Commit Graph

92 Commits

Author SHA1 Message Date
Rafael J. Wysocki
7e1c1a82f5 Merge branch 'acpi-headers'
* acpi-headers:
  ACPI: Add support to force header inclusion rules for <acpi/acpi.h>.
  ACPI / SFI: Fix wrong <acpi/acpi.h> inclusion in SFI/ACPI wrapper - table definitions.
  ACPICA: Linux: Allow ACPICA inclusion for CONFIG_ACPI=n builds.
  ACPICA: Linux: Add support to exclude <asm/acenv.h> inclusion.
  ACPICA: Linux: Add stub implementation of ACPICA 64-bit mathematics.
  ACPICA: Linux: Add stub support for Linux specific variables and functions.
2014-07-27 23:52:05 +02:00
Lv Zheng
417b4a73b6 ACPI: Add support to force header inclusion rules for <acpi/acpi.h>.
As there is only CONFIG_ACPI=n processing in the <linux/acpi.h>, it is not
safe to include <acpi/acpi.h> directly for source out of Linux ACPI
subsystems.

This patch adds error messaging to warn developers of such wrong
inclusions.

In order not to be bisected and reverted as a wrong commit, warning
messages are carefully split into a seperate patch other than the wrong
inclusion cleanups.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-23 01:10:45 +02:00
Lv Zheng
d334c823b2 ACPICA: Linux: Add support to exclude <asm/acenv.h> inclusion.
The forthcoming patch will make <acpi/acpi.h> to be visible to all kernel
source code. Thus for the architectures that do not support ACPI and
haven't implemented <asm/acenv.h>, we need to make it excluded.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-23 01:10:44 +02:00
Lv Zheng
daba25d6e0 ACPICA: Linux: Add stub implementation of ACPICA 64-bit mathematics.
This patch adds default 64-bit mathematics in aclinux.h using do_div(). As
do_div() can be used for all Linux architectures, this can also be used as
stub macros for ACPICA 64-bit mathematics.

These macros are required by drivers/acpi/utmath.c when ACPI_USE_NATIVE_DIVIDE
is not defined.  It is used by ACPICA, so currently this is only meaningful to
CONFIG_ACPI builds.  So the kernel will not use these macros unless CONFIG_ACPI
is defined and ACPI_USE_DIVIDE is not defined.

For 64-bit kernels:
In include/acpi/actypes.h, for ACPI_MACHINE_WIDTH=64,
ACPI_USE_NATIVE_DIVIDE will be defined, thus these macros are not used.
In include/acpi/platform/aclinux.h, for __KERNEL__ surrounded code,
ACPI_MACHINE_WIDTH is defined to be BITS_PER_LONG.
So all 64-bit kernels do not use these macros.

For 32-bit kernels:
As mentioned above, these macros will be used when BITS_PER_LONG is 32.
Thus currently the i328 kernels are the only users for these macros.
But they won't use this default implementation provided by this patch,
because in arch/x86/include/asm/acenv.h, there are already overrides
implemented.  So these default macros are not used by 32-bit x86 (i386)
kernels.

These macros will only be used by future non x86 32-bit architectures
that try to support ACPI in Linux kernel.

During the period they do not have arch specific implementations of such
macros, we can avoid build errors for them.

And since they can see ACPICA functioning without implementing any arch
specific environment tunings, we  can also avoid function errors for
them.

As this implementation is not performance friendly, those architectures
still need to implement real support in the end.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-23 01:07:31 +02:00
Lv Zheng
fbee6b21a3 ACPICA: acpidump: Add memory/string OSL usage to improve portability
This patch adds code to use generic OSL for acpidump to improve the
portability of this tool. Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-08 14:22:27 +02:00
Lv Zheng
2e70da4c51 ACPICA: Utilities: Introduce acpi_log_error() to improve portability
Invocations like fprintf(stderr) and perror() are not portable, this patch
introduces acpi_log_error() as a replacement, it is implemented using new
portable API - acpi_ut_file_vprintf().

