linux.git/Documentation/arm64, branch v4.4 Linux kernel source tree Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 2015-11-04T22:47:13+00:00 Linus Torvalds torvalds@linux-foundation.org 2015-11-04T22:47:13+00:00 2dc10ad81fc017837037e60439662e1b16bdffb9 Pull arm64 updates from Catalin Marinas: - "genirq: Introduce generic irq migration for cpu hotunplugged" patch merged from tip/irq/for-arm to allow the arm64-specific part to be upstreamed via the arm64 tree - CPU feature detection reworked to cope with heterogeneous systems where CPUs may not have exactly the same features. The features reported by the kernel via internal data structures or ELF_HWCAP are delayed until all the CPUs are up (and before user space starts) - Support for 16KB pages, with the additional bonus of a 36-bit VA space, though the latter only depending on EXPERT - Implement native {relaxed, acquire, release} atomics for arm64 - New ASID allocation algorithm which avoids IPI on roll-over, together with TLB invalidation optimisations (using local vs global where feasible) - KASan support for arm64 - EFI_STUB clean-up and isolation for the kernel proper (required by KASan) - copy_{to,from,in}_user optimisations (sharing the memcpy template) - perf: moving arm64 to the arm32/64 shared PMU framework - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware - Support for the contiguous PTE hint on kernel mapping (16 consecutive entries may be able to use a single TLB entry) - Generic CONFIG_HZ now used on arm64 - defconfig updates * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits) arm64/efi: fix libstub build under CONFIG_MODVERSIONS ARM64: Enable multi-core scheduler support by default arm64/efi: move arm64 specific stub C code to libstub arm64: page-align sections for DEBUG_RODATA arm64: Fix build with CONFIG_ZONE_DMA=n arm64: Fix compat register mappings arm64: Increase the max granular size arm64: remove bogus TASK_SIZE_64 check arm64: make Timer Interrupt Frequency selectable arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED arm64: cachetype: fix definitions of ICACHEF_* flags arm64: cpufeature: declare enable_cpu_capabilities as static genirq: Make the cpuhotplug migration code less noisy arm64: Constify hwcap name string arrays arm64/kvm: Make use of the system wide safe values arm64/debug: Make use of the system wide safe value arm64: Move FP/ASIMD hwcap handling to common code arm64/HWCAP: Use system wide safe values arm64/capabilities: Make use of system wide safe value arm64: Delay cpu feature capability checks ... 
Pull arm64 updates from Catalin Marinas:

 - "genirq: Introduce generic irq migration for cpu hotunplugged" patch
   merged from tip/irq/for-arm to allow the arm64-specific part to be
   upstreamed via the arm64 tree

 - CPU feature detection reworked to cope with heterogeneous systems
   where CPUs may not have exactly the same features.  The features
   reported by the kernel via internal data structures or ELF_HWCAP are
   delayed until all the CPUs are up (and before user space starts)

 - Support for 16KB pages, with the additional bonus of a 36-bit VA
   space, though the latter only depending on EXPERT

 - Implement native {relaxed, acquire, release} atomics for arm64

 - New ASID allocation algorithm which avoids IPI on roll-over, together
   with TLB invalidation optimisations (using local vs global where
   feasible)

 - KASan support for arm64

 - EFI_STUB clean-up and isolation for the kernel proper (required by
   KASan)

 - copy_{to,from,in}_user optimisations (sharing the memcpy template)

 - perf: moving arm64 to the arm32/64 shared PMU framework

 - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware

 - Support for the contiguous PTE hint on kernel mapping (16 consecutive
   entries may be able to use a single TLB entry)

