MIPS32R3 introduced a new set of Segmentation Control registers which
increase the flexibility of the segmented-based memory scheme.
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6131/
New Aptiv cores support the TLBINVF instruction for flushing
the VTLB.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6130/
o Move current_cpu_type() to a separate header file
o #ifdefing on supported CPU types lets modern GCC know that certain
code in callers may be discarded ideally turning current_cpu_type() into
a function returning a constant.
o Use current_cpu_type() rather than direct access to struct cpuinfo_mips.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5833/
As Jonas Gorske said in his patch:
Disable cpu_has_mmips for everything but SEAD3 and MALTA. Most of
these platforms are from before the micromips introduction, so they
are very unlikely to implement it.
Reduces an -Os compiled, uncompressed kernel image by 8KiB for
BCM63XX.
This patch taks a different approach than his, we gate the runtime
test for microMIPS by the config symbol SYS_SUPPORTS_MICROMIPS.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5327/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS I is the ancestor of all MIPS ISA and architecture variants. Anything
ever build in the MIPS empire is either MIPS I or at least contains MIPS I.
If it's running Linux, that is.
So there is little point in having cpu_has_mips_1 because it will always
evaluate as true - though usually only at runtime. Thus there is no
point in having the MIPS_CPU_ISA_I ISA flag, so get rid of it.
Little complication: traps.c was using a test for a pure MIPS I ISA as
a test for an R3000-style cp0. To deal with that, use a check for
cpu_has_3kex or cpu_has_4kex instead.
cpu_has_3kex is a new macro. At the moment its default implementation is
!cpu_has_4kex but this may eventually change if Linux is ever going to
support the oddball MIPS processors R6000 and R8000 so users of either
of these macros should not make any assumptions.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5551/
This and the next patch resolve memory corruption problems while CPU
hotplug. Without these patches, memory corruption can triggered easily
as below:
On a quad-core MIPS platform, use "spawn" of UnixBench-5.1.3 (http://
code.google.com/p/byte-unixbench/) and a CPU hotplug script like this
(hotplug.sh):
while true; do
echo 0 >/sys/devices/system/cpu/cpu1/online
echo 0 >/sys/devices/system/cpu/cpu2/online
echo 0 >/sys/devices/system/cpu/cpu3/online
sleep 1
echo 1 >/sys/devices/system/cpu/cpu1/online
echo 1 >/sys/devices/system/cpu/cpu2/online
echo 1 >/sys/devices/system/cpu/cpu3/online
sleep 1
done
Run "hotplug.sh" and then run "spawn 10000", spawn will get segfault
after a few minutes.
This patch:
Currently, clear_page()/copy_page() are generated by Micro-assembler
dynamically. But they are unavailable until uasm_resolve_relocs() has
finished because jump labels are illegal before that. Since these
functions are shared by every CPU, we only call build_clear_page()/
build_copy_page() only once at boot time. Without this patch, programs
will get random memory corruption (segmentation fault, bus error, etc.)
while CPU Hotplug (e.g. one CPU is using clear_page() while another is
generating it in cpu_cache_init()).
For similar reasons we modify build_tlb_refill_handler()'s invocation.
V2:
1, Rework the code to make CPU#0 can be online/offline.
2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU
need a per-CPU tlb_refill_handler().
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongbing Hu <huhb@lemote.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4994/
Acked-by: John Crispin <blogic@openwrt.org>
The presence of the MIPS Virtualization Application-Specific Extension
is indicated by CP0_Config3[23]. Probe for this and report it in
/proc/cpuinfo.
Signed-off-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4904/
Signed-off-by: John Crispin <blogic@openwrt.org>
Display the MIPS ISA version release in the /proc/cpuinfo file.
[ralf@linux-mips.org: Add support for MIPS I ... IV legacy architecture
revisions. Also differenciate between MIPS32 and MIPS64 versions instead
of lumping them together as just r1 and r2.
