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Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux
Pull xtensa updates from Chris Zankel:
"Support for the latest MMU architecture that allows for a larger
accessible memory region, and various bug-fixes"
* tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux:
xtensa: Switch to asm-generic/linkage.h
xtensa: fix redboot load address
xtensa: ISS: fix timer_lock usage in rs_open
xtensa: disable IRQs while IRQ handler is running
xtensa: enable lockdep support
xtensa: fix arch_irqs_disabled_flags implementation
xtensa: add irq flags trace support
xtensa: provide custom CALLER_ADDR* implementations
xtensa: add stacktrace support
xtensa: clean up stpill_registers
xtensa: don't use a7 in simcalls
xtensa: don't attempt to use unconfigured timers
xtensa: provide default platform_pcibios_init implementation
xtensa: remove KCORE_ELF again
xtensa: document MMUv3 setup sequence
xtensa: add MMU v3 support
xtensa: fix ibreakenable register update
xtensa: fix oprofile building as module
IRQs are disabled when PS.EXCM is set or PS.INTLEVEL is equal to or
higher than LOCKLEVEL.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Definition of CALLER_ADDR* through __builtin_return_address makes
compiler insert calls to __xtensa_libgcc_window_spill, which in turn
makes fast_syscall_spill_registers syscall that clobbers registers when
called from the kernel mode, leading to invalid opcode exceptions on
return to userspace.
Provide definition for CALLER_ADDR0 as MAKE_PC_FROM_RA(a0, a1) and in
case CONFIG_FRAME_POINTER is enabled extract CALLER_ADDR{1-3} from
stack.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
- remove unused asm parameters;
- fix EXCM bit setting in the PS SR during _spill_registers call.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Added features:
- add support for thread local storage (TLS)
- add accept4 and finit_module syscalls
- support medium-priority interrupts
- add support for dc232c processor variant
- support file-base simulated disk for ISS simulator
Bug fixes:
- fix return values returned by the str[n]cmp functions
- avoid mmap cache aliasing
- fix handling of 'windowed registers' in ptrace
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Merge tag 'xtensa-next-20130225' of git://github.com/czankel/xtensa-linux
Pull xtensa update from Chris Zankel:
"Added features:
- add support for thread local storage (TLS)
- add accept4 and finit_module syscalls
- support medium-priority interrupts
- add support for dc232c processor variant
- support file-base simulated disk for ISS simulator
Bug fixes:
- fix return values returned by the str[n]cmp functions
- avoid mmap cache aliasing
- fix handling of 'windowed registers' in ptrace"
* tag 'xtensa-next-20130225' of git://github.com/czankel/xtensa-linux:
xtensa: add accept4 syscall
xtensa: add support for TLS
xtensa: add missing include asm/uaccess.h to checksum.h
xtensa: do not enable GENERIC_GPIO by default
xtensa: complete ptrace handling of register windows
xtensa: add support for oprofile
xtensa: move spill_registers to traps.h
xtensa: ISS: add host file-based simulated disk
xtensa: fix str[n]cmp return value
xtensa: avoid mmap cache aliasing
xtensa: add finit_module syscall
xtensa: pull signal definitions from signal-defs.h
xtensa: fix ipc_parse_version selection
xtensa: dispatch medium-priority interrupts
xtensa: Add config files for Diamond 233L - Rev C processor variant
xtensa: use new common dtc rule
xtensa: rename prom_update_property to of_update_property
The Xtensa architecture provides a global register called THREADPTR
for the purpose of Thread Local Storage (TLS) support. This allows us
to use a fairly simple implementation, keeping the thread pointer in
the regset and simply saving and restoring it upon entering/exiting
the from user space.