 - Generic CONFIG_HZ now used on arm64

 - defconfig updates

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits)
  arm64/efi: fix libstub build under CONFIG_MODVERSIONS
  ARM64: Enable multi-core scheduler support by default
  arm64/efi: move arm64 specific stub C code to libstub
  arm64: page-align sections for DEBUG_RODATA
  arm64: Fix build with CONFIG_ZONE_DMA=n
  arm64: Fix compat register mappings
  arm64: Increase the max granular size
  arm64: remove bogus TASK_SIZE_64 check
  arm64: make Timer Interrupt Frequency selectable
  arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED
  arm64: cachetype: fix definitions of ICACHEF_* flags
  arm64: cpufeature: declare enable_cpu_capabilities as static
  genirq: Make the cpuhotplug migration code less noisy
  arm64: Constify hwcap name string arrays
  arm64/kvm: Make use of the system wide safe values
  arm64/debug: Make use of the system wide safe value
  arm64: Move FP/ASIMD hwcap handling to common code
  arm64/HWCAP: Use system wide safe values
  arm64/capabilities: Make use of system wide safe value
  arm64: Delay cpu feature capability checks
  ...
arm64: Add page size to the kernel image header 2015-10-19T16:54:41+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2015-10-19T13:19:36+00:00 9d372c9fab34cd8803141871195141995f85c7f7 This patch adds the page size to the arm64 kernel image header so that one can infer the PAGESIZE used by the kernel. This will be helpful to diagnose failures to boot the kernel with page size not supported by the CPU. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
This patch adds the page size to the arm64 kernel image header
so that one can infer the PAGESIZE used by the kernel. This will
be helpful to diagnose failures to boot the kernel with page size
not supported by the CPU.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Update booting requirements for GICv3 in GICv2 mode 2015-10-09T21:16:57+00:00 Marc Zyngier marc.zyngier@arm.com 2015-09-30T11:05:17+00:00 6d32ab2d8a982ffd46c4dcad9739292f57bc26de The current requirements do not describe the case where a GICv3 system gets booted with system register access disabled, and expect the kernel to drive GICv3 in GICv2 mode. Describe the expected settings for that particular case. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> 
The current requirements do not describe the case where a GICv3
system gets booted with system register access disabled, and
expect the kernel to drive GICv3 in GICv2 mode.

Describe the expected settings for that particular case.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
arm64/Documentation: clarify wording regarding memory below the Image 2015-07-29T17:32:10+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2015-07-29T11:30:39+00:00 6c020ea8dc3a8adee81b6f141428a7a75249706e Clarify that the memory below the start of the image but inside the region covered by the linear mapping has no special significance to the kernel, and may be used by the firmware provided that it is marked as reserved. Also, fix up some whitespace errors. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
Clarify that the memory below the start of the image but inside the
region covered by the linear mapping has no special significance to
the kernel, and may be used by the firmware provided that it is marked
as reserved.

Also, fix up some whitespace errors.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: use fixmap region for permanent FDT mapping 2015-06-02T15:31:33+00:00 Ard Biesheuvel ard.biesheuvel@linaro.org 2015-06-01T11:40:32+00:00 61bd93ce801bb6df36eda257a9d2d16c02863cdd Currently, the FDT blob needs to be in the same 512 MB region as the kernel, so that it can be mapped into the kernel virtual memory space very early on using a minimal set of statically allocated translation tables. Now that we have early fixmap support, we can relax this restriction, by moving the permanent FDT mapping to the fixmap region instead. This way, the FDT blob may be anywhere in memory. This also moves the vetting of the FDT to mmu.c, since the early init code in head.S does not handle mapping of the FDT anymore. At the same time, fix up some comments in head.S that have gone stale. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Currently, the FDT blob needs to be in the same 512 MB region as
the kernel, so that it can be mapped into the kernel virtual memory
space very early on using a minimal set of statically allocated
translation tables.

Now that we have early fixmap support, we can relax this restriction,
by moving the permanent FDT mapping to the fixmap region instead.
This way, the FDT blob may be anywhere in memory.

This also moves the vetting of the FDT to mmu.c, since the early
init code in head.S does not handle mapping of the FDT anymore.
At the same time, fix up some comments in head.S that have gone stale.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
ARM64 / ACPI: additions of ACPI documentation for arm64 2015-03-26T15:13:09+00:00 Al Stone al.stone@linaro.org 2015-03-24T14:02:55+00:00 735f00bdf23c427af0f54a9e672a93b5d3723f60 One more documentation file are also being added: A section by section review of the ACPI spec (acpi_object_usage.txt) to note recommendations and prohibitions on the use of the numerous ACPI tables and objects. This sets out the current expectations of the firmware by Linux very explicitly (or as explicitly as I can, for now). CC: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> CC: Yi Li <phoenix.liyi@huawei.com> CC: Mark Langsdorf <mlangsdo@redhat.com> CC: Ashwin Chaugule <ashwinc@codeaurora.org> Acked-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
One more documentation file are also being added:

A section by section review of the ACPI spec (acpi_object_usage.txt)
to note recommendations and prohibitions on the use of the numerous
ACPI tables and objects.  This sets out the current expectations of
the firmware by Linux very explicitly (or as explicitly as I can, for
now).

CC: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
CC: Yi Li <phoenix.liyi@huawei.com>
CC: Mark Langsdorf <mlangsdo@redhat.com>
CC: Ashwin Chaugule <ashwinc@codeaurora.org>
Acked-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Documentation: ACPI for ARM64 2015-03-26T15:13:09+00:00 Graeme Gregory graeme.gregory@linaro.org 2015-03-24T14:02:54+00:00 dc81f2cfaa7f536e9900080cdc63e403440b670b Add documentation for the guidelines of how to use ACPI on ARM64. Reviewed-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Reviewed-by: Yi Li <phoenix.liyi@huawei.com> Reviewed-by: Mark Langsdorf <mlangsdo@redhat.com> Reviewed-by: Ashwin Chaugule <ashwinc@codeaurora.org> Acked-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org> Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 
Add documentation for the guidelines of how to use ACPI
on ARM64.

