigned long)default_platform();
+    }
+    return 0;
+}
+#endif
diff --git a/vl.c b/vl.c
index f422a1c..c539fd3 100644
--- a/vl.c
+++ b/vl.c
@@ -2967,6 +2967,7 @@ int main(int argc, char **argv, char **envp)
     init_clocks();
     rtc_clock = host_clock;
 
+    qemu_init_auxval(envp);
     qemu_cache_utils_init(envp);
 
     QLIST_INIT (&vm_change_state_head);
-- 
1.8.1.4

Re: [Qemu-devel] [PATCH 1/6] osdep: Create qemu_getauxval and qemu_init_auxval

[Aurelien Jarno]

On Sat, Aug 17, 2013 at 03:38:03PM -0700, Richard Henderson wrote:
> Abstract away dependence on a system implementation of getauxval.
> 
> Signed-off-by: Richard Henderson <rth@twiddle.net>
> ---
>  include/qemu/osdep.h | 20 ++++++++++++
>  linux-user/main.c    |  1 +
>  util/Makefile.objs   |  1 +
>  util/getauxval.c     | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  vl.c                 |  1 +
>  5 files changed, 114 insertions(+)
>  create mode 100644 util/getauxval.c
> 
> diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
> index 26136f1..8d1948b 100644
> --- a/include/qemu/osdep.h
> +++ b/include/qemu/osdep.h
> @@ -215,4 +215,24 @@ bool fips_get_state(void);
>   */
>  char *qemu_get_local_state_pathname(const char *relative_pathname);
>  
> +/* Return a value for an AT_* type in the auxiliary vector.  Return 0 if the
> + * key is not present.  We attempt to emulate AT_HWCAP and AT_PLATFORM as
> + * best we can when real host support is not present.
> + */
> +#ifdef _WIN32
> +static inline unsigned long qemu_getauxval(unsigned long type) { return 0; }
> +#else
> +unsigned long qemu_getauxval(unsigned long type);
> +#endif
> +
> +/* If supported and required, locate the auxiliary vector at program startup.
> + *
> + * @envp must be the third argument to main.
> + */
> +#if defined(CONFIG_GETAUXVAL) || defined(_WIN32)
> +static inline void qemu_init_auxval(char **envp) { }
> +#else
> +void qemu_init_auxval(char **envp);
> +#endif
> +
>  #endif
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 03859bc..fae102a 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3549,6 +3549,7 @@ int main(int argc, char **argv, char **envp)
>  
>      module_call_init(MODULE_INIT_QOM);
>  
> +    qemu_init_auxval(envp);
>      qemu_cache_utils_init(envp);
>  
>      if ((envlist = envlist_create()) == NULL) {
> diff --git a/util/Makefile.objs b/util/Makefile.objs
> index dc72ab0..8e0c929 100644
> --- a/util/Makefile.objs
> +++ b/util/Makefile.objs
> @@ -11,3 +11,4 @@ util-obj-y += iov.o aes.o qemu-config.o qemu-sockets.o uri.o notify.o
>  util-obj-y += qemu-option.o qemu-progress.o
>  util-obj-y += hexdump.o
>  util-obj-y += crc32c.o
> +util-obj-y += getauxval.o
> diff --git a/util/getauxval.c b/util/getauxval.c
> new file mode 100644
> index 0000000..55b639c
> --- /dev/null
> +++ b/util/getauxval.c
> @@ -0,0 +1,91 @@
> +/*
> + * QEMU access to the auxiliary vector
> + *
> + * Copyright (C) 2013 Red Hat, Inc
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +#include "qemu-common.h"
> +#include "qemu/osdep.h"
> +
> +#ifdef CONFIG_GETAUXVAL
> +/* Don't inline this in qemu/osdep.h, because pulling in <sys/auxv.h> for
> +   the system declaration of getauxval pulls in the system <elf.h>, which
> +   conflicts with qemu's version.  */
> +
> +#include <sys/auxv.h>
> +
> +unsigned long qemu_getauxval(unsigned long key)
> +{
> +    return getauxval(key);
> +}
> +#elif !defined(_WIN32)
> +#include "elf.h"
> +
> +/* Our elf.h doesn't contain Elf32_auxv_t and Elf64_auxv_t, which is ok because
> +   that just makes it easier to define it properly for the host here.  */
> +typedef struct {
> +    unsigned long a_type;
> +    unsigned long a_val;
> +} ElfW_auxv_t;
> +
> +static const ElfW_auxv_t *auxv;
> +
> +void qemu_init_auxval(char **envp)
> +{
> +#ifdef __linux__
> +    /* The auxiliary vector is located just beyond the initial environment.  */
> +    while (*envp != NULL)
> +        continue;

