Loongson 1B is a 32-bit SoC designed by Institute of Computing Technology
(ICT) and the Chinese Academy of Sciences (CAS), which implements the
MIPS32 release 2 instruction set.

[ralf@linux-mips.org: But which is not strictly a MIPS32 compliant device
which also is why it identifies itself with the Legacy Vendor ID in the
PrID register.  When applying the patch I shoveled some code around to
keep things in alphabetical order and avoid forward declarations.]
Signed-off-by: NKelvin Cheung <keguang.zhang@gmail.com>
Cc: To: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: wuzhangjin@gmail.com
Cc: zhzhl555@gmail.com
Cc: Kelvin Cheung <keguang.zhang@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3976/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When building oprofile as a module for R10000 or R7000 class processors,
E9000 or MIPSxx class cores since 3572a2c3
[MIPS: make oprofile use cp0_perfcount_irq if it is set] an

ERROR: "cp0_compare_irq" [arch/mips/oprofile/oprofile.ko] undefined!

error will happen.  Fixed by exporting cp0_compare_irq.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

show_backtrace() was passed a NULL pointer which caused paging
request fail. Set to current task as other architectures (ARM,
etc) do when passed a NULL task pointer.
Signed-off-by: NVincent Wen <vincentwenlinux@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/3524/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

It's a bloody bog standard MIPS64R2 core with just a new PrId ID.  Iow
that essentially means Linux just panics because it doesn't know how to
name the core.

[ralf@linux-mips.org: Split original patch into several smaller patches.]
Signed-off-by: NLeonid Yegoshin <yegoshin@mips.com>
Signed-off-by: NSteven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3792/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Based on https://patchwork.linux-mips.org/patch/3576 - but this really
deserves its own patchset and the symbol should also be used :)
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

commit 97ce2c88 (jump-label: initialize
jump-label subsystem much earlier) breaks MIPS.  The jump_label_init()
call was moved before trap_init() which is where we initialize
flush_icache_range().

In order to be good citizens, we move cache initialization earlier so
that we don't jump through a null flush_icache_range function pointer
when doing the jump label initialization.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3822/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Follow-on patches require this.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3818/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This is used in subsequent patches.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3819/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

These will show up as a build failure once we clean up a
misuse of module.h in the mips termios header.

Uses export.h: (EXPORT_SYMBOL)
   arch/mips/cavium-octeon/setup.c
   arch/mips/pmc-sierra/yosemite/setup.c
   arch/mips/rb532/devices.c
   arch/mips/sni/setup.c

Uses module.h: (symbol_get/put)
   arch/mips/alchemy/devboards/db1200.c

Uses module.h: (print_modules)
   arch/mips/kernel/traps.c
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3448/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Disintegrate asm/system.h for MIPS.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
cc: linux-mips@linux-mips.org

Correct spelling of "Schedulier" to "Scheduler" in arch/mips/kernel/traps.c
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/3354/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Use the more commonly used __noreturn instead of ATTRIB_NORETURN.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It's a very old and now unused prototype marking so just delete it.

Neaten panic pointer argument style to keep checkpatch quiet.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some systems need to relocate the MIPS exception vector base during
trap initialization.  Add a hook to make this possible.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2959/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Allow the board support code to register a raw notifier callback for
NMI, similar to what is done for CU2 exceptions.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2958/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Panic() invokes printk() to add a \n internally, so panic arguments should
not themselves end in \n.  Panic invocations in arch/mips and elsewhere
are inconsistently sometimes terminating in \n, sometimes not.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

I am running SMP Linux 2.6.37-rc1 on BMIPS5000 (single core dual thread)
and observe some abnormalities when doing system suspend/resume which I
narrowed down to cpu hotplugging. The suspend brings the second thread
processor down and then restarts it, after which I see memory corruption
in userspace. I started digging and found out that problem occurs because
while doing execve() the child process is getting the same ASID as the
parent, which obviously corrupts parent's address space.

Further digging showed that activate_mm() calls get_new_mmu_context() to
get a new ASID, but at this time ASID field in entryHi is 1, and
asid_cache(cpu) is 0x100 (it was just reset to ASID_FIRST_VERSION when
the secondary TP was booting).

So, get_new_mmu_context() increments the asid_cache(cpu) value to
0x101, and thus puts 0x01 into entryHi. The result - ASID field does
not get changed as it was supposed to.

