Commit Graph

74 Commits

Author SHA1 Message Date
Will Deacon
2ce39ad151 arm64: debug: unmask PSTATE.D earlier
Clearing PSTATE.D is one of the requirements for generating a debug
exception. The arm64 booting protocol requires that PSTATE.D is set,
since many of the debug registers (for example, the hw_breakpoint
registers) are UNKNOWN out of reset and could potentially generate
spurious, fatal debug exceptions in early boot code if PSTATE.D was
clear. Once the debug registers have been safely initialised, PSTATE.D
is cleared, however this is currently broken for two reasons:

(1) The boot CPU clears PSTATE.D in a postcore_initcall and secondary
    CPUs clear PSTATE.D in secondary_start_kernel. Since the initcall
    runs after SMP (and the scheduler) have been initialised, there is
    no guarantee that it is actually running on the boot CPU. In this
    case, the boot CPU is left with PSTATE.D set and is not capable of
    generating debug exceptions.

(2) In a preemptible kernel, we may explicitly schedule on the IRQ
    return path to EL1. If an IRQ occurs with PSTATE.D set in the idle
    thread, then we may schedule the kthread_init thread, run the
    postcore_initcall to clear PSTATE.D and then context switch back
    to the idle thread before returning from the IRQ. The exception
    return path will then restore PSTATE.D from the stack, and set it
    again.

This patch fixes the problem by moving the clearing of PSTATE.D earlier
to proc.S. This has the desirable effect of clearing it in one place for
all CPUs, long before we have to worry about the scheduler or any
exception handling. We ensure that the previous reset of MDSCR_EL1 has
completed before unmasking the exception, so that any spurious
exceptions resulting from UNKNOWN debug registers are not generated.

Without this patch applied, the kprobes selftests have been seen to fail
under KVM, where we end up attempting to step the OOL instruction buffer
with PSTATE.D set and therefore fail to complete the step.

Cc: <stable@vger.kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-07-19 16:56:46 +01:00
James Morse
b69e0dc14c arm64: smp: Add function to determine if cpus are stuck in the kernel
kernel/smp.c has a fancy counter that keeps track of the number of CPUs
it marked as not-present and left in cpu_park_loop(). If there are any
CPUs spinning in here, features like kexec or hibernate may release them
by overwriting this memory.

This problem also occurs on machines using spin-tables to release
secondary cores.
After commit 44dbcc93ab ("arm64: Fix behavior of maxcpus=N")
we bring all known cpus into the secondary holding pen, meaning this
memory can't be re-used by kexec or hibernate.

Add a function cpus_are_stuck_in_kernel() to determine if either of these
cases have occurred.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
[catalin.marinas@arm.com: cherry-picked from mainline for kexec dependency]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-27 16:24:51 +01:00
Suzuki K Poulose
99aa036241 arm64: secondary_start_kernel: Remove unnecessary barrier
Remove the unnecessary smp_wmb(), which was added to make sure
that the update_cpu_boot_status() completes before we mark the
CPU online. But update_cpu_boot_status() already has dsb() (required
for the failing CPUs) to ensure the correct behavior.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Dennis Chen <dennis.chen@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-11 10:11:37 +01:00
Suzuki K Poulose
44dbcc93ab arm64: Fix behavior of maxcpus=N
maxcpu=n sets the number of CPUs activated at boot time to a max of n,
but allowing the remaining CPUs to be brought up later if the user
decides to do so. However, on arm64 due to various reasons, we disallowed
hotplugging CPUs beyond n, by marking them not present. Now that
we have checks in place to make sure the hotplugged CPUs have compatible
features with system and requires no new errata, relax the restriction.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-25 15:14:09 +01:00
Jan Glauber
82611c14c4 arm64: Reduce verbosity on SMP CPU stop
When CPUs are stopped during an abnormal operation like panic
for each CPU a line is printed and the stack trace is dumped.

This information is only interesting for the aborting CPU
and on systems with many CPUs it only makes it harder to
debug if after the aborting CPU the log is flooded with data
about all other CPUs too.

Therefore remove the stack dump and printk of other CPUs
and only print a single line that the other CPUs are going to be
stopped and, in case any CPUs remain online list them.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-19 09:53:04 +01:00
Ganapatrao Kulkarni
1a2db30034 arm64, numa: Add NUMA support for arm64 platforms.
Attempt to get the memory and CPU NUMA node via of_numa.  If that
fails, default the dummy NUMA node and map all memory and CPUs to node
0.

Tested-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15 18:06:09 +01:00
Suzuki K Poulose
ac1ad20f9e arm64: vhe: Verify CPU Exception Levels
With a VHE capable CPU, kernel can run at EL2 and is a decided at early
boot. If some of the CPUs didn't start it EL2 or doesn't have VHE, we
could have CPUs running at different exception levels, all in the same
kernel! This patch adds an early check for the secondary CPUs to detect
such situations.