Note that though acpi_os_initialize() need to be invoked prior than using
this new API, since no users are introduced in this patch, such invocations
are not added for applications that link utprint.c in this patch. Futher
patches that introduce users of acpi_log_error() should take care of this.

This patch is only useful for ACPICA applications, most of which are not
shipped in the Linux kernel.

Note that follow-up commits will update acpidump to use this new API to
improve portability. Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-08 14:22:26 +02:00
Lv Zheng
afbdc6aece ACPICA: OSL: Update environments to improve portability
This patch contains some environment updates that will be used by acpidump
because:
 1. The follow-up commits will release osunixxf.c to the Linux kernel for
    acpidump to link, and
 2. Such environment settings will be used to avoid linkage issues.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-08 14:22:25 +02:00
Lv Zheng
a238317ce8 ACPI: Clean up acpi_os_map/unmap_memory() to eliminate __iomem.
ACPICA doesn't include protections around address space checking, Linux
build tests always complain increased sparse warnings around ACPICA
internal acpi_os_map/unmap_memory() invocations.  This patch tries to fix
this issue permanently.

There are 2 choices left for us to solve this issue:
 1. Add __iomem address space awareness into ACPICA.
 2. Remove sparse checker of __iomem from ACPICA source code.

This patch chooses solution 2, because:
 1.  Most of the acpi_os_map/unmap_memory() invocations are used for ACPICA.
     table mappings, which in fact are not IO addresses.
 2.  The only IO addresses usage is for "system memory space" mapping code in:
      drivers/acpi/acpica/exregion.c
      drivers/acpi/acpica/evrgnini.c
      drivers/acpi/acpica/exregion.c
    The mapped address is accessed in the handler of "system memory space"
    - acpi_ex_system_memory_space_handler().  This function in fact can be
    changed to invoke acpi_os_read/write_memory() so that __iomem can
    always be type-casted in the OSL layer.

According to the above investigation, we drew the following conclusion:
It is not a good idea to introduce __iomem address space awareness into
ACPICA mostly in order to protect non-IO addresses.

We can simply remove __iomem for acpi_os_map/unmap_memory() to remove
__iomem checker for ACPICA code. Then we need to enforce external usages
to invoke other APIs that are aware of __iomem address space.
The external usages are:
 drivers/acpi/apei/einj.c
 drivers/acpi/acpi_extlog.c
 drivers/char/tpm/tpm_acpi.c
 drivers/acpi/nvs.c

This patch thus performs cleanups in this way:
 1. Add acpi_os_map/unmap_iomem() to be invoked by non-ACPICA code.
 2. Remove __iomem from acpi_os_map/unmap_memory().

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:08 +02:00
Lv Zheng
92985ef1db ACPICA: Clean up redudant definitions already defined elsewhere
Since mis-order issues have been solved, we can cleanup redundant
definitions that already have defaults in <acpi/platform/acenv.h>.

This patch removes redudant environments for __KERNEL__ surrounded code.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:08 +02:00
Lv Zheng
07d8391433 ACPICA: Linux headers: Add <asm/acenv.h> to remove mis-ordered inclusion of <asm/acpi.h>
There is a mis-order inclusion for <asm/acpi.h>.

As we will enforce including <linux/acpi.h> for all Linux ACPI users, we
can find the inclusion order is as follows:

<linux/acpi.h>
  <acpi/acpi.h>
   <acpi/platform/acenv.h>
    (acenv.h before including aclinux.h)
    <acpi/platform/aclinux.h>
...........................................................................
     (aclinux.h before including asm/acpi.h)
     <asm/acpi.h>                             @Redundant@
      (ACPICA specific stuff)
...........................................................................
...........................................................................
      (Linux ACPI specific stuff) ? - - - - - - - - - - - - +
     (aclinux.h after including asm/acpi.h)   @Invisible@   |
    (acenv.h after including aclinux.h)       @Invisible@   |
   other ACPICA headers                       @Invisible@   |
............................................................|..............
  <acpi/acpi_bus.h>                                         |
  <acpi/acpi_drivers.h>                                     |
  <asm/acpi.h> (Excluded)                                   |
   (Linux ACPI specific stuff) ! <- - - - - - - - - - - - - +

NOTE that, in ACPICA, <acpi/platform/acenv.h> is more like Kconfig
generated <generated/autoconf.h> for Linux, it is meant to be included
before including any ACPICA code.

