We have the following means for encoding writable or dirty ptes:

                                PTE_DIRTY       PTE_RDONLY
!pte_dirty && !pte_write        0               1
!pte_dirty && pte_write         0               1
pte_dirty && !pte_write         1               1
pte_dirty && pte_write          1               0

So we can't distinguish between writable clean ptes and read only
ptes. This can cause problems with ptes being incorrectly flagged as
read only when they are writable but not dirty.

This patch introduces a new software bit PTE_WRITE which allows us to
correctly identify writable ptes. PTE_RDONLY is now only clear for
valid ptes where a page is both writable and dirty.
Signed-off-by: NSteve Capper <steve.capper@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Expand out the pte manipulation functions. This makes our life easier
when using things like tags and cscope.
Signed-off-by: NSteve Capper <steve.capper@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

So any FIQ handling is superfluous at the moment.  The functions to
disable/enable FIQs is kept around if ever someone needs them in the
future, but existing calling sites including arch_cpu_idle_prepare()
may go for now.
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Fix the function name of comment of cpu_do_switch_mm,
because cpu_do_switch_mm is the correct name.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

arm64/include/asm/dma-contiguous.h is trying to include
<asm-genric/dma-contiguous.h> which does not exist, and thus failing
build for arm64 if we enable CONFIG_DMA_CMA. This patch fixes build
error by removing unwanted header inclusion from arm64's dma-contiguous.h.
Signed-off-by: NPankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: NSomraj Mani <somraj.mani@samsung.com>
Acked-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The introduction of percpu offset optimisation through tpidr_el1 in:

Commit id :71586276
"arm64: percpu: implement optimised pcpu access using tpidr_el1"

requires cpu_{suspend/resume} to restore the tpidr_el1 register upon resume
so that percpu variables can be addressed correctly when a CPU comes out
of reset from warm-boot.

This patch fixes cpu_{suspend}/{resume} tpidr_el1 restoration on resume, by
calling the set_my_cpu_offset C API, as it is done on primary and secondary
CPUs on cold boot, so that, even if the register used to store the percpu
offset is changed, the save and restore of general purpose registers does not
have to be updated.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Fix the function name of comment of __flush_dcache_area,
because __flush_dcache_area is the correct name. Also,
the missing variable 'size' is added to the comment.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Use 'ubfm' for the bitfield move instruction; thus, single
instruction can be used instead of two instructions, when
getting the minimum D-cache line size from CTR_EL0 register.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Commit 64681787 (arm64: let the core code deal with preempt_count)
changed the code, but left the comments unchanged, fix it.
Signed-off-by: NNeil Zhang <zhangwm@marvell.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

When a CPU resumes from low-power, it restores HW breakpoint and
watchpoint slots through a CPU PM notifier. Since we want to enable
debugging as early as possible in the resume path, the mdscr content
is restored along the general purpose registers in the cpu_suspend API
and debug exceptions are reenabled when cpu_suspend returns. Since the
CPU PM notifier is run after a CPU has been resumed, we cannot expect
HW breakpoint registers to contain sane values till the notifier is run,
since the HW breakpoints registers content is unknown at reset; this means
that the CPU might run with debug exceptions enabled, mdscr restored but HW
breakpoint registers containing junk values that can trigger spurious
debug exceptions.

This patch fixes current HW breakpoints restore by moving the HW breakpoints
registers restoration to the cpu_suspend API, before the debug exceptions are
enabled. This way, as soon as the cpu_suspend function returns the
kernel can resume debugging with sane values in HW breakpoint registers.
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Use macro JUMP_LABEL_TRUE_BRANCH instead of hard-coding for better
readability.
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Acked-by: NJason Baron <jbaron@akamai.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Optimize jump label implementation for ARM64 by dynamically patching
kernel text.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

As commit a9468f30 "ARM: 7333/2: jump label: detect %c
support for ARM", this patch detects the same thing for ARM64
because some ARM64 GCC versions have the same issue.

Some versions of ARM64 GCC which do support asm goto, do not
support the %c specifier. Since we need the %c to support jump
labels on ARM64, detect that too in the asm goto detection script
to avoid build errors with these versions.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Introduce aarch64_insn_gen_{nop|branch_imm}() helper functions, which
will be used to implement jump label on ARM64.
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Function encode_insn_immediate() will be used by other instruction
manipulate related functions, so move it into insn.c and rename it
as aarch64_insn_encode_immediate().
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Introduce three interfaces to patch kernel and module code:
aarch64_insn_patch_text_nosync():
	patch code without synchronization, it's caller's responsibility
	to synchronize all CPUs if needed.
aarch64_insn_patch_text_sync():
	patch code and always synchronize with stop_machine()
aarch64_insn_patch_text():
	patch code and synchronize with stop_machine() if needed
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Introduce basic aarch64 instruction decoding helper
aarch64_get_insn_class() and aarch64_insn_hotpatch_safe().
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NJiang Liu <liuj97@gmail.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Will Deacon observed that kvmtool uses a size of 0x200 for virtio
block memory region and that the virtio block spec only uses 31 bytes in
the device specific region at 0x100 so reduce the region to a less
wasteful 0x200.
Signed-off-by: NMark Brown <broonie@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The __data_loc variable is an unused left over from the 32 bit arm implementation.
Remove that variable and adjust the __mmap_switched startup routine accordingly.

Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

* tag 'arm64-suspend' of git://linux-arm.org/linux-2.6-lp:
  arm64: add CPU power management menu/entries
  arm64: kernel: add PM build infrastructure
  arm64: kernel: add CPU idle call
  arm64: enable generic clockevent broadcast
  arm64: kernel: implement HW breakpoints CPU PM notifier
  arm64: kernel: refactor code to install/uninstall breakpoints
  arm: kvm: implement CPU PM notifier
  arm64: kernel: implement fpsimd CPU PM notifier
  arm64: kernel: cpu_{suspend/resume} implementation
  arm64: kernel: suspend/resume registers save/restore
  arm64: kernel: build MPIDR_EL1 hash function data structure
  arm64: kernel: add MPIDR_EL1 accessors macros

Conflicts:
	arch/arm64/Kconfig

arm64 bit targets need the features CMA provides. Add the appropriate
hooks, header files, and Kconfig to allow this to happen.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Although parts of the DMA apis may properly check for NULL devices,
there may be some places that don't. Rather than fix up all the
possible locations, just require a non-NULL device structure to be
used for allocating/freeing.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
[catalin.marinas@arm.com: s/WARN/WARN_ONCE/]
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Advertise the optional cryptographic and CRC32 instructions to
user space where present. Several hwcap bits [3-7] are allocated.
Signed-off-by: NSteve Capper <steve.capper@linaro.org>
[bit 2 is taken now so use bits 3-7 instead]
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

asm/cputype.h contains a bunch of #defines for CPU id registers
that essentially map to themselves. Remove the #defines and pass
the tokens directly to the inline asm() that reads the registers.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Code referenced in the comment has moved to arch/arm64/kernel/cputable.c
Signed-off-by: NLiviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Make sure the value we are going to return is referenced in order to
avoid warnings from newer GCCs such as:

arch/arm64/include/asm/cmpxchg.h:162:3: warning: value computed is not used [-Wunused-value]
  ((__typeof__(*(ptr)))__cmpxchg_mb((ptr),   \
   ^
net/netfilter/nf_conntrack_core.c:674:2: note: in expansion of macro ‘cmpxchg’
  cmpxchg(&nf_conntrack_hash_rnd, 0, rand);

[Modified to use the current underlying implementation as current
mainline for both cmpxchg() and cmpxchg_local() does -- broonie]
Signed-off-by: NMark Hambleton <mahamble@broadcom.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

AArch64 Single Steping and Breakpoint debug exceptions will be
used by multiple debug framworks like kprobes & kgdb.

This patch implements the hooks for those frameworks to register
their own handlers for handling breakpoint and single step events.

Reworked the debug exception handler in entry.S: do_dbg to route
software breakpoint (BRK64) exception to do_debug_exception()
Signed-off-by: NSandeepa Prabhu <sandeepa.prabhu@linaro.org>
Signed-off-by: NDeepak Saxena <dsaxena@linaro.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

We need at least 24 bytes above frame pointer.
Signed-off-by: NKonstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

get_wchan() is lockless. Task may wakeup at any time and change its own stack,
thus each next stack frame may be overwritten and filled with random stuff.
Signed-off-by: NKonstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

ARMv8 CPUs can perform efficient unaligned memory accesses in hardware
and this feature is relied up on by code such as the dcache
word-at-a-time name hashing.

This patch selects HAVE_EFFICIENT_UNALIGNED_ACCESS for arm64.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

DCACHE_WORD_ACCESS uses the word-at-a-time API for optimised string
comparisons in the vfs layer.

This patch implements support for load_unaligned_zeropad in much the
same way as has been done for ARM, although big-endian systems are also
supported.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

AArch64 instructions must be 4-byte aligned, so make sure this is true
for the futex .fixup section.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch implements the word-at-a-time interface for arm64 using the
same algorithm as ARM. We use the fls64 macro, which expands to a clz
instruction via a compiler builtin. Big-endian configurations make use
of the implementation from asm-generic.

With this implemented, we can replace our byte-at-a-time strnlen_user
and strncpy_from_user functions with the optimised generic versions.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch implements optimised percpu variable accesses using the
el1 r/w thread register (tpidr_el1) along the same lines as arch/arm/.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add support for irq registration when pmu interrupt is percpu.
Signed-off-by: NVinayak Kale <vkale@apm.com>
Signed-off-by: NTuan Phan <tphan@apm.com>
[will: tidied up cross-calling to pass &irq]
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch adds an accessor function for IRQ_PER_CPU flag.
The accessor function is useful to determine whether an IRQ is percpu or not.

This patch is based on an older patch posted by Chris Smith here [1].
There is a minor change w.r.t. Chris's original patch: The accessor function
is renamed as 'irq_is_percpu' instead of 'irq_is_per_cpu'.

[1]: http://lkml.indiana.edu/hypermail/linux/kernel/1207.3/02955.htmlSigned-off-by: NChris Smith <chris.smith@st.com>
Signed-off-by: NVinayak Kale <vkale@apm.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

We currently try to emit .comment twice, once in STABS_DEBUG, and once
in the line immediately following it. As the two section definitions are
identical, the latter is redundant and can be dropped.

This patch drops the redundant .comment section definition.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Describe the virtio device so we can mount disk images in the simulator.

[Reduced the size of the region based on feedback from review -- broonie]
Signed-off-by: NMark Hambleton <mahamble@broadcom.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The definition of virt_addr_valid is that virt_addr_valid should
return true if and only if virt_to_page returns a valid pointer.
The current definition of virt_addr_valid only checks against the
virtual address range. There's no guarantee that just because a
virtual address falls bewteen PAGE_OFFSET and high_memory the
associated physical memory has a valid backing struct page. Follow
the example of other architectures and convert to pfn_valid to
verify that the virtual address is actually valid.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This patch provides a menu for CPU power management options in the
arm64 Kconfig and adds an entry to enable the generic CPU idle configuration.
Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>