For each non-boot CPU add a sanity check to make sure we don't have
different run levels w.r.t the boot CPU. We save the information on
whether the boot CPU is running in hyp mode or not and ensure the
remaining CPUs match it.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[will: made boot_cpu_hyp_mode static]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-15 18:06:07 +01:00
Linus Torvalds
588ab3f9af arm64 updates for 4.6:
- Initial page table creation reworked to avoid breaking large block
   mappings (huge pages) into smaller ones. The ARM architecture requires
   break-before-make in such cases to avoid TLB conflicts but that's not
   always possible on live page tables
 
 - Kernel virtual memory layout: the kernel image is no longer linked to
   the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of
   the vmalloc space, allowing the kernel to be loaded (nearly) anywhere
   in physical RAM
 
 - Kernel ASLR: position independent kernel Image and modules being
   randomly mapped in the vmalloc space with the randomness is provided
   by UEFI (efi_get_random_bytes() patches merged via the arm64 tree,
   acked by Matt Fleming)
 
 - Implement relative exception tables for arm64, required by KASLR
   (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but
   actual x86 conversion to deferred to 4.7 because of the merge
   dependencies)
 
 - Support for the User Access Override feature of ARMv8.2: this allows
   uaccess functions (get_user etc.) to be implemented using LDTR/STTR
   instructions. Such instructions, when run by the kernel, perform
   unprivileged accesses adding an extra level of protection. The
   set_fs() macro is used to "upgrade" such instruction to privileged
   accesses via the UAO bit
 
 - Half-precision floating point support (part of ARMv8.2)
 
 - Optimisations for CPUs with or without a hardware prefetcher (using
   run-time code patching)
 
 - copy_page performance improvement to deal with 128 bytes at a time
 
 - Sanity checks on the CPU capabilities (via CPUID) to prevent
   incompatible secondary CPUs from being brought up (e.g. weird
   big.LITTLE configurations)
 
 - valid_user_regs() reworked for better sanity check of the sigcontext
   information (restored pstate information)
 
 - ACPI parking protocol implementation
 
 - CONFIG_DEBUG_RODATA enabled by default
 
 - VDSO code marked as read-only
 
 - DEBUG_PAGEALLOC support
 
 - ARCH_HAS_UBSAN_SANITIZE_ALL enabled
 
 - Erratum workaround Cavium ThunderX SoC
 
 - set_pte_at() fix for PROT_NONE mappings
 
 - Code clean-ups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Here are the main arm64 updates for 4.6.  There are some relatively
  intrusive changes to support KASLR, the reworking of the kernel
  virtual memory layout and initial page table creation.

  Summary:

   - Initial page table creation reworked to avoid breaking large block
     mappings (huge pages) into smaller ones.  The ARM architecture
     requires break-before-make in such cases to avoid TLB conflicts but
     that's not always possible on live page tables

   - Kernel virtual memory layout: the kernel image is no longer linked
     to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom
     of the vmalloc space, allowing the kernel to be loaded (nearly)
     anywhere in physical RAM

   - Kernel ASLR: position independent kernel Image and modules being
     randomly mapped in the vmalloc space with the randomness is
     provided by UEFI (efi_get_random_bytes() patches merged via the
     arm64 tree, acked by Matt Fleming)

   - Implement relative exception tables for arm64, required by KASLR
     (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c
     but actual x86 conversion to deferred to 4.7 because of the merge
     dependencies)

   - Support for the User Access Override feature of ARMv8.2: this
     allows uaccess functions (get_user etc.) to be implemented using
     LDTR/STTR instructions.  Such instructions, when run by the kernel,
     perform unprivileged accesses adding an extra level of protection.
     The set_fs() macro is used to "upgrade" such instruction to
     privileged accesses via the UAO bit

   - Half-precision floating point support (part of ARMv8.2)

   - Optimisations for CPUs with or without a hardware prefetcher (using
     run-time code patching)

   - copy_page performance improvement to deal with 128 bytes at a time

   - Sanity checks on the CPU capabilities (via CPUID) to prevent
     incompatible secondary CPUs from being brought up (e.g.  weird
     big.LITTLE configurations)

   - valid_user_regs() reworked for better sanity check of the
     sigcontext information (restored pstate information)