This is basically an endless loop, so QEMU doesn't start on a system
without getauxval support.

> +    auxv = (const ElfW_auxv_t *)envp;
> +#endif
> +}
> +
> +static const char *default_platform(void)
> +{
> +    return NULL;
> +}
> +
> +static unsigned long default_hwcap(void)
> +{
> +    return 0;
> +}
> +
> +unsigned long qemu_getauxval(unsigned long type)
> +{
> +    /* If we were able to find the auxiliary vector, use it.  */
> +    if (auxv) {
> +        const ElfW_auxv_t *a;
> +        for (a = auxv; a->a_type != 0; a++) {
> +            if (a->a_type == type) {
> +                return a->a_val;
> +            }
> +        }
> +    }
> +
> +    /* Otherwise, guess defaults for the host based on compiler flags.  */
> +    if (type == AT_HWCAP) {
> +        return default_hwcap();
> +    } else if (type == AT_PLATFORM) {
> +        return (unsigned long)default_platform();
> +    }
> +    return 0;
> +}
> +#endif
> diff --git a/vl.c b/vl.c
> index f422a1c..c539fd3 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2967,6 +2967,7 @@ int main(int argc, char **argv, char **envp)
>      init_clocks();
>      rtc_clock = host_clock;
>  
> +    qemu_init_auxval(envp);
>      qemu_cache_utils_init(envp);
>  
>      QLIST_INIT (&vm_change_state_head);
> -- 
> 1.8.1.4
> 
> 
> 

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net

[Qemu-devel] [PATCH 2/6] tcg-ppc64: Use qemu_getauxval

[Richard Henderson]

Allow host detection on linux systems without glibc 2.16 or later.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/elf.h          | 34 ++++++++++++++++++++++++++++++++++
 tcg/ppc64/tcg-target.c | 11 ++---------
 2 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/include/elf.h b/include/elf.h
index 58bfbf8..7fdd3df 100644
--- a/include/elf.h
+++ b/include/elf.h
@@ -411,6 +411,40 @@ typedef struct {
 #define R_SPARC_5		44
 #define R_SPARC_6		45
 
+/* Bits present in AT_HWCAP for PowerPC.  */
+
+#define PPC_FEATURE_32                  0x80000000
+#define PPC_FEATURE_64                  0x40000000
+#define PPC_FEATURE_601_INSTR           0x20000000
+#define PPC_FEATURE_HAS_ALTIVEC         0x10000000
+#define PPC_FEATURE_HAS_FPU             0x08000000
+#define PPC_FEATURE_HAS_MMU             0x04000000
+#define PPC_FEATURE_HAS_4xxMAC          0x02000000
+#define PPC_FEATURE_UNIFIED_CACHE       0x01000000
+#define PPC_FEATURE_HAS_SPE             0x00800000
+#define PPC_FEATURE_HAS_EFP_SINGLE      0x00400000
+#define PPC_FEATURE_HAS_EFP_DOUBLE      0x00200000
+#define PPC_FEATURE_NO_TB               0x00100000
+#define PPC_FEATURE_POWER4              0x00080000
+#define PPC_FEATURE_POWER5              0x00040000
+#define PPC_FEATURE_POWER5_PLUS         0x00020000
+#define PPC_FEATURE_CELL                0x00010000
+#define PPC_FEATURE_BOOKE               0x00008000
+#define PPC_FEATURE_SMT                 0x00004000
+#define PPC_FEATURE_ICACHE_SNOOP        0x00002000
+#define PPC_FEATURE_ARCH_2_05           0x00001000
+#define PPC_FEATURE_PA6T                0x00000800
+#define PPC_FEATURE_HAS_DFP             0x00000400
+#define PPC_FEATURE_POWER6_EXT          0x00000200
+#define PPC_FEATURE_ARCH_2_06           0x00000100
+#define PPC_FEATURE_HAS_VSX             0x00000080
+
+#define PPC_FEATURE_PSERIES_PERFMON_COMPAT \
+                                        0x00000040
+
+#define PPC_FEATURE_TRUE_LE             0x00000002
+#define PPC_FEATURE_PPC_LE              0x00000001
+
 /* Bits present in AT_HWCAP, primarily for Sparc32.  */
 
