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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-26 14:54:29 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-26 14:54:29 -0400
commitf5dcb68086ba2e033b2af32b0da0c7a7c7872a09 (patch)
tree89c41089b492f8d8d411185bd7cb07538802e837 /Documentation/arm
parent3d9f96d850e4bbfae24dc9aee03033dd77c81596 (diff)
parent4af34b572a85c44c55491a10693535a79627c478 (diff)
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Kevin Hilman: "Some of these are for drivers/soc, where we're now putting SoC-specific drivers these days. Some are for other driver subsystems where we have received acks from the appropriate maintainers. Some highlights: - simple-mfd: document DT bindings and misc updates - migrate mach-berlin to simple-mfd for clock, pinctrl and reset - memory: support for Tegra132 SoC - memory: introduce tegra EMC driver for scaling memory frequency - misc. updates for ARM CCI and CCN busses" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (48 commits) drivers: soc: sunxi: Introduce SoC driver to map SRAMs arm-cci: Add aliases for PMU events arm-cci: Add CCI-500 PMU support arm-cci: Sanitise CCI400 PMU driver specific code arm-cci: Abstract handling for CCI events arm-cci: Abstract out the PMU counter details arm-cci: Cleanup PMU driver code arm-cci: Do not enable CCI-400 PMU by default firmware: qcom: scm: Add HDCP Support ARM: berlin: add an ADC node for the BG2Q ARM: berlin: remove useless chip and system ctrl compatibles clk: berlin: drop direct of_iomap of nodes reg property ARM: berlin: move BG2Q clock node ARM: berlin: move BG2CD clock node ARM: berlin: move BG2 clock node clk: berlin: prepare simple-mfd conversion pinctrl: berlin: drop SoC stub provided regmap ARM: berlin: move pinctrl to simple-mfd nodes pinctrl: berlin: prepare to use regmap provided by syscon reset: berlin: drop arch_initcall initialization ...
Diffstat (limited to 'Documentation/arm')
-rw-r--r--Documentation/arm/CCN.txt17
1 files changed, 10 insertions, 7 deletions
diff --git a/Documentation/arm/CCN.txt b/Documentation/arm/CCN.txt
index 0632b3aad83e..ffca443a19b4 100644
--- a/Documentation/arm/CCN.txt
+++ b/Documentation/arm/CCN.txt
@@ -33,20 +33,23 @@ directory, with first 8 configurable by user and additional
33Cycle counter is described by a "type" value 0xff and does 33Cycle counter is described by a "type" value 0xff and does
34not require any other settings. 34not require any other settings.
35 35
36The driver also provides a "cpumask" sysfs attribute, which contains
37a single CPU ID, of the processor which will be used to handle all
38the CCN PMU events. It is recommended that the user space tools
39request the events on this processor (if not, the perf_event->cpu value
40will be overwritten anyway). In case of this processor being offlined,
41the events are migrated to another one and the attribute is updated.
42
36Example of perf tool use: 43Example of perf tool use:
37 44
38/ # perf list | grep ccn 45/ # perf list | grep ccn
39 ccn/cycles/ [Kernel PMU event] 46 ccn/cycles/ [Kernel PMU event]
40<...> 47<...>
41 ccn/xp_valid_flit/ [Kernel PMU event] 48 ccn/xp_valid_flit,xp=?,port=?,vc=?,dir=?/ [Kernel PMU event]
42<...> 49<...>
43 50
44/ # perf stat -C 0 -e ccn/cycles/,ccn/xp_valid_flit,xp=1,port=0,vc=1,dir=1/ \ 51/ # perf stat -a -e ccn/cycles/,ccn/xp_valid_flit,xp=1,port=0,vc=1,dir=1/ \
45 sleep 1 52 sleep 1
46 53
47The driver does not support sampling, therefore "perf record" will 54The driver does not support sampling, therefore "perf record" will
48not work. Also notice that only single cpu is being selected 55not work. Per-task (without "-a") perf sessions are not supported.
49("-C 0") - this is because perf framework does not support
50"non-CPU related" counters (yet?) so system-wide session ("-a")
51would try (and in most cases fail) to set up the same event
52per each CPU.