Commit 4b3dc9679cf7 ("arm64: force CONFIG_SMP=y and remove redundant
#ifdefs") incorrectly resolved a conflict on arch/arm64/kernel/Makefile
which resulted in a partial revert of 52da443ec4d0 ("arm64: perf: factor
out callchain code"), leading to perf_callchain.o depending on
CONFIG_HW_PERF_EVENTS instead of CONFIG_PERF_EVENTS.

This patch restores the kconfig dependency for perf_callchain.o.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Commit 4b3dc9679cf7 ("arm64: force CONFIG_SMP=y and remove redundant
#ifdefs") forces SMP on arm64. To build the necessary objects for SMP,
they were added to the arm64-obj-y rule in arch/arm64/kernel/Makefile,
without removing the arm64-obj-$(CONFIG_SMP) rule.

Remove redundant object file list depending on always-yes CONFIG_SMP in
arch/arm64/kernel/Makefile.

Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Nobody seems to be producing !SMP systems anymore, so this is just
becoming a source of kernel bugs, particularly if people want to use
coherent DMA with non-shared pages.

This patch forces CONFIG_SMP=y for arm64, removing a modest amount of
code in the process.

Signed-off-by: Will Deacon <will.deacon@arm.com>

We currently bundle the callchain handling code with the PMU code,
despite the fact the two are distinct, and the former can be useful even
in the absence of the latter.

Follow the example of arch/arm and factor the callchain handling into
its own file dependent on CONFIG_PERF_EVENTS rather than
CONFIG_HW_PERF_EVENTS.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

Pull initial ACPI support for arm64 from Will Deacon:
 "This series introduces preliminary ACPI 5.1 support to the arm64
  kernel using the "hardware reduced" profile.  We don't support any
  peripherals yet, so it's fairly limited in scope:

   - MEMORY init (UEFI)

   - ACPI discovery (RSDP via UEFI)

   - CPU init (FADT)

   - GIC init (MADT)

   - SMP boot (MADT + PSCI)

   - ACPI Kconfig options (dependent on EXPERT)

  ACPI for arm64 has been in development for a while now and hardware
  has been available that can boot with either FDT or ACPI tables.  This
  has been made possible by both changes to the ACPI spec to cater for
  ARM-based machines (known as "hardware-reduced" in ACPI parlance) but
  also a Linaro-driven effort to get this supported on top of the Linux
  kernel.  This pull request is the result of that work.

  These changes allow us to initialise the CPUs, interrupt controller,
  and timers via ACPI tables, with memory information and cmdline coming
  from EFI.  We don't support a hybrid ACPI/FDT scheme.  Of course,
  there is still plenty of work to do (a serial console would be nice!)
  but I expect that to happen on a per-driver basis after this core
  series has been merged.

  Anyway, the diff stat here is fairly horrible, but splitting this up
  and merging it via all the different subsystems would have been
  extremely painful.  Instead, we've got all the relevant Acks in place
  and I've not seen anything other than trivial (Kconfig) conflicts in
  -next (for completeness, I've included my resolution below).  Nearly
  half of the insertions fall under Documentation/.

  So, we'll see how this goes.  Right now, it all depends on EXPERT and
  I fully expect people to use FDT by default for the immediate future"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (31 commits)
  ARM64 / ACPI: make acpi_map_gic_cpu_interface() as void function
  ARM64 / ACPI: Ignore the return error value of acpi_map_gic_cpu_interface()
  ARM64 / ACPI: fix usage of acpi_map_gic_cpu_interface
  ARM64: kernel: acpi: honour acpi=force command line parameter
  ARM64: kernel: acpi: refactor ACPI tables init and checks
  ARM64: kernel: psci: let ACPI probe PSCI version
  ARM64: kernel: psci: factor out probe function
  ACPI: move arm64 GSI IRQ model to generic GSI IRQ layer
  ARM64 / ACPI: Don't unflatten device tree if acpi=force is passed
  ARM64 / ACPI: additions of ACPI documentation for arm64
  Documentation: ACPI for ARM64
  ARM64 / ACPI: Enable ARM64 in Kconfig
  XEN / ACPI: Make XEN ACPI depend on X86
  ARM64 / ACPI: Select ACPI_REDUCED_HARDWARE_ONLY if ACPI is enabled on ARM64
  clocksource / arch_timer: Parse GTDT to initialize arch timer
  irqchip: Add GICv2 specific ACPI boot support
  ARM64 / ACPI: Introduce ACPI_IRQ_MODEL_GIC and register device's gsi
  ACPI / processor: Make it possible to get CPU hardware ID via GICC
  ACPI / processor: Introduce phys_cpuid_t for CPU hardware ID
  ARM64 / ACPI: Parse MADT for SMP initialization
  ...

