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2015-05-29arm-cci: Add aliases for PMU eventsSuzuki K. Poulose1-1/+295
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>
2015-05-29arm-cci: Add CCI-500 PMU supportSuzuki K. Poulose1-0/+133
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>
2015-05-29arm-cci: Sanitise CCI400 PMU driver specific codeSuzuki K. Poulose1-65/+92
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>
2015-05-29arm-cci: Abstract handling for CCI eventsSuzuki K. Poulose1-23/+55
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>
2015-05-29arm-cci: Abstract out the PMU counter detailsSuzuki K. Poulose1-30/+93
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>
2015-05-29arm-cci: Cleanup PMU driver codeSuzuki K. Poulose1-62/+80
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>
2015-05-07drivers: CCI: fix used_mask init in validate_group()Mark Salter1-1/+1
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>
2015-03-27arm-cci: Fix CCI PMU event validationSuzuki K. Poulose1-5/+7
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>
2015-03-27arm-cci: Split the code for PMU vs driver supportSuzuki K. Poulose1-4/+20
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>
2015-03-27arm-cci: Get rid of secure transactions for PMU driverSuzuki K. Poulose1-1/+16
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>
2015-03-27arm-cci: Abstract the CCI400 PMU specific definitionsSuzuki K. Poulose1-60/+81
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>
2015-03-27arm-cci: Rearrange code for splitting PMU vs driver codeSuzuki K. Poulose1-163/+163
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>
2015-03-27drivers: cci: reject groups spanning multiple HW PMUsSuzuki K. Poulose1-5/+14
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>
2015-02-13arm: use %*pb[l] to print bitmaps including cpumasks and nodemasksTejun Heo1-2/+2
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>
2015-01-16drivers: bus: check cci device tree node statusAbhilash Kesavan1-0/+3
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>
2014-10-30bus: cci: move away from arm_pmu frameworkMark Rutland1-108/+444
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>
2014-07-30drivers: CCI: Correct use of ! and &Himangi Saraogi1-1/+2
In commit ae91d60ba88ef0bdb1b5e9b2363bd52fc45d2af7, 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>
2014-02-25drivers: cci: Export CCI PMU revisionPunit Agrawal1-2/+10
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>
2014-02-25drivers: cci: Extend support to CCI revisions > r1p2Punit Agrawal1-9/+3
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>
2014-01-31drivers: bus: fix CCI driver kcalloc call parameters swapLorenzo Pieralisi1-1/+1
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>
2013-11-14Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-armLinus Torvalds1-2/+4
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 ...
2013-10-19ARM: cci driver need big endian fixes in asm codeVictor Kamensky1-2/+4
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>
2013-09-24drivers: CCI: fix the error handle in cci_pmu_probe()Wei Yongjun1-26/+7
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>
2013-09-17drivers: CCI: add ARM CCI PMU supportPunit Agrawal1-4/+632
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>
2013-08-21drivers/bus: arm-cci: avoid parsing DT for cpu device nodesSudeep KarkadaNagesha1-21/+7
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>
2013-06-03drivers/bus: arm-cci: fix combined ARMv6+v7 buildArnd Bergmann1-1/+1
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>
2013-05-29drivers/bus: arm-cci: function to enable CCI ports from early boot codeNicolas Pitre1-6/+113
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>
2013-05-29drivers: bus: add ARM CCI supportLorenzo Pieralisi1-0/+426
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>