After we removed all the dead wood it turns out only two architectures
actually implement dma_cache_sync as a real op: mips and parisc.  Add
a cache_sync method to struct dma_map_ops and implement it for the
mips defualt DMA ops, and the parisc pa11 ops.

Note that arm, arc and openrisc support DMA_ATTR_NON_CONSISTENT, but
never provided a functional dma_cache_sync implementations, which
seems somewhat odd.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>

The FPU emulator includes 2 calls to pr_err() which are triggered by
invalid instruction encodings for MIPSr6 cmp.cond.fmt instructions.
These cases are not kernel errors, merely invalid instructions which are
already handled by delivering a SIGILL which will provide notification
that something failed in cases where that makes sense.

In cases where that SIGILL is somewhat expected & being handled, for
example when crashme happens to generate one of the affected bad
encodings, the message is printed with no useful context about what
triggered it & spams the kernel log for no good reason.

Remove the pr_err() calls to make crashme run silently & treat the bad
encodings the same way we do others, with a SIGILL & no further kernel
log output.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: f8c3c671 ("MIPS: math-emu: Add support for the CMP.condn.fmt R6 instruction")
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.3+
Patchwork: https://patchwork.linux-mips.org/patch/17253/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When configuring the kernel using one of the generic MIPS defconfig
targets, the generic-board-config.sh script is used to check
requirements listed in board config fragments against a reference config
in order to determine which board config fragments to merge into the
final config.

When specifying O= to configure in a directory other than the kernel
source directory, this generic-board-config.sh script is invoked in the
directory that we are configuring in (ie. the directory that O equals),
and the path to the reference config is relative to the current
directory. The script then changes the current directory to the source
tree, which unfortunately breaks later access to the reference file
since its path is relative to a directory that is no longer the current
working directory. This results in configuration failing with errors
such as:

  $ make ARCH=mips O=tmp 32r2_defconfig
  make[1]: Entering directory '/home/pburton/src/linux/tmp'
  Using ../arch/mips/configs/generic_defconfig as base
  Merging ../arch/mips/configs/generic/32r2.config
  Merging ../arch/mips/configs/generic/eb.config
  grep: ./.config.32r2_defconfig: No such file or directory
  grep: ./.config.32r2_defconfig: No such file or directory
  The base file '.config' does not exist.  Exit.
  make[1]: *** [arch/mips/Makefile:505: 32r2_defconfig] Error 1
  make[1]: Leaving directory '/home/pburton/src/linux-ingenic/tmp'
  make: *** [Makefile:145: sub-make] Error 2

Fix this by avoiding changing the working directory in
generic-board-config.sh, instead using full paths to files under
$(srctree)/ where necessary.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: 27e0d4b0 ("MIPS: generic: Allow filtering enabled boards by requirements")
Cc: linux-mips@linux-mips.org
Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: kbuild-all@01.org
Patchwork: https://patchwork.linux-mips.org/patch/17231/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit 8263db4d ("MIPS: cmpxchg: Implement __cmpxchg() as a
function") refactored our implementation of __cmpxchg() to be a function
rather than a macro, with the aim of making it easier to read & modify.
Unfortunately the commit breaks use of cmpxchg() for signed 32 bit
values when we have a 64 bit kernel with kernel_uses_llsc == false,
because:

 - In cmpxchg_local() we cast the old value to the type the pointer
   points to, and then to an unsigned long. If the pointer points to a
   signed type smaller than 64 bits then the old value will be sign
   extended to 64 bits. That is, bits beyond the size of the pointed to
   type will be set to 1 if the old value is negative. In the case of a
   signed 32 bit integer with a negative value, bits 63:32 will all be
   set.

 - In __cmpxchg_asm() we load the value from memory, ie. dereference the
   pointer, and store the value as an unsigned integer (__ret) whose
   size matches the pointer. For a 32 bit cmpxchg() this means we store
   the value in a u32, because the pointer provided to __cmpxchg_asm()
   by __cmpxchg() is of type volatile u32 *.

