u-boot.git/include/power-domain.h, branch master

power-domain: Add support for refcounting (again)

2025-04-28T13:41:19+00:00

It is very surprising that such an uclass, specifically designed to
handle resources that may be shared by different devices, is not keeping
the count of the number of times a power domain has been
enabled/disabled to avoid shutting it down unexpectedly or disabling it
several times.

Doing this causes troubles on eg. i.MX8MP because disabling power
domains can be done in recursive loops were the same power domain
disabled up to 4 times in a row. PGCs seem to have tight FSM internal
timings to respect and it is easy to produce a race condition that puts
the power domains in an unstable state, leading to ADB400 errors and
later crashes in Linux.

Some drivers implement their own mechanism for that, but it is probably
best to add this feature in the uclass and share the common code across
drivers. In order to avoid breaking existing drivers, refcounting is
only enabled if the number of subdomains a device node supports is
explicitly set in the probe function. ->xlate() callbacks will return
the power domain ID which is then being used as the array index to reach
the correct refcounter.

As we do not want to break existing users while stile getting
interesting error codes, the implementation is split between:
- a low-level helper reporting error codes if the requested transition
  could not be operated,
- a higher-level helper ignoring the "non error" codes, like EALREADY and
  EBUSY.

CI tests using power domains are slightly updated to make sure the count
of on/off calls is even and the results match what we *now* expect. They
are also extended to test the low-level functions.

Signed-off-by: Miquel Raynal

Revert "power-domain: Add refcounting"

2025-04-18T15:35:39+00:00

Unfortunately this change breaks boot on K3 platform.
U-Boot will hang after:

  U-Boot SPL 2025.04-01050-ga40fc5afaec0 (Apr 14 2025 - 07:31:32 +0000)
  SYSFW ABI: 3.1 (firmware rev 0x0009 '9.2.7--v09.02.07 (Kool Koala)')

This reverts commit 197376fbf300e92afa0a1583815d9c9eb52d613a as
suggested in [1].

[1] https://lists.denx.de/pipermail/u-boot/2025-April/587032.html

Signed-off-by: Wadim Egorov 
Acked-by: Miquel Raynal

power-domain: Add refcounting

2025-04-11T01:32:55+00:00

It is very surprising that such an uclass, specifically designed to
handle resources that may be shared by different devices, is not keeping
the count of the number of times a power domain has been
enabled/disabled to avoid shutting it down unexpectedly or disabling it
several times.

Doing this causes troubles on eg. i.MX8MP because disabling power
domains can be done in recursive loops were the same power domain
disabled up to 4 times in a row. PGCs seem to have tight FSM internal
timings to respect and it is easy to produce a race condition that puts
the power domains in an unstable state, leading to ADB400 errors and
later crashes in Linux.

CI tests using power domains are slightly updated to make sure the count
of on/off calls is even and the results match what we *now* expect.

As we do not want to break existing users while stile getting
interesting error codes, the implementation is split between:
- a low-level helper reporting error codes if the requested transition
  could not be operated,
- a higher-level helper ignoring the "non error" codes, like EALREADY and
  EBUSY.

Signed-off-by: Miquel Raynal

headers: don't depend on errno.h being available

2024-01-24T16:12:11+00:00

These headers follow the pattern:

| #if CONFIG_IS_ENABLED(FANCY_FEATURE)
|   void foo(void);
| #else
|   static inline void foo(void) { return -ENOSYS; }
| #endif

In the #else path ENOSYS is used, however linux/errno.h is not included.
If errno.h has not been included already the compiler errors out even
if the inline function is not referenced.

Make those headers self contained.

Signed-off-by: Max Krummenacher 
Reviewed-by: Francesco Dolcini 
Reviewed-by: Tom Rini

power_domain: Add power_domain_get_by_name()

2022-04-21T10:44:23+00:00

Implement power_domain_get_by_name() convenience function which parses
DT property 'power-domain-names' and looks up power domain by matching
name.

Signed-off-by: Marek Vasut 
Cc: Patrick Delaunay 
Cc: Simon Glass

doc: replace @return by Return:

2022-01-19T17:11:34+00:00

Sphinx expects Return: and not @return to indicate a return value.

find . -name '*.c' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

find . -name '*.h' -exec \
sed -i 's/^\(\s\)\*\(\s*\)@return\(\s\)/\1*\2Return:\3/' {} \;

Signed-off-by: Heinrich Schuchardt

treewide: Simply conditions with the new OF_REAL

2021-09-25T15:46:15+00:00

Use this new Kconfig to simplify the compilation conditions where
appropriate.

Signed-off-by: Simon Glass

power: domain: Introduce dev_power_domain_off

2019-10-15T14:40:03+00:00

Add dev_power_domain_off() api to disable all the power-domains
corresponding to a device

Signed-off-by: Lokesh Vutla 
Reviewed-by: Simon Glass

power: domain: add dev_power_domain_on

2019-10-15T14:40:02+00:00

Add this new API to power on multiple domains attached
to a device.

Signed-off-by: Peng Fan 
Reviewed-by: Lokesh Vutla 
Changed to static inline and added a condition into C file:
Signed-off-by: Simon Glass

power-domain: Add private data to power domain

2019-07-27T01:49:22+00:00

Certain drivers want to attach private data corresponding to each
power domain. This data might be specific be to the drvier. So add
a priv entry into the power_domain structure.

Signed-off-by: Lokesh Vutla