   - ACPI parking protocol implementation

   - CONFIG_DEBUG_RODATA enabled by default

   - VDSO code marked as read-only

   - DEBUG_PAGEALLOC support

   - ARCH_HAS_UBSAN_SANITIZE_ALL enabled

   - Erratum workaround Cavium ThunderX SoC

   - set_pte_at() fix for PROT_NONE mappings

   - Code clean-ups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits)
  arm64: kasan: Fix zero shadow mapping overriding kernel image shadow
  arm64: kasan: Use actual memory node when populating the kernel image shadow
  arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission
  arm64: Fix misspellings in comments.
  arm64: efi: add missing frame pointer assignment
  arm64: make mrs_s prefixing implicit in read_cpuid
  arm64: enable CONFIG_DEBUG_RODATA by default
  arm64: Rework valid_user_regs
  arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly
  arm64: KVM: Move kvm_call_hyp back to its original localtion
  arm64: mm: treat memstart_addr as a signed quantity
  arm64: mm: list kernel sections in order
  arm64: lse: deal with clobbered IP registers after branch via PLT
  arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR
  arm64: kconfig: add submenu for 8.2 architectural features
  arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot
  arm64: Add support for Half precision floating point
  arm64: Remove fixmap include fragility
  arm64: Add workaround for Cavium erratum 27456
  arm64: mm: Mark .rodata as RO
  ...
2016-03-17 20:03:47 -07:00
Thomas Gleixner
fc6d73d674 arch/hotplug: Call into idle with a proper state
Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01 20:36:57 +01:00
Suzuki K Poulose
bb9052744f arm64: Handle early CPU boot failures
A secondary CPU could fail to come online due to insufficient
capabilities and could simply die or loop in the kernel.
e.g, a CPU with no support for the selected kernel PAGE_SIZE
loops in kernel with MMU turned off.
or a hotplugged CPU which doesn't have one of the advertised
system capability will die during the activation.

There is no way to synchronise the status of the failing CPU
back to the master. This patch solves the issue by adding a
field to the secondary_data which can be updated by the failing
CPU. If the secondary CPU fails even before turning the MMU on,
it updates the status in a special variable reserved in the head.txt
section to make sure that the update can be cache invalidated safely
without possible sharing of cache write back granule.

Here are the possible states :

 -1. CPU_MMU_OFF - Initial value set by the master CPU, this value
indicates that the CPU could not turn the MMU on, hence the status
could not be reliably updated in the secondary_data. Instead, the
CPU has updated the status @ __early_cpu_boot_status.

 0. CPU_BOOT_SUCCESS - CPU has booted successfully.

 1. CPU_KILL_ME - CPU has invoked cpu_ops->die, indicating the
master CPU to synchronise by issuing a cpu_ops->cpu_kill.

 2. CPU_STUCK_IN_KERNEL - CPU couldn't invoke die(), instead is
looping in the kernel. This information could be used by say,
kexec to check if it is really safe to do a kexec reboot.

 3. CPU_PANIC_KERNEL - CPU detected some serious issues which
requires kernel to crash immediately. The secondary CPU cannot
call panic() until it has initialised the GIC. This flag can
be used to instruct the master to do so.

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[catalin.marinas@arm.com: conflict resolution]
[catalin.marinas@arm.com: converted "status" from int to long]
[catalin.marinas@arm.com: updated update_early_cpu_boot_status to use str_l]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-25 10:32:23 +00:00
Suzuki K Poulose
fce6361fe9 arm64: Move cpu_die_early to smp.c
This patch moves cpu_die_early to smp.c, where it fits better.
No functional changes, except for adding the necessary checks
for CONFIG_HOTPLUG_CPU.

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24 17:17:45 +00:00
Lorenzo Pieralisi
5e89c55e4e arm64: kernel: implement ACPI parking protocol
The SBBR and ACPI specifications allow ACPI based systems that do not
implement PSCI (eg systems with no EL3) to boot through the ACPI parking
protocol specification[1].

This patch implements the ACPI parking protocol CPU operations, and adds
code that eases parsing the parking protocol data structures to the
ARM64 SMP initializion carried out at the same time as cpus enumeration.

To wake-up the CPUs from the parked state, this patch implements a
wakeup IPI for ARM64 (ie arch_send_wakeup_ipi_mask()) that mirrors the
ARM one, so that a specific IPI is sent for wake-up purpose in order
to distinguish it from other IPI sources.

Given the current ACPI MADT parsing API, the patch implements a glue
layer that helps passing MADT GICC data structure from SMP initialization
code to the parking protocol implementation somewhat overriding the CPU
operations interfaces. This to avoid creating a completely trasparent
DT/ACPI CPU operations layer that would require creating opaque
structure handling for CPUs data (DT represents CPU through DT nodes, ACPI
through static MADT table entries), which seems overkill given that ACPI
on ARM64 mandates only two booting protocols (PSCI and parking protocol),
so there is no need for further protocol additions.

Based on the original work by Mark Salter <msalter@redhat.com>

[1] https://acpica.org/sites/acpica/files/MP%20Startup%20for%20ARM%20platforms.docx

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Loc Ho <lho@apm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Al Stone <ahs3@redhat.com>
[catalin.marinas@arm.com: Added WARN_ONCE(!acpi_parking_protocol_valid() on the IPI]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16 15:12:32 +00:00
Mark Rutland
9e8e865bbe arm64: unify idmap removal
We currently open-code the removal of the idmap and restoration of the
current task's MMU state in a few places.