 - __cmpxchg_asm() then checks whether the value in memory (__ret)
   matches the provided old value, by comparing the two values. This
   results in the u32 being promoted to a 64 bit unsigned long to match
   the old argument - however because both types are unsigned the value
   is zero extended, which does not match the sign extension performed
   on the old value in cmpxchg_local() earlier.

This mismatch means that unfortunate cmpxchg() calls can incorrectly
fail for 64 bit kernels with kernel_uses_llsc == false. This is the case
on at least non-SMP Cavium Octeon kernels, which hardcode
kernel_uses_llsc in their cpu-feature-overrides.h header. Using a
v4.13-rc7 kernel configured using cavium_octeon_defconfig with SMP
manually disabled, this presents itself as oddity when we reach
userland - for example:

  can't run '/bin/mount': Text file busy
  can't run '/bin/mkdir': Text file busy
  can't run '/bin/mkdir': Text file busy
  can't run '/bin/mount': Text file busy
  can't run '/bin/hostname': Text file busy
  can't run '/etc/init.d/rcS': Text file busy
  can't run '/sbin/getty': Text file busy
  can't run '/sbin/getty': Text file busy

It appears that some part of the init process, which is in this case
buildroot's busybox init, is running successfully. It never manages to
reach the login prompt though, and complains about /sbin/getty being
busy repeatedly and indefinitely.

Fix this by casting the old value provided to __cmpxchg_asm() to an
appropriately sized unsigned integer, such that we consistently
zero-extend avoiding the mismatch. The __cmpxchg_small() case for 8 & 16
bit values is unaffected because __cmpxchg_small() already masks
provided values appropriately.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: 8263db4d ("MIPS: cmpxchg: Implement __cmpxchg() as a function")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17226/
Cc: linux-mips@linux-mips.org
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Set the default number of RX and TX queues due to
the recent changes of stmmac driver.
Otherwise the ethernet will crash once it starts.
Signed-off-by: NKelvin Cheung <keguang.zhang@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17452/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Compiling ebpf_jit.c with gcc 4.9 results in a (likely spurious)
compiler warning, as gcc has detected that the variable "target" may be
used uninitialised. Since -Werror is active, this is treated as an error
and causes a kernel build failure whenever CONFIG_MIPS_EBPF_JIT is
enabled.

arch/mips/net/ebpf_jit.c: In function 'build_one_insn':
arch/mips/net/ebpf_jit.c:1118:80: error: 'target' may be used
uninitialized in this function [-Werror=maybe-uninitialized]
    emit_instr(ctx, j, target);
                                                                                ^
cc1: all warnings being treated as errors

Fix this by initialising "target" to 0. If it really is used
uninitialised this would result in a jump to 0 and a detectable run time
failure.
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Fixes: b6bd53f9 ("MIPS: Add missing file for eBPF JIT.")
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v4.13+
Patchwork: https://patchwork.linux-mips.org/patch/17375/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Drop  the __init from pcibios_map_irq() to make this section mis-
match go away:

WARNING: vmlinux.o(.text+0x56acd4): Section mismatch in reference from the function pcibios_scanbus() to the function .init.text:pcibios_map_irq()
The function pcibios_scanbus() references
the function __init pcibios_map_irq().
This is often because pcibios_scanbus lacks a __init
annotation or the annotation of pcibios_map_irq is wrong.

Run-Tested only on Alchemy.
Signed-off-by: NManuel Lauss <manuel.lauss@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17267/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The inline asm in __write_64bit_c0_split() modifies the 64-bit input
operand by shifting the high register left by 32, and constructing the
full 64-bit value in the low register (even on a 32-bit kernel), so if
that value is used again it could cause breakage as GCC would assume the
registers haven't changed when they have.

To quote the GCC extended asm documentation:
> Warning: Do not modify the contents of input-only operands (except for
> inputs tied to outputs). The compiler assumes that on exit from the
> asm statement these operands contain the same values as they had
> before executing the statement.

Avoid modifying the input by using a temporary variable as an output
which is modified instead of the input and not otherwise used. The asm
is always __volatile__ so GCC shouldn't optimise it out. The low
register of the temporary output is written before the high register of
the input is read, so we have two constraint alternatives, one where
both use the same registers (for when the input value isn't subsequently
used), and one with an early clobber on the output in case the low
output uses the same register as the high input. This allows the
resulting assembly to remain mostly unchanged.