In the above figure, there is a question mark for "Linux ACPI specific
stuff" in <asm/acpi.h> which should be included after including all other
ACPICA header files.  Thus they really need to be moved to the position
marked with exclaimation mark or the definitions in the blocks marked with
"@Invisible@" will be invisible to such architecture specific "Linux ACPI
specific stuff" header blocks.  This leaves 2 issues:
1. All environmental definitions in these blocks should have a copy in the
   area marked with "@Redundant@" if they are required by the "Linux ACPI
   specific stuff".
2. We cannot use any ACPICA defined types in <asm/acpi.h>.

This patch splits architecture specific ACPICA stuff from <asm/acpi.h> to
fix this issue.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:07 +02:00
Lv Zheng
d13bd5a602 ACPICA: Linux headers: Add <acpi/platform/aclinuxex.h>
From ACPICA's perspective, <acpi/actypes.h> should be included after
inclusion of <acpi/platform/acenv.h>.  But currently in Linux,
<acpi/platform/aclinux.h> included by <acpi/platform/acenv.h> has
included <acpi/actypes.h> to find ACPICA types for inline functions.

This causes the following problem:
1. Redundant code in <asm/acpi.h> and <acpi/platform/aclinux.h>:
   Linux must be careful to keep conditions for <acpi/actypes.h> inclusion
   consistent with the conditions for <acpi/platform/aclinux.h> inclusion.
   Which finally leads to the issue that we have to keep many useless macro
   definitions in <acpi/platform/aclinux.h> or <asm/acpi.h>.
   Such conditions include:
     COMPILER_DEPENDENT_UINT64
     COMPILER_DEPENDENT_INT64
     ACPI_INLINE
     ACPI_SYSTEM_XFACE
     ACPI_EXTERNAL_XFACE
     ACPI_INTERNAL_XFACE
     ACPI_INTERNAL_VAR_XFACE
     ACPI_MUTEX_TYPE
     DEBUGGER_THREADING
     ACPI_ACQUIRE_GLOBAL_LOCK
     ACPI_RELEASE_GLOBAL_LOCK
     ACPI_FLUSH_CPU_CACHE
   They have default implementations in <include/acpi/platform/acenv.h>
   while Linux need to keep a copy in <asm/acpi.h> to avoid build errors.

This patch introduces <acpi/platform/aclinuxex.h> to fix this issue by
splitting conditions and declarations (most of them are inline functions)
into 2 header files so that the wrong inclusion of <acpi/actypes.h> can be
removed from <acpi/platform/aclinux.h>.

This patch also removes old ACPI_NATIVE_INTERFACE_HEADER mechanism which is
not preferred by Linux and adds the platform/acenvex.h to be the solution
to solve this issue.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:07 +02:00
Lv Zheng
636fcfefa2 ACPICA: Linux headers: Remove ACPI_PREEMPTION_POINT() due to no usages.
This patch deletes deprecated ACPI_PREEMPTION_POINT(), there is no user
for it in Linux kernel now.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-27 18:13:07 +02:00
Lv Zheng
42873a84a2 ACPICA: Linux header: Add support for stubbed externals.
Linux wants to include all header files but leave empty inline
stub variables for a feature that is not configured during build.

This patch configures ACPICA external globals/macros/functions out and
defines them into no-op when CONFIG_ACPI is not enabled.  Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-07 00:55:01 +02:00
Colin Ian King
72bdad9692 ACPICA: Linux-specific header: Add support for PPC64 compilation.
Adds PPC64 as a 64-bit architecture. Colin Ian King.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-20 22:59:38 +02:00
Lv Zheng
a3a80da3ef ACPICA: Clean up comment divergences in aclinux.h
When the following commmit is back ported to ACPICA, comments have been
updated:
  Subject: ACPICA: Linux-specific header: Update support for Linux/acpi
           applications.