 #define HWCAP_SPARC_FLUSH       1    /* CPU supports flush instruction. */
diff --git a/tcg/ppc64/tcg-target.c b/tcg/ppc64/tcg-target.c
index 0678de2..a53f32a 100644
--- a/tcg/ppc64/tcg-target.c
+++ b/tcg/ppc64/tcg-target.c
@@ -45,15 +45,10 @@ static uint8_t *tb_ret_addr;
 #define GUEST_BASE 0
 #endif
 
-#ifdef CONFIG_GETAUXVAL
-#include <sys/auxv.h>
+#include "elf.h"
 static bool have_isa_2_06;
 #define HAVE_ISA_2_06  have_isa_2_06
 #define HAVE_ISEL      have_isa_2_06
-#else
-#define HAVE_ISA_2_06  0
-#define HAVE_ISEL      0
-#endif
 
 #ifdef CONFIG_USE_GUEST_BASE
 #define TCG_GUEST_BASE_REG 30
@@ -2132,12 +2127,10 @@ static const TCGTargetOpDef ppc_op_defs[] = {
 
 static void tcg_target_init (TCGContext *s)
 {
-#ifdef CONFIG_GETAUXVAL
-    unsigned long hwcap = getauxval(AT_HWCAP);
+    unsigned long hwcap = qemu_getauxval(AT_HWCAP);
     if (hwcap & PPC_FEATURE_ARCH_2_06) {
         have_isa_2_06 = true;
     }
-#endif
 
     tcg_regset_set32 (tcg_target_available_regs[TCG_TYPE_I32], 0, 0xffffffff);
     tcg_regset_set32 (tcg_target_available_regs[TCG_TYPE_I64], 0, 0xffffffff);
-- 
1.8.1.4

[Qemu-devel] [PATCH 3/6] tcg-arm: Use qemu_getauxval

[Richard Henderson]

Allow host detection on linux systems without glibc 2.16 or later.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/elf.h        | 22 ++++++++++++++++++++++
 tcg/arm/tcg-target.c | 15 ++++++---------
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/include/elf.h b/include/elf.h
index 7fdd3df..e95fa95 100644
--- a/include/elf.h
+++ b/include/elf.h
@@ -411,6 +411,28 @@ typedef struct {
 #define R_SPARC_5		44
 #define R_SPARC_6		45
 
+/* Bits present in AT_HWCAP for ARM.  */
+
+#define HWCAP_ARM_SWP		1
+#define HWCAP_ARM_HALF		2
+#define HWCAP_ARM_THUMB		4
+#define HWCAP_ARM_26BIT		8
+#define HWCAP_ARM_FAST_MULT	16
+#define HWCAP_ARM_FPA		32
+#define HWCAP_ARM_VFP		64
+#define HWCAP_ARM_EDSP		128
+#define HWCAP_ARM_JAVA		256
+#define HWCAP_ARM_IWMMXT	512
+#define HWCAP_ARM_CRUNCH	1024
+#define HWCAP_ARM_THUMBEE	2048
+#define HWCAP_ARM_NEON		4096
+#define HWCAP_ARM_VFPv3		8192
+#define HWCAP_ARM_VFPv3D16	16384
+#define HWCAP_ARM_TLS		32768
+#define HWCAP_ARM_VFPv4		65536
+#define HWCAP_ARM_IDIVA		131072
+#define HWCAP_ARM_IDIVT		262144
+
 /* Bits present in AT_HWCAP for PowerPC.  */
 
