firmware: arm_scpi: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/e7b4bc389949c3613a358bd8e57d70d7acd5552b.1703693980.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: arm_scpi: Use device_get_match_data()

Use preferred device_get_match_data() instead of of_match_device() to
get the driver match data. With this, adjust the includes to explicitly
include the correct headers.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20231006224650.445424-1-robh@kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Ensure scpi_info is not assigned if the probe fails

When scpi probe fails, at any point, we need to ensure that the scpi_info
is not set and will remain NULL until the probe succeeds. If it is not
taken care, then it could result use-after-free as the value is exported
via get_scpi_ops() and could refer to a memory allocated via devm_kzalloc()
but freed when the probe fails.

Link: https://lore.kernel.org/r/20220701160310.148344-1-sudeep.holla@arm.com
Cc: stable@vger.kernel.org # 4.19+
Reported-by: huhai <huhai@kylinos.cn>
Reviewed-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Add compatibility checks for shmem node

The shared memory node used for communication between the firmware and
the OS should be compatible with one of the following:
- amlogic,meson-gxbb-scp-shmem
- amlogic,meson-axg-scp-shmem
- arm,juno-scp-shmem
- arm,scp-shmem
Add the check for the same while parsing the node before fetching the memory
regions.

Link: https://lore.kernel.org/r/20210602073851.1005607-1-sudeep.holla@arm.com
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Prevent the ternary sign expansion bug

How the type promotion works in ternary expressions is a bit tricky.
The problem is that scpi_clk_get_val() returns longs, "ret" is a int
which holds a negative error code, and le32_to_cpu() is an unsigned int.
We want the negative error code to be cast to a negative long. But
because le32_to_cpu() is an u32 then "ret" is type promoted to u32 and
becomes a high positive and then it is promoted to long and it is still
a high positive value.

Fix this by getting rid of the ternary.

Link: https://lore.kernel.org/r/YIE7pdqV/h10tEAK@mwanda
Fixes: 8cb7cf56c9fe ("firmware: add support for ARM System Control and Power Interface(SCPI) protocol")
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[sudeep.holla: changed to return 0 as clock rate on error]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertenly introduced[3] to the codebase from now on.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Replace the zero-length member "payload" in {legacy_,}scpi_shared_mem
structures with flexible-array.

Link: https://lore.kernel.org/r/20200211231604.GA17274@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: convert platform driver to use dev_groups

Platform drivers now have the option to have the platform core create
and remove any needed sysfs attribute files. So take advantage of that
and do not register "by hand" a sysfs group of attributes.

Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190731124349.4474-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms and conditions of the gnu general public license
version 2 as published by the free software foundation this program
is distributed in the hope it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 228 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.107155473@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: devm_kzalloc() -> devm_kcalloc()

The devm_kzalloc() function has a 2-factor argument form, devm_kcalloc().
This patch replaces cases of:

devm_kzalloc(handle, a * b, gfp)

with:
devm_kcalloc(handle, a * b, gfp)

as well as handling cases of:

devm_kzalloc(handle, a * b * c, gfp)

with:

devm_kzalloc(handle, array3_size(a, b, c), gfp)

as it's slightly less ugly than:

devm_kcalloc(handle, array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

devm_kzalloc(handle, 4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

Some manual whitespace fixes were needed in this patch, as Coccinelle
really liked to write "=devm_kcalloc..." instead of "= devm_kcalloc...".

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
expression HANDLE;
type TYPE;
expression THING, E;
@@

(
devm_kzalloc(HANDLE,
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
devm_kzalloc(HANDLE,
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression HANDLE;
expression COUNT;
typedef u8;
typedef __u8;
@@

(
devm_kzalloc(HANDLE,
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(char) * COUNT
+ COUNT
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
expression HANDLE;
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_ID)
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_ID
+ COUNT_ID, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (COUNT_CONST)
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * COUNT_CONST
+ COUNT_CONST, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_ID)
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_ID
+ COUNT_ID, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (COUNT_CONST)
+ COUNT_CONST, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * COUNT_CONST
+ COUNT_CONST, sizeof(THING)
, ...)
)

// 2-factor product, only identifiers.
@@
expression HANDLE;
identifier SIZE, COUNT;
@@

- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- SIZE * COUNT
+ COUNT, SIZE
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression HANDLE;
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression HANDLE;
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
devm_kzalloc(HANDLE,
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
expression HANDLE;
identifier STRIDE, SIZE, COUNT;
@@

