Commit Graph

28 Commits

Author SHA1 Message Date
Suzuki K. Poulose
e14cfad3fe arm-cci: Add aliases for PMU events
Each CCI model have different event/source codes and formats. This
patch exports this information via the sysfs, which includes the
aliases for the events. The aliases are listed by 'perf list', helping
the users to specify the name of the event instead of the binary
config values.

Each event alias must accompany the 'source' code except for the
following cases :

1) CCI-400 - cycles event, doesn't relate to an interface.
2) CCI-500 - Global events to the CCI. (Fixed source code = 0xf)

Each CCI model provides two sets of attributes(format and event),
which are dynamically populated before registering the PMU, to
allow for the appropriate information.

Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:52 +02:00
Suzuki K. Poulose
a95791efa7 arm-cci: Add CCI-500 PMU support
CCI-500 provides 8 event counters which can count any of the
supported events independently. The PMU event id is a 9-bit
value made of two parts.
	bits [8:5] - Source port
			0x0-0x6 Slave Ports
			0x8-0xD Master Ports
			0xf     Global Events to CCI
			0x7,0xe Reserved
	bits [0:4] - Event code (specific to each type of port)

The generic CCI-500 controlling interface remains the same with CCI-400.
However there are some differences in the PMU event counters.
 - No cycle counter
 - Upto 8 counters(4 in CCI-400)
 - Each counter area is 64K(4K in CCI400)
 - The counter0 starts at offset 0x10000 from the base of CCI

Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: devicetree@vger.kernel.org
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:51 +02:00
Suzuki K. Poulose
f4d58938ad arm-cci: Sanitise CCI400 PMU driver specific code
Rename CCI400 specific defintions from CCI_xxx to CCI400_xxx.

Introduce generic ARM_CCI_PMU to cover common code for handling
the CCI PMU.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:51 +02:00
Suzuki K. Poulose
312162900c arm-cci: Abstract handling for CCI events
Given that each CCI has different set of interfaces and
its associated events, it is good to abstract the validation of the
event codes to make it easier to add support for a new CCI model.

This patch also abstracts the mapping of a given event to a counter,
as there are some special counters for certain specific events.

We assume that the fixed hardware counters are always at the beginning,
so that we can use cci_model->fixed_hw_events as an upper bound to given
idx to check if we need to program the counter for an event.

Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:50 +02:00
Suzuki K. Poulose
ab5b316d4b arm-cci: Abstract out the PMU counter details
Adds the PMU model specific counters to the PMU model
abstraction to make it easier to add a new PMU.

The patch cleans up the naming convention used all over
the code.
e.g, CCI_PMU_MAX_HW_EVENTS => maximum number of events that
can be counted at any time, which is in fact the maximum
number of counters available.

Change all such namings to use 'counters' instead of events.

This patch also abstracts the following:

1) Size of a PMU event counter area.
2) Maximum number of programmable counters supported by the PMU model
3) Number of counters which counts fixed events (e.g, cycle
  counter on CCI-400).

Also changes some of the static allocation of the data
structures to dynamic, to accommodate the number of events
supported by a PMU.

Gets rid ofthe CCI_PMU_* defines for the model. All such
data should be accessed via the model abstraction.

Limits the number of counters to the maximum supported
by the 'model'.

Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:49 +02:00
Suzuki K. Poulose
a1a076d767 arm-cci: Cleanup PMU driver code
This patch gets rid of the global struct cci_pmu variable and makes
the code use the cci_pmu explicitly. Makes code a bit more robust
and reader friendly.

Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-29 16:43:49 +02:00
Mark Salter
454be2af5b drivers: CCI: fix used_mask init in validate_group()
Currently in validate_group(), there is a static initializer
for fake_pmu.used_mask which is based on CPU_BITS_NONE but
the used_mask array size is based on CCI_PMU_MAX_HW_EVENTS.
CCI_PMU_MAX_HW_EVENTS is not based on NR_CPUS, so CPU_BITS_NONE
is not correct and will cause a build failure if NR_CPUS
is set high enough to make CPU_BITS_NONE larger than used_mask.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2015-05-07 18:29:18 +02:00
Suzuki K. Poulose
874c571414 arm-cci: Fix CCI PMU event validation
We mask the event with the CCI_PMU_EVENT_MASK, before passing
the config to pmu_validate_hw_event(), which causes extra bits
to be ignored and qualifies an invalid event code as valid.

e.g,
 $ perf stat -a -C 0 -e CCI_400/config=0x1ff,name=cycles/ sleep 1
   Performance counter stats for 'system wide':

         506951142      cycles

       1.013879626 seconds time elapsed

where, cycles has an event coding of 0xff. This patch also removes
the unnecessary 'event' mask in pmu_write_register, since the config_base
is set by the pmu code after the event is validated.

Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:45:02 +00:00
Suzuki K. Poulose
ee8e5d5fbe arm-cci: Split the code for PMU vs driver support
This patch separates the PMU driver code from the low level
CCI driver code and enables the PMU driver for ARM64.

Introduces config options for both.

 ARM_CCI400_PORT_CTRL	- controls the low level driver code for
			  CCI400 ports.
 ARM_CCI400_PMU		- controls the PMU driver code
 ARM_CCI400_COMMON	- Common defintions for CCI400

This patch also changes:
 ARM_CCI - common code for probing the CCI devices. This can be
   used for adding support for newer CCI versions(e.g, CCI-500).

Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Abhilash Kesavan <a.kesavan@samsung.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:44:43 +00:00
Suzuki K. Poulose
772742a6c7 arm-cci: Get rid of secure transactions for PMU driver
Avoid secure transactions while probing the CCI PMU. The
existing code makes use of the Peripheral ID2 (PID2) register
to determine the revision of the CCI400, which requires a
secure transaction. This puts a limitation on the usage of the
driver on systems running non-secure Linux(e.g, ARM64).

Updated the device-tree binding for cci pmu node to add the explicit
revision number for the compatible field.

The supported strings are :
	arm,cci-400-pmu,r0
	arm,cci-400-pmu,r1
	arm,cci-400-pmu - DEPRECATED. See NOTE below

NOTE: If the revision is not mentioned, we need to probe the cci revision,
which could be fatal on a platform running non-secure. We need a reliable way
to know if we can poke the CCI registers at runtime on ARM32. We depend on
'mcpm_is_available()' when it is available. mcpm_is_available() returns true
only when there is a registered driver for mcpm. Otherwise, we assume that we
don't have secure access, and skips probing the revision number(ARM64 case).

The MCPM should figure out if it is safe to access the CCI. Unfortunately
there isn't a reliable way to indicate the same via dtb. This patch doesn't
address/change the current situation. It only deals with the CCI-PMU, leaving
the assumptions about the secure access as it has been, prior to this patch.

Cc: devicetree@vger.kernel.org
Cc: Punit Agrawal <punit.agrawal@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:44:35 +00:00
Suzuki K. Poulose
fc17c83944 arm-cci: Abstract the CCI400 PMU specific definitions
CCI400 has different event specifications for PMU, for revsion
0 and revision 1. As of now, we check the revision every single
time before using the parameters for the PMU. This patch abstracts
the details of the pmu models in a struct (cci_pmu_model) and
stores the information in cci_pmu at initialisation time, avoiding
multiple probe operations.

Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:44:24 +00:00
Suzuki K. Poulose
f6b9e83ce0 arm-cci: Rearrange code for splitting PMU vs driver code
No functional changes, only code re-arrangements for easier split of the
PMU code vs low level driver code. Extracts the port handling code
to cci_probe_ports().

Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:44:15 +00:00
Suzuki K. Poulose
b1862199be drivers: cci: reject groups spanning multiple HW PMUs
The perf core implicitly rejects events spanning multiple HW PMUs, as in
these cases the event->ctx will differ. However this validation is
performed after pmu::event_init() is called in perf_init_event(), and
thus pmu::event_init() may be called with a group leader from a
different HW PMU.

The CCI PMU driver does not take this fact into account, and assumes
that the any other hardware event belongs to the CCI. There are two
issues with it :

1) It is wrong and we should reject such groups.
2) Validation allocates an temporary idx for this non-cci event, which leads
to wrong calculation of the counter availability, and eventually lesser
number of events in the group.

This patch updates the CCI PMU driver to first test for and reject
events from other PMUs, which is the right thing to do.

Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Peter Ziljstra (Intel) <peterz@infradead.org>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27 13:44:11 +00:00
Tejun Heo
660e5ec02d arm: use %*pb[l] to print bitmaps including cpumasks and nodemasks
printk and friends can now format bitmaps using '%*pb[l]'.  cpumask
and nodemask also provide cpumask_pr_args() and nodemask_pr_args()
respectively which can be used to generate the two printf arguments
necessary to format the specified cpu/nodemask.

* Line termination only requires one extra space at the end of the
  buffer.  Use PAGE_SIZE - 1 instead of PAGE_SIZE - 2 when formatting.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-13 21:21:37 -08:00
Abhilash Kesavan
896ddd600b drivers: bus: check cci device tree node status
The arm-cci driver completes the probe sequence even if the cci node is
marked as disabled. Add a check in the driver to honour the cci status
in the device tree.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-01-16 19:10:41 -08:00
Mark Rutland
c6f85cb430 bus: cci: move away from arm_pmu framework
The ARM CPU PMUs and the ARM CCI PMU are using the same framework
despite being substantially different in programming model, which makes
it difficult to handle either particularly well.