Before introducing yet more copies of this sequence, unify these to call
a new helper, cpu_uninstall_idmap.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16 15:10:44 +00:00
Jisheng Zhang
29b8302b1a arm64: smp: make of_parse_and_init_cpus static
of_parse_and_init_cpus is only called from within smp.c, so it can be
declared static.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-11-12 15:18:14 +00:00
Suzuki K. Poulose
dbb4e152b8 arm64: Delay cpu feature capability checks
At the moment we run through the arm64_features capability list for
each CPU and set the capability if one of the CPU supports it. This
could be problematic in a heterogeneous system with differing capabilities.
Delay the CPU feature checks until all the enabled CPUs are up(i.e,
smp_cpus_done(), so that we can make better decisions based on the
overall system capability. Once we decide and advertise the capabilities
the alternatives can be applied. From this state, we cannot roll back
a feature to disabled based on the values from a new hotplugged CPU,
due to the runtime patching and other reasons. So, for all new CPUs,
we need to make sure that they have the established system capabilities.
Failing which, we bring the CPU down, preventing it from turning online.
Once the capabilities are decided, any new CPU booting up goes through
verification to ensure that it has all the enabled capabilities and also
invokes the respective enable() method on the CPU.

The CPU errata checks are not delayed and is still executed per-CPU
to detect the respective capabilities. If we ever come across a non-errata
capability that needs to be checked on each-CPU, we could introduce them via
a new capability table(or introduce a flag), which can be processed per CPU.

The next patch will make the feature checks use the system wide
safe value of a feature register.

NOTE: The enable() methods associated with the capability is scheduled
on all the CPUs (which is the only use case at the moment). If we need
a different type of 'enable()' which only needs to be run once on any CPU,
we should be able to handle that when needed.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
[catalin.marinas@arm.com: static variable and coding style fixes]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21 15:35:58 +01:00
Suzuki K. Poulose
4b998ff188 arm64: Delay cpuinfo_store_boot_cpu
At the moment the boot CPU stores the cpuinfo long before the
PERCPU areas are initialised by the kernel. This could be problematic
as the non-boot CPU data structures might get copied with the data
from the boot CPU, giving us no chance to detect if a particular CPU
updated its cpuinfo. This patch delays the boot cpu store to
smp_prepare_boot_cpu().

Also kills the setup_processor() which no longer does meaningful
work.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21 15:33:39 +01:00
Suzuki K. Poulose
3a75578efa arm64: Delay ELF HWCAP initialisation until all CPUs are up
Delay the ELF HWCAP initialisation until all the (enabled) CPUs are
up, i.e, smp_cpus_done(). This is in preparation for detecting the
common features across the CPUS and creating a consistent ELF HWCAP
for the system.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21 15:33:15 +01:00
Suzuki K. Poulose
64f1781897 arm64: Make the CPU information more clear
At early boot, we print the CPU version/revision. On a heterogeneous
system, we could have different types of CPUs. Print the CPU info for
all active cpus. Also, the secondary CPUs prints the message only when
they turn online.

Also, remove the redundant 'revision' information which doesn't
make any sense without the 'variant' field.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21 15:32:47 +01:00
Yang Yingliang
217d453d47 arm64: fix a migrating irq bug when hotplug cpu
When cpu is disabled, all irqs will be migratged to another cpu.
In some cases, a new affinity is different, the old affinity need
to be updated and if irq_set_affinity's return value is IRQ_SET_MASK_OK_DONE,
the old affinity can not be updated. Fix it by using irq_do_set_affinity.

And migrating interrupts is a core code matter, so use the generic
function irq_migrate_all_off_this_cpu() to migrate interrupts in
kernel/irq/migration.c.

Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-09 17:40:35 +01:00
Will Deacon
38d9628750 arm64: mm: kill mm_cpumask usage
mm_cpumask isn't actually used for anything on arm64, so remove all the
code trying to keep it up-to-date.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07 11:56:29 +01:00
Will Deacon
8e63d38876 arm64: flush: use local TLB and I-cache invalidation
There are a number of places where a single CPU is running with a
private page-table and we need to perform maintenance on the TLB and
I-cache in order to ensure correctness, but do not require the operation
to be broadcast to other CPUs.

This patch adds local variants of tlb_flush_all and __flush_icache_all
to support these use-cases and updates the callers respectively.
__local_flush_icache_all also implies an isb, since it is intended to be
used synchronously.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: David Daney <david.daney@cavium.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-07 11:45:27 +01:00
Jonas Rabenstein
377bcff9a3 arm64: remove dead-code depending on CONFIG_UP_LATE_INIT
Commit 4b3dc9679c ("arm64: force CONFIG_SMP=y and remove redundant
and therfore can not be selected anymore.