 #define PPC_FEATURE_32                  0x80000000
diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
index 6c4854d..f56666c 100644
--- a/tcg/arm/tcg-target.c
+++ b/tcg/arm/tcg-target.c
@@ -22,6 +22,8 @@
  * THE SOFTWARE.
  */
 
+#include "elf.h"
+
 /* The __ARM_ARCH define is provided by gcc 4.8.  Construct it otherwise.  */
 #ifndef __ARM_ARCH
 # if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
@@ -56,9 +58,6 @@ static int arm_arch = __ARM_ARCH;
 #ifndef use_idiv_instructions
 bool use_idiv_instructions;
 #endif
-#ifdef CONFIG_GETAUXVAL
-# include <sys/auxv.h>
-#endif
 
 #ifndef NDEBUG
 static const char * const tcg_target_reg_names[TCG_TARGET_NB_REGS] = {
@@ -2030,22 +2029,20 @@ static const TCGTargetOpDef arm_op_defs[] = {
 
 static void tcg_target_init(TCGContext *s)
 {
-#if defined(CONFIG_GETAUXVAL)
     /* Only probe for the platform and capabilities if we havn't already
        determined maximum values at compile time.  */
-# if !defined(use_idiv_instructions)
+#ifndef use_idiv_instructions
     {
-        unsigned long hwcap = getauxval(AT_HWCAP);
+        unsigned long hwcap = qemu_getauxval(AT_HWCAP);
         use_idiv_instructions = (hwcap & HWCAP_ARM_IDIVA) != 0;
     }
-# endif
+#endif
     if (__ARM_ARCH < 7) {
-        const char *pl = (const char *)getauxval(AT_PLATFORM);
+        const char *pl = (const char *)qemu_getauxval(AT_PLATFORM);
         if (pl != NULL && pl[0] == 'v' && pl[1] >= '4' && pl[1] <= '9') {
             arm_arch = pl[1] - '0';
         }
     }
-#endif /* GETAUXVAL */
 
     tcg_regset_set32(tcg_target_available_regs[TCG_TYPE_I32], 0, 0xffff);
     tcg_regset_set32(tcg_target_call_clobber_regs, 0,
-- 
1.8.1.4

[Qemu-devel] [PATCH 4/6] tcg-s390: Use qemu_getauxval in query_facilities

[Richard Henderson]

No need to set up a SIGILL signal handler for detection anymore.

Remove a ton of sanity checks that must be true, given that we're
requiring a 64-bit build (the note about 31-bit KVM is satisfied
by configuring with TCI).

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/elf.h         | 14 ++++++++
 tcg/s390/tcg-target.c | 95 +++++++--------------------------------------------
 2 files changed, 26 insertions(+), 83 deletions(-)

diff --git a/include/elf.h b/include/elf.h
index e95fa95..354ff1a 100644
--- a/include/elf.h
+++ b/include/elf.h
@@ -476,6 +476,20 @@ typedef struct {
 #define HWCAP_SPARC_V9		16
 #define HWCAP_SPARC_ULTRA3	32
 