This patch back ports the differences between the ACPICA upstream and
Linux.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
[rjw: Subject]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-20 22:59:37 +02:00
Bob Moore
7ed8232648 ACPICA: gcc-specific: Fix possible issue with the strchr function.
Some versions of gcc implement strchr via a macro, which either
contains bugs or can provoke a bug in the compiler. This change
fixes a possible compile-time error when using this function.
The problem is usually seen when compiling the getopt.c module.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-20 22:59:37 +02:00
Rafael J. Wysocki
bcef50814c Merge branch 'acpi-config' into acpica
Conflicts:
	include/acpi/platform/aclinux.h
2014-03-18 01:53:28 +01:00
Lv Zheng
e252652fb2 ACPICA: acpidump: Remove integer types translation protection.
Remove translation protection for applications as Linux tools folder will
start to use such types.

In Linux kernel source tree, after removing this translation protection,
the u8/u16/u32/u64/s32/s64 typedefs are exposed for both __KERNEL__ builds
and !__KERNEL__ builds (tools/power/acpi) and the original definitions of
ACPI_UINT8/16/32/64_MAX are changed.

For !__KERNEL__ builds, this kind of defintions should already been tested
by the distribution vendors that are distributing binary ACPICA package and
we've achieved the successful built/run test result in the kernel source
tree.

For __KERNEL__ builds, there are 2 things affected:
1. u8/u16/u32/u64/s32/s64 type definitions:
   Since Linux has already type defined u8/u16/u32/u64/s32/s64 in
   include/uapi/asm-generic/int-ll64.h for __KERNEL__.  In order not to
   introduce build regressions where the 2 typedefs are differed,
   ACPI_USE_SYSTEM_INTTYPES is introduced to mask out ACPICA's typedefs.
   It must be defined for Linux __KERNEL__ builds.
2. ACPI_UINT8/16/32/64_MAX definitions:
   Before applying this change:
     ACPI_UINT8_MAX: sizeof (UINT8)
      UINT8: unsigned char
     ACPI_UINT16_MAX: sizeof (UINT16)
      UINT16: unsigned short
     ACPI_UINT32_MAX: sizeof (UINT32)
      INT32: int
      UINT32: unsigned int
     ACPI_UINT64_MAX: sizeof (UINT64)
      INT64: COMPILER_DEPENDENT_INT64
       COMPILER_DEPENDENT_INT64: signed long (IA64) or
                                 signed long long (IA32)
      UINT64: COMPILER_DEPENDENT_UINT64
       COMPILER_DEPENDENT_UINT64: unsigned long (IA64) or
                                  unsigned long long (IA32)
   After applying this change:
     ACPI_UINT8_MAX: sizeof (u8)
      u8: unsigned char
      UINT8: (removed from actypes.h)
     ACPI_UINT16_MAX: sizeof (u16)
      u16: unsigned short
      UINT16: (removed from actypes.h)
     ACPI_UINT32_MAX: sizeof (u32)
      INT32/UINT32: (removed from actypes.h)
      s32: signed int
      u32: unsigned int
     ACPI_UINT64_MAX: sizeof (u64)
      INT64/UINT64: (removed from actypes.h)
      u64: unsigned long long
      s64: signed long long
      COMPILER_DEPENDENT_INT64: signed long (IA64) (not used any more)
                                signed long long (IA32) (not used any more)
      COMPILER_DEPENDENT_UINT64: unsigned long (IA64) (not used any more)
                                 unsigned long long (IA32) (not used any more)
   All definitions are equal except ACPI_UINT64_MAX for CONFIG_IA64.  It
   is changed from sizeof(unsigned long) to sizeof(unsigned long long).
   By investigation, 64bit Linux kernel build is LP64 compliant, i.e.,
   sizeof(long) and (pointer) are 64.  As sizeof(unsigned long) equals to
   sizeof(unsigned long long) on IA64 platform where CONFIG_64BIT cannot be
   disabled, this change actually will not affect the value of
   ACPI_UINT64_MAX on IA64 platforms.