A diff of a MIPS32r6 kernel reveals only three differences, two in
relation to write_c0_r10k_diag() in cpu_probe() (register allocation
rearranged slightly but otherwise identical), and one in relation to
write_c0_cvmmemctl2() in kvm_vz_local_flush_guesttlb_all(), but the
octeon CPU is only supported on 64-bit kernels where
__write_64bit_c0_split() isn't used so that shouldn't matter in
practice. So there currently doesn't appear to be anything broken by
this bug.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17315/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

msp71xx_defconfig can not be built at the in v4.14-rc1

arch/mips/pmcs-msp71xx/msp_smp.c:72:2: error: implicit declaration of function 'set_vi_handler' [-Werror=implicit-function-declaration]

I don't know what caused the regression, but including the right
header is the obvious fix.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17309/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit c311c797 ("cpumask: make "nr_cpumask_bits" unsigned")
modified mipspmu_event_init() to cast the struct perf_event cpu field to
an unsigned integer before it is compared with nr_cpumask_bits (and
*ahem* did so without copying the linux-mips mailing list or any MIPS
developers...). This is broken because the cpu field may be -1 for
events which follow a process rather than being affine to a particular
CPU. When this is the case the cast to an unsigned int results in a
value equal to ULONG_MAX, which is always greater than nr_cpumask_bits
so we always fail mipspmu_event_init() and return -ENODEV.

The check against nr_cpumask_bits seems nonsensical anyway, so this
patch simply removes it. The cpu field is going to either be -1 or a
valid CPU number. Comparing it with nr_cpumask_bits is effectively
checking that it's a valid cpu number, but it seems safe to rely on the
core perf events code to ensure that's the case.

The end result is that this fixes use of perf on MIPS when not
constraining events to a particular CPU, and fixes the "perf list hw"
command which fails to list any events without this.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Fixes: c311c797 ("cpumask: make "nr_cpumask_bits" unsigned")
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.12+
Patchwork: https://patchwork.linux-mips.org/patch/17323/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

04c81c72 ("MIPS: PCI: Replace pci_fixup_irqs() call with host bridge
IRQ mapping hooks") moved the PCI IRQ fixup to the new host bridge
map/swizzle_irq() hooks mechanism. Those hooks can also be called after
boot, when all the __init/__initdata/__initconst sections have been freed.
Therefore, functions called by them (and the data they refer to) must not
be marked as __init/__initdata/__initconst lest compilation trigger section
mismatch warnings.

Fix all the board files map_irq() hooks by simply removing the respective
__init/__initdata/__initconst section markers and by adding another
persistent hook IRQ map for the txx9 board files.

Fixes: 04c81c72 ("MIPS: PCI: Replace pci_fixup_irqs() call with host bridge IRQ mapping hooks")
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steve French <smfrench@gmail.com>

For example, the following could occur, making us miss a wakeup:

CPU0					CPU1
kvm_vcpu_block				kvm_mips_comparecount_func
					  [L] swait_active(&vcpu->wq)
  [S] prepare_to_swait(&vcpu->wq)
  [L] if (!kvm_vcpu_has_pending_timer(vcpu))
         schedule()                       [S] queue_timer_int(vcpu)

Ensure that the swait_active() check is not hoisted over the interrupt.
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Where possible, call memset16(), memmove() or memcpy() instead of using
open-coded loops.  I don't like the calling convention that uses a byte
count instead of a count of u16s, but it's a little late to change that.
Reduces code size of fbcon.o by almost 400 bytes on my laptop build.

[akpm@linux-foundation.org: fix build]
Link: http://lkml.kernel.org/r/20170720184539.31609-9-willy@infradead.orgSigned-off-by: NMatthew Wilcox <mawilcox@microsoft.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Introduce MADV_WIPEONFORK semantics, which result in a VMA being empty
in the child process after fork.  This differs from MADV_DONTFORK in one
important way.

If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes.  The address ranges are still valid, they are just empty.

If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.

Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.

MADV_WIPEONFORK only works on private, anonymous VMAs.