+/* Bits present in AT_HWCAP for s390.  */
+
+#define HWCAP_S390_ESAN3        1
+#define HWCAP_S390_ZARCH        2
+#define HWCAP_S390_STFLE        4
+#define HWCAP_S390_MSA          8
+#define HWCAP_S390_LDISP        16
+#define HWCAP_S390_EIMM         32
+#define HWCAP_S390_DFP          64
+#define HWCAP_S390_HPAGE        128
+#define HWCAP_S390_ETF3EH       256
+#define HWCAP_S390_HIGH_GPRS    512
+#define HWCAP_S390_TE           1024
+
 /*
  * 68k ELF relocation types
  */
diff --git a/tcg/s390/tcg-target.c b/tcg/s390/tcg-target.c
index f229f1c..6862e2f 100644
--- a/tcg/s390/tcg-target.c
+++ b/tcg/s390/tcg-target.c
@@ -29,6 +29,8 @@
 #error "unsupported code generation mode"
 #endif
 
+#include "elf.h"
+
 /* ??? The translation blocks produced by TCG are generally small enough to
    be entirely reachable with a 16-bit displacement.  Leaving the option for
    a 32-bit displacement here Just In Case.  */
@@ -2234,91 +2236,18 @@ static void sigill_handler(int sig)
 
 static void query_facilities(void)
 {
-    struct sigaction sa_old, sa_new;
-    register int r0 __asm__("0");
-    register void *r1 __asm__("1");
-    int fail;
-
-    memset(&sa_new, 0, sizeof(sa_new));
-    sa_new.sa_handler = sigill_handler;
-    sigaction(SIGILL, &sa_new, &sa_old);
-
-    /* First, try STORE FACILITY LIST EXTENDED.  If this is present, then
-       we need not do any more probing.  Unfortunately, this itself is an
-       extension and the original STORE FACILITY LIST instruction is
-       kernel-only, storing its results at absolute address 200.  */
-    /* stfle 0(%r1) */
-    r1 = &facilities;
-    asm volatile(".word 0xb2b0,0x1000"
-                 : "=r"(r0) : "0"(0), "r"(r1) : "memory", "cc");
-
-    if (got_sigill) {
-        /* STORE FACILITY EXTENDED is not available.  Probe for one of each
-           kind of instruction that we're interested in.  */
-        /* ??? Possibly some of these are in practice never present unless
-           the store-facility-extended facility is also present.  But since
-           that isn't documented it's just better to probe for each.  */
-
-        /* Test for z/Architecture.  Required even in 31-bit mode.  */
-        got_sigill = 0;
-        /* agr %r0,%r0 */
-        asm volatile(".word 0xb908,0x0000" : "=r"(r0) : : "cc");
-        if (!got_sigill) {
-            facilities |= FACILITY_ZARCH_ACTIVE;
-        }
-
-        /* Test for long displacement.  */
-        got_sigill = 0;
-        /* ly %r0,0(%r1) */
-        r1 = &facilities;
-        asm volatile(".word 0xe300,0x1000,0x0058"
-                     : "=r"(r0) : "r"(r1) : "cc");
-        if (!got_sigill) {
-            facilities |= FACILITY_LONG_DISP;
-        }
-
-        /* Test for extended immediates.  */
-        got_sigill = 0;
-        /* afi %r0,0 */
-        asm volatile(".word 0xc209,0x0000,0x0000" : : : "cc");
-        if (!got_sigill) {
-            facilities |= FACILITY_EXT_IMM;
-        }
-
-        /* Test for general-instructions-extension.  */
-        got_sigill = 0;
-        /* msfi %r0,1 */
-        asm volatile(".word 0xc201,0x0000,0x0001");
-        if (!got_sigill) {
-            facilities |= FACILITY_GEN_INST_EXT;
-        }
-    }
-
-    sigaction(SIGILL, &sa_old, NULL);
+    unsigned long hwcap = qemu_getauxval(AT_HWCAP);
 