This patch is necessary for the ACPICA's acpidump tool to build
correctly.  Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-13 16:21:15 +01:00
Lv Zheng
7e66b46b24 ACPICA: acpidump: Add sparse declarators support.
Linux kernel resident ACPICA headers include some sparse declarators for
kernel static checkers.  This patch adds code to disable them for non
__KERNEL__ defined code so that it is possible for the ACPICA user space
tool's source files to be built with Linux kernel ACPICA header files
included.  Lv Zheng.

Linux kernel build is not affected by this commit.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-13 15:29:38 +01:00
Bob Moore
fbb7a2dc2b ACPICA: Update ACPICA copyrights to 2014.
Update ACPICA copyrights to 2014. Includes all source headers and
signons for the various tools.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-11 00:30:25 +01:00
Al Stone
af1ae78abb ACPI: introduce CONFIG_ACPI_REDUCED_HARDWARE_ONLY
ACPI hardware reduced mode exists to allow newer platforms to use a
simpler form of ACPI that does not require supporting legacy versions
of the specification and their associated hardware.  This mode was
introduced in the ACPI 5.0 specification.

The ACPI hardware reduced mode is supposed to be used on systems
having the HW_REDUCED_ACPI flag set in the FADT.  ACPICA checks
that flag to determine whether or not it should work in the HW
reduced mode and there are pieces of code in it that will never
be used in that case.

Since some architecutres will always use the ACPI HW reduced mode,
it doesn't make sense for them to ever compile support for anything
else.  Thus, they should set the flag ACPI_REDUCED_HARDWARE to TRUE
in the ACPICA source.  To enable them to do that, introduce a new
kernel configuration option, CONFIG_ACPI_REDUCED_HARDWARE_ONLY, that
will cause the ACPICA's ACPI_REDUCED_HARDWARE flag to be TRUE when
set.

Introducing this configuration item is based on suggestions from Lv
Zheng saying that this does not belong in ACPICA, but rather to the
Linux kernel itself.

References: http://www.spinics.net/lists/linux-acpi/msg46369.html
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Al Stone <al.stone@linaro.org>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-05 12:28:07 +01:00
Lv Zheng
71487f3ffd ACPICA: Utilities: Cleanup declarations of the acpi_gbl_debug_file global.
This global is acting as an OSL global variable, implemented in the
oswinxf.c and osunixxf.c.

This patch cleans up the definition of this variable so that new utilities
do not need to define it in order to link.

Linux kernel behaviour is not affected as the changes only applies to the
ACPICA userspace utilities which are not shipped in the kernel currently.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-08 15:31:39 +01:00
Bob Moore
a2c8633b40 ACPICA: Update ACPI example code to make it an actual working program.
Previously, the example code (tools/examples) showed the ACPICA
init code, but was not an actual working program. Added ACPI tables
to make it actually function.

Linux kernel behaviour is not affected as the change only applies
to the ACPICA userspace utilities which are not shipped in the
kernel currently.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-08 15:31:38 +01:00
Lv Zheng
b1c1029d72 ACPICA: Linux Header: Remove unused OSL prototypes.
This patch removes 2 useless OSL prototypes as they are not used by Linux now.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-01-08 15:31:36 +01:00
Rafael J. Wysocki
63ff4d0765 Merge branch 'acpi-hotplug'
* acpi-hotplug:
  ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines
  ACPI / hotplug: Do not execute "insert in progress" _OST
  ACPI / hotplug: Carry out PCI root eject directly
  ACPI / hotplug: Merge device hot-removal routines
  ACPI / hotplug: Make acpi_bus_hot_remove_device() internal
  ACPI / hotplug: Simplify device ejection routines
  ACPI / hotplug: Fix handle_root_bridge_removal()
  ACPI / hotplug: Refuse to hot-remove all objects with disabled hotplug
  ACPI / scan: Start matching drivers after trying scan handlers
  ACPI: Remove acpi_pci_slot_init() headers from internal.h

Conflicts:
	include/acpi/acpiosxf.h (with the 'acpica' branch)
2013-11-07 19:31:15 +01:00