Signed-off-by: Chris Zankel <chris@zankel.net>
This fixes the following build errors seen in the linux-next:
arch/xtensa/include/asm/checksum.h:247:2: error: implicit declaration of
function 'access_ok' [-Werror=implicit-function-declaration]
arch/xtensa/include/asm/checksum.h:247:16: error: 'VERIFY_WRITE' undeclared
(first use in this function)
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
str[n]cmp functions return negative value if the first string is less
than the second, positive value if the first string is greater than the
second and zero if they are equal. This is important when these
functions are used for sorting/binary search.
With incorrect strcmp return value bsearch was always failing in the
find_symbol_in_section making it impossible to load any module.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Provide arch_get_unmapped_area function aligning shared memory mapping
addresses to the biggest of the page size or the cache way size. That
guarantees that corresponding virtual addresses of shared mappings are
cached by the same cache sets.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Add support for dispatching medium-priority interrupts, that is,
interrupts of priority levels 2 to EXCM_LEVEL. IRQ handling may be
preempted by higher priority IRQ.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Pull signal handling cleanups from Al Viro:
"This is the first pile; another one will come a bit later and will
contain SYSCALL_DEFINE-related patches.
- a bunch of signal-related syscalls (both native and compat)
unified.
- a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE
(fixing several potential problems with missing argument
validation, while we are at it)
- a lot of now-pointless wrappers killed
- a couple of architectures (cris and hexagon) forgot to save
altstack settings into sigframe, even though they used the
(uninitialized) values in sigreturn; fixed.
- microblaze fixes for delivery of multiple signals arriving at once
- saner set of helpers for signal delivery introduced, several
architectures switched to using those."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits)
x86: convert to ksignal
sparc: convert to ksignal
arm: switch to struct ksignal * passing
alpha: pass k_sigaction and siginfo_t using ksignal pointer
burying unused conditionals
make do_sigaltstack() static
arm64: switch to generic old sigaction() (compat-only)
arm64: switch to generic compat rt_sigaction()
arm64: switch compat to generic old sigsuspend
arm64: switch to generic compat rt_sigqueueinfo()
arm64: switch to generic compat rt_sigpending()
arm64: switch to generic compat rt_sigprocmask()
arm64: switch to generic sigaltstack
sparc: switch to generic old sigsuspend
sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE
sparc: kill sign-extending wrappers for native syscalls
kill sparc32_open()
sparc: switch to use of generic old sigaction
sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE
mips: switch to generic sys_fork() and sys_clone()
...
__ARCH_WANT_SYS_RT_SIGACTION,
__ARCH_WANT_SYS_RT_SIGSUSPEND,
__ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND,
__ARCH_WANT_COMPAT_SYS_SCHED_RR_GET_INTERVAL - not used anymore
CONFIG_GENERIC_{SIGALTSTACK,COMPAT_RT_SIG{ACTION,QUEUEINFO,PENDING,PROCMASK}} -
can be assumed always set.
Only alpha and sparc are unusual - they have ka_restorer in it.
And nobody needs that exposed to userland.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Switch from __ARCH_WANT_SYS_RT_SIGACTION to opposite
(!CONFIG_ODD_RT_SIGACTION); the only two architectures that
need it are alpha and sparc. The reason for use of CONFIG_...
instead of __ARCH_... is that it's needed only kernel-side
and doing it that way avoids a mess with include order on many
architectures.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
xtensa/allmodconfig:
drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_mmap’:
drivers/media/v4l2-core/videobuf2-dma-contig.c:204: error: implicit declaration of function ‘dma_mmap_coherent’
drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_get_base_sgt’:
drivers/media/v4l2-core/videobuf2-dma-contig.c:387: error: implicit declaration of function ‘dma_get_sgtable’
For architectures using dma_map_ops, dma_mmap_coherent() and
dma_get_sgtable() are provided in <asm-generic/dma-mapping-common.h>.
Xtensa does not use dma_map_ops, hence it should implement them itself.
For now, use dummy implementations that just return -EINVAL, until the API
has been finalized.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
* a set of patches from Lars-Peter Clausen to generalize asm/mmu.h
and use it in the architectures that don't need any special handling.