-    /* The translator currently uses these extensions unconditionally.
-       Pruning this back to the base ESA/390 architecture doesn't seem
-       worthwhile, since even the KVM target requires z/Arch.  */
-    fail = 0;
-    if ((facilities & FACILITY_ZARCH_ACTIVE) == 0) {
-        fprintf(stderr, "TCG: z/Arch facility is required.\n");
-        fprintf(stderr, "TCG: Boot with a 64-bit enabled kernel.\n");
-        fail = 1;
-    }
-    if ((facilities & FACILITY_LONG_DISP) == 0) {
-        fprintf(stderr, "TCG: long-displacement facility is required.\n");
-        fail = 1;
-    }
+    /* Is STORE FACILITY LIST EXTENDED available?  Honestly, I believe this
+       is present on all 64-bit systems, but let's check for it anyway.  */
+    if (hwcap & HWCAP_S390_STFLE) {
+        register int r0 __asm__("0");
+        register void *r1 __asm__("1");
 
-    /* So far there's just enough support for 31-bit mode to let the
-       compile succeed.  This is good enough to run QEMU with KVM.  */
-    if (sizeof(void *) != 8) {
-        fprintf(stderr, "TCG: 31-bit mode is not supported.\n");
-        fail = 1;
-    }
-
-    if (fail) {
-        exit(-1);
+        /* stfle 0(%r1) */
+        r1 = &facilities;
+        asm volatile(".word 0xb2b0,0x1000"
+                     : "=r"(r0) : "0"(0), "r"(r1) : "memory", "cc");
     }
 }
 
-- 
1.8.1.4

[Qemu-devel] [PATCH 5/6] util: Provide fallback hwcap and platform for powerpc

[Richard Henderson]

Allow host "detection" on non-linux hosts.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 util/getauxval.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 54 insertions(+), 2 deletions(-)

diff --git a/util/getauxval.c b/util/getauxval.c
index 55b639c..2e93a14 100644
--- a/util/getauxval.c
+++ b/util/getauxval.c
@@ -60,12 +60,64 @@ void qemu_init_auxval(char **envp)
 
 static const char *default_platform(void)
 {
-    return NULL;
+    const char *ret = NULL;
+
+#ifdef _ARCH_PPC
+# if defined(_ARCH_PWR8)
+    ret = "power8";
+# elif defined(_ARCH_PWR7)
+    ret = "power7";
+# elif defined(_ARCH_PWR6X) || defined(_ARCH_PWR6)
+    ret = "power6";
+# elif defined(_ARCH_PWR5X)
+    ret = "power5+";
+# elif defined(_ARCH_PWR5)
+    ret = "power5";
+# elif defined(_ARCH_PWR4)
+    ret = "power4";
+# else
+    ret = "power3";
+# endif
+#endif /* _ARCH_PPC */
+
+    return ret;
 }
 
 static unsigned long default_hwcap(void)
 {
-    return 0;
+    unsigned long ret = 0;
+
+#ifdef _ARCH_PPC
+# if defined(_ARCH_PWR8) || defined(_ARCH_PWR7)
+    ret |= PPC_FEATURE_ARCH_2_06;
+# elif defined(_ARCH_PWR6X) || defined(_ARCH_PWR6)
+    ret |= PPC_FEATURE_ARCH_2_05;
+# elif defined(_ARCH_PWR5X)
+    ret |= PPC_FEATURE_POWER5_PLUS;
+# elif defined(_ARCH_PWR5)
+    ret |= PPC_FEATURE_POWER5;
+# elif defined(_ARCH_PWR4)
+    ret |= PPC_FEATURE_POWER4;
+# endif
+# if defined(_ARCH_PWR6) /* and later */
+    ret |= PPC_FEATURE_TRUE_LE | PPC_FEATURE_PSERIES_PERFMON_COMPAT;
+# endif
+# if defined(_ARCH_PWR5) /* and later */
+    ret |= PPC_FEATURE_SMT | PPC_FEATURE_ICACHE_SNOOP;
+# endif
+# if defined(_ARCH_PPC64)
+    ret |= PPC_FEATURE_64;
+# endif
+# if defined(__VSX__)
+    ret |= PPC_FEATURE_HAS_VSX;
+# endif
+# if defined(__ALTIVEC__)
+    ret |= PPC_FEATURE_HAS_ALTIVEC;
+# endif
+    ret |= PPC_FEATURE_32 | PPC_FEATURE_HAS_FPU | PPC_FEATURE_HAS_MMU;
+#endif /* _ARCH_PPC */
+
+    return ret;
 }
 
 unsigned long qemu_getauxval(unsigned long type)
-- 
1.8.1.4

[Qemu-devel] [PATCH 6/6] util: Use qemu_getauxval in linux qemu_cache_utils_init

[Richard Henderson]