Remove dead #ifdef-block depending on UP_LATE_INIT in
arch/arm64/kernel/setup.c

Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
[will: kill do_post_cpus_up_work altogether]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-07-29 18:32:09 +01:00
Al Stone
99e3e3ae33 ACPI / ARM64 : use the new BAD_MADT_GICC_ENTRY macro
For those parts of the arm64 ACPI code that need to check GICC subtables
in the MADT, use the new BAD_MADT_GICC_ENTRY macro instead of the previous
BAD_MADT_ENTRY.  The new macro takes into account differences in the size
of the GICC subtable that the old macro did not; this caused failures even
though the subtable entries are valid.

Fixes: aeb823bbac ("ACPICA: ACPI 6.0: Add changes for FADT table.")
Signed-off-by: Al Stone <al.stone@linaro.org>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-07 14:55:04 +01:00
Hanjun Guo
f9058929f2 ARM64 / SMP: Switch pr_err() to pr_debug() for disabled GICC entry
It is normal that firmware presents GICC entry or entries (processors)
with disabled flag in ACPI MADT, taking a system of 16 cpus for example,
ACPI firmware may present 8 ebabled first with another 8 cpus disabled
in MADT, the disabled cpus can be hot-added later.

Firmware may also present more cpus than the hardware actually has, but
disabled the unused ones, and easily enable it when the hardware has such
cpus to make the firmware code scalable.

So that's not an error for disabled cpus in MADT, we can switch pr_err()
to pr_debug() to make the boot a little quieter by default.

Since hwid for disabled cpus often are invalid, and we check invalid hwid
first in the code, for use case that hot add cpus later will be filtered
out and will not be counted in possible cups, so move this check before
the hwid one to prepare the code to count for disabeld cpus when cpu
hot-plug is introduced.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-03 11:48:57 +01:00
Stephen Boyd
be081d9bf3 ARM64: smp: Fix suspicious RCU usage with ipi tracepoints
John Stultz reported an RCU splat on ARM with ipi trace events
enabled. It looks like the same problem exists on ARM64.

At this point in the IPI handling path we haven't called
irq_enter() yet, so RCU doesn't know that we're about to exit
idle and properly warns that we're using RCU from an idle CPU.
Use trace_ipi_entry_rcuidle() instead of trace_ipi_entry() so
that RCU is informed about our exit from idle.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # 3.17+
Fixes: 45ed695ac1 ("ARM64: add IPI tracepoints")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-06-25 14:37:32 +01:00
Catalin Marinas
addc8120a7 Merge branch 'arm64/psci-rework' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux
* 'arm64/psci-rework' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux:
  arm64: psci: remove ACPI coupling
  arm64: psci: kill psci_power_state
  arm64: psci: account for Trusted OS instances
  arm64: psci: support unsigned return values
  arm64: psci: remove unnecessary id indirection
  arm64: smp: consistently use error codes
  arm64: smp_plat: add get_logical_index
  arm/arm64: kvm: add missing PSCI include

Conflicts:
	arch/arm64/kernel/smp.c
2015-06-05 11:21:23 +01:00
Mark Rutland
6b99c68cb5 arm64: smp: consistently use error codes
cpu_kill currently returns one for success and zero for failure, which
is unlike all the other cpu_operations, which return zero for success
and an error code upon failure. This difference is unnecessarily
confusing.

Make cpu_kill consistent with the other cpu_operations.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
2015-05-27 13:21:40 +01:00
Paul E. McKenney
05981277a4 arm64: Use common outgoing-CPU-notification code
This commit removes the open-coded CPU-offline notification with new
common code.  In particular, this change avoids calling scheduler code
using RCU from an offline CPU that RCU is ignoring.  This is a minimal
change.  A more intrusive change might invoke the cpu_check_up_prepare()
and cpu_set_state_online() functions at CPU-online time, which would
allow onlining throw an error if the CPU did not go offline properly.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-21 14:24:26 +01:00
Lorenzo Pieralisi
0f0783365c ARM64: kernel: unify ACPI and DT cpus initialization
The code that initializes cpus on arm64 is currently split in two
different code paths that carry out DT and ACPI cpus initialization.

Most of the code executing SMP initialization is common and should
be merged to reduce discrepancies between ACPI and DT initialization
and to have code initializing cpus in a single common place in the
kernel.

This patch refactors arm64 SMP cpus initialization code to merge
ACPI and DT boot paths in a common file and to create sanity
checks that can be reused by both boot methods.

Current code assumes PSCI is the only available boot method
when arm64 boots with ACPI; this can be easily extended if/when
the ACPI parking protocol is merged into the kernel.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com> [DT]
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-19 16:09:29 +01:00
Lorenzo Pieralisi
819a88263d ARM64: kernel: make cpu_ops hooks DT agnostic
ARM64 CPU operations such as cpu_init and cpu_init_idle take
a struct device_node pointer as a parameter, which corresponds to
the device tree node of the logical cpu on which the operation
has to be applied.

