Our FP emulator is hardcoded for the MIPS IV FP instruction set and does
not match the FP ISA with the general ISA. However for the few MIPS IV FP
instructions that use the COP1X major opcode it relies on the Coprocessor
Unusable exception to be delivered as a COP1 rather than COP3 exception.
This includes indexed transfer (LDXC1, etc.) and FP multiply-accumulate
(MADD.D, etc.) instructions.
All the MIPS I, II, III and IV processors and some newer chips that do not
implement the FPU use the COP3 exception however. Therefore I believe the
kernel should follow and redirect any COP3 Unusable traps to the emulator
unless an actual FPU part or core is present.
This is a change that implements it. Any minor opcode encodings that are
not recognised as valid FP instructions are rejected by the emulator and
will result in a SIGILL signal being delivered as they currently do. We
do not support vendor-specific coprocessor 3 implementations supported
with MIPS I and MIPS II ISA processors; we never set CP0.Status.CU3.
[Ralf: On MIPS IV processors the kernel always enables the XX bit which
replaces the CU3 bit off earlier architecture revisions.]
If matching between the CPU and the FPU ISA is considered required one
day, this can still be done in the emulator itself. I think the CpU
exception dispatcher is not the right place to do this anyway, as there
are further differences between MIPS I, MIPS II, MIPS III, MIPS IV and
MIPS32 FP ISAs.
Corresponding explanation of this implementation is included within the
change itself.
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/project/linux-mips/list/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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: Kelvin 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: Ralf Baechle <ralf@linux-mips.org>
When building oprofile as a module for R10000 or R7000 class processors,
E9000 or MIPSxx class cores since 3572a2c37f
[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: Ralf 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: Vincent 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: Ralf 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: Leonid Yegoshin <yegoshin@mips.com>
Signed-off-by: Steven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3792/
Signed-off-by: Ralf 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: Ralf Baechle <ralf@linux-mips.org>
commit 97ce2c88f9 (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: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3822/
Signed-off-by: Ralf 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: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3448/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some systems need to relocate the MIPS exception vector base during
trap initialization. Add a hook to make this possible.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2959/
Signed-off-by: Ralf 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: Kevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2958/
Signed-off-by: Ralf 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: Ralf 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: Ralf 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: Paul Gortmaker <paul.gortmaker@windriver.com>
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: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2636/
Signed-off-by: Ralf 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: Peter 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.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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: Camm Maguire <camm@maguirefamily.org>
Signed-off-by: David 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: Ralf 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: Kevin 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: Deng-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: David Daney <ddaney@caviumnetworks.com>
Reviewed-by: Matt Fleming <matt@console-pimps.org>
Patchwork: https://patchwork.linux-mips.org/patch/1686/
Signed-off-by: Ralf 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: David Howells <dhowells@redhat.com>
Acked-by: Ralf 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: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1532/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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: Jesper 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: Ralf 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: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
"MIPS: Calculate proper ebase value for 64-bit kernels"
9af43ea080dd5d6c7b34f38261780e5dd43537bc (lmo) rsp.
f6be75d03c (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: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
To: Ralf Baechle <ralf@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1149/
Signed-off-by: Ralf 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: Yury Polyanskiy <ypolyans@princeton.edu>
Cc: linux-mips@linux-mips.org
Patchworks: http://patchwork.linux-mips.org/patch/1142/
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ralf 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: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1093/
Signed-off-by: Ralf 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: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Eugene Konev <ejka@imfi.kspu.ru>
Signed-off-by: Florian 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: Ralf 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: Regards, 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: Ralf 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: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Wu 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: Shane McDonald <mcdonald.shane@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The MIPS processor is limited to 64 external interrupt sources. Using a
greater number without IRQ sharing requires reading platform-specific
registers. On such platforms, reading the IntCtl register to determine
which interrupt corresponds to a timer interrupt will not work.
On MIPSR2 systems there is a solution - the TI bit in the Cause register,
specifically indicates that a timer interrupt has occured. This patch uses
that bit to detect interrupts for MIPSR2 processors, which may be expected
to work regardless of how the timer interrupt may be routed in the hardware.
Signed-off-by: David VomLehn (dvomlehn@cisco.com)
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/804/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Away with the daemons of ifdef; get ready for future COP2 users.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/708/
Maciej W. Rozycki
Ralf Baechle
Kelvin Cheung
Vincent Wen
Leonid Yegoshin
David Daney
Paul Gortmaker
David Howells
Masanari Iida
Linus Torvalds
Joe Perches
Kevin Cernekee
Maksim Rayskiy
Nathan Lynch
Wu Zhangjin
Peter Zijlstra
David Daney
Deng-Cheng Zhu
Jesper Nilsson
Julia Lawall
Jason Wessel
Sebastian Andrzej Siewior
Yury Polyanskiy
Florian Fainelli
David VomLehn