* A patch from Will Deacon to remove the {read,write}s{b,w,l} as
discussed during the arm64 review
* A patch from James Hogan that helps with the meta architecture
series.
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Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanup from Arnd Bergmann:
"These are a few cleanups for asm-generic:
- a set of patches from Lars-Peter Clausen to generalize asm/mmu.h
and use it in the architectures that don't need any special
handling.
- A patch from Will Deacon to remove the {read,write}s{b,w,l} as
discussed during the arm64 review
- A patch from James Hogan that helps with the meta architecture
series."
* tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
xtensa: Use generic asm/mmu.h for nommu
h8300: Use generic asm/mmu.h
c6x: Use generic asm/mmu.h
asm-generic/mmu.h: Add support for FDPIC
asm-generic/mmu.h: Remove unused vmlist field from mm_context_t
asm-generic: io: remove {read,write} string functions
asm-generic/io.h: remove asm/cacheflush.h include
Pull signal handling cleanups from Al Viro:
"sigaltstack infrastructure + conversion for x86, alpha and um,
COMPAT_SYSCALL_DEFINE infrastructure.
Note that there are several conflicts between "unify
SS_ONSTACK/SS_DISABLE definitions" and UAPI patches in mainline;
resolution is trivial - just remove definitions of SS_ONSTACK and
SS_DISABLED from arch/*/uapi/asm/signal.h; they are all identical and
include/uapi/linux/signal.h contains the unified variant."
Fixed up conflicts as per Al.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
alpha: switch to generic sigaltstack
new helpers: __save_altstack/__compat_save_altstack, switch x86 and um to those
generic compat_sys_sigaltstack()
introduce generic sys_sigaltstack(), switch x86 and um to it
new helper: compat_user_stack_pointer()
new helper: restore_altstack()
unify SS_ONSTACK/SS_DISABLE definitions
new helper: current_user_stack_pointer()
missing user_stack_pointer() instances
Bury the conditionals from kernel_thread/kernel_execve series
COMPAT_SYSCALL_DEFINE: infrastructure
All architectures have
CONFIG_GENERIC_KERNEL_THREAD
CONFIG_GENERIC_KERNEL_EXECVE
__ARCH_WANT_SYS_EXECVE
None of them have __ARCH_WANT_KERNEL_EXECVE and there are only two callers
of kernel_execve() (which is a trivial wrapper for do_execve() now) left.
Kill the conditionals and make both callers use do_execve().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Remove heading and trailing spaces, trim trailing lines, and wrap lines
that are longer than 80 characters.
Signed-off-by: Chris Zankel <chris@zankel.net>
Device trees allow specification of hardware topology and device
parameters at runtime instead of hard-coding them in platform setup
code. This allows running single binary kernel on a range of compatible
boards.
New boot parameters tag BP_TAG_FDT is allocated and a pointer to flat
device tree is passed in it.
Note that current interrupt mapping scheme uses single cell for
interrupt identification. That means that IRQ numbers used in DTS must
be CPU internal IRQ numbers, not external. It is possible to extend
interrupt identification to two cells, and use second cell to tell
external IRQ numbers form internal. That would allow to use single DTS
on multiple boards with different mapping of external IRQ numbers.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Add a brief sanity test of S32C1I functionality. This instruction
is needed by the kernel and userland as part of the base ABI
(including GCC atomic builtins, certain threading packages, future
atomic support in the C++ standard, etc). However, correct operation
of this instruction requires some cooperation by hardware external to
the processor (such as bus bridge, bus fabric, or memory controller).
Minimally exercising this mechanism and reporting explicit status
early in the boot process is helpful to chip vendors using the Linux
kernel as a benchmark of correctness of hardware.