With the advent of ACPI on arm64, where MADT static table entries
are used to initialize cpus, the device tree node parameter
in cpu_ops hooks become useless when booting with ACPI, since
in that case cpu device tree nodes are not present and can not be
used for cpu initialization.

The current cpu_init hook requires a struct device_node pointer
parameter because it is called while parsing the device tree to
initialize CPUs, when the cpu_logical_map (that is used to match
a cpu node reg property to a device tree node) for a given logical
cpu id is not set up yet. This means that the cpu_init hook cannot
rely on the of_get_cpu_node function to retrieve the device tree
node corresponding to the logical cpu id passed in as parameter,
so the cpu device tree node must be passed in as a parameter to fix
this catch-22 dependency cycle.

This patch reshuffles the cpu_logical_map initialization code so
that the cpu_init cpu_ops hook can safely use the of_get_cpu_node
function to retrieve the cpu device tree node, removing the need for
the device tree node pointer parameter.

In the process, the patch removes device tree node parameters
from all cpu_ops hooks, in preparation for SMP DT/ACPI cpus
initialization consolidation.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com> [DT]
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-05-19 16:09:29 +01:00
Linus Torvalds
836ee4874e Initial ACPI support for arm64:
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)
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

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
  ...
2015-04-24 08:23:45 -07:00
Linus Torvalds
6496edfce9 This is the final removal (after several years!) of the obsolete cpus_*
functions, prompted by their mis-use in staging.
 
 With these function removed, all cpu functions should only iterate to
 nr_cpu_ids, so we finally only allocate that many bits when cpumasks
 are allocated offstack.
 
 Thanks,
 Rusty.
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Merge tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull final removal of deprecated cpus_* cpumask functions from Rusty Russell:
 "This is the final removal (after several years!) of the obsolete
  cpus_* functions, prompted by their mis-use in staging.

  With these function removed, all cpu functions should only iterate to
  nr_cpu_ids, so we finally only allocate that many bits when cpumasks
  are allocated offstack"

* tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits)
  cpumask: remove __first_cpu / __next_cpu
  cpumask: resurrect CPU_MASK_CPU0
  linux/cpumask.h: add typechecking to cpumask_test_cpu
  cpumask: only allocate nr_cpumask_bits.
  Fix weird uses of num_online_cpus().
  cpumask: remove deprecated functions.
  mips: fix obsolete cpumask_of_cpu usage.
  x86: fix more deprecated cpu function usage.
  ia64: remove deprecated cpus_ usage.
  powerpc: fix deprecated CPU_MASK_CPU0 usage.
  CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region.
  staging/lustre/o2iblnd: Don't use cpus_weight
  staging/lustre/libcfs: replace deprecated cpus_ calls with cpumask_
  staging/lustre/ptlrpc: Do not use deprecated cpus_* functions
  blackfin: fix up obsolete cpu function usage.
  parisc: fix up obsolete cpu function usage.
  tile: fix up obsolete cpu function usage.
  arm64: fix up obsolete cpu function usage.
  mips: fix up obsolete cpu function usage.
  x86: fix up obsolete cpu function usage.
  ...
2015-04-20 10:19:03 -07:00
Hanjun Guo
fccb9a81fd ARM64 / ACPI: Parse MADT for SMP initialization
MADT contains the information for MPIDR which is essential for
SMP initialization, parse the GIC cpu interface structures to
get the MPIDR value and map it to cpu_logical_map(), and add
enabled cpu with valid MPIDR into cpu_possible_map.

ACPI 5.1 only has two explicit methods to boot up SMP, PSCI and
Parking protocol, but the Parking protocol is only specified for
ARMv7 now, so make PSCI as the only way for the SMP boot protocol
before some updates for the ACPI spec or the Parking protocol spec.

Parking protocol patches for SMP boot will be sent to upstream when
the new version of Parking protocol is ready.

CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Mark Rutland <mark.rutland@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>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-25 11:52:42 +00:00
Ard Biesheuvel
dd006da216 arm64: mm: increase VA range of identity map
The page size and the number of translation levels, and hence the supported
virtual address range, are build-time configurables on arm64 whose optimal
values are use case dependent. However, in the current implementation, if
the system's RAM is located at a very high offset, the virtual address range
needs to reflect that merely because the identity mapping, which is only used
to enable or disable the MMU, requires the extended virtual range to map the
physical memory at an equal virtual offset.

This patch relaxes that requirement, by increasing the number of translation
levels for the identity mapping only, and only when actually needed, i.e.,
when system RAM's offset is found to be out of reach at runtime.

Tested-by: Laura Abbott <lauraa@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-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>
2015-03-23 11:35:29 +00:00
Mark Rutland
137650aad9 arm64: apply alternatives for !SMP kernels
Currently we only perform alternative patching for kernels built with
CONFIG_SMP, as we call apply_alternatives_all() in smp.c, which is only
built for CONFIG_SMP. Thus !SMP kernels may not have necessary
alternatives patched in.