This patch migrates the ARM CCI PMU driver away from the arm_pmu
framework, matching the style of the CCN PMU driver and other 'uncore'
PMU drivers. This will enable refactoring of the arm_pmu framework to
better support CPU PMUs. Event context migration on hotplug is not yet
added due to a race on event->ctx in the core perf code.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
[will: fix whitespace issues]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-10-30 12:16:57 +00:00
Himangi Saraogi
fc5130de83 drivers: CCI: Correct use of ! and &
In commit ae91d60ba8, a bug was fixed that
involved converting !x & y to !(x & y).  The code below shows the same
pattern, and thus should perhaps be fixed in the same way.

The Coccinelle semantic patch that makes this change is as follows:

// <smpl>
@@ expression E1,E2; @@
(
  !E1 & !E2
|
- !E1 & E2
+ !(E1 & E2)
)
// </smpl>

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2014-07-30 22:58:54 -07:00
Punit Agrawal
dc4409c006 drivers: cci: Export CCI PMU revision
The event numbering changed between revision r0 and r1 of the CCI
PMU. Expose this to userspace to allow tooling to handle the
differences in event numbers.

Suggested-by: Drew Richardson <Drew.Richardson@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2014-02-25 19:36:17 +01:00
Punit Agrawal
6fb0c4a742 drivers: cci: Extend support to CCI revisions > r1p2
The driver queries the CCI IP revision to distinguish between r0 and r1
scheme for event numbers and currently supports upto version r1p2. To
minimise code churn every time there's a new version of the IP, assume
that event numbering doesn't change for revisions > r1p0 (which is
the case).

The driver will still need an update for future revisions that change
the event numbers.

Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2014-02-25 19:36:16 +01:00
Lorenzo Pieralisi
7c762036e2 drivers: bus: fix CCI driver kcalloc call parameters swap
This patch fixes a bug/typo in the CCI driver kcalloc usage
that inadvertently swapped the parameters order in the
kcalloc call and went unnoticed.

Reported-by: Xia Feng <xiafeng@allwinnertech.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2014-01-31 15:15:13 -08:00
Linus Torvalds
f47671e2d8 Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King:
 "Included in this series are:

   1. BE8 (modern big endian) changes for ARM from Ben Dooks
   2. big.Little support from Nicolas Pitre and Dave Martin
   3. support for LPAE systems with all system memory above 4GB
   4. Perf updates from Will Deacon
   5. Additional prefetching and other performance improvements from Will.
   6. Neon-optimised AES implementation fro Ard.
   7. A number of smaller fixes scattered around the place.

  There is a rather horrid merge conflict in tools/perf - I was never
  notified of the conflict because it originally occurred between Will's
  tree and other stuff.  Consequently I have a resolution which Will
  forwarded me, which I'll forward on immediately after sending this
  mail.

  The other notable thing is I'm expecting some build breakage in the
  crypto stuff on ARM only with Ard's AES patches.  These were merged
  into a stable git branch which others had already pulled, so there's
  little I can do about this.  The problem is caused because these
  patches have a dependency on some code in the crypto git tree - I
  tried requesting a branch I can pull to resolve these, and all I got
  each time from the crypto people was "we'll revert our patches then"
  which would only make things worse since I still don't have the
  dependent patches.  I've no idea what's going on there or how to
  resolve that, and since I can't split these patches from the rest of
  this pull request, I'm rather stuck with pushing this as-is or
  reverting Ard's patches.

  Since it should "come out in the wash" I've left them in - the only
  build problems they seem to cause at the moment are with randconfigs,
  and since it's a new feature anyway.  However, if by -rc1 the
  dependencies aren't in, I think it'd be best to revert Ard's patches"

I resolved the perf conflict roughly as per the patch sent by Russell,
but there may be some differences.  Any errors are likely mine.  Let's
see how the crypto issues work out..