The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.

Examples of this would be:
 - systemd/pulseaudio API checks (fail after fork) (replacing a getpid
   check, which is too slow without a PID cache)
 - PKCS#11 API reinitialization check (mandated by specification)
 - glibc's upcoming PRNG (reseed after fork)
 - OpenSSL PRNG (reseed after fork)

The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious.  However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.

A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.

It would be better to have the kernel take care of this automatically.

The patch also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.

This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:

    https://man.openbsd.org/minherit.2

[akpm@linux-foundation.org: numerically order arch/parisc/include/uapi/asm/mman.h #defines]
Link: http://lkml.kernel.org/r/20170811212829.29186-3-riel@redhat.comSigned-off-by: NRik van Riel <riel@redhat.com>
Reported-by: NFlorian Weimer <fweimer@redhat.com>
Reported-by: NColm MacCártaigh <colm@allcosts.net>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A non-default huge page size can be encoded in the flags argument of the
mmap system call.  The definitions for these encodings are in arch
specific header files.  However, all architectures use the same values.

Consolidate all the definitions in the primary user header file
(uapi/linux/mman.h).  Include definitions for all known huge page sizes.
Use the generic encoding definitions in hugetlb_encode.h as the basis
for these definitions.

Link: http://lkml.kernel.org/r/1501527386-10736-3-git-send-email-mike.kravetz@oracle.comSigned-off-by: NMike Kravetz <mike.kravetz@oracle.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. The code that was added violates code style rules with long
lines caused by lots of nested conditionals.

The added code interprets (inline) any known stack pointer manipulation
instruction to find the stack frame size. Handling the microMIPS cases
added quite a bit of complication to this function.

Refactor is_sp_move_ins to perform the interpretation of the immediate
as the instruction manipulating the stack pointer is found. This reduces
the amount of indentation required in get_frame_info, and more closely
matches the operation of is_ra_save_ins.
Suggested-by: NMaciej W. Rozycki <macro@imgtec.com>
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16958/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The stack unwinding code uses the mips_instuction union to decode the
instructions it finds. That union uses the __BITFIELD_FIELD macro to
reorder depending on endianness. The stack unwinding code always places
16bit instructions in halfword 1 of the union. This makes the union
accesses correct for little endian systems. Similarly, 32bit
instructions are reordered such that they are correct for little endian
systems. This handling leaves unwinding the stack on big endian systems
broken, as the mips_instruction union will then look for the fields in
the wrong halfword.

To fix this, use a logical shift to place the 16bit instruction into the
correct position in the word field of the union. Use the same shifting
to order the 2 halfwords of 32bit instuctions. Then replace accesses to
the halfword with accesses to the shifted word.
In the case of the ADDIUS5 instruction, switch to using the
mm16_r5_format union member to avoid the need for a 16bit shift.

Fixes: 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16956/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When the immediate encoded in the instruction is accessed, it is sign
extended due to being a signed value being assigned to a signed integer.
The ISA specifies that this operation is an unsigned operation.
The sign extension leads us to incorrectly decode:

801e9c8e:       cbf1            sw      ra,68(sp)

As having an immediate of 1073741809.

Since the instruction format does not specify signed/unsigned, and this
is currently the only location to use this instuction format, change it
to an unsigned immediate.

Fixes: bb9bc468 ("MIPS: Calculate microMIPS ra properly when unwinding the stack")
Suggested-by: NPaul Burton <paul.burton@imgtec.com>
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Miodrag Dinic <miodrag.dinic@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16957/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. Unfortunately the decoding of the addiusp instruction was
incorrect, and performed a left shift by 2 bits to the raw immediate,
rather than decoding the immediate and then performing the shift, as
documented in the ISA.

This led to incomplete stack traces, due to incorrect frame sizes being
calculated. For example the instruction:
801faee0 <do_sys_poll>:
801faee0:       4e25            addiu   sp,sp,-952

As decoded by objdump, would be interpreted by the existing code as
having manipulated the stack pointer by +1096.

Fix this by changing the order of decoding the immediate and applying
the left shift. Also change to accessing the instuction through the
union to avoid the endianness problem of accesing halfword[0], which
will fail on big endian systems.