This patch ensures that we call apply_alternatives_all() once all CPUs
are booted, even for !SMP kernels, by having the smp_init_cpus() stub
call this for !SMP kernels via up_late_init. A new wrapper,
do_post_cpus_up_work, is added so we can hook other calls here later
(e.g. boot mode logging).

Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Fixes: e039ee4ee3 ("arm64: add alternative runtime patching")
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-17 16:58:24 +00:00
Rusty Russell
434ed7f4b0 arm64: fix up obsolete cpu function usage.
Thanks to spatch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
2015-03-05 15:25:06 +10:30
Jiang Liu
0aaf0dae81 smp, ARM64: Kill SMP single function call interrupt
Commit 9a46ad6d6d "smp: make smp_call_function_many() use logic
similar to smp_call_function_single()" has unified the way to handle
single and multiple cross-CPU function calls. Now only one interrupt
is needed for architecture specific code to support generic SMP function
call interfaces, so kill the redundant single function call interrupt.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-23 18:06:47 +00:00
Andre Przywara
932ded4b0b arm64: add module support for alternatives fixups
Currently the kernel patches all necessary instructions once at boot
time, so modules are not covered by this.
Change the apply_alternatives() function to take a beginning and an
end pointer and introduce a new variant (apply_alternatives_all()) to
cover the existing use case for the static kernel image section.
Add a module_finalize() function to arm64 to check for an
alternatives section in a module and patch only the instructions from
that specific area.
Since that module code is not touched before the module
initialization has ended, we don't need to halt the machine before
doing the patching in the module's code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-04 10:28:24 +00:00
Andre Przywara
e039ee4ee3 arm64: add alternative runtime patching
With a blatant copy of some x86 bits we introduce the alternative
runtime patching "framework" to arm64.
This is quite basic for now and we only provide the functions we need
at this time.
This is connected to the newly introduced feature bits.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25 13:46:36 +00:00
Frederic Weisbecker
3631073659 arm64: Tell irq work about self IPI support
ARM64 irq work self-IPI support depends on __smp_cross_call to point to
some relevant IRQ controller operations. This information should be
available after the call to init_IRQ().

Lets implement arch_irq_work_has_interrupt() accordingly.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-09-13 18:46:13 +02:00
Linus Torvalds
c23190c0bf Nicolas Pitre added generic tracepoints for tracing IPIs and updated the
arm and arm64 architectures. It required some minor updates to the generic
 tracepoint system, so it had to wait for me to implement them.
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Merge tag 'trace-ipi-tracepoints' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull IPI tracepoints for ARM from Steven Rostedt:
 "Nicolas Pitre added generic tracepoints for tracing IPIs and updated
  the arm and arm64 architectures.  It required some minor updates to
  the generic tracepoint system, so it had to wait for me to implement
  them"

* tag 'trace-ipi-tracepoints' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ARM64: add IPI tracepoints
  ARM: add IPI tracepoints
  tracepoint: add generic tracepoint definitions for IPI tracing
  tracing: Do not do anything special with tracepoint_string when tracing is disabled
2014-08-09 17:33:44 -07:00
Nicolas Pitre
45ed695ac1 ARM64: add IPI tracepoints
The strings used to list IPIs in /proc/interrupts are reused for tracing
purposes.

While at it, the code is slightly cleaned up so the ipi_types array
indices are no longer offset by IPI_RESCHEDULE whose value is 0 anyway.

Link: http://lkml.kernel.org/p/1406318733-26754-5-git-send-email-nicolas.pitre@linaro.org

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-08-07 20:40:42 -04:00
Mark Rutland
df857416a1 arm64: cpuinfo: record cpu system register values
Several kernel subsystems need to know details about CPU system register
values, sometimes for CPUs other than that they are executing on. Rather
than hard-coding system register accesses and cross-calls for these
cases, this patch adds logic to record various system register values at
boot-time. This may be used for feature reporting, firmware bug
detection, etc.

Separate hooks are added for the boot and hotplug paths to enable
one-time intialisation and cold/warm boot value mismatch detection in
later patches.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-18 15:24:09 +01:00
Linus Torvalds
cc07aabc53 - Optimised assembly string/memory routines (based on the AArch64 Cortex
Strings library contributed to glibc but re-licensed under GPLv2)
 - Optimised crypto algorithms making use of the ARMv8 crypto extensions
   (together with kernel API for using FPSIMD instructions in interrupt
   context)
 - Ftrace support
 - CPU topology parsing from DT
 - ESR_EL1 (Exception Syndrome Register) exposed to user space signal
   handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
 - 1GB section linear mapping if applicable
 - Barriers usage clean-up
 - Default pgprot clean-up
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into next

