The nomips16 has to be added both as function attribute and assembler
directive.
When only function attribute is specified, the compiler will inline the
function with -Os optimization. The generated assembly code cannot be
correctly assembled because ISA mode switch has to be done through jump
instruction.
When only ".set nomips16" directive is used, the generated assembly code
will use MIPS32 code for the inline assembly template and MIPS16 for the
function return. The compiled binary is invalid:
00403100 <__arch_swab16>:
403100: 7c0410a0 wsbh v0,a0
403104: e820ea31 swc2 $0,-5583(at)
while correct code should be:
00402650 <__arch_swab16>:
402650: 7c0410a0 wsbh v0,a0
402654: 03e00008 jr ra
402658: 3042ffff andi v0,v0,0xffff
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
Cc: Chen Jie <chenj@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11087/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The context introduced by MSA needs to be saved around signals. However,
we can't increase the size of struct sigcontext because that will change
the offset of the signal mask in struct sigframe or struct ucontext.
This patch instead places the new context immediately after the struct
sigframe for traditional signals, or similarly after struct ucontext for
RT signals. The layout of struct sigframe & struct ucontext is identical
from their sigcontext fields onwards, so the offset from the sigcontext
to the extended context will always be the same regardless of the type
of signal.
Userland will be able to search through the extended context by using
the magic values to detect which types of context are present. Any
unrecognised context can be skipped over using the size field of struct
extcontext. Once the magic value END_EXTCONTEXT_MAGIC is seen it is
known that there are no further extended context structures to examine.
This approach is somewhat similar to that taken by ARM to save VFP &
other context at the end of struct ucontext.
Userland can determine whether extended context is present by checking
for the USED_EXTCONTEXT bit in the sc_used_math field of struct
sigcontext. Whilst this could potentially change the historic semantics
of sc_used_math if further extended context which does not imply FP
context were to be introduced in the future, I have been unable to find
any userland code making use of sc_used_math at all. Using one of the
fields described as unused in struct sigcontext was considered, but the
kernel does not already write to those fields so there would be no
guarantee of the field being clear on older kernels. Other alternatives
would be to have userland check the kernel version, or to have a HWCAP
bit indicating presence of extended context. However there is a desire
to have the context & information required to decode it be self
contained such that, for example, debuggers could decode the saved
context easily.
[ralf@linux-mips.org: Fixed conflict.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: linux-kernel@vger.kernel.org
Cc: Richard Weinberger <richard@nod.at>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Maciej W. Rozycki <macro@codesourcery.com>
Patchwork: https://patchwork.linux-mips.org/patch/10795/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The sc_used_math field of struct sigcontext & its variants has
traditionally been used as a boolean value indicating only whether or
not floating point context is saved within the sigcontext. With various
supported FP modes & the ability to switch between them this information
will no longer be enough to decode the meaning of the data stored in the
sc_fpregs fields of struct sigcontext.
To make that possible 3 bits are defined within sc_used_math:
- Bit 0 (USED_FP) represents whether FP was used, essentially
providing the boolean flag which sc_used_math as a whole provided
previously.
- Bit 1 (USED_FR1) provides the value of the Status.FR bit at the time
the FP context was saved.
- Bit 2 (USED_HYBRID_FPRS) indicates whether the FP context was saved
under the hybrid FPR scheme. Essentially, when set the odd singles
are located in bits 63:32 of the preceding even indexed sc_fpregs
element.
Any userland that tests whether the sc_used_math field is zero or
non-zero will continue to function as expected. Having said that, I
could not find any userland which uses the sc_used_math field at all.
[ralf@linux-mips.org: Fixed rejects.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linux-kernel@vger.kernel.org
Cc: Richard Weinberger <richard@nod.at>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Maciej W. Rozycki <macro@codesourcery.com>
Patchwork: https://patchwork.linux-mips.org/patch/10794/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add KVM register numbers for the MIPS SIMD Architecture (MSA) registers,
and implement access to them with the KVM_GET_ONE_REG / KVM_SET_ONE_REG
ioctls when the MSA capability is enabled (exposed in a later patch) and
present in the guest according to its Config3.MSAP bit.
The MSA vector registers use the same register numbers as the FPU
registers except with a different size (128bits). Since MSA depends on
Status.FR=1, these registers are inaccessible when Status.FR=0. These
registers are returned as a single native endian 128bit value, rather
than least significant half first with each 64-bit half native endian as
the kernel uses internally.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: linux-api@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Add KVM register numbers for the MIPS FPU registers, and implement
access to them with the KVM_GET_ONE_REG / KVM_SET_ONE_REG ioctls when
the FPU capability is enabled (exposed in a later patch) and present in
the guest according to its Config1.FP bit.
The registers are accessible in the current mode of the guest, with each
sized access showing what the guest would see with an equivalent access,
and like the architecture they may become UNPREDICTABLE if the FR mode
is changed. When FR=0, odd doubles are inaccessible as they do not exist
in that mode.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: linux-api@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Clean up KVM_GET_ONE_REG / KVM_SET_ONE_REG register definitions for
MIPS, to prepare for adding a new group for FPU & MSA vector registers.
Definitions are added for common bits in each group of registers, e.g.
KVM_REG_MIPS_CP0 = KVM_REG_MIPS | 0x10000, for the coprocessor 0
registers.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for MIPS:
- a number of fixes that didn't make the 3.19 release.
- a number of cleanups.
- preliminary support for Cavium's Octeon 3 SOCs which feature up to
48 MIPS64 R3 cores with FPU and hardware virtualization.
- support for MIPS R6 processors.