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (110 commits)
  ARM: 7868/1: arm/arm64: remove atomic_clear_mask() in "include/asm/atomic.h"
  ARM: 7867/1: include: asm: use 'int' instead of 'unsigned long' for 'oldval' in atomic_cmpxchg().
  ARM: 7866/1: include: asm: use 'long long' instead of 'u64' within atomic.h
  ARM: 7871/1: amba: Extend number of IRQS
  ARM: 7887/1: Don't smp_cross_call() on UP devices in arch_irq_work_raise()
  ARM: 7872/1: Support arch_irq_work_raise() via self IPIs
  ARM: 7880/1: Clear the IT state independent of the Thumb-2 mode
  ARM: 7878/1: nommu: Implement dummy early_paging_init()
  ARM: 7876/1: clear Thumb-2 IT state on exception handling
  ARM: 7874/2: bL_switcher: Remove cpu_hotplug_driver_{lock,unlock}()
  ARM: footbridge: fix build warnings for netwinder
  ARM: 7873/1: vfp: clear vfp_current_hw_state for dying cpu
  ARM: fix misplaced arch_virt_to_idmap()
  ARM: 7848/1: mcpm: Implement cpu_kill() to synchronise on powerdown
  ARM: 7847/1: mcpm: Factor out logical-to-physical CPU translation
  ARM: 7869/1: remove unused XSCALE_PMU Kconfig param
  ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t
  ARM: 7863/1: Let arm_add_memory() always use 64-bit arguments
  ARM: 7862/1: pcpu: replace __get_cpu_var_uses
  ARM: 7861/1: cacheflush: consolidate single-CPU ARMv7 cache disabling code
  ...
2013-11-14 08:51:29 +09:00
Victor Kamensky
fdb07aee0b ARM: cci driver need big endian fixes in asm code
cci_enable_port_for_self written in asm and it works with h/w
registers that are in little endian format. When run in big
endian mode it needs byteswaped constants before/after it
writes/reads to/from such registers

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
2013-10-19 20:46:36 +01:00
Wei Yongjun
fee4f2c66a drivers: CCI: fix the error handle in cci_pmu_probe()
This patch fix the error handle of function cci_pmu_probe():
- using IS_ERR() instead of NULL test for the return value of
  devm_ioremap_resource() since it nerver return NULL.
- remove kfree() for devm_kzalloc allocated memory
- remove dev_warn() since devm_ioremap_resource() has error message
  already.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-09-24 14:03:05 +01:00
Punit Agrawal
b91c8f284a drivers: CCI: add ARM CCI PMU support
Extend the existing CCI driver to support the PMU by registering a perf
backend for it.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Dave Martin <dave.martin@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
[will: removed broken __init annotations]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-09-17 12:02:16 +01:00
Sudeep KarkadaNagesha
78b4d6e0fd drivers/bus: arm-cci: avoid parsing DT for cpu device nodes
Since the CPU device nodes can be retrieved using arch_of_get_cpu_node,
we can use it to avoid parsing the cpus node searching the cpu nodes and
mapping to logical index.

This patch removes parsing DT for cpu nodes by using of_get_cpu_node.

Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
2013-08-21 10:29:53 +01:00
Arnd Bergmann
f490249262 drivers/bus: arm-cci: fix combined ARMv6+v7 build
When we build a kernel with support for both ARMv6 and ARMv7,
gas is trying to be helpful by pointing out that the arm-cci
driver would not work on ARMv6:

/tmp/ccu1LDeU.s: Assembler messages:
/tmp/ccu1LDeU.s:450: Error: selected processor does not support ARM mode `wfi '
/tmp/ccu1LDeU.s:451: Error: selected processor does not support ARM mode `wfe '
make[4]: *** [drivers/bus/arm-cci.o] Error 1

We know that the driver will only be used on ARMv7, hence we
can annotate the inline assembly listing to allow those instructions.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: Dave Martin <dave.martin@linaro.org>
2013-06-03 15:26:08 +02:00
Nicolas Pitre
62158f817a drivers/bus: arm-cci: function to enable CCI ports from early boot code
This provides cci_enable_port_for_self().  This is the counterpart to
cci_disable_port_by_cpu(self).

This is meant to be called from the MCPM machine specific power_up_setup
callback code when the appropriate affinity level needs to be initialized.
The code therefore has to be position independent as the MMU is still off
and it cannot rely on any stack space.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Dave Martin <dave.martin@linaro.org>
2013-05-29 15:50:34 -04:00
Lorenzo Pieralisi
ed69bdd8fd drivers: bus: add ARM CCI support
On ARM multi-cluster systems coherency between cores running on
different clusters is managed by the cache-coherent interconnect (CCI).
It allows broadcasting of TLB invalidates and memory barriers and it
guarantees cache coherency at system level through snooping of slave
interfaces connected to it.

This patch enables the basic infrastructure required in Linux to handle and
programme the CCI component.

Non-local variables used by the CCI management functions called by power
down function calls after disabling the cache must be flushed out to main
memory in advance, otherwise incoherency of those values may occur if they
are sitting in the cache of some other CPU when power down functions
execute. Driver code ensures that relevant data structures are flushed
from inner and outer caches after the driver probe is completed.

CCI slave port resources are linked to set of CPUs through bus masters
phandle properties that link the interface resources to masters node in
the device tree.

Documentation describing the CCI DT bindings is provided with the patch.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2013-05-29 15:50:34 -04:00