Commit Graph

616752 Commits

Author SHA1 Message Date
Mark Rutland 6ba3b554f5 arm64: use alternative auto-nop
Make use of the new alternative_if and alternative_else_nop_endif and
get rid of our homebew NOP sleds, making the code simpler to read.

Note that for cpu_do_switch_mm the ret has been moved out of the
alternative sequence, and in the default case there will be three
additional NOPs executed.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-12 10:46:07 +01:00
Mark Rutland 792d47379f arm64: alternative: add auto-nop infrastructure
In some cases, one side of an alternative sequence is simply a number of
NOPs used to balance the other side. Keeping track of this manually is
tedious, and the presence of large chains of NOPs makes the code more
painful to read than necessary.

To ameliorate matters, this patch adds a new alternative_else_nop_endif,
which automatically balances an alternative sequence with a trivial NOP
sled.

In many cases, we would like a NOP-sled in the default case, and
instructions patched in in the presence of a feature. To enable the NOPs
to be generated automatically for this case, this patch also adds a new
alternative_if, and updates alternative_else and alternative_endif to
work with either alternative_if or alternative_endif.

Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: use new nops macro to generate nop sequences]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-12 10:45:34 +01:00
Will Deacon 05492f2fd8 arm64: lse: convert lse alternatives NOP padding to use __nops
The LSE atomics are implemented using alternative code sequences of
different lengths, and explicit NOP padding is used to ensure the
patching works correctly.

This patch converts the bulk of the LSE code over to using the __nops
macro, which makes it slightly clearer as to what is going on and also
consolidates all of the padding at the end of the various sequences.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 18:12:34 +01:00
Will Deacon f99a250cb6 arm64: barriers: introduce nops and __nops macros for NOP sequences
NOP sequences tend to get used for padding out alternative sections
and uarch-specific pipeline flushes in errata workarounds.

This patch adds macros for generating these sequences as both inline
asm blocks, but also as strings suitable for embedding in other asm
blocks directly.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 18:12:28 +01:00
Will Deacon 8a71f0c656 arm64: sysreg: replace open-coded mrs_s/msr_s with {read,write}_sysreg_s
Similar to our {read,write}_sysreg accessors for architected, named
system registers, this patch introduces {read,write}_sysreg_s variants
that can take arbitrary sys_reg output and therefore access IMPDEF
registers or registers that unsupported by binutils.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 18:12:08 +01:00
Robin Murphy 0e27a7fce6 arm64: Remove shadowed asm-generic headers
We've grown our own versions of bug.h, ftrace.h, pci.h and topology.h,
so generating the generic ones as well is unnecessary and a potential
source of build hiccups. At the very least, having them present has
confused my source-indexing tool, and that simply will not do.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:05:08 +01:00
Suzuki K Poulose 116c81f427 arm64: Work around systems with mismatched cache line sizes
Systems with differing CPU i-cache/d-cache line sizes can cause
problems with the cache management by software when the execution
is migrated from one to another. Usually, the application reads
the cache size on a CPU and then uses that length to perform cache
operations. However, if it gets migrated to another CPU with a smaller
cache line size, things could go completely wrong. To prevent such
cases, always use the smallest cache line size among the CPUs. The
kernel CPU feature infrastructure already keeps track of the safe
value for all CPUID registers including CTR. This patch works around
the problem by :

For kernel, dynamically patch the kernel to read the cache size
from the system wide copy of CTR_EL0.

For applications, trap read accesses to CTR_EL0 (by clearing the SCTLR.UCT)
and emulate the mrs instruction to return the system wide safe value
of CTR_EL0.

For faster access (i.e, avoiding to lookup the system wide value of CTR_EL0
via read_system_reg), we keep track of the pointer to table entry for
CTR_EL0 in the CPU feature infrastructure.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: 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>
2016-09-09 15:03:29 +01:00
Suzuki K Poulose 9dbd5bb25c arm64: Refactor sysinstr exception handling
Right now we trap some of the user space data cache operations
based on a few Errata (ARM 819472, 826319, 827319 and 824069).
We need to trap userspace access to CTR_EL0, if we detect mismatched
cache line size. Since both these traps share the EC, refactor
the handler a little bit to make it a bit more reader friendly.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:29 +01:00
Suzuki K Poulose 072f0a6338 arm64: Introduce raw_{d,i}cache_line_size
On systems with mismatched i/d cache min line sizes, we need to use
the smallest size possible across all CPUs. This will be done by fetching
the system wide safe value from CPU feature infrastructure.
However the some special users(e.g kexec, hibernate) would need the line
size on the CPU (rather than the system wide), when either the system
wide feature may not be accessible or it is guranteed that the caller
executes with a gurantee of no migration.
Provide another helper which will fetch cache line size on the current CPU.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Reviewed-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:29 +01:00
Suzuki K Poulose c831b2ae25 arm64: alternative: Add support for patching adrp instructions
adrp uses PC-relative address offset to a page (of 4K size) of
a symbol. If it appears in an alternative code patched in, we
should adjust the offset to reflect the address where it will
be run from. This patch adds support for fixing the offset
for adrp instructions.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:28 +01:00
Suzuki K Poulose 46084bc253 arm64: insn: Add helpers for adrp offsets
Adds helpers for decoding/encoding the PC relative addresses for adrp.
This will be used for handling dynamic patching of 'adrp' instructions
in alternative code patching.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:28 +01:00
Suzuki K Poulose baa763b565 arm64: alternative: Disallow patching instructions using literals
The alternative code patching doesn't check if the replaced instruction
uses a pc relative literal. This could cause silent corruption in the
instruction stream as the instruction will be executed from a different
address than what it was compiled for. Catch all such cases.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:28 +01:00
Suzuki K Poulose c47a1900ad arm64: Rearrange CPU errata workaround checks
Right now we run through the work around checks on a CPU
from __cpuinfo_store_cpu. There are some problems with that:

