| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Tue, 9 Jul 2019 23:41:58 +0700
From: Phong Tran <tranmanphong@...il.com>
To: corbet@....net, mathieu.poirier@...aro.org, leo.yan@...aro.org
Cc: linux-arm-kernel@...ts.infradead.org, linux-doc@...r.kernel.org,
linux-kernel-mentees@...ts.linuxfoundation.org,
linux-kernel@...r.kernel.org, mchehab@...nel.org,
skhan@...uxfoundation.org, suzuki.poulose@....com,
tranmanphong@...il.com
Subject: [Patch V2] Documentation: coresight: covert txt to rst
as doc-guide of kernel documentation, use Sphinx tool to
generate the html/pdf... files.
This changes the plan text txt to rst format.
Signed-off-by: Phong Tran <tranmanphong@...il.com>
---
ChangeLog:
V2:
* Add coresight-cpu-debug
* Update MAINTAINERS file
* Avoid use markup as much as posible
---
...sight-cpu-debug.txt => coresight-cpu-debug.rst} | 63 ++--
.../trace/{coresight.txt => coresight.rst} | 352 +++++++++++----------
Documentation/trace/index.rst | 2 +
MAINTAINERS | 4 +-
4 files changed, 229 insertions(+), 192 deletions(-)
rename Documentation/trace/{coresight-cpu-debug.txt => coresight-cpu-debug.rst} (84%)
rename Documentation/trace/{coresight.txt => coresight.rst} (55%)
diff --git a/Documentation/trace/coresight-cpu-debug.txt b/Documentation/trace/coresight-cpu-debug.rst
similarity index 84%
rename from Documentation/trace/coresight-cpu-debug.txt
rename to Documentation/trace/coresight-cpu-debug.rst
index f07e38094b40..b219d75f4f8a 100644
--- a/Documentation/trace/coresight-cpu-debug.txt
+++ b/Documentation/trace/coresight-cpu-debug.rst
@@ -1,5 +1,6 @@
- Coresight CPU Debug Module
- ==========================
+==========================
+Coresight CPU Debug Module
+==========================
Author: Leo Yan <leo.yan@...aro.org>
Date: April 5th, 2017
@@ -69,6 +70,7 @@ Before accessing debug registers, we should ensure the clock and power domain
have been enabled properly. In ARMv8-a ARM (ARM DDI 0487A.k) chapter 'H9.1
Debug registers', the debug registers are spread into two domains: the debug
domain and the CPU domain.
+::
+---------------+
| |
@@ -125,18 +127,21 @@ If you want to enable debugging functionality at boot time, you can add
"coresight_cpu_debug.enable=1" to the kernel command line parameter.
The driver also can work as module, so can enable the debugging when insmod
-module:
-# insmod coresight_cpu_debug.ko debug=1
+module::
+
+ # insmod coresight_cpu_debug.ko debug=1
When boot time or insmod module you have not enabled the debugging, the driver
uses the debugfs file system to provide a knob to dynamically enable or disable
debugging:
-To enable it, write a '1' into /sys/kernel/debug/coresight_cpu_debug/enable:
-# echo 1 > /sys/kernel/debug/coresight_cpu_debug/enable
+To enable it, write a '1' into /sys/kernel/debug/coresight_cpu_debug/enable::
+
+ # echo 1 > /sys/kernel/debug/coresight_cpu_debug/enable
+
+To disable it, write a '0' into /sys/kernel/debug/coresight_cpu_debug/enable::
-To disable it, write a '0' into /sys/kernel/debug/coresight_cpu_debug/enable:
-# echo 0 > /sys/kernel/debug/coresight_cpu_debug/enable
+ # echo 0 > /sys/kernel/debug/coresight_cpu_debug/enable
As explained in chapter "Clock and power domain", if you are working on one
platform which has idle states to power off debug logic and the power
@@ -154,34 +159,34 @@ subsystem, more specifically by using the "/dev/cpu_dma_latency"
interface (see Documentation/power/pm_qos_interface.txt for more
details). As specified in the PM QoS documentation the requested
parameter will stay in effect until the file descriptor is released.
-For example:
+For example::
-# exec 3<> /dev/cpu_dma_latency; echo 0 >&3
-...
-Do some work...
-...
-# exec 3<>-
+ # exec 3<> /dev/cpu_dma_latency; echo 0 >&3
+ ...
+ Do some work...
+ ...
+ # exec 3<>-
The same can also be done from an application program.
