Pull Xtensa updates from Chris Zankel:
"Xtensa improvements for 3.17:
- support highmem on cores with aliasing data cache. Enable highmem
on kc705 by default
- simplify addition of new core variants (no need to modify Kconfig /
Makefiles)
- improve robustness of unaligned access handler and its interaction
with window overflow/underflow exception handlers
- deprecate atomic and spill registers syscalls
- clean up Kconfig: remove orphan MATH_EMULATION, sort 'select'
statements
- wire up renameat2 syscall.
Various fixes:
- fix address checks in dma_{alloc,free}_coherent (runtime BUG)
- fix access to THREAD_RA/THREAD_SP/THREAD_DS (debug build breakage)
- fix TLBTEMP_BASE_2 region handling in fast_second_level_miss
(runtime unrecoverable exception)
- fix a6 and a7 handling in fast_syscall_xtensa (runtime userspace
register clobbering)
- fix kernel/user jump out of fast_unaligned (potential runtime
unrecoverabl exception)
- replace termios IOCTL code definitions with constants (userspace
build breakage)"
* tag 'xtensa-20140830' of git://github.com/czankel/xtensa-linux: (25 commits)
xtensa: deprecate fast_xtensa and fast_spill_registers syscalls
xtensa: don't allow overflow/underflow on unaligned stack
xtensa: fix a6 and a7 handling in fast_syscall_xtensa
xtensa: allow single-stepping through unaligned load/store
xtensa: move invalid unaligned instruction handler closer to its users
xtensa: make fast_unaligned store restartable
xtensa: add double exception fixup handler for fast_unaligned
xtensa: fix kernel/user jump out of fast_unaligned
xtensa: configure kc705 for highmem
xtensa: support highmem in aliasing cache flushing code
xtensa: support aliasing cache in kmap
xtensa: support aliasing cache in k[un]map_atomic
xtensa: implement clear_user_highpage and copy_user_highpage
xtensa: fix TLBTEMP_BASE_2 region handling in fast_second_level_miss
xtensa: allow fixmap and kmap span more than one page table
xtensa: make fixmap region addressing grow with index
xtensa: fix access to THREAD_RA/THREAD_SP/THREAD_DS
xtensa: add renameat2 syscall
xtensa: fix address checks in dma_{alloc,free}_coherent
xtensa: replace IOCTL code definitions with constants
...
Xtensa improvements for 3.17:
- support highmem on cores with aliasing data cache. Enable highmem on kc705
by default;
- simplify addition of new core variants (no need to modify Kconfig /
Makefiles);
- improve robustness of unaligned access handler and its interaction with
window overflow/underflow exception handlers;
- deprecate atomic and spill registers syscalls;
- clean up Kconfig: remove orphan MATH_EMULATION, sort 'select' statements;
- wire up renameat2 syscall.
Various fixes:
- fix address checks in dma_{alloc,free}_coherent (runtime BUG);
- fix access to THREAD_RA/THREAD_SP/THREAD_DS (debug build breakage);
- fix TLBTEMP_BASE_2 region handling in fast_second_level_miss (runtime
unrecoverable exception);
- fix a6 and a7 handling in fast_syscall_xtensa (runtime userspace register
clobbering);
- fix kernel/user jump out of fast_unaligned (potential runtime unrecoverable
exception);
- replace termios IOCTL code definitions with constants (userspace build
breakage).
Signed-off-by: Chris Zankel <chris@zankel.net>
These syscalls are not used by userspace tools for some time now, and
they have issues when called with invalid arguments. It's not worth
changing signal delivery mechanism as we don't expect any new users for
these syscalls. Let's keep them for backwards compatibility under #ifdef,
disabled by default.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Double exceptions that happen during register window overflow/underflow
are handled in the topmost stack frame, as if it was the only exception
that occured. However unaligned access exception handler is special
because it needs to analyze instruction that caused the exception, but
the userspace instruction that triggered window exception is completely
irrelevant. Unaligned data access is rather normal in the generic
userspace code, but stack pointer manipulation must always be done by
architecture-aware code and thus unaligned stack means a serious problem
anyway.
Use the default unaligned access handler that raises SIGBUS in case
of unaligned access in window overflow/underflow handler.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Remove restoring a6 on some return paths and instead modify and restore
it in a single place, using symbolic name.
Correctly restore a7 from PT_AREG7 in case of illegal a6 value.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Update icount when icountlevel is non-zero but not greater than EXCM level
when load/store instruction is successfully emulated. This allows
single-stepping over such instruction in userspace debugger.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
With this change a threaded jump from .Linvalid_instruction_load to
.Linvalid_instruction can be removed and more code may be added to
common load/store exit path.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
fast_unaligned may encounter DTLB miss or SEGFAULT during the store
emulation. Don't update epc1 and lcount until after the store emulation
is complete, so that the faulting store instruction could be replayed.
