Commit Graph

16 Commits

Author SHA1 Message Date
Geert Uytterhoeven 791581e36d dt-bindings: arm: idle-states: Move exit-latency-us explanation
Move exit-latency-us explanation to exit-latency-us section.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-09-02 15:58:27 +01:00
Geert Uytterhoeven 19155f56a1 dt-bindings: arm: idle-states: Add punctuation to improve readability
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-09-02 15:58:15 +01:00
Geert Uytterhoeven 0801400709 dt-bindings: arm: idle-states: Correct "constraint guarantees"
Correct "constraints guarantees" to "constraint guarantees".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-09-02 15:58:06 +01:00
Geert Uytterhoeven 06c3145dee dt-bindings: arm: idle-states: Correct references to wake-up delay
The paragraph explains the use of wakup-delay, as defined above.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-09-02 15:57:54 +01:00
Geert Uytterhoeven fb2d23291b dt-bindings: arm: idle-states: Use "e.g." and "i.e." consistently
Replace abbreviations "eg" and "ie" by "e.g." resp. "i.e." for
consistency.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-09-02 15:56:46 +01:00
Mauro Carvalho Chehab bff9e34c67 docs: fix broken doc references due to renames
Some files got renamed but probably due to some merge conflicts,
a few references still point to the old locations.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-17 06:57:51 -03:00
Rob Herring 5025ef8b7a dt-bindings: arm: Convert PSCI binding to json-schema
Convert the PSCI binding to use DT schema format.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-06-27 11:32:51 -06:00
Amit Kucheria 4c0a59e112 Documentation: arm: Link idle-states binding to "enable-method" property
The "enable-method" property for cpu nodes needs to be "psci" for CPU
idle management to be setup correctly.

Add a note to the binding documentation to this effect to make it
obvious.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-06-13 17:13:32 -06:00
Otto Sabart 8217724eb7 doc: bindings: fix bad reference to ARM CPU bindings
The primecell.txt and cpus.txt files were converted into YAML. This
patch updates old references with new ones.

Fixes: d3c207eeb9 ("dt-bindings: arm: Convert primecell binding to json-schema")
Fixes: 672951cbd1 ("dt-bindings: arm: Convert cpu binding to json-schema")
Signed-off-by: Otto Sabart <ottosabart@seberm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2019-01-11 17:12:50 -06:00
Will Deacon 806654a966 Documentation: Use "while" instead of "whilst"
Whilst making an unrelated change to some Documentation, Linus sayeth:

  | Afaik, even in Britain, "whilst" is unusual and considered more
  | formal, and "while" is the common word.
  |
  | [...]
  |
  | Can we just admit that we work with computers, and we don't need to
  | use þe eald Englisc spelling of words that most of the world never
  | uses?

dictionary.com refers to the word as "Chiefly British", which is
probably an undesirable attribute for technical documentation.

Replace all occurrences under Documentation/ with "while".

Cc: David Howells <dhowells@redhat.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20 09:30:43 -07:00
Amit Kucheria e9880240e4 arm64: dts: Fix various entry-method properties to reflect documentation
The idle-states binding documentation[1] mentions that the
'entry-method' property is required on 64-bit platforms and must be
set to "psci".

commit a13f18f59d ("Documentation: arm: Fix typo in the idle-states
bindings examples") attempted to fix this earlier but clearly more is
needed.

Fix the cpu-capacity.txt documentation that uses the incorrect value so
we don't get copy-paste errors like these. Clarify the language in
idle-states.txt by removing the reference to the psci bindings that
might be causing this confusion.

Finally, fix devicetrees of various boards to reflect current
documentation.

[1] Documentation/devicetree/bindings/arm/idle-states.txt (see
idle-states node)

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Li Yang <leoyang.li@nxp.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2018-08-24 08:50:02 -07:00
Frank Rowand 076fb0c4b6 of: update ePAPR references to point to Devicetree Specification
The Devicetree Specification has superseded the ePAPR as the
base specification for bindings.  Update files in Documentation
to reference the new document.

First reference to ePAPR in Documentation/devicetree/bindings/arm/cci.txt
is generic, remove it.

Some files are not updated because there is no hypervisor chapter
in the Devicetree Specification:
   Documentation/devicetree/bindings/powerpc/fsl/msi-pic.txt
   Documenation/virtual/kvm/api.txt
   Documenation/virtual/kvm/ppc-pv.txt

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2017-06-22 11:22:06 -05:00
Lorenzo Pieralisi a13f18f59d Documentation: arm: Fix typo in the idle-states bindings examples
The idle-states bindings mandate that the entry-method string
in the idle-states node must be "psci" for ARM v8 64-bit systems,
but the examples in the bindings report a wrong entry-method string.
Owing to this typo, some dts in the kernel wrongly defined the
entry-method property, since they likely cut and pasted the example
definition without paying attention to the bindings definitions.

This patch fixes the typo in the DT idle states bindings examples and
respective dts in the kernel so that the bindings and related dts
files are made compliant.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Howard Chen <howard.chen@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Rob Herring <robh@kernel.org>
2015-09-24 17:55:32 -05:00
Lorenzo Pieralisi c00bc5df7c drivers: cpuidle: Add idle-state-name description to ARM idle states
On ARM machines, where generally speaking the idle state numbering has
no fixed and standard meaning it is useful to provide a description
of the idle state inner workings for benchmarking and monitoring purposes.

This patch adds a property to the idle states bindings that if present
gives platform firmware a means of describing the idle state and export
the string description to user space.

The patch updates the DT parsing code accordingly to take the description,
if present, into consideration.

Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-11-19 10:16:23 +01:00
Lorenzo Pieralisi 97735da074 drivers: cpuidle: Add status property to ARM idle states
On some platforms the device tree bindings must provide the kernel
with a status flag for idle states, that defines whether the idle
state is operational or not in the current configuration.

This patch adds a status property to the ARM idle states compliant
with ePAPR v1.1 and updates the DT parsing code accordingly.

Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-11-19 10:16:15 +01:00
Lorenzo Pieralisi 3f8161b260 Documentation: arm: define DT idle states bindings
ARM based platforms implement a variety of power management schemes that
allow processors to enter idle states at run-time.
The parameters defining these idle states vary on a per-platform basis forcing
the OS to hardcode the state parameters in platform specific static tables
whose size grows as the number of platforms supported in the kernel increases
and hampers device drivers standardization.

Therefore, this patch aims at standardizing idle state device tree bindings
for ARM platforms. Bindings define idle state parameters inclusive of entry
methods and state latencies, to allow operating systems to retrieve the
configuration entries from the device tree and initialize the related power
management drivers, paving the way for common code in the kernel to deal with
idle states and removing the need for static data in current and previous
kernel versions.

ARM64 platforms require the DT to define an entry-method property
for idle states.

On system implementing PSCI as an enable-method to enter low-power
states the PSCI CPU suspend method requires the power_state parameter to
be passed to the PSCI CPU suspend function.

This parameter is specific to a power state and platform specific,
therefore must be provided by firmware to the OS in order to enable
proper call sequence.

Thus, this patch also adds a property in the PSCI bindings that
describes how the PSCI CPU suspend power_state parameter should be
defined in DT in all device nodes that rely on PSCI CPU suspend method usage.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Sebastian Capella <sebcape@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-09-12 10:48:55 +01:00