Commit Graph

15 Commits

Author SHA1 Message Date
Shawn Guo c716483c3d ARM: 8122/1: smp_scu: enable SCU standby support
With SCU standby enabled, SCU CLK will be turned off when all processors
are in WFI mode.  And the clock will be turned on when any processor
leaves WFI mode.

This behavior should be preferable in terms of power efficiency of
system idle.  So let's set the SCU standby bit to enable the support in
function scu_enable().

Cortex-A9 earlier than r2p0 has no standby bit in SCU, so we need to
skip setting the bit for those.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-08-02 08:51:53 +01:00
Shawn Guo f8f3d4ed0d ARM: 8121/1: smp_scu: use macro for SCU enable bit
Use macro instead of magic number for SCU enable bit.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-08-02 08:51:52 +01:00
Ben Dooks 099a480913 ARM: smp_scu: data endian fixes
The smp_scu driver needs to use the relaxed readl/write accessors
to avoid any issues with the endian mode the processor core is in.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
2013-10-19 20:46:33 +01:00
Russell King 73a09d212e Merge branch 'for-next' of git://git.pengutronix.de/git/ukl/linux into devel-stable
Conflicts:
	arch/arm/include/asm/cputype.h

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-03-09 15:49:32 +00:00
Uwe Kleine-König ac52e83f4c ARM: use read_cpuid_id() instead of read_cpuid(CPUID_ID)
Both calls are identical currently. This patch prepares to deprecate
read_cpuid on machines without cp15.

Also move an unconditional usage of read_cpuid_cachetype to a more local
scope as read_cpuid_cachetype uses read_cpuid, too.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1359646587-1788-1-git-send-email-u.kleine-koenig@pengutronix.de
2013-01-31 21:44:47 +01:00
Rob Herring c7d5b93e98 ARM: scu: mask cluster id from cpu_logical_map
With commit a0ae0240 (ARM: kernel: add device tree init map function),
the cpu id value may include the cluster id and is no longer 0-3, so we
need to mask it in scu_power_mode to get the local cpu number. Since we
are only dealing with the cpu we are running on, the cluster id should
not ever be needed.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-01-31 13:54:16 -06:00
Will Deacon 0bd82adee3 ARM: 7347/1: SCU: use cpu_logical_map for per-CPU low power mode
scu_power_mode changes the power mode for the current CPU, which it
determines from smp_processor_id(). However, this assumes that the
physical CPU number is equal to Linux's logical CPU number and if this
is not true, we will power off the wrong CPU.

This patch uses cpu_logical_map to translate the logical CPU number
into a physical one in scu_power_mode.

Reported-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-28 17:31:37 +01:00
Russell King 06afb1a087 Merge branches 'arnd-randcfg-fixes', 'debug', 'io' (early part), 'l2x0', 'p2v', 'pgt' (early part) and 'smp' into for-linus 2011-10-25 08:19:29 +01:00
Shawn Guo 26a527e69d ARM: 7100/1: smp_scu: remove __init annotation from scu_enable()
When Cortex-A9 MPCore resumes from Dormant or Shutdown modes,
SCU needs to be re-enabled.  This patch removes __init annotation
from function scu_enable(), so that platform resume procedure can
call it to re-enable SCU.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-17 09:02:43 +01:00
Will Deacon f630c1bdfb ARM: 7091/1: errata: D-cache line maintenance operation by MVA may not succeed
This patch implements a workaround for erratum 764369 affecting
Cortex-A9 MPCore with two or more processors (all current revisions).
Under certain timing circumstances, a data cache line maintenance
operation by MVA targeting an Inner Shareable memory region may fail to
proceed up to either the Point of Coherency or to the Point of
Unification of the system. This workaround adds a DSB instruction before
the relevant cache maintenance functions and sets a specific bit in the
diagnostic control register of the SCU.

Cc: <stable@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-17 12:47:17 +01:00
Rob Herring 10cdc7e512 ARM: 6960/1: allow enabling SCU code on UP
The scu_power_mode function can be used on UP builds as it drives signals
to an SOC power controller. So make it selectable for !SMP.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-07-06 20:55:15 +01:00
Russell King 292ec42af7 ARM: pm: add function to set WFI low-power mode for SMP CPUs
Add a function to set the SCU low-power mode for SMP CPUs.  This
centralizes this functionality rather than having to expose the
SCU register definitions to each platform.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-11 12:29:18 +00:00
Catalin Marinas 9b229fa095 Check whether the SCU was already initialised
If Linux is running in non-secure mode, this register may have been
already initialised and writing to the control register not allowed.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-11-05 10:10:36 +00:00
Catalin Marinas af73110d23 [ARM] 5516/1: Flush the D-cache after initialising the SCU
On MP systems, the data loaded by CPU0 before the SCU was initialised
may not be visible to the other CPUs.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This also includes the following compile fix:

This patch includes 'asm/cacheflush.h' which is needed to use
'flush_cache_all()' function.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-28 13:52:05 +01:00
Russell King a8cbcd92bd [ARM] smp: separate SCU support code from realview
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-05-17 19:00:37 +01:00