Note to application programmers: this indicates the CPU's ISA level
It does not imply the current execution environment does support it. For
example an O32 application seeing "mips64r2" would still be restricted by
by the execution environment to 32-bit - but the kernel could run mips64r2
code. The same for a 32-bit kernel running on a 64-bit processor. This
field doesn't include ASEs or optional architecture modules nor other
detailed flags such as the availability of an FPU.]
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/4714/
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>
[ralf@linux-mips.org: This patch really only detects the ASE and passes its
existence on to userland via /proc/cpuinfo. The DSP ASE Rev 2. adds new
resources but no resources that would need management by the kernel.]
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/4165/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The PCI (Program Counter Interrupt) bit in the "cause" register
is mandatory for MIPS32R2 cores, but has also been added to some R1
cores (BMIPS5000). This change adds a cpu feature bit to make it
easier to check for and use this feature.
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/4106/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Remove usage of the 'kernel_uses_smartmips_rixi' macro from all files
and use new 'cpu_has_rixi' instead.
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Acked-by: David Daney <david.daney@cavium.com>
Originally both Read Inhibit (RI) and Execute Inhibit (XI) were
supported by the TLB only for a SmartMIPS core. The MIPSr3(TM)
Architecture now defines an optional feature to implement these
TLB bits separately. Support for one or both features can be
checked by looking at the Config3.RXI bit.
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Acked-by: David Daney <david.daney@cavium.com>
The SmartMIPS ASE specifies how Read Inhibit (RI) and eXecute Inhibit
(XI) bits in the page tables work. The upper two bits of EntryLo{0,1}
are RI and XI when the feature is enabled in the PageGrain register.
SmartMIPS only covers 32-bit systems. Cavium Octeon+ extends this to
64-bit systems by continuing to place the RI and XI bits in the top of
EntryLo even when EntryLo is 64-bits wide.
Because we need to carry the RI and XI bits in the PTE, the layout of
the PTE is changed. There is a two instruction overhead in the TLB
refill hot path to get the EntryLo bits into the proper position.
Also the TLB load exception has to probe the TLB to check if RI or XI
caused the exception.
Also of note is that the layout of the PTE bits is done at compile and
runtime rather than statically. In the 32-bit case this allows for
the same number of PFN bits as before the patch as the _PAGE_HUGE is
not supported in 32-bit kernels (we have _PAGE_NO_EXEC and
_PAGE_NO_READ instead of _PAGE_READ and _PAGE_HUGE).
The patch is tested on Cavium Octeon+, but should also work on 32-bit
systems with the Smart-MIPS ASE.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/952/
Patchwork: http://patchwork.linux-mips.org/patch/956/
Patchwork: http://patchwork.linux-mips.org/patch/962/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Linux kernel 2.6.32 and later allocate address space from the top of the
kernel virtual memory address space.
This patch implements virtual memory size detection for 64 bit MIPS CPUs
to avoid resulting crashes.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/935/
Reviewed-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
On some CPUs, it is more efficient to disable and enable interrupts in the
kernel rather than use ll/sc for atomic operations. But if we were to set
cpu_has_llsc to false, we would break the userspace futex interface (in
asm/futex.h).
We separate the two concepts, with a new predicate kernel_uses_llsc, that
lets us disable the kernel's use of ll/sc while still allowing the futex
code to use it.
Also there were a couple of cases in bitops.h where we were using ll/sc
unconditionally even if cpu_has_llsc were false.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some CPUs have implementation dependent rdhwr registers. Allow them
to be enabled on a per CPU basis.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some CPUs do not need ehb instructions after writing CP0 registers.
By allowing ehb generation to be overridden in
cpu-feature-overrides.h, we can save a few instructions in the TLB
handler hot paths.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is useful for IDT RC32332, RC32334 and NEC VR5500 processors which do
not implement the full MIPS32 / MIPS64 architecture.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Follow precedent of other boards, and hook-up the CPU specific cache
init.
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>
Steven J. Hill