(
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
devm_kzalloc(HANDLE,
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression HANDLE;
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE,
- (E1) * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * E3
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- (E1) * (E2) * (E3)
+ array3_size(E1, E2, E3)
, ...)
|
devm_kzalloc(HANDLE,
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression HANDLE;
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
devm_kzalloc(HANDLE, sizeof(THING) * C2, ...)
|
devm_kzalloc(HANDLE, sizeof(TYPE) * C2, ...)
|
devm_kzalloc(HANDLE, C1 * C2 * C3, ...)
|
devm_kzalloc(HANDLE, C1 * C2, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * (E2)
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(TYPE) * E2
+ E2, sizeof(TYPE)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * (E2)
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- sizeof(THING) * E2
+ E2, sizeof(THING)
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * E2
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- (E1) * (E2)
+ E1, E2
, ...)
|
- devm_kzalloc
+ devm_kcalloc
(HANDLE,
- E1 * E2
+ E1, E2
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

firmware: arm_scpi: improve info message for pre-1.0 firmware

On legacy pre-1.0 firmware versions so far the following message is
printed which may cause some confusion:
SCP Protocol 0.0 Firmware 0.0.0 version

Therefore replace the message with the following if firmware doesn't
provide usable version information:
SCP Protocol legacy pre-1.0 firmware

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: use FIELD_GET/_PREP to simplify macro definitions

Macro definitions can be simplified by making use of the FIELD_GET/_PREP
bitfield macros.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove struct sensor_capabilities

One more single-element struct was left, remove it.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: fix incorrect __iomem accesses using correct accessors

At several positions in the code sparse complains about incorrect access
to __iomem annotated memory. Fix this and make sparse happy.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
[Sudeep Holla: changed the patch title to describe the change]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove all single element structures

Both clk_get_value and sensor_value structures contains a single element
and hence needs no packing making the whole structure defination
unnecessary.

This patch gets rid of both those unnecessary structures.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: drop unnecessary type cast to scpi_shared_mem

This patch drops the only present type cast of the SCPI payload pointer
to scpi_shared_mem inorder to align with other occurrences, IOW for
consistency.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve struct sensor_value

lo_val and hi_val together in this order are a little endian 64 bit value.
Therefore we can simplify struct sensor_value and the code by defining
it as a __le64 value and by using le64_to_cpu.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve handling of protocol and firmware version subfields

By using FIELD_GET and proper masks we can avoid quite some shifting
and masking macro magic and make the code better readable.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve struct dvfs_info to make code better readable

Making the header subfields members of struct dvfs_info allows to make
the code better readable and avoids some macro magic.

In addition remove a useless statement using info->latency.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: make scpi_probe completely device-managed

Replace two remaining functions in probe with their devm versions.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: make freeing mbox channels device-managed

Make freeing the mbox channels device-managed, thus further simplifying
scpi_remove and and one further step to get rid of scpi_remove.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove two unneeded devm_kfree's in scpi_remove

Both memory areas are free'd anyway when the device is destroyed,
so we don't have to do it manually.

Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Revert updates made during v4.15 merge window

Revert "Merge tag 'scpi-updates-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into next/drivers"

Paraphrased from email from Kevin Hilman:

Revert ARM SCPI changes since v4.14.

Untested changes caused regressions in SCPI and CPUfreq/DVFS failures
on most Amlogic SoCs. Changes reverted for v4.15 so they can be better
reviewed and tested.

These ARM SCPI changes caused SCPI regressions resulting in CPUfreq
failures on most Amlogic SoCs (found by kernelci.org.)

Unfortunately, this was not caught in linux-next due to other bugs/panics
on these platforms masking this problem so we've only found it since
we've fixed the other issues.

Since we're already in the -rc cycle, I'd prefer to revert to a known
working state (that of v4.14) rather than finding/reverting a subset,
which would just lead to another untested state.

These changes can then have some time to be better reviewed and tested
and resubmitted for v4.16.

Kevin Hilman has tested this revert on the affected Amlogic SoCs and
verified that we're back to the previous (working) condition.

This reverts commit 6710acf2596a29f7351e8165d981645f403e0025, reversing
changes made to 4b367f2e8854da34d14bd154ff4432fb49f69b36.

Reported-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

firmware: arm_scpi: silence sparse warnings

At several positions in the code sparse complains about incorrect access
to __iomem annotated memory. Fix this and make sparse happy.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove all single element structures

Both clk_get_value and sensor_value structures contains a single element
and hence needs no packing making the whole structure defination
unnecessary.