Revision 6 of the MIPS architecture is a major revision of the MIPS
architecture which does away with many of original sins of the
architecture such as branch delay slots. This and other changes in
R6 require major changes throughout the entire MIPS core
architecture code and make up for the lion share of this pull
request.
- finally some preparatory work for eXtendend Physical Address
support, which allows support of up to 40 bit of physical address
space on 32 bit processors"
[ Ahh, MIPS can't leave the PAE brain damage alone. It's like
every CPU architect has to make that mistake, but pee in the snow
by changing the TLA. But whether it's called PAE, LPAE or XPA,
it's horrid crud - Linus ]
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
MIPS: sead3: Corrected get_c0_perfcount_int
MIPS: mm: Remove dead macro definitions
MIPS: OCTEON: irq: add CIB and other fixes
MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
MIPS: OCTEON: More OCTEONIII support
MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
MIPS: OCTEON: Update octeon-model.h code for new SoCs.
MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
MIPS: OCTEON: Implement the core-16057 workaround
MIPS: OCTEON: Delete unused COP2 saving code
MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
MIPS: OCTEON: Save and restore CP2 SHA3 state
MIPS: OCTEON: Fix FP context save.
MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
MIPS: boot: Provide more uImage options
MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
MIPS: ip22-gio: Remove legacy suspend/resume support
mips: pci: Add ifdef around pci_proc_domain
...
Provide correct siginfo_t.si_stime on MIPS64
Bug description:
MIPS version of copy_siginfo() is not aware of alignment on platforms with
64-bit long integers, which leads to an incorrect si_stime passed to signal
handlers, because the last element (si_stime) of _sifields._sigchld is not
copied. If _MIPS_SZLONG is 64, then the _sifields starts at the offset of
4 * sizeof(int).
Patch description:
Use the generic copy_siginfo, which doesn't have this problem.
Signed-off-by: Petr Malat <oss@malat.biz>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8671/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS R6 introduced the following two branch instructions for COP1:
BC1EQZ: Branch if Cop1 (FPR) Register Bit 0 is Equal to Zero
BC1NEZ: Branch if Cop1 (FPR) Register Bit 0 is Not Equal to Zero
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>
Pull MIPS updates from Ralf Baechle:
"This is an unusually large pull request for MIPS - in parts because
lots of patches missed the 3.18 deadline but primarily because some
folks opened the flood gates.
- Retire the MIPS-specific phys_t with the generic phys_addr_t.
- Improvments for the backtrace code used by oprofile.
- Better backtraces on SMP systems.
- Cleanups for the Octeon platform code.
- Cleanups and fixes for the Loongson platform code.
- Cleanups and fixes to the firmware library.
- Switch ATH79 platform to use the firmware library.
- Grand overhault to the SEAD3 and Malta interrupt code.
- Move the GIC interrupt code to drivers/irqchip
- Lots of GIC cleanups and updates to the GIC code to use modern IRQ
infrastructures and features of the kernel.
- OF documentation updates for the GIC bindings
- Move GIC clocksource driver to drivers/clocksource
- Merge GIC clocksource driver with clockevent driver.
- Further updates to bring the GIC clocksource driver up to date.
- R3000 TLB code cleanups
- Improvments to the Loongson 3 platform code.
- Convert pr_warning to pr_warn.
- Merge a bunch of small lantiq and ralink fixes that have been
staged/lingering inside the openwrt tree for a while.
- Update archhelp for IP22/IP32
- Fix a number of issues for Loongson 1B.
- New clocksource and clockevent driver for Loongson 1B.
- Further work on clk handling for Loongson 1B.
- Platform work for Broadcom BMIPS.
- Error handling cleanups for TurboChannel.
- Fixes and optimization to the microMIPS support.
- Option to disable the FTLB.
- Dump more relevant information on machine check exception
- Change binfmt to allow arch to examine PT_*PROC headers
- Support for new style FPU register model in O32
- VDSO randomization.
- BCM47xx cleanups
- BCM47xx reimplement the way the kernel accesses NVRAM information.
- Random cleanups
- Add support for ATH25 platforms
- Remove pointless locking code in some PCI platforms.
- Some improvments to EVA support
- Minor Alchemy cleanup"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (185 commits)
MIPS: Add MFHC0 and MTHC0 instructions to uasm.
MIPS: Cosmetic cleanups of page table headers.
MIPS: Add CP0 macros for extended EntryLo registers
MIPS: Remove now unused definition of phys_t.
MIPS: Replace use of phys_t with phys_addr_t.
MIPS: Replace MIPS-specific 64BIT_PHYS_ADDR with generic PHYS_ADDR_T_64BIT
PCMCIA: Alchemy Don't select 64BIT_PHYS_ADDR in Kconfig.
MIPS: lib: memset: Clean up some MIPS{EL,EB} ifdefery
MIPS: iomap: Use __mem_{read,write}{b,w,l} for MMIO
MIPS: <asm/types.h> fix indentation.
MAINTAINERS: Add entry for BMIPS multiplatform kernel
MIPS: Enable VDSO randomization
MIPS: Remove a temporary hack for debugging cache flushes in SMTC configuration
MIPS: Remove declaration of obsolete arch_init_clk_ops()
MIPS: atomic.h: Reformat to fit in 79 columns
MIPS: Apply `.insn' to fixup labels throughout
MIPS: Fix microMIPS LL/SC immediate offsets
MIPS: Kconfig: Only allow 32-bit microMIPS builds
MIPS: signal.c: Fix an invalid cast in ISA mode bit handling
MIPS: mm: Only build one microassembler that is suitable
...
Ralf Baechle
Yousong Zhou
Markos Chandras
Paul Burton
Leonid Yegoshin
James Hogan
Linus Torvalds
Petr Malat