Cope with the special behaviour of immediates 0x0, 0x1, 0x1fe and 0x1ff
by XORing with 0x100 again if mod(immediate) < 4. This logic was tested
with the following test code:

int main(int argc, char **argv)
{
	unsigned int enc;
	int imm;

	for (enc = 0; enc < 512; ++enc) {
		int tmp = enc << 2;
		imm = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0));
		unsigned short tmp = enc;
		tmp = (tmp ^ 0x100) - 0x100;
		if ((unsigned short)(tmp + 2) < 4)
			tmp ^= 0x100;
		imm = -(signed short)(tmp << 2);
		printf("%#x\t%d\t->\t(%#x\t%d)\t%#x\t%d\n",
		       enc, enc,
		       (short)tmp, (short)tmp,
		       imm, imm);
	}
	return EXIT_SUCCESS;
}

Which generates the table:

input encoding	->	tmp (matching manual)	frame size
-----------------------------------------------------------------------
0	0	->	(0x100		256)	0xfffffc00	-1024
0x1	1	->	(0x101		257)	0xfffffbfc	-1028
0x2	2	->	(0x2		2)	0xfffffff8	-8
0x3	3	->	(0x3		3)	0xfffffff4	-12
...
0xfe	254	->	(0xfe		254)	0xfffffc08	-1016
0xff	255	->	(0xff		255)	0xfffffc04	-1020
0x100	256	->	(0xffffff00	-256)	0x400		1024
0x101	257	->	(0xffffff01	-255)	0x3fc		1020
...
0x1fc	508	->	(0xfffffffc	-4)	0x10		16
0x1fd	509	->	(0xfffffffd	-3)	0xc		12
0x1fe	510	->	(0xfffffefe	-258)	0x408		1032
0x1ff	511	->	(0xfffffeff	-257)	0x404		1028

Thanks to James Hogan for the test code & verifying the logic.

Fixes: 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
Suggested-by: NJames Hogan <james.hogan@imgtec.com>
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16955/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The addiusp instruction uses the pool16d opcode, with bit 0 of the
immediate set. The test for the addiusp opcode erroneously did a logical
and of the immediate with mm_addiusp_func, which has value 1, so this
test always passes when the immediate is non-zero.

Fix the test by replacing the logical and with a bitwise and.

Fixes: 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16954/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
added fairly broken support for handling 16bit microMIPS instructions in
get_frame_info(). It adjusts the instruction pointer by 16bits in the
case of a 16bit sp move instruction, but not any other 16bit
instruction.

Commit b6c7a324 ("MIPS: Fix get_frame_info() handling of microMIPS
function size") goes some way to fixing get_frame_info() to iterate over
microMIPS instuctions, but the instruction pointer is still manipulated
using a postincrement, and is of union mips_instruction type. Since the
union is sized to the largest member (a word), but microMIPS
instructions are a mix of halfword and word sizes, the function does not
always iterate correctly, ending up misaligned with the instruction
stream and interpreting it incorrectly.

Since the instruction modifying the stack pointer is usually the first
in the function, that one is usually handled correctly. But the
instruction which saves the return address to the sp is some variable
number of instructions into the frame and is frequently missed due to
not being on a word boundary, leading to incomplete walking of the
stack.

Fix this by incrementing the instruction pointer based on the size of
the previously decoded instruction (& remove the hack introduced by
commit 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
which adjusts the instruction pointer in the case of a 16bit sp move
instruction, but not any other).

Fixes: 34c2f668 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16953/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make the behaviour of clk_get_rate consistent with common clk's
clk_get_rate by accepting NULL clocks as parameter. Some device
drivers rely on this, and will cause an OOPS otherwise.

Fixes: 3f0a06b0 ("MIPS: ralink: adds clkdev code")
Reported-by: NMathias Kresin <dev@kresin.me>
Signed-off-by: NJonas Gorski <jonas.gorski@gmail.com>
Cc: John Crispin <john@phrozen.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16778/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make the behaviour of clk_get_rate consistent with common clk's
clk_get_rate by accepting NULL clocks as parameter, as some device
drivers rely on this.

