This patch adds support for context switching the MSA vector registers.
These 128 bit vector registers are aliased with the FP registers - an
FP register accesses the least significant bits of the vector register
with which it is aliased (ie. the register with the same index). Due to
both this & the requirement that the scalar FPU must be 64-bit (FR=1) if
enabled at the same time as MSA the kernel will enable MSA & scalar FP
at the same time for tasks which use MSA. If we restore the MSA vector
context then we might as well enable the scalar FPU since the reason it
was left disabled was to allow for lazy FP context restoring - but we
just restored the FP context as it's a subset of the vector context. If
we restore the FP context and have previously used MSA then we have to
restore the whole vector context anyway (see comment in
enable_restore_fp_context for details) so similarly we might as well
enable MSA.
Thus if a task does not use MSA then it will continue to behave as
without this patch - the scalar FP context will be saved & restored as
usual. But if a task executes an MSA instruction then it will save &
restore the vector context forever more.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6431/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The hard-coded offsets mentioned in this comment seem to not exist
anymore, so remove mention of them from the comment.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6421/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch replaces the fpureg_t typedef with a "union fpureg" enabling
easier access to 32 & 64 bit values. This allows the access macros used
in cp1emu.c to be simplified somewhat. It will also make it easier to
expand the width of the FP registers as will be done in a future
patch in order to support the 128 bit registers introduced with MSA.
No behavioural change is intended by this patch.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6532/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add COP2 register state structure and functions for Netlogic XLP. The
RX and TX buffers and status registers are to be saved. Since the
registers are 64-bit, do the implementation in inline assembly which
works on both 32-bit and 64-bit kernels.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Cc: ddaney.cavm@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/5413/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move the common code for saving and restoring platform specific COP2
registers to switch_to(). This will make supporting new platforms (like
Netlogic XLP) easier.
The platform specific COP2 definitions are to be specified in
asm/processor.h and in asm/cop2.h.
Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Cc: ddaney.cavm@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/5411/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"The MIPS bits for 3.8. This also includes a bunch fixes that were
sitting in the linux-mips.org git tree for a long time. This pull
request contains updates to several OCTEON drivers and the board
support code for BCM47XX, BCM63XX, XLP, XLR, XLS, lantiq, Loongson1B,
updates to the SSB bus support, MIPS kexec code and adds support for
kdump.
When pulling this, there are two expected merge conflicts in
include/linux/bcma/bcma_driver_chipcommon.h which are trivial to
resolve, just remove the conflict markers and keep both alternatives."
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (90 commits)
MIPS: PMC-Sierra Yosemite: Remove support.
VIDEO: Newport Fix console crashes
MIPS: wrppmc: Fix build of PCI code.
MIPS: IP22/IP28: Fix build of EISA code.
MIPS: RB532: Fix build of prom code.
MIPS: PowerTV: Fix build.
MIPS: IP27: Correct fucked grammar in ops-bridge.c
MIPS: Highmem: Fix build error if CONFIG_DEBUG_HIGHMEM is disabled
MIPS: Fix potencial corruption
MIPS: Fix for warning from FPU emulation code
MIPS: Handle COP3 Unusable exception as COP1X for FP emulation
MIPS: Fix poweroff failure when HOTPLUG_CPU configured.
MIPS: MT: Fix build with CONFIG_UIDGID_STRICT_TYPE_CHECKS=y
MIPS: Remove unused smvp.h
MIPS/EDAC: Improve OCTEON EDAC support.
MIPS: OCTEON: Add definitions for OCTEON memory contoller registers.
MIPS: OCTEON: Add OCTEON family definitions to octeon-model.h
ata: pata_octeon_cf: Use correct byte order for DMA in when built little-endian.
MIPS/OCTEON/ata: Convert pata_octeon_cf.c to use device tree.
MIPS: Remove usage of CEVT_R4K_LIB config option.
...
2957c9e61e (kernel.org) rsp.
b934da913f236bca00c41d9e386e980586000461 (lmo) [[MIPS] IRIX: Goodbye and
thanks for all the fish] left two fields in struct thread_struct which
were only being used for the IRIX compat code. Remove them.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.
Remove it and use the arch_dup_task_struct() instead.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The TASK_SIZE macro should reflect the size of a user process virtual
address space. Previously for 64-bit kernels, this was not the case.
The immediate cause of pain was in
hugetlbfs/inode.c:hugetlb_get_unmapped_area() where 32-bit processes
trying to mmap a huge page would be served a page with an address
outside of the 32-bit address range. But there are other uses of
TASK_SIZE in the kernel as well that would like an accurate value.
The new definition is nice because it now makes TASK_SIZE and
TASK_SIZE_OF() yield the same value for any given process.
For 32-bit kernels there should be no change, although I did factor
out some code in asm/processor.h that became identical for the 32-bit and
64-bit cases.
__UA_LIMIT is now set to ~((1 << SEGBITS) - 1) for 64-bit kernels.
This should eliminate the possibility of getting a
AddressErrorException in the kernel for addresses that pass the
access_ok() test.
With the patch applied, I can still run o32, n32 and n64 processes,
and have an o32 shell fork/exec both n32 and n64 processes.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1701/
Fairly straight forward: For 32-bit address spaces randomize within a
16MB space, for 64-bit within a 256MB space.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1480/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
GCC's __builtin_prefetch() was introduced a long time ago, all
supported GCC versions have it. Lets do what the big boys up in
linux/prefetch.h do, except we use '1' as the third parameter to
provoke 'PREF 0,...' and 'PREF 1,...' instead of other prefetch
hints.
This allows for better code generation. In theory the existing
embedded asm could be optimized, but the compiler has these builtins,
so there is really no point.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1235/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is a preliminary patch to add a vdso to all user processes. Still
missing are ELF headers and .eh_frame information. But it is enough to
allow us to move signal trampolines off of the stack. Note that emulation
of branch delay slots in the FPU emulator still requires the stack.
We allocate a single page (the vdso) and write all possible signal
trampolines into it. The stack is moved down by one page and the vdso is
mapped into this space.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/975/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The resume() implementation octeon_switch.S examines the saved cp0_status
register. We were clobbering the entire pt_regs structure in kernel
threads leading to random crashes.
When switching away from a kernel thread, the saved cp0_status is examined
and if bit 30 is set it is cleared and the CP2 state saved into the pt_regs
structure. Since the kernel thread stack overlaid the pt_regs structure
this resulted in a corrupt stack. When the kthread with the corrupt stack
was resumed, it could crash if it used any of the data in the stack that was
clobbered.
We fix it by moving the kernel thread stack down so it doesn't overlay
pt_regs.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add in the cop2 and cvmseg state info to the known proc reg
data for Cavium so that it can be tracked, saved, restored.
Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com>
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is the main support code for the patch. Here we just add the
code, the following patches hook it up.
Signed-off-by: David Daney <ddaney@avtrex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
create mode 100644 arch/mips/include/asm/watch.h
create mode 100644 arch/mips/kernel/watch.c
Paul Burton