As it turns out, S32C1I is not exercised by the kernel and by uClibc
based userland as of early June 2008. This is expected to change
soon as both incorporate more recent open source developments.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
trap_set_handler sets new C-handler in the exception table and returns
previous handler.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
In order to use S32C1I instruction on cores with ATOMCTL SR the register
must be properly initialized.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Although scompare1 may be saved/restored by xchal_ncp_{load,store}
macros, explicit save/restore of registers manipulated by the kernel
itself is considered more correct.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
This fixes the following allmodconfig build error:
drivers/uio/uio_dmem_genirq.c:95:18: error: 'DMA_ERROR_CODE' undeclared (first use in this function)
drivers/uio/uio_dmem_genirq.c:238:18: error: 'DMA_ERROR_CODE' undeclared (first use in this function)
make[3]: *** [drivers/uio/uio_dmem_genirq.o] Error 1
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Pull big execve/kernel_thread/fork unification series from Al Viro:
"All architectures are converted to new model. Quite a bit of that
stuff is actually shared with architecture trees; in such cases it's
literally shared branch pulled by both, not a cherry-pick.
A lot of ugliness and black magic is gone (-3KLoC total in this one):
- kernel_thread()/kernel_execve()/sys_execve() redesign.
We don't do syscalls from kernel anymore for either kernel_thread()
or kernel_execve():
kernel_thread() is essentially clone(2) with callback run before we
return to userland, the callbacks either never return or do
successful do_execve() before returning.
kernel_execve() is a wrapper for do_execve() - it doesn't need to
do transition to user mode anymore.
As a result kernel_thread() and kernel_execve() are
arch-independent now - they live in kernel/fork.c and fs/exec.c
resp. sys_execve() is also in fs/exec.c and it's completely
architecture-independent.
- daemonize() is gone, along with its parts in fs/*.c
- struct pt_regs * is no longer passed to do_fork/copy_process/
copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.
- sys_fork()/sys_vfork()/sys_clone() unified; some architectures
still need wrappers (ones with callee-saved registers not saved in
pt_regs on syscall entry), but the main part of those suckers is in
kernel/fork.c now."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
do_coredump(): get rid of pt_regs argument
print_fatal_signal(): get rid of pt_regs argument
ptrace_signal(): get rid of unused arguments
get rid of ptrace_signal_deliver() arguments
new helper: signal_pt_regs()
unify default ptrace_signal_deliver
flagday: kill pt_regs argument of do_fork()
death to idle_regs()
don't pass regs to copy_process()
flagday: don't pass regs to copy_thread()
bfin: switch to generic vfork, get rid of pointless wrappers
xtensa: switch to generic clone()
openrisc: switch to use of generic fork and clone
unicore32: switch to generic clone(2)
score: switch to generic fork/vfork/clone
c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
mn10300: switch to generic fork/vfork/clone
h8300: switch to generic fork/vfork/clone
tile: switch to generic clone()
...
Conflicts:
arch/microblaze/include/asm/Kbuild
The nommu portion of mmu.h of the extensa platform is basically the same as the
asm-generic mmu.h. So use it instead.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
In order to promote interoperability between userspace tracers and ftrace,
add a trace_clock that reports raw TSC values which will then be recorded
in the ring buffer. Userspace tracers that also record TSCs are then on
exactly the same time base as the kernel and events can be unambiguously
interlaced.
Tested: Enabled a tracepoint and the "tsc" trace_clock and saw very large
timestamp values.
v2:
Move arch-specific bits out of generic code.
v3:
Rename "x86-tsc", cleanups
v7:
Generic arch bits in Kbuild.
Google-Bug-Id: 6980623
Link: http://lkml.kernel.org/r/1352837903-32191-1-git-send-email-dhsharp@google.com
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Signed-off-by: David Sharp <dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Xtensa implements a method that allows to generate a arbitrary output
for each system call by defining the __SYSCALL(number, function, num_args).
This usually requires to include uapi/unistd.h twice. Instead of removing
the guard agains multiple inclusion entirely, allow to include unistd.h again
only if __SYSCALL is defined. Note that __SYSCALL gets always undefined at
the end of the file.
Signed-off-by: Chris Zankel <chris@zankel.net>