Disable specific CPU's specific idle state from cpuidle sysfs (see
-Documentation/admin-guide/pm/cpuidle.rst):
-# echo 1 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$state/disable
+Documentation/admin-guide/pm/cpuidle.rst)::
+ # echo 1 > /sys/devices/system/cpu/cpu$cpu/cpuidle/state$state/disable
Output format
-------------
-Here is an example of the debugging output format:
-
-ARM external debug module:
-coresight-cpu-debug 850000.debug: CPU[0]:
-coresight-cpu-debug 850000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock)
-coresight-cpu-debug 850000.debug: EDPCSR: handle_IPI+0x174/0x1d8
-coresight-cpu-debug 850000.debug: EDCIDSR: 00000000
-coresight-cpu-debug 850000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)
-coresight-cpu-debug 852000.debug: CPU[1]:
-coresight-cpu-debug 852000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock)
-coresight-cpu-debug 852000.debug: EDPCSR: debug_notifier_call+0x23c/0x358
-coresight-cpu-debug 852000.debug: EDCIDSR: 00000000
-coresight-cpu-debug 852000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)
+Here is an example of the debugging output format::
+
+ ARM external debug module:
+ coresight-cpu-debug 850000.debug: CPU[0]:
+ coresight-cpu-debug 850000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock)
+ coresight-cpu-debug 850000.debug: EDPCSR: handle_IPI+0x174/0x1d8
+ coresight-cpu-debug 850000.debug: EDCIDSR: 00000000
+ coresight-cpu-debug 850000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)
+ coresight-cpu-debug 852000.debug: CPU[1]:
+ coresight-cpu-debug 852000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock)
+ coresight-cpu-debug 852000.debug: EDPCSR: debug_notifier_call+0x23c/0x358
+ coresight-cpu-debug 852000.debug: EDCIDSR: 00000000
+ coresight-cpu-debug 852000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0)
diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.rst
similarity index 55%
rename from Documentation/trace/coresight.txt
rename to Documentation/trace/coresight.rst
index efbc832146e7..fc9486b7bd87 100644
--- a/Documentation/trace/coresight.txt
+++ b/Documentation/trace/coresight.rst
@@ -1,5 +1,6 @@
- Coresight - HW Assisted Tracing on ARM
- ======================================
+======================================
+Coresight - HW Assisted Tracing on ARM
+======================================
Author: Mathieu Poirier <mathieu.poirier@...aro.org>
Date: September 11th, 2014
@@ -26,7 +27,7 @@ implementation, either storing the compressed stream in a memory buffer or
creating an interface to the outside world where data can be transferred to a
host without fear of filling up the onboard coresight memory buffer.
-At typical coresight system would look like this:
+At typical coresight system would look like this::
*****************************************************************
**************************** AMBA AXI ****************************===||
@@ -93,17 +94,17 @@ intricate IP blocks such as STM and CTI.
Acronyms and Classification
---------------------------
-Acronyms:
+Acronyms::
-PTM: Program Trace Macrocell
-ETM: Embedded Trace Macrocell
-STM: System trace Macrocell
-ETB: Embedded Trace Buffer
-ITM: Instrumentation Trace Macrocell
-TPIU: Trace Port Interface Unit
-TMC-ETR: Trace Memory Controller, configured as Embedded Trace Router
-TMC-ETF: Trace Memory Controller, configured as Embedded Trace FIFO
-CTI: Cross Trigger Interface
+ PTM: Program Trace Macrocell
+ ETM: Embedded Trace Macrocell
+ STM: System trace Macrocell
+ ETB: Embedded Trace Buffer
+ ITM: Instrumentation Trace Macrocell
+ TPIU: Trace Port Interface Unit
+ TMC-ETR: Trace Memory Controller, configured as Embedded Trace Router
+ TMC-ETF: Trace Memory Controller, configured as Embedded Trace FIFO
+ CTI: Cross Trigger Interface
Classification:
@@ -118,7 +119,7 @@ Misc:
Device Tree Bindings
-----------------------
+--------------------
See Documentation/devicetree/bindings/arm/coresight.txt for details.
@@ -133,57 +134,79 @@ The coresight framework provides a central point to represent, configure and
manage coresight devices on a platform. Any coresight compliant device can
register with the framework for as long as they use the right APIs:
-struct coresight_device *coresight_register(struct coresight_desc *desc);
-void coresight_unregister(struct coresight_device *csdev);
+.. c:function:: struct coresight_device *coresight_register(struct coresight_desc *desc);
+.. c:function:: void coresight_unregister(struct coresight_device *csdev);
-The registering function is taking a "struct coresight_device *csdev" and
-register the device with the core framework. The unregister function takes
-a reference to a "struct coresight_device", obtained at registration time.
+The registering function is taking a
+::
+
+ struct coresight_desc *desc
+
+and register the device with the core framework. The unregister function takes
+a reference to a
+::
+
+ struct coresight_device *csdev
+
+The pointer csdev obtained at registration time.
If everything goes well during the registration process the new devices will
-show up under /sys/bus/coresight/devices, as showns here for a TC2 platform:
+show up under /sys/bus/coresight/devices, as showns here for a TC2 platform::
-root:~# ls /sys/bus/coresight/devices/
-replicator 20030000.tpiu 2201c000.ptm 2203c000.etm 2203e000.etm
-20010000.etb 20040000.funnel 2201d000.ptm 2203d000.etm
-root:~#
+ root:~# ls /sys/bus/coresight/devices/
+ replicator 20030000.tpiu 2201c000.ptm 2203c000.etm 2203e000.etm
+ 20010000.etb 20040000.funnel 2201d000.ptm 2203d000.etm
+ root:~#
-The functions take a "struct coresight_device", which looks like this:
+The functions take a struct coresight_device, which looks like this::
-struct coresight_desc {
- enum coresight_dev_type type;
- struct coresight_dev_subtype subtype;
- const struct coresight_ops *ops;
- struct coresight_