Commit Graph

9 Commits

Author SHA1 Message Date
Heinrich Schuchardt bb6dd5757c arm/mach-vexpress: array accessed out of bounds
dcscb_allcpus_mask is an array of size 2.

The index variable cluster has to be checked against this limit
before accessing the array.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
2014-04-24 11:41:12 +01:00
Nicolas Pitre c9d347e027 ARM: 8009/1: dcscb.c: remove call to outer_flush_all()
Strictly speaking this call is a no-op on the platform where dcscb.c is
used since it only has architected caches.  The call was there as a hint
to people inspired by this code when writing their own backend, but the
hint might not always be correct.

For example, if a PL310 were to be used it wouldn't be safe to call
the regular outer_flush_all() as atomic instructions for locking
are involved in that case and those instructions cannot be assumed to
still be operational after v7_exit_coherency_flush() has returned.
Given no other CPUs (in the cluster) should be running at that point
then standard concurrency concerns wouldn't apply.

So let's simply kill this call for now and enhance the existing comment.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-07 15:27:05 +01:00
Nicolas Pitre 39792c7cf3 ARM: 7861/1: cacheflush: consolidate single-CPU ARMv7 cache disabling code
This code is becoming duplicated in many places.  So let's consolidate
it into a handy macro that is known to be right and available for reuse.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-29 11:06:23 +00:00
Nicolas Pitre fac2e57742 ARM: vexpress/MCPM: fix cache disable sequence when CONFIG_FRAME_POINTER=y
If CONFIG_FRAME_POINTER=y we get the following error:

arch/arm/mach-vexpress/tc2_pm.c: In function 'tc2_pm_down':
arch/arm/mach-vexpress/tc2_pm.c:200:1: error: fp cannot be used in asm here

Let's fix that by explicitly preserving r11 on the stack and removing it
from the clobber list.

Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-14 13:05:42 -07:00
Nicolas Pitre e8f9bb1bd6 ARM: vexpress/dcscb: fix cache disabling sequences
Unlike real A15/A7's, the RTSM simulation doesn't appear to hit the
cache when the CTRL.C bit is cleared.  Let's ensure there is no memory
access within the disable and flush cache sequence, including to the
stack.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
2013-07-22 12:26:09 -04:00
Dave Martin d41418c0c0 ARM: vexpress/dcscb: handle platform coherency exit/setup and CCI
Add the required code to properly handle race free platform coherency exit
to the DCSCB power down method.

The power_up_setup callback is used to enable the CCI interface for
the cluster being brought up.  This must be done in assembly before
the kernel environment is entered.

Thanks to Achin Gupta and Nicolas Pitre for their help and
contributions.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2013-05-29 15:50:35 -04:00
Nicolas Pitre 2f2df895ee ARM: vexpress/dcscb: do not hardcode number of CPUs per cluster
If 4 CPUs are assumed, the A15x1-A7x1 model configuration would never
shut down the initial cluster as the 0xf reset bit mask will never be
observed.  Let's construct this mask based on the provided information
in the DCSCB config register for the number of CPUs per cluster.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2013-05-29 15:50:35 -04:00
Nicolas Pitre 13eae144ec ARM: vexpress/dcscb: add CPU use counts to the power up/down API implementation
It is possible for a CPU to be told to power up before it managed
to power itself down.  Solve this race with a usage count to deal
with this possibility as mandated by the MCPM API definition.

Signed-off-by: nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2013-05-29 15:50:35 -04:00
Nicolas Pitre 1e904e1bf6 ARM: vexpress: introduce DCSCB support
This adds basic CPU and cluster reset controls on RTSM for the
A15x4-A7x4 model configuration using the Dual Cluster System
Configuration Block (DCSCB).

The cache coherency interconnect (CCI) is not handled yet.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Pawel Moll <pawel.moll@arm.com>
2013-05-29 15:50:34 -04:00