Make the behaviour of clk_get_rate consistent with common clk's
clk_get_rate by accepting NULL clocks as parameter. Some device
drivers rely on this, and will cause an OOPS otherwise.

Fixes: f8ede0f7 ("MIPS: Loongson 2F: Add CPU frequency scaling support")
Reported-by: NMathias Kresin <dev@kresin.me>
Signed-off-by: NJonas Gorski <jonas.gorski@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16777/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make the behaviour of clk_get_rate consistent with common clk's
clk_get_rate by accepting NULL clocks as parameter. Some device
drivers rely on this, and will cause an OOPS otherwise.

Fixes: e7300d04 ("MIPS: BCM63xx: Add support for the Broadcom BCM63xx family of SOCs.")
Reported-by: NMathias Kresin <dev@kresin.me>
Signed-off-by: NJonas Gorski <jonas.gorski@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16776/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make the behaviour of clk_get_rate consistent with common clk's
clk_get_rate by accepting NULL clocks as parameter. Some device
drivers rely on this, and will cause an OOPS otherwise.

Fixes: 780019dd ("MIPS: AR7: Implement clock API")
Signed-off-by: NJonas Gorski <jonas.gorski@gmail.com>
Reported-by: NMathias Kresin <dev@kresin.me>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16775/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The channels are only 0x40 bytes large, so 0x40 would be the next one's
CHANCFG_REG. Also the position makes it clear that this was intended to
be 0x04. So clearly a typo.
Signed-off-by: NJonas Gorski <jonas.gorski@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: bcm-kernel-feedback-list@broadcom.com
Patchwork: https://patchwork.linux-mips.org/patch/15316/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The MIPS frame save code was just saving a few registers, enough to
do a backtrace if every function set up a frame.  However, this is
not working if you are using DWARF unwinding, because most of the
registers are wrong.  This was causing kdump backtraces to be short
or bogus.

So save all the registers.
Signed-off-by: NCorey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16989/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This will allow kdump dumps to work correclty with MIPS and
future DWARF unwinding of the stack to give accurate tracebacks.
Signed-off-by: NCorey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16990/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Modify the SAVE_SOME macro to look more like a standard
function, doing the arithmetic for the frame on the SP
register instead of copying it from K1, and by saving
the stored EPC from the RA.  This lets the get_frame_info()
function process this function like any other.  It also
remove an instruction or two from the kernel entry,
making it more efficient.

unwind_stack_by_address() has special handling for
the top of the interrupt stack, but without this change
unwinding will still fail if you get an interrupt while
handling an interrupt and try to do a traceback from
the second interrupt.

This change modifies the get_saved_sp macro to
optionally store the fetched value right into sp and store the
old SP value into K0.  Then it's just a matter of subtracting
the frame from SP and storing the old SP from K0.

This required changing the DADDI workaround a bit, since K0
holds the SP, we had to use K1 for AT.  But it eliminated
some of the special handling for the DADDI workaround.

Saving the RA register was moved up to before fetching the
CP0_EPC register, so the CP0_EPC register could be stored
into RA and the saved.  This lets the traceback code know
where RA is actually stored.
Signed-off-by: NCorey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16991/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

I saw two problems when doing backtraces:

The compiler was putting a "fast return" at the top of some
functions, before it set up the frame.  The backtrace code
would stop when it saw a jump instruction, so it would never
get to the stack frame setup and would thus misinterpret it.
To fix this, don't look for jump instructions until the
frame setup has been seen.

The assembly code here is:

ffffffff80b885a0 <serial8250_handle_irq>:
ffffffff80b885a0:       c8a00003        bbit0   a1,0x0,ffffffff80b885b0 <serial8250_handle_irq+0x10>
ffffffff80b885a4:       0000102d        move    v0,zero
ffffffff80b885a8:       03e00008        jr      ra
ffffffff80b885ac:       00000000        nop
ffffffff80b885b0:       67bdffd0        daddiu  sp,sp,-48
ffffffff80b885b4:       ffb00008        sd      s0,8(sp)

The second problem was the compiler was putting the last
instruction of the frame save in the delay slot of the
jump instruction.  If it saved the RA in there, the
backtrace could would miss it and misinterpret the frame.
To fix this, make sure to process the instruction after
the first jump seen.