Reviewed-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Reviewed-by: Yi Li <phoenix.liyi@huawei.com>
Reviewed-by: Mark Langsdorf <mlangsdo@redhat.com>
Reviewed-by: Ashwin Chaugule <ashwinc@codeaurora.org>
Acked-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Al Stone <al.stone@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: Emulate SETEND for AArch32 tasks 2015-01-23T17:11:44+00:00 Suzuki K. Poulose suzuki.poulose@arm.com 2015-01-21T12:43:11+00:00 2d888f48e056119495847a269a435d5c3d9df349 Emulate deprecated 'setend' instruction for AArch32 bit tasks. setend [le/be] - Sets the endianness of EL0 On systems with CPUs which support mixed endian at EL0, the hardware support for the instruction can be enabled by setting the SCTLR_EL1.SED bit. Like the other emulated instructions it is controlled by an entry in /proc/sys/abi/. For more information see : Documentation/arm64/legacy_instructions.txt The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which will be reflected in the PSTATE.E in AArch32 context. This patch also restores the native endianness for the execution of signal handlers, since the process could have changed the endianness. Note: All CPUs on the system must have mixed endian support at EL0. Once the handler is registered, hotplugging a CPU which doesn't support mixed endian, could lead to unexpected results/behavior in applications. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> 
Emulate deprecated 'setend' instruction for AArch32 bit tasks.

	setend [le/be] - Sets the endianness of EL0

On systems with CPUs which support mixed endian at EL0, the hardware
support for the instruction can be enabled by setting the SCTLR_EL1.SED
bit. Like the other emulated instructions it is controlled by an entry in
/proc/sys/abi/. For more information see :
	Documentation/arm64/legacy_instructions.txt

The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which
will be reflected in the PSTATE.E in AArch32 context.

This patch also restores the native endianness for the execution of signal
handlers, since the process could have changed the endianness.

Note: All CPUs on the system must have mixed endian support at EL0. Once the
handler is registered, hotplugging a CPU which doesn't support mixed endian,
could lead to unexpected results/behavior in applications.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: Emulate CP15 Barrier instructions 2014-11-20T16:34:48+00:00 Punit Agrawal punit.agrawal@arm.com 2014-11-18T11:41:26+00:00 c852f320584600a372646055d8229e063949eee7 The CP15 barrier instructions (CP15ISB, CP15DSB and CP15DMB) are deprecated in the ARMv7 architecture, superseded by ISB, DSB and DMB instructions respectively. Some implementations may provide the ability to disable the CP15 barriers by disabling the CP15BEN bit in SCTLR_EL1. If not enabled, the encodings for these instructions become undefined. To support legacy software using these instructions, this patch register hooks to - * emulate CP15 barriers and warn the user about their use * toggle CP15BEN in SCTLR_EL1 Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
The CP15 barrier instructions (CP15ISB, CP15DSB and CP15DMB) are
deprecated in the ARMv7 architecture, superseded by ISB, DSB and DMB
instructions respectively. Some implementations may provide the
ability to disable the CP15 barriers by disabling the CP15BEN bit in
SCTLR_EL1. If not enabled, the encodings for these instructions become
undefined.

To support legacy software using these instructions, this patch
register hooks to -
* emulate CP15 barriers and warn the user about their use
* toggle CP15BEN in SCTLR_EL1

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: Port SWP/SWPB emulation support from arm 2014-11-20T16:34:31+00:00 Punit Agrawal punit.agrawal@arm.com 2014-11-18T11:41:25+00:00 bd35a4adc4131c530ec7d90242555eac7b3dbe3f The SWP instruction was deprecated in the ARMv6 architecture. The ARMv7 multiprocessing extensions mandate that SWP/SWPB instructions are treated as undefined from reset, with the ability to enable them through the System Control Register SW bit. With ARMv8, the option to enable these instructions through System Control Register was dropped as well. To support legacy applications using these instructions, port the emulation of the SWP and SWPB instructions from the arm port to arm64. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> 
The SWP instruction was deprecated in the ARMv6 architecture. The
ARMv7 multiprocessing extensions mandate that SWP/SWPB instructions
are treated as undefined from reset, with the ability to enable them
through the System Control Register SW bit. With ARMv8, the option to
enable these instructions through System Control Register was dropped
as well.

To support legacy applications using these instructions, port the
emulation of the SWP and SWPB instructions from the arm port to arm64.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>