Pull arm64 updates from Catalin Marinas:
 - Optimised assembly string/memory routines (based on the AArch64
   Cortex Strings library contributed to glibc but re-licensed under
   GPLv2)
 - Optimised crypto algorithms making use of the ARMv8 crypto extensions
   (together with kernel API for using FPSIMD instructions in interrupt
   context)
 - Ftrace support
 - CPU topology parsing from DT
 - ESR_EL1 (Exception Syndrome Register) exposed to user space signal
   handlers for SIGSEGV/SIGBUS (useful to emulation tools like Qemu)
 - 1GB section linear mapping if applicable
 - Barriers usage clean-up
 - Default pgprot clean-up

Conflicts as per Catalin.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (57 commits)
  arm64: kernel: initialize broadcast hrtimer based clock event device
  arm64: ftrace: Add system call tracepoint
  arm64: ftrace: Add CALLER_ADDRx macros
  arm64: ftrace: Add dynamic ftrace support
  arm64: Add ftrace support
  ftrace: Add arm64 support to recordmcount
  arm64: Add 'notrace' attribute to unwind_frame() for ftrace
  arm64: add __ASSEMBLY__ in asm/insn.h
  arm64: Fix linker script entry point
  arm64: lib: Implement optimized string length routines
  arm64: lib: Implement optimized string compare routines
  arm64: lib: Implement optimized memcmp routine
  arm64: lib: Implement optimized memset routine
  arm64: lib: Implement optimized memmove routine
  arm64: lib: Implement optimized memcpy routine
  arm64: defconfig: enable a few more common/useful options in defconfig
  ftrace: Make CALLER_ADDRx macros more generic
  arm64: Fix deadlock scenario with smp_send_stop()
  arm64: Fix machine_shutdown() definition
  arm64: Support arch_irq_work_raise() via self IPIs
  ...
2014-06-06 10:43:28 -07:00
Larry Bassel
eb631bb5bf arm64: Support arch_irq_work_raise() via self IPIs
Support for arch_irq_work_raise() was missing from
arm64 (a prerequisite for FULL_NOHZ).

This patch is based on the arm32 patch ARM 7872/1.

commit bf18525fd7
Author: Stephen Boyd <sboyd@codeaurora.org>
Date:   Tue Oct 29 20:32:56 2013 +0100

    ARM: 7872/1: Support arch_irq_work_raise() via self IPIs

    By default, IRQ work is run from the tick interrupt (see
    irq_work_run() in update_process_times()). When we're in full
    NOHZ mode, restarting the tick requires the use of IRQ work and
    if the only place we run IRQ work is in the tick interrupt we
    have an unbreakable cycle. Implement arch_irq_work_raise() via
    self IPIs to break this cycle and get the tick started again.
    Note that we implement this via IPIs which are only available on
    SMP builds. This shouldn't be a problem because full NOHZ is only
    supported on SMP builds anyway.

    Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
    Reviewed-by: Kevin Hilman <khilman@linaro.org>
    Cc: Frederic Weisbecker <fweisbec@gmail.com>
    Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: Larry Bassel <larry.bassel@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-16 17:42:21 +01:00
Ashwin Chaugule
c814ca029e ARM: Check if a CPU has gone offline
PSCIv0.2 adds a new function called AFFINITY_INFO, which
can be used to query if a specified CPU has actually gone
offline. Calling this function via cpu_kill ensures that
a CPU has quiesced after a call to cpu_die. This helps
prevent the CPU from doing arbitrary bad things when data
or instructions are clobbered (as happens with kexec)
in the window between a CPU announcing that it is dead
and said CPU leaving the kernel.

Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
2014-05-15 10:16:30 -04:00
Mark Brown
f6e763b93a arm64: topology: Implement basic CPU topology support
Add basic CPU topology support to arm64, based on the existing pre-v8
code and some work done by Mark Hambleton.  This patch does not
implement any topology discovery support since that should be based on
information from firmware, it merely implements the scaffolding for
integration of topology support in the architecture.

No locking of the topology data is done since it is only modified during
CPU bringup with external serialisation from the SMP code.

The goal is to separate the architecture hookup for providing topology
information from the DT parsing in order to ease review and avoid
blocking the architecture code (which will be built on by other work)
with the DT code review by providing something simple and basic.

Following patches will implement support for interpreting topology
information from MPIDR and for parsing the DT topology bindings for ARM,
similar patches will be needed for ACPI.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
[catalin.marinas@arm.com: removed CONFIG_CPU_TOPOLOGY, always on if SMP]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-03-04 10:30:07 +00:00
Vijaya Kumar K
d8ed442a00 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>
2014-02-26 11:16:27 +00:00
Nicolas Pitre
f864b61ee4 arm64: FIQs are unused
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: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-01-30 13:51:43 +00:00
Catalin Marinas
0a5be743e8 Merge tag 'arm64-suspend' of git://linux-arm.org/linux-2.6-lp into upstream
* 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
2013-12-19 17:57:51 +00:00