This patch gets rid of both those unnecessary structures.

Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: drop unnecessary type cast to scpi_shared_mem

This patch drops the only present type cast of the SCPI payload pointer
to scpi_shared_mem inorder to align with other occurrences, IOW for
consistency.

Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve struct sensor_value

lo_val and hi_val together in this order are a little endian 64 bit value.
Therefore we can simplify struct sensor_value and the code by defining
it as a __le64 value and by using le64_to_cpu.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve handling of protocol and firmware version subfields

By using FIELD_GET and proper masks we can avoid quite some shifting
and masking macro magic and make the code better readable.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: improve struct dvfs_info to make code better readable

Making the header subfields members of struct dvfs_info allows to make
the code better readable and avoids some macro magic.

In addition remove a useless statement using info->latency.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove scpi_remove

sysfs_create_groups and of_platform_populate can be replaced with the
device-managed versions what allows us to remove scpi_remove.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: make freeing mbox channels device-managed

Make freeing the mbox channels device-managed, thus further simplifying
scpi_remove and and one further step to get rid of scpi_remove.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: pre-populate dvfs info in scpi_probe

Pre-populating the dvfs info data in scpi_probe allows to make all
memory allocations device-managed. This helps to simplify scpi_remove
and eventually to get rid of scpi_remove completely.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
[sudeep.holla: changed to continue probe even if scpi_dvfs_populate_info fails]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove two unneeded devm_kfree's in scpi_remove

Both memory areas are free'd anyway when the device is destroyed,
so we don't have to do it manually.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove usage of drvdata and don't reset scpi_info to null

There's no benefit using drvdata as variable scpi_info is global.

Setting scpi_info to NULL in scpi_remove isn't needed too. If arm_scpi
is built-in, then this code is never used. And if arm_scpi is built as
a module and some other module calls get_scpi_ops() then due to this
dependency scpi_remove is called only after the other module has been
removed.

Last but not least, users usually store the result of get_scpi_ops(),
therefore setting scpi_info to NULL wouldn't really help.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
[sudeep.holla: reworded the commit log a bit]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: fix endianness of dev_id in struct dev_pstate_set

scpi_device_{g,s}et_power_state correctly handles the conversion of
endianness for dev_id using cpu_to_le16. However dev_id is declared
as u16 in struct dev_pstate_set which is incorrect.

This patch fixes the endianness of dev_id in dev_pstate_set structure.

Fixes: 37a441dcd5f4 ("firmware: arm_scpi: add support for device power state management")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

firmware: arm_scpi: add support to populate OPPs and get transition latency

Currently only CPU devices use the transition latency and the OPPs
populated in the SCPI driver. scpi-cpufreq has logic to handle these.
However, even GPU and other users of SCPI DVFS will need the same logic.

In order to avoid duplication, this patch adds support to get DVFS
transition latency and add all the OPPs to the device using OPP library
helper functions. The helper functions added here can be used for any
device whose DVFS are managed by SCPI.

Also, we also have incorrect dependency on the cluster identifier for
the CPUs. It's fundamentally wrong as the domain id need not match the
cluster id. This patch gets rid of that dependency by making use of the
clock bindings which are already in place.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: reinit completion instead of full init_completion()

Instead of performing full initialization of the completion structure
on each transfer in scpi_send_message(), we initialize it at boot time
(more specifically, in the relevant probe() function) and use
reinit_completion() to reset ->done counter on each message transfer.

Signed-off-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: fix reading sensor values on pre-1.0 SCPI firmwares

The pre-1.0 SCPI firmwares are using single __le32 as sensor value,
while the SCPI v1.0 protocol uses two __le32 as sensor values(64bit)
split into 32bit upper and 32bit lower value.

Using an "struct sensor_value" to read the sensor value on a pre-1.0
SCPI firmware gives garbage in the "hi_val" field.

This patch fixes the issue by reading only the lower 32-bit value for
all pre-1.0 SCPI versions.

Suggested-by: Sudeep Holla <Sudeep.Holla@arm.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
[sudeep.holla@arm.com: updated the commit log to reflect the implementation]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add support for pre-v1.0 SCPI compatible

This patch adds new DT match table to setup the support for SCPI protocol
versions prior to v1.0 releases. It also adds "arm,scpi-pre-1.0" to the
SCPI match entry.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: allow firmware with get_capabilities not implemented

On Amlogic SCPI legacy implementation, the GET_CAPABILITIES command is
not supported, failover by using 0.0.0 version.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[sudeep.holla@arm.com: changed the subject]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add alternative legacy structures, functions and macros

This patch adds support for the Legacy SCPI protocol that is available
in very early JUNO versions and shipped Amlogic ARMv8 based SoCs. Some
Rockchip SoC are also known to use this version of protocol with
extended vendor commands.