With this we no longer pass down envp, and thus all systems can have
the same void prototype.  So also eliminate a useless thunk.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 include/qemu/cache-utils.h |  4 ++--
 linux-user/main.c          |  2 +-
 util/cache-utils.c         | 51 ++++++++++++++++++----------------------------
 vl.c                       |  2 +-
 4 files changed, 24 insertions(+), 35 deletions(-)

diff --git a/include/qemu/cache-utils.h b/include/qemu/cache-utils.h
index 2c57f78..211245b 100644
--- a/include/qemu/cache-utils.h
+++ b/include/qemu/cache-utils.h
@@ -12,7 +12,7 @@ struct qemu_cache_conf {
 
 extern struct qemu_cache_conf qemu_cache_conf;
 
-void qemu_cache_utils_init(char **envp);
+void qemu_cache_utils_init(void);
 
 /* mildly adjusted code from tcg-dyngen.c */
 static inline void flush_icache_range(uintptr_t start, uintptr_t stop)
@@ -38,7 +38,7 @@ static inline void flush_icache_range(uintptr_t start, uintptr_t stop)
 }
 
 #else
-#define qemu_cache_utils_init(envp) do { (void) (envp); } while (0)
+#define qemu_cache_utils_init() do { } while (0)
 #endif
 
 #endif /* QEMU_CACHE_UTILS_H */
diff --git a/linux-user/main.c b/linux-user/main.c
index fae102a..b1200ef 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -3550,7 +3550,7 @@ int main(int argc, char **argv, char **envp)
     module_call_init(MODULE_INIT_QOM);
 
     qemu_init_auxval(envp);
-    qemu_cache_utils_init(envp);
+    qemu_cache_utils_init();
 
     if ((envlist = envlist_create()) == NULL) {
         (void) fprintf(stderr, "Unable to allocate envlist\n");
diff --git a/util/cache-utils.c b/util/cache-utils.c
index b94013a..0470030 100644
--- a/util/cache-utils.c
+++ b/util/cache-utils.c
@@ -1,3 +1,4 @@
+#include "qemu-common.h"
 #include "qemu/cache-utils.h"
 
 #if defined(_ARCH_PPC)
@@ -9,31 +10,33 @@ struct qemu_cache_conf qemu_cache_conf = {
 #if defined _AIX
 #include <sys/systemcfg.h>
 
-static void ppc_init_cacheline_sizes(void)
+void qemu_cache_utils_init(void)
 {
     qemu_cache_conf.icache_bsize = _system_configuration.icache_line;
     qemu_cache_conf.dcache_bsize = _system_configuration.dcache_line;
 }
 
 #elif defined __linux__
+#include "qemu/osdep.h"
+#include "elf.h"
 
-#define QEMU_AT_NULL        0
-#define QEMU_AT_DCACHEBSIZE 19
-#define QEMU_AT_ICACHEBSIZE 20
-
-static void ppc_init_cacheline_sizes(char **envp)
+void qemu_cache_utils_init(void)
 {
-    unsigned long *auxv;
-
-    while (*envp++);
+    unsigned long dsize = qemu_getauxval(AT_DCACHEBSIZE);
+    unsigned long isize = qemu_getauxval(AT_ICACHEBSIZE);
 