My solution is very simple - do not reset asid_cache(cpu) on TP warm
restart.

Patchwork: https://patchwork.linux-mips.org/patch/1797/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

None of these files are using modular infrastructure, and build
tests reveal that none of these files are really relying on any
implicit inclusions via. module.h either.  So delete them.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

This allows pause_on_oops and mtdoops to work.
Signed-off-by: NNathan Lynch <ntl@pobox.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2810/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

On preempt-rt this lock needs to be raw, so it does not get converted
to a sleeping spinlock. Trying to sleep in a panic is not really
desireable.
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2636/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.

For the various event classes:

  - hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
    the PMI-tail (ARM etc.)
  - tracepoint: nmi=0; since tracepoint could be from NMI context.
  - software: nmi=[0,1]; some, like the schedule thing cannot
    perform wakeups, and hence need 0.

As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).

The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>

Initial patch by Yury Polyanskiy <ypolyans@princeton.edu>.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/2373/

Decide at runtime to use either Context or KScratch to hold the PGD
pointer.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1876/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We were unconditionally sending SIGBUS with an empty siginfo on FP
emulator faults.  This differs from what happens when real floating
point hardware would get a fault.

For most faults we need to send SIGSEGV with the faulting address
filled in in the struct siginfo.
Reported-by: NCamm Maguire <camm@maguirefamily.org>
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Camm Maguire <camm@maguirefamily.org>
Patchwork: https://patchwork.linux-mips.org/patch/1727/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Some MIPS32R1 processors implement UserLocal (RDHWR $29) to accelerate
programs that make extensive use of thread-local storage.  Therefore,
setting up the HWRENA register should not depend on cpu_has_mips_r2.
Signed-off-by: NKevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org

Software events are required as part of the measurable stuff by the
Linux performance counter subsystem. Here is the list of events added by
this patch:
PERF_COUNT_SW_PAGE_FAULTS
PERF_COUNT_SW_PAGE_FAULTS_MIN
PERF_COUNT_SW_PAGE_FAULTS_MAJ
PERF_COUNT_SW_ALIGNMENT_FAULTS
PERF_COUNT_SW_EMULATION_FAULTS
Signed-off-by: NDeng-Cheng Zhu <dengcheng.zhu@gmail.com>
To: linux-mips@linux-mips.org
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@elte.hu
Cc: acme@redhat.com
Cc: jamie.iles@picochip.com
Acked-by: NDavid Daney <ddaney@caviumnetworks.com>
Reviewed-by: NMatt Fleming <matt@console-pimps.org>
Patchwork: https://patchwork.linux-mips.org/patch/1686/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add missing #inclusions of <linux/irq.h> to a whole bunch of files that should
really include it.  Note that this can replace #inclusions of <asm/irq.h>.

This is required for the patch to sort out irqflags handling function naming to
compile on MIPS.

The problem is that these files require access to things like setup_irq() -
which isn't available by #including <linux/interrupt.h>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>

The sixth argument of notify_die() is a signal number, the fifth is a
trap number.

Instead of passing a signal number in a randomly selected argument,
pass it in the sixth.  Extract the exception code from regs and pass
that as the trap number.

Get rid of redundant cast, and remove some gratuitous spaces.

Nobody actually does anything with the signal number or trap number,
but we might as well populate them with sensible values.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1532/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

It is initialized to zero and only ever read.  Remove it, and pass zero in
its place.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1531/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch is based on previous work by Sony and Himanshu Chauhan.

I have done some cleanup and implemented JProbes and KRETPROBES.  The
KRETPROBES part is pretty much copied verbatim from powerpc.  A possible
future enhance might be to factor out the common code.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Cc: Himanshu Chauhan <hschauhan@nulltrace.org>
To: linux-mips@linux-mips.org
To: ananth@in.ibm.com,
To: anil.s.keshavamurthy@intel.com
To: davem@davemloft.net
To: masami.hiramatsu.pt@hitachi.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1525/
Patchwork: https://patchwork.linux-mips.org/patch/1530/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Patchwork: https://patchwork.linux-mips.org/patch/1504/

Breaking here dropped us to the default code which always sends a SIGILL
to the current process, no matter what the CU2 notifier says.