In order to support the legacy SCPI protocol variant, we need to add the
structures and macros definitions that varies against the final SCPI v1.0
specification.

We add the indirection table for legacy commands set so that it can
co-exist with the standard v1.0 command set. It also adds bitmap field
for channel selection since the legacy protocol mandates to send only
selected subset of the commands on the high priority channel.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[sudeep.holla@arm.com: Updated the changelog]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: increase MAX_DVFS_OPPS to 16 entries

Since Amlogic SoCs supports more than 8 OPPs per domains, we need increase
the OPP structure size.

This patch increases the MAX_DVFS_OPPS to 16.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add command indirection to support legacy commands

Since the legacy SCPI and the SCPI v1.0 differ in the command values,
it's better to create some sort of command indirection in the driver
to avoid repeated version check at multiple places.

This patch adds the indirection command table to allow different values
of the command across SCPI versions.

[narmstrong@baylibre.com: added cmd check in scpi_send_message]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add missing of_node_put after calling of_parse_phandle

of_node_put needs to be called when the device node which is got
from of_parse_phandle has finished using it.

Besides, of_address_to_resource always returns -EINVAL for error, delete
the assignment for ret.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add support for device power state management

SCPI protocol supports device power state management. This deals with
power states of various peripheral devices in the system other than the
core compute subsystem.

This patch adds support for the power state management of those
peripheral devices.

Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Jon Medhurst <tixy@linaro.org>
Reviewed-by: Jon Medhurst <tixy@linaro.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: mark scpi_get_sensor_value as static

scpi_get_sensor_value like other scpi operations needs to be static.
This patch marks it as static to be consistent with others.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: remove dvfs_get packed structure

dvfs_get packed structure is used to read the DVFS/OPP index from the
firmware. It just contains a single byte that needs no packing making
the whole structure defination unnecessary.

This patch replaces the unnecessary dvfs_get packed structure with an
unsigned byte.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: add support for 64-bit sensor values

SCPI specification version 1.1 extended the sensor from 32-bit to 64-bit
values in order to accommodate new sensor class with 64-bit requirements

Since the SCPI driver sets the higher 32-bit for older protocol version
to zeros, there's no need to explicitly check the SCPI protocol version
and the backward compatibility is maintainted.

Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: decrease Tx timeout to 20ms

Currently we have Tx timeout of 50ms while Rx timeout of 20 ms. Tx state
machine is maintained by the mailbox framework and Rx by SCPI driver.

It is possible that before msg_submit call tx_prepare(because of other
message in the queue and the channel being active), wait for completion
in scpi_send_message times out and the buffers are freed. In that case
when Tx state machine timer goes off later, poll_txdone calls
scpi_tx_prepare on that message, which adds it to the rx_pending list,
corrupting link pointers.

This patch reduces the Tx timeout to 20ms and increases Rx timeout to
30ms to avoid the above mentioned issue.

Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: fix send_message and sensor_get_value for big-endian

scpi_process_cmd converts the status word from little endian to cpu
endianness. However scpi_send_message again does the conversion which is
wrong and shows up as a bug only when running in big-endian kernel.

Similarly scpi_sensor_get_value passes the sensor index in the cpu
endianness to SCP which results in SCPI_ERR_RANGE in big-endian mode.

This patch fixes the above mentioned issue for big-endian kernel.

Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: arm_scpi: Extend to support sensors

ARM System Control Processor (SCP) provides an API to query and use
the sensors available in the system. Extend the SCPI driver to support
sensor messages.

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>

firmware: add support for ARM System Control and Power Interface(SCPI) protocol

This patch adds support for System Control and Power Interface (SCPI)
Message Protocol used between the Application Cores(AP) and the System
Control Processor(SCP). The MHU peripheral provides a mechanism for
inter-processor communication between SCP's M3 processor and AP.

SCP offers control and management of the core/cluster power states,
various power domain DVFS including the core/cluster, certain system
clocks configuration, thermal sensors and many others.

This protocol driver provides interface for all the client drivers using
SCPI to make use of the features offered by the SCP.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Cc: Jassi Brar <jassisinghbrar@gmail.com>
Cc: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>