arm64: Add macros to manage processor debug state

Add macros to enable and disable to manage PSTATE.D
for debugging. The macros local_dbg_save and local_dbg_restore
are moved to irqflags.h file

KGDB boot tests fail because of PSTATE.D is masked.
unmask it for debugging support

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: KGDB: Add Basic KGDB support

Add KGDB debug support for kernel debugging.
With this patch, basic KGDB debugging is possible.GDB register
layout is updated and GDB tool can establish connection with
target and can set/clear breakpoints.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: KGDB: Add step debugging support

Add KGDB software step debugging support for EL1 debug
in AArch64 mode.

KGDB registers step debug handler with debug monitor.
On receiving 'step' command from GDB tool, target enables
software step debugging and step address is updated in ELR.

Software Step debugging is disabled when 'continue' command
is received

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
KGDB: make kgdb_breakpoint() as noinline

The function kgdb_breakpoint() sets up break point at
compile time by calling arch_kgdb_breakpoint();
Though this call is surrounded by wmb() barrier,
the compile can still re-order the break point,
because this scheduling barrier is not a code motion
barrier in gcc.

Making kgdb_breakpoint() as noinline solves this problem
of code reording around break point instruction and also
avoids problem of being called as inline function from
other places

More details about discussion on this can be found here
http://comments.gmane.org/gmane.linux.ports.arm.kernel/269732

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
misc: debug: remove compilation warnings

typecast instruction_pointer macro to unsigned long to
resolve following compiler warnings like
warning: format '%lx' expects argument of type 'long unsigned int',
but argument 2 has type 'u64' [-Wformat]

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: KGDB: Add KGDB config

Add HAVE_ARCH_KGDB for arm64 Kconfig

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: enable processor debug state for secondary cpus

processor debug state PSTATE.D is unmasked in smp call
clear_os_lock for secondary cpus. So debug state is still
masked in normal kernel context.  With this patch, unmask
debug state on secondary boot for the cpus in normal kernel
context. Now kgdb tests passed with multicore.

Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Extend the PCI I/O space to 16MB

The patch moves the PCI I/O space (currently at 64K) before the
earlyprintk mapping and extends it to 16MB.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Convert asm/tlb.h to generic mmu_gather

Over the past couple of years, the generic mmu_gather gained range
tracking - 597e1c3580b7 (mm/mmu_gather: enable tlb flush range in generic
mmu_gather), 2b047252d087 (Fix TLB gather virtual address range
invalidation corner cases) - and tlb_fast_mode() has been removed -
29eb77825cc7 (arch, mm: Remove tlb_fast_mode()).

The new mmu_gather structure is now suitable for arm64 and this patch
converts the arch asm/tlb.h to the generic code. One functional
difference is the shift_arg_pages() case where previously the code was
flushing the full mm (no tlb_start_vma call) but now it flushes the
range given to tlb_gather_mmu() (possibly slightly more efficient
previously).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
arm64: Extend the idmap to the whole kernel image

This patch changes the idmap page table creation during boot to cover
the whole kernel image, allowing functions like cpu_reset() to be safely
called with the physical address.

This patch also simplifies the create_block_map asm macro to no longer
take an idmap argument and always use the phys/virt/end parameters. For
the idmap case, phys == virt.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Fix the soft_restart routine

Change the soft_restart() routine to call cpu_reset() at its identity mapped
physical address.

The cpu_reset() routine must be called at its identity mapped physical address
so that when the MMU is turned off the instruction pointer will be at the correct
location in physical memory.

Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Change misleading function names in dma-mapping

arm64_swiotlb_alloc/free_coherent name can be misleading
somtimes with CMA support being enabled after this
patch (c2104debc235b745265b64d610237a6833fd53)

Change this name to be more generic:
__dma_alloc/free_coherent

Signed-off-by: Ritesh Harjani <ritesh.harjani@gmail.com>
[catalin.marinas@arm.com: renamed arm64_swiotlb_dma_ops to coherent_swiotlb_dma_ops]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: vdso: clean up vdso_pagelist initialization

Remove some unnecessary bits that were apparently carried over from
another architecture's implementation:

- No need to get_page() the vdso text/data - these are part of the
  kernel image.
- No need for ClearPageReserved on the vdso text.
- No need to vmap the first text page to check the ELF header - this
  can be done through &vdso_start.

Also some minor cleanup:
- Use kcalloc for vdso_pagelist array allocation.
- Don't print on allocation failure, slab/slub will do that for us.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Replace ZONE_DMA32 with ZONE_DMA

On arm64 we do not have two DMA zones, so it does not make sense to
implement ZONE_DMA32. This patch changes ZONE_DMA32 with ZONE_DMA, the
latter covering 32-bit dma address space to honour GFP_DMA allocations.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Use swiotlb late initialisation

Since arm64 does not support ISA, there is no need for early swiotlb
initialisation. This patch switches the DMA mapping code to
swiotlb_tlb_late_init_with_default_size(). A side effect of this is that
GFP_DMA is used for the swiotlb buffer and devices with a 32-bit
coherent mask are correctly supported.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Implement coherent DMA API based on swiotlb

This patch adds support for DMA API cache maintenance on SoCs without
hardware device cache coherency.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: remove redundant "psci:" prefixes

Since 652af899799354049b273af897b798b8f03fdd88 "arm64: factor out spin-table
boot method" psci prefix's been introduced. We have a common pr_fmt, so clean
them up.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: remove return value form psci_init()

psci_init() is written to return err code if something goes wrong. However,
the single user, setup_arch(), doesn't care about it. Moreover, every error
path is supplied with a clear message which is enough for pleasant debugging.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
cpufreq: enable ARM drivers on arm64

Enable cpufreq and power kconfig menus on arm64 along with arm cpufreq
drivers. The power menu is needed for OPP support. At least on Calxeda
systems, the same cpufreq driver is used for arm and arm64 based
systems.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: remove unnecessary cache flush at boot

Currently we flush the entire dcache at boot within __cpu_setup, but
this is unnecessary as the booting protocol demands that the dcache is
invalid and off upon entering the kernel. The presence of the cache
flush only serves to hide bugs in bootloaders, and is not safe in the
presence of SMP.

In an SMP boot scenario the CPUs enter coherency outside of the kernel,
and the primary CPU enables its caches before bringing up secondary
CPUs. Therefore if any secondary CPU has an entry in its cache (in
violation of the boot protocol), the primary CPU might snoop it even if
the secondary CPU's cache is disabled. The boot-time cache flush only
serves to hide a firmware bug, and slows down a cpu boot unnecessarily.

This patch removes the unnecessary boot-time cache flush.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: make __flush_dcache_all local only]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>