The following instructions have been removed from MIPS R6
ulw, ulh, swl, lwr, lwl, swr.
However, all of them are used in the MIPS specific checksum implementation.
As a result of which, we will use the generic checksum on MIPS R6
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
The HI/LO registers have been removed from MIPS R6. Instructions
such as MULT and DIV have been replaced with a new pair of
instructions for the HI/LO operations for example:
MULT -> MUL, MUH
DIV -> DIV, MOD
So we avoid preserving the pre-R6 HI/LO registers in MIPS R6
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
There are certain places where the code uses .set mips32 or .set mips64
or .set arch=r4000. In preparation of MIPS R6 support, and in order to
use as less #ifdefs as possible, we define new macros to set similar
annotations for MIPS R6.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS R6 defines new opcodes for ll, sc, cache and pref instructions
so we need to take these into consideration in the micro-assembler.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS R6 redefines several instructions and reduces the immediate
field to 9-bits so add related macros for the microassembler.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Latest versions of QEMU added support for mips32r6-generic and
mips64r6-generic cpu types so add related definitions in preparation
of MIPS R6 support. This is also used for QEMU R2 generic cpus.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
activate_mm() and switch_mm() call get_new_mmu_context() which in turn
can enable the HTW before the entryhi is changed with the new ASID.
Since the latter will enable the HTW in local_flush_tlb_all(),
then there is a small timing window where the HTW is running with the
new ASID but with an old pgd since the TLBMISS_HANDLER_SETUP_PGD
hasn't assigned a new one yet. In order to prevent that, we introduce a
simple htw counter to avoid starting HTW accidentally due to nested
htw_{start,stop}() sequences. Moreover, since various IPI calls can
enforce TLB flushing operations on a different core, such an operation
may interrupt another htw_{stop,start} in progress leading inconsistent
updates of the htw_seq variable. In order to avoid that, we disable the
interrupts whenever we update that variable.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9118/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Whenever we modify a page table entry, we need to ensure that the HTW
will not fetch a stable entry. And for that to happen we need to ensure
that HTW is stopped before we modify the said entry otherwise the HTW
may already be in the process of reading that entry and fetching the
old information. As a result of which, we replace the htw_reset() calls
with htw_{stop,start} in more appropriate places. This also removes the
remaining users of htw_reset() and as a result we drop that macro
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.17+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9116/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 41c594ab65 ("[MIPS] MT: Improved multithreading support.")
removed useful debug information for userland segmentation faults.
This patch bring this back along with the ability to determine the
name of the object file where the EPC and RA registers point at.
Furthermore, we select the SYSCTL_EXCEPTION_TRACE symbol for MIPS
which is the de facto solution to turn userland exception logging
on and off via the /proc/sys/debug/exception-trace file.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9089/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Userland code may be built using an ABI which permits linking to objects
that have more restrictive floating point requirements. For example,
userland code may be built to target the O32 FPXX ABI. Such code may be
linked with other FPXX code, or code built for either one of the more
restrictive FP32 or FP64. When linking with more restrictive code, the
overall requirement of the process becomes that of the more restrictive
code. The kernel has no way to know in advance which mode the process
will need to be executed in, and indeed it may need to change during
execution. The dynamic loader is the only code which will know the
overall required mode, and so it needs to have a means to instruct the
kernel to switch the FP mode of the process.
This patch introduces 2 new options to the prctl syscall which provide
such a capability. The FP mode of the process is represented as a
simple bitmask combining a number of mode bits mirroring those present
in the hardware. Userland can either retrieve the current FP mode of
the process:
mode = prctl(PR_GET_FP_MODE);
or modify the current FP mode of the process:
err = prctl(PR_SET_FP_MODE, new_mode);
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8899/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The cevt-r4k driver used to call into the GIC driver to find whether the
timer was pending, but only with External Interrupt Controller (EIC)
mode, where the Cause.IP bits can't be used as they encode the interrupt
priority level (Cause.RIPL) instead.
However commit e9de688dac ("irqchip: mips-gic: Support local
interrupts") changed the condition from cpu_has_veic to gic_present.
This fails on cores such as P5600 which have a GIC but the local
interrupts aren't routable by the GIC, causing c0_compare_int_usable()
to consider the interrupt unusable so r4k_clockevent_init() fails.
The previous behaviour, added in commit 98b67c37db ("MIPS: Add EIC
support for GIC."), wasn't really correct either as far as I can tell,
since P5600 apparently supports EIC mode too, and in any case the use of
Cause.TI with r2 should have been sufficient anyway since commit
010c108d7a ("MIPS: PowerTV: Fix support for timer interrupts with > 64
external IRQs").
Therefore drop the call into the gic driver altogether, and add a
comment in c0_compare_int_pending() to clarify that Cause.TI does get
checked since MIPS r2.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Fixes: e9de688dac ("irqchip: mips-gic: Support local interrupts")
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <steven.hill@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9077/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
HOSTCC arch/mips/boot/elf2ecoff
arch/mips/boot/elf2ecoff.c: In function ‘main’:
arch/mips/boot/elf2ecoff.c:271:8: warning: variable ‘shstrtab’ set but not used [-Wunused-but-set-variable]
char *shstrtab;
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some instances of pci_ops initialization rely on the read/write members'
location in the struct. This is fragile and may break when adding new
members to the beginning of the struct.
[ralf@linux-mips.org: indent = with tabs for consistency.]
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Patchwork: https://patchwork.linux-mips.org/patch/8915/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Markos Chandras
Leonid Yegoshin
Paul Burton
James Hogan
Ralf Baechle
Rob Herring
Geert Uytterhoeven