1) We initialise the system wide CPU feature registers only after the
Boot CPU updates its cpuinfo. Now, if a work around depends on the
variance of a CPU ID feature (e.g, check for Cache Line size mismatch),
we have no way of performing it cleanly for the boot CPU.

2) It is out of place, invoked from __cpuinfo_store_cpu() in cpuinfo.c. It
is not an obvious place for that.

This patch rearranges the CPU specific capability(aka work around) checks.

1) At the moment we use verify_local_cpu_capabilities() to check if a new
CPU has all the system advertised features. Use this for the secondary CPUs
to perform the work around check. For that we rename
  verify_local_cpu_capabilities() => check_local_cpu_capabilities()
which:

   If the system wide capabilities haven't been initialised (i.e, the CPU
   is activated at the boot), update the system wide detected work arounds.

   Otherwise (i.e a CPU hotplugged in later) verify that this CPU conforms to the
   system wide capabilities.

2) Boot CPU updates the work arounds from smp_prepare_boot_cpu() after we have
initialised the system wide CPU feature values.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: 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>
2016-09-09 15:03:28 +01:00
Suzuki K Poulose 89ba26458b arm64: Use consistent naming for errata handling
This is a cosmetic change to rename the functions dealing with
the errata work arounds to be more consistent with their naming.

1) check_local_cpu_errata() => update_cpu_errata_workarounds()
check_local_cpu_errata() actually updates the system's errata work
arounds. So rename it to reflect the same.

2) verify_local_cpu_errata() => verify_local_cpu_errata_workarounds()
Use errata_workarounds instead of _errata.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:28 +01:00
Suzuki K Poulose ee7bc638f1 arm64: Set the safe value for L1 icache policy
Right now we use 0 as the safe value for CTR_EL0:L1Ip, which is
not defined at the moment. The safer value for the L1Ip should be
the weakest of the policies, which happens to be AIVIVT. While at it,
fix the comment about safe_val.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 15:03:28 +01:00
Zhen Lei 7ba5f605f3 arm64/numa: remove the limitation that cpu0 must bind to node0
1. Remove the old binding code.
2. Read the nid of cpu0 from dts.
3. Fallback the nid of cpu0 to 0 when numa=off is set in bootargs.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:09 +01:00
Zhen Lei df7ffa34cc arm64/numa: remove some useless code
When the deleted code is executed, only the bit of cpu0 was set on
cpu_possible_mask. So that, only set_cpu_numa_node(0, NUMA_NO_NODE); will
be executed. And map_cpu_to_node(0, 0) will soon be called. So these code
can be safely removed.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:09 +01:00
Zhen Lei 7af3a0a992 arm64/numa: support HAVE_SETUP_PER_CPU_AREA
To make each percpu area allocated from its local numa node. Without this
patch, all percpu areas will be allocated from the node which cpu0 belongs
to.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:09 +01:00
Kefeng Wang f11c7bacd5 arm64: numa: Use pr_fmt()
Use pr_fmt to prefix kernel output, and remove duplicated msg
of NUMA turned off.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:09 +01:00
Kefeng Wang ad02180515 of_numa: Use pr_fmt()
Use pr_fmt to prefix kernel output.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:09 +01:00
Kefeng Wang 837dae1b43 of_numa: Use of_get_next_parent to simplify code
Use of_get_next_parent() instead of open-code.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:08 +01:00
Zhen Lei 794224ea56 arm64/numa: avoid inconsistent information to be printed
numa_init may return error because of numa configuration error. So "No
NUMA configuration found" is inaccurate. In fact, specific configuration
error information should be immediately printed by the testing branch.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:08 +01:00
Zhen Lei 9787ed6e5c of/numa: remove a duplicated warning
This warning has been printed in of_numa_parse_cpu_nodes before.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:08 +01:00
Zhen Lei 571a588fec of/numa: add nid check for memory block
If the numa-id which was configured in memory@ devicetree node is greater
than MAX_NUMNODES, we should report a warning. We have done this for cpus
and distance-map dt nodes, this patch help them to be consistent.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:08 +01:00
Zhen Lei 84b14256c1 of/numa: fix a memory@ node can only contains one memory block
For a normal memory@ devicetree node, its reg property can contains more
memory blocks.

Because we don't known how many memory blocks maybe contained, so we try
from index=0, increase 1 until error returned(the end).

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09 14:59:08 +01:00