[Ralf: Currently this only hurts on Cavium and possibly some out of tree
platforms.]
Signed-off-by: NJesper Nilsson <jesper@jni.nu>
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
Patchwork: http://patchwork.linux-mips.org/patch/1391/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

From: Julia Lawall <julia@diku.dk>

Use set_cpus_allowed_ptr rather than set_cpus_allowed.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E1,E2;
@@

- set_cpus_allowed(E1, cpumask_of_cpu(E2))
+ set_cpus_allowed_ptr(E1, cpumask_of(E2))

@@
expression E;
identifier I;
@@

- set_cpus_allowed(E, I)
+ set_cpus_allowed_ptr(E, &I)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
To: peterz@infradead.org
To: mingo@elte.hu
To: tglx@linutronix.de
To: oleg@redhat.com
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
To: kernel-janitors@vger.kernel.org
Patchwork: http://patchwork.linux-mips.org/patch/1087/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" do_trap_or_bp() handler.

Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.

Also added was a die notification for oops such that kdb can catch an
oops for analysis.

There appeared to be no obvious way to pass the struct pt_regs from
the original exception back to the stack back tracer, so a special
case was added to show_stack() for when kdb is active because you
generally desire to generally look at the back trace of the original
exception.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>

"MIPS: Calculate proper ebase value for 64-bit kernels"
9af43ea080dd5d6c7b34f38261780e5dd43537bc (lmo) rsp.
f6be75d0 (kernel.org) broke some 64-bit
MIPS systems.

Before this we were using XKPHYS/cached as ebase and computed the uncached
xphsys/unchached address for that area. After that commit ebase became a
32-bit compat address and convert does not work anymore.  We now should use
CKSEG1 for this. CKSEG1ADDR does just that in 32-bit and 64-bit.
Signed-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
To: Ralf Baechle <ralf@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1149/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The MIPS implementation of die() forgets to call notify_die() and thus notifiers
registered via register_die_notifier() are not called.  This results in kgdb not
being activated on exceptions.

The only subtlety is that notify_die declares its regs argument w/o const, so
the const had to be removed from mips die() as well.

[Ralf: Fixed build error for SGI IP22 and IP28 platforms.]
Signed-off-by: NYury Polyanskiy <ypolyans@princeton.edu>
Cc: linux-mips@linux-mips.org
Patchworks: http://patchwork.linux-mips.org/patch/1142/Acked-by: NJason Wessel <jason.wessel@windriver.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

---

The ebase is relative to CKSEG0 not CAC_BASE.  On a 32-bit kernel they
are the same thing, for a 64-bit kernel they are not.

It happens to kind of work on a 64-bit kernel as they both reference
the same physical memory.  However since the CPU uses the CKSEG0 base,
determining if a J instruction will reach always gives the wrong result
unless we use the same number the CPU uses.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1093/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

AR7 has a larger physical offset than other MIPS based systems and therefore
needs to setup its handlers beyond the usual KSEG0 range. When running the
kernel in mapped mode this modification is also required. Remove function
comment which is now incorrect.
Signed-off-by: NDavid Daney <ddaney@caviumnetworks.com>
Signed-off-by: NEugene Konev <ejka@imfi.kspu.ru>
Signed-off-by: NFlorian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/889/
Patchwork: http://patchwork.linux-mips.org/patch/932/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

All call sites of set_except_vector are already annotated with __init, so
annotate that one too.
Signed-off-by: NRegards, Florian Fainelli <florian@openwrt.org>
To: linux-mips@linux-mips.org
To: David Daney <ddaney@caviumnetworks.com>
Patchwork: http://patchwork.linux-mips.org/patch/888/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

As reported by Maxime Bizon, the commit "MIPS: PowerTV: Fix support for
timer interrupts with > 64 external IRQs" have broken the r4k timer
since it didn't initialize the cp0_compare_irq_shift variable used in
c0_compare_int_pending() on the architectures whose cpu_has_mips_r2 is
false.

This patch fixes it via initializing the cp0_compare_irq_shift as the
cp0_compare_irq used in the old c0_compare_int_pending().
Reported-by: NMaxime Bizon <mbizon@freebox.fr>
Signed-off-by: NWu Zhangjin <wuzhangjin@gmail.com>
Cc: David VomLehn <dvomlehn@cisco.com>
Cc: mbizon@freebox.fr
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/922/Tested-by: NShane McDonald <mcdonald.shane@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>