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/rk3399_ARM-atf/lib/locks/exclusive/aarch64/
H A Dspinlock.Sc97cba4ea44910df1f7b1af5dba79013fb44c383 Wed Sep 25 13:03:41 UTC 2019 Soby Mathew <soby.mathew@arm.com> Fix the CAS spinlock implementation

Make the spinlock implementation use ARMv8.1-LSE CAS instruction based
on a platform build option. The CAS-based implementation used to be
unconditionally selected for all ARM8.1+ platforms.

The previous CAS spinlock implementation had a bug wherein the spin_unlock()
implementation had an `sev` after `stlr` which is not sufficient. A dsb is
needed to ensure that the stlr completes prior to the sev. Having a dsb is
heavyweight and a better solution would be to use load exclusive semantics
to monitor the lock and wake up from wfe when a store happens to the lock.
The patch implements the same.

Change-Id: I5283ce4a889376e4cc01d1b9d09afa8229a2e522
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
/rk3399_ARM-atf/docs/design/
H A Dfirmware-design.rstc97cba4ea44910df1f7b1af5dba79013fb44c383 Wed Sep 25 13:03:41 UTC 2019 Soby Mathew <soby.mathew@arm.com> Fix the CAS spinlock implementation

Make the spinlock implementation use ARMv8.1-LSE CAS instruction based
on a platform build option. The CAS-based implementation used to be
unconditionally selected for all ARM8.1+ platforms.

The previous CAS spinlock implementation had a bug wherein the spin_unlock()
implementation had an `sev` after `stlr` which is not sufficient. A dsb is
needed to ensure that the stlr completes prior to the sev. Having a dsb is
heavyweight and a better solution would be to use load exclusive semantics
to monitor the lock and wake up from wfe when a store happens to the lock.
The patch implements the same.

Change-Id: I5283ce4a889376e4cc01d1b9d09afa8229a2e522
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
/rk3399_ARM-atf/make_helpers/
H A Ddefaults.mkc97cba4ea44910df1f7b1af5dba79013fb44c383 Wed Sep 25 13:03:41 UTC 2019 Soby Mathew <soby.mathew@arm.com> Fix the CAS spinlock implementation

Make the spinlock implementation use ARMv8.1-LSE CAS instruction based
on a platform build option. The CAS-based implementation used to be
unconditionally selected for all ARM8.1+ platforms.

The previous CAS spinlock implementation had a bug wherein the spin_unlock()
implementation had an `sev` after `stlr` which is not sufficient. A dsb is
needed to ensure that the stlr completes prior to the sev. Having a dsb is
heavyweight and a better solution would be to use load exclusive semantics
to monitor the lock and wake up from wfe when a store happens to the lock.
The patch implements the same.

Change-Id: I5283ce4a889376e4cc01d1b9d09afa8229a2e522
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
/rk3399_ARM-atf/
H A DMakefilec97cba4ea44910df1f7b1af5dba79013fb44c383 Wed Sep 25 13:03:41 UTC 2019 Soby Mathew <soby.mathew@arm.com> Fix the CAS spinlock implementation

Make the spinlock implementation use ARMv8.1-LSE CAS instruction based
on a platform build option. The CAS-based implementation used to be
unconditionally selected for all ARM8.1+ platforms.

The previous CAS spinlock implementation had a bug wherein the spin_unlock()
implementation had an `sev` after `stlr` which is not sufficient. A dsb is
needed to ensure that the stlr completes prior to the sev. Having a dsb is
heavyweight and a better solution would be to use load exclusive semantics
to monitor the lock and wake up from wfe when a store happens to the lock.
The patch implements the same.

Change-Id: I5283ce4a889376e4cc01d1b9d09afa8229a2e522
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>