Remove duplicate code handling zero overhead loops and calculate new
epc1 and lcount in one place.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
fast_unaligned_fixup restores user registers and runs normal exception
handler in the current stack frame. Unaligned load/store is retried
after that.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Current definition of TLBTEMP_BASE_2 is always 32K above the
TLBTEMP_BASE_1, whereas fast_second_level_miss handler for the TLBTEMP
region analyzes virtual address bit (PAGE_SHIFT + DCACHE_ALIAS_ORDER)
to determine TLBTEMP region where the fault happened. The size of the
TLBTEMP region is also checked incorrectly: not 64K, but twice data
cache way size (whicht may as well be less than the instruction cache
way size).
Fix TLBTEMP_BASE_2 to be TLBTEMP_BASE_1 + data cache way size.
Provide TLBTEMP_SIZE that is a greater of doubled data cache way size or
the instruction cache way size, and use it to determine if the second
level TLB miss occured in the TLBTEMP region.
Practical occurence of page faults in the TLBTEMP area is extremely
rare, this code can be tested by deletion of all w[di]tlb instructions
in the tlbtemp_mapping region.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
With SMP and a lot of debug options enabled task_struct::thread gets out
of reach of s32i/l32i instructions with base pointing at task_struct,
breaking build with the following messages:
arch/xtensa/kernel/entry.S: Assembler messages:
arch/xtensa/kernel/entry.S:1002: Error: operand 3 of 'l32i.n' has invalid value '1048'
arch/xtensa/kernel/entry.S:1831: Error: operand 3 of 's32i.n' has invalid value '1040'
arch/xtensa/kernel/entry.S:1832: Error: operand 3 of 's32i.n' has invalid value '1044'
Change base to point to task_struct::thread in such cases.
Don't use a10 in _switch_to to save/restore prev pointer as a2 is not
clobbered.
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Virtual address is translated to the XCHAL_KSEG_CACHED region in the
dma_free_coherent, but is checked to be in the 0...XCHAL_KSEG_SIZE
range.
Change check for end of the range from 'addr >= X' to 'addr > X - 1' to
handle the case of X == 0.
Replace 'if (C) BUG();' construct with 'BUG_ON(C);'.
Cc: stable@vger.kernel.org
Signed-off-by: Alan Douglas <adouglas@cadence.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Xtensa fixes for 3.16:
- resolve FIXMEs in double exception handler for window overflow. This
fix makes native building of linux on xtensa host possible;
- fix sysmem region removal issue introduced in 3.15.
There are two FIXMEs in the double exception handler 'for the extremely
unlikely case'. This case gets hit by gcc during kernel build once in
a few hours, resulting in an unrecoverable exception condition.
Provide missing fixup routine to handle this case. Double exception
literals now need 8 more bytes, add them to the linker script.
Also replace bbsi instructions with bbsi.l as we're branching depending
on 8th and 7th LSB-based bits of exception address.
This may be tested by adding the explicit DTLB invalidation to window
overflow handlers, like the following:
--- a/arch/xtensa/kernel/vectors.S
+++ b/arch/xtensa/kernel/vectors.S
@@ -592,6 +592,14 @@ ENDPROC(_WindowUnderflow4)
ENTRY_ALIGN64(_WindowOverflow8)
s32e a0, a9, -16
+ bbsi.l a9, 31, 1f
+ rsr a0, ccount
+ bbsi.l a0, 4, 1f
+ pdtlb a0, a9
+ idtlb a0
+ movi a0, 9
+ idtlb a0
+1:
l32e a0, a1, -12
s32e a2, a9, -8
s32e a1, a9, -12
Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop
call in preparation to convert FDT code to use libfdt. Make the return
value const and the property length ptr type an int.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
This option is useful for reserving memory regions for secondary cores
in AMP configurations.
Implement the following memmap variants:
- memmap=nn[KMG]@ss[KMG]: force usage of a specific region of memory;
- memmap=nn[KMG]$ss[KMG]: mark specified memory as reserved;
- memmap=nn[KMG]: set end of memory.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Bootparam meminfo is a bootloader ABI, kernel meminfo is for the kernel
bookkeeping, keep them separate. Kernel doesn't care of memory region
types, so drop the type field and don't pass it to add_sysmem_bank.
Move kernel sysmem structures and prototypes to asm/sysmem.h and sysmem
variable and add_sysmem_bank to mm/init.c
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
