__clear_user() (and clear_user() which uses it), always access the user
mode address space, which results in EVA store instructions when EVA is
enabled even if the current user address limit is KERNEL_DS.
Fix this by adding a new symbol __bzero_kernel for the normal kernel
address space bzero in EVA mode, and call that from __clear_user() if
eva_kernel_access().
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10844/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS R6 dropped the unaligned load and store instructions so
we need to re-write this part of the code for R6 to store
one byte at a time.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
The toolchain defines exactly one of __MIPSEB__ and
__MIPSEL__. As a result, simplify the ifdefery a little bit.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8522/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Build the __bzero function using the EVA load/store instructions
when operating in the EVA mode. This function is only used when
accessing user code so there is no need to build two distinct symbols
for user and kernel operations respectively.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Build the __bzero symbol using a macor. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Optimise 'memset' to use microMIPS instructions and/or optimisations
for binary size reduction. When the microMIPS ISA is not being used,
the library function compiles to the original binary code.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
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>
partial_fixup is used in noreorder block.
Separating two consecutive loads can save one cycle on processors with
GPR intrelock and can fix load-use on processors that need a load delay slot.
Also do so for fwd_fixup.
[Ralf: Only R2000/R3000 class processors are lacking the the load-user
interlock and even some of those got it retrofitted. With R2000/R3000
being fairly uncommon these days the impact of this bug should be minor.]
Signed-off-by: Tony Wu <tung7970@gmail.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1768/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
These symbols appear in oprofile output, stacktraces and similar but only
make the output harder to read. Many identical symbol names such as
"both_aligned" were also being used in multiple source files making it
impossible to see which file actually was meant. So let's get rid of them.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
IP28 needs special treatment to avoid speculative accesses. gcc
takes care for .c code, but for assembly code we need to do it
manually.
This is taken from Peter Fuersts IP28 patches.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This complements the generic R4000/R4400 errata workaround code and adds
bits for the daddiu problem. In most places it just modifies handwritten
assembly code so that the assembler is allowed to use a temporary register
as daddiu may now be treated as a macro that expands to a sequence of li
and daddu. It is the AT register or, where AT is unavailable or used
explicitly for another purpose, an explicitly-named register is selected,
using the .set at=<reg> feature added recently to gas. This feature is
only used if CONFIG_CPU_DADDI_WORKAROUNDS has been set, so if the
workaround remains disabled, the required version of binutils stays
unchanged.
Similarly, daddiu instructions put in branch delay slots in noreorder
fragments are now taken out of them and the assembler is allowed to
reorder them itself as possible (which it does making the whole idea of
scheduling them into delay slots manually questionable).
Also in the very few places where such a simple conversion was not
possible, a handcoded longer sequence is implemented.
Other than that there are changes to code responsible for building the
TLB fault and page clear/copy handlers to avoid daddiu as appropriate.
These are only effective if the erratum is verified to be present at the
run time.
Finally there is a trivial update to __delay(), because it uses daddiu in
a branch delay slot.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The 32-bit version and 64-bit version are almost equal. Unify them.
This makes further improvements (for example, supporting CDEX, etc.)
easier.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