As we detect more architectural features at runtime, it makes
sense to reuse the existing framework whilst avoiding to call
a feature an erratum...

This patch extract the core capability parsing, moves it into
a new file (cpufeature.c), and let the CPU errata detection code
use it.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

As we want to get ACPI tables to parse and then use the information
for system initialization, we should get the RSDP (Root System
Description Pointer) first, it then locates Extended Root Description
Table (XSDT) which contains all the 64-bit physical address that
pointer to other boot-time tables.

Introduce acpi.c and its related head file in this patch to provide
fundamental needs of extern variables and functions for ACPI core,
and then get boot-time tables as needed.
  - asm/acenv.h for arch specific ACPICA environments and
    implementation, It is needed unconditionally by ACPI core;
  - asm/acpi.h for arch specific variables and functions needed by
    ACPI driver core;
  - acpi.c for ARM64 related ACPI implementation for ACPI driver
    core;

acpi_boot_table_init() is introduced to get RSDP and boot-time tables,
it will be called in setup_arch() before paging_init(), so we should
use eary_memremap() mechanism here to get the RSDP and all the table
pointers.

FADT Major.Minor version was introduced in ACPI 5.1, it is the same
as ACPI version.

In ACPI 5.1, some major gaps are fixed for ARM, such as updates in
MADT table for GIC and SMP init, without those updates, we can not
get the MPIDR for SMP init, and GICv2/3 related init information, so
we can't boot arm64 ACPI properly with table versions predating 5.1.

If firmware provides ACPI tables with ACPI version less than 5.1,
OS has no way to retrieve the configuration data that is necessary
to init SMP boot protocol and the GIC properly, so disable ACPI if
we get an FADT table with version less that 5.1 when acpi_boot_table_init()
called.

CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Tested-by: Yijing Wang <wangyijing@huawei.com>
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
Tested-by: Timur Tabi <timur@codeaurora.org>
Tested-by: Robert Richter <rrichter@cavium.com>
Acked-by: Robert Richter <rrichter@cavium.com>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

struct cpu_table is an artifact left from the (very) early days of
the arm64 port, and its only real use is to allow the most beautiful
"AArch64 Processor" string to be displayed at boot time.

Really? Yes, really.

Let's get rid of it. In order to avoid another BogoMips-gate, the
aforementioned string is preserved.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

An arm64 allmodconfig fails to build with GCC 5 due to __asmeq
assertions in the PSCI firmware calling code firing due to mcount
preambles breaking our assumptions about register allocation of function
arguments:

  /tmp/ccDqJsJ6.s: Assembler messages:
  /tmp/ccDqJsJ6.s:60: Error: .err encountered
  /tmp/ccDqJsJ6.s:61: Error: .err encountered
  /tmp/ccDqJsJ6.s:62: Error: .err encountered
  /tmp/ccDqJsJ6.s:99: Error: .err encountered
  /tmp/ccDqJsJ6.s:100: Error: .err encountered
  /tmp/ccDqJsJ6.s:101: Error: .err encountered

This patch fixes the issue by moving the PSCI calls out-of-line into
their own assembly files, which are safe from the compiler's meddling
fingers.

Reported-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

ARM64_CPU_SUSPEND config option was introduced to make code providing
context save/restore selectable only on platforms requiring power
management capabilities.

Currently ARM64_CPU_SUSPEND depends on the PM_SLEEP config option which
in turn is set by the SUSPEND config option.

The introduction of CPU_IDLE for arm64 requires that code configured
by ARM64_CPU_SUSPEND (context save/restore) should be compiled in
in order to enable the CPU idle driver to rely on CPU operations
carrying out context save/restore.

The ARM64_CPUIDLE config option (ARM64 generic idle driver) is therefore
forced to select ARM64_CPU_SUSPEND, even if there may be (ie PM_SLEEP)
failed dependencies, which is not a clean way of handling the kernel
configuration option.

For these reasons, this patch removes the ARM64_CPU_SUSPEND config option
and makes the context save/restore dependent on CPU_PM, which is selected
whenever either SUSPEND or CPU_IDLE are configured, cleaning up dependencies
in the process.

This way, code previously configured through ARM64_CPU_SUSPEND is
compiled in whenever a power management subsystem requires it to be
present in the kernel (SUSPEND || CPU_IDLE), which is the behaviour
expected on ARM64 kernels.

The cpu_suspend and cpu_init_idle CPU operations are added only if
CPU_IDLE is selected, since they are CPU_IDLE specific methods and
should be grouped and defined accordingly.

PSCI CPU operations are updated to reflect the introduced changes.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>