The assembly code for this is:

ffffffff80806fd0 <plat_irq_dispatch>:
ffffffff80806fd0:       67bdffd0        daddiu  sp,sp,-48
ffffffff80806fd4:       ffb30020        sd      s3,32(sp)
ffffffff80806fd8:       24130018        li      s3,24
ffffffff80806fdc:       ffb20018        sd      s2,24(sp)
ffffffff80806fe0:       3c12811c        lui     s2,0x811c
ffffffff80806fe4:       ffb10010        sd      s1,16(sp)
ffffffff80806fe8:       3c11811c        lui     s1,0x811c
ffffffff80806fec:       ffb00008        sd      s0,8(sp)
ffffffff80806ff0:       3c10811c        lui     s0,0x811c
ffffffff80806ff4:       08201c03        j       ffffffff8080700c <plat_irq_dispa
tch+0x3c>
ffffffff80806ff8:       ffbf0028        sd      ra,40(sp)
Signed-off-by: NCorey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16992/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The jz4740-rtc driver supports both jz4740 & jz4780, setup the compatible
string to jz4780.
Signed-off-by: NMathieu Malaterre <malat@debian.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17237/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Update the Ci20's defconfig to enable the JZ4780's RTC driver.
Signed-off-by: NMathieu Malaterre <malat@debian.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17236/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Use proper ssize_t and size_t types for the return value and count
argument, move the offset last and make it an in/out argument like
all other read/write helpers, and make the buf argument a void pointer
to get rid of lots of casts in the callers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add accessor function octeon_irq_get_block_domain() for cores
with a CIU3.
Signed-off-by: NSteven J. Hill <steven.hill@cavium.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-watchdog@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17210/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Updates CSR read/write functions to be aware of nodes present in
systems with CIU3 support.
Signed-off-by: NSteven J. Hill <Steven.Hill@cavium.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-watchdog@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17211/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NSteven J. Hill <steven.hill@cavium.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-watchdog@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17208/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Used by the Octeon watchdog driver to get the address of the
firmware boot vector.
Signed-off-by: NSteven J. Hill <steven.hill@cavium.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-watchdog@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17206/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The RCU register are now access through separates drivers. remove the
last pieces of the old implementation.

The GPHY reset bits are now set by the GPHY driver which registers a
reboot notifier. The reboot is triggered by a syscon-reboot driver and
the MIPS specific parts are done by the generic MIPS implementation in
arch/mips/kernel/reset.c.
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Cc: john@phrozen.org
Cc: robh@kernel.org
Cc: andy.shevchenko@gmail.com
Cc: p.zabel@pengutronix.de
Cc: kishon@ti.com
Cc: mark.rutland@arm.com
Cc: linux-mips@linux-mips.org
Cc: linux-mtd@lists.infradead.org
Cc: linux-watchdog@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-spi@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17131/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This is now done in a PHY driver.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Cc: martin.blumenstingl@googlemail.com
Cc: john@phrozen.org
Cc: robh@kernel.org
Cc: andy.shevchenko@gmail.com
Cc: p.zabel@pengutronix.de
Cc: kishon@ti.com
Cc: mark.rutland@arm.com
Cc: linux-mips@linux-mips.org
Cc: linux-mtd@lists.infradead.org
Cc: linux-watchdog@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-spi@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17130/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This driver starts the DWC2 core(s) built into the XWAY SoCs and provides
the PHY interfaces for each core. The phy instances can be passed to the
dwc2 driver, which already supports the generic phy interface.
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>
Acked-by: NKishon Vijay Abraham I <kishon@ti.com>
Acked-by: NRob Herring <robh@kernel.org>
Cc: martin.blumenstingl@googlemail.com
Cc: john@phrozen.org
Cc: andy.shevchenko@gmail.com
Cc: p.zabel@pengutronix.de
Cc: mark.rutland@arm.com
Cc: linux-mips@linux-mips.org
Cc: linux-mtd@lists.infradead.org
Cc: linux-watchdog@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-spi@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17127/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>