-    for (auxv = (unsigned long *) envp; *auxv != QEMU_AT_NULL; auxv += 2) {
-        switch (*auxv) {
-        case QEMU_AT_DCACHEBSIZE: qemu_cache_conf.dcache_bsize = auxv[1]; break;
-        case QEMU_AT_ICACHEBSIZE: qemu_cache_conf.icache_bsize = auxv[1]; break;
-        default: break;
+    if (dsize == 0 || isize == 0) {
+        if (dsize == 0) {
+            fprintf(stderr, "getauxval AT_DCACHEBSIZE failed\n");
+        }
+        if (isize == 0) {
+            fprintf(stderr, "getauxval AT_ICACHEBSIZE failed\n");
         }
+        exit(1);
+
     }
+    qemu_cache_conf.dcache_bsize = dsize;
+    qemu_cache_conf.icache_bsize = isize;
 }
 
 #elif defined __APPLE__
@@ -41,7 +44,7 @@ static void ppc_init_cacheline_sizes(char **envp)
 #include <sys/types.h>
 #include <sys/sysctl.h>
 
-static void ppc_init_cacheline_sizes(void)
+void qemu_cache_utils_init(void)
 {
     size_t len;
     unsigned cacheline;
@@ -55,9 +58,8 @@ static void ppc_init_cacheline_sizes(void)
         qemu_cache_conf.icache_bsize = cacheline;
     }
 }
-#endif
 
-#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -65,7 +67,7 @@ static void ppc_init_cacheline_sizes(void)
 #include <sys/types.h>
 #include <sys/sysctl.h>
 
-static void ppc_init_cacheline_sizes(void)
+void qemu_cache_utils_init(void)
 {
     size_t len = 4;
     unsigned cacheline;
@@ -81,17 +83,4 @@ static void ppc_init_cacheline_sizes(void)
 }
 #endif
 
-#ifdef __linux__
-void qemu_cache_utils_init(char **envp)
-{
-    ppc_init_cacheline_sizes(envp);
-}
-#else
-void qemu_cache_utils_init(char **envp)
-{
-    (void) envp;
-    ppc_init_cacheline_sizes();
-}
-#endif
-
 #endif /* _ARCH_PPC */
diff --git a/vl.c b/vl.c
index c539fd3..51d2c18 100644
--- a/vl.c
+++ b/vl.c
@@ -2968,7 +2968,7 @@ int main(int argc, char **argv, char **envp)
     rtc_clock = host_clock;
 
     qemu_init_auxval(envp);
-    qemu_cache_utils_init(envp);
+    qemu_cache_utils_init();
 
     QLIST_INIT (&vm_change_state_head);
     os_setup_early_signal_handling();
-- 
1.8.1.4

Re: [Qemu-devel] [PATCH 0/6] Improve getauxval support

[Richard Henderson]

Ping.

r~

On 08/17/2013 03:38 PM, Richard Henderson wrote:
> The getauxval routine was added to glibc for 2.16.  In order to 
> better support qemu on systems prior to 2.16, add a qemu_getauxval
> entry point, and add the relevant defines to our own elf.h.
> 
> 
> r~
> 
> 
> Richard Henderson (6):
>   osdep: Create qemu_getauxval and qemu_init_auxval
>   tcg-ppc64: Use qemu_getauxval
>   tcg-arm: Use qemu_getauxval
>   tcg-s390: Use qemu_getauxval in query_facilities
>   util: Provide fallback hwcap and platform for powerpc
>   util: Use qemu_getauxval in linux qemu_cache_utils_init
> 
>  include/elf.h              |  70 ++++++++++++++++++++++
>  include/qemu/cache-utils.h |   4 +-
>  include/qemu/osdep.h       |  20 +++++++
>  linux-user/main.c          |   3 +-
>  tcg/arm/tcg-target.c       |  15 ++---
>  tcg/ppc64/tcg-target.c     |  11 +---
>  tcg/s390/tcg-target.c      |  95 ++++--------------------------
>  util/Makefile.objs         |   1 +
>  util/cache-utils.c         |  51 +++++++---------
>  util/getauxval.c           | 143 +++++++++++++++++++++++++++++++++++++++++++++
>  vl.c                       |   3 +-
>  11 files changed, 280 insertions(+), 136 deletions(-)
>  create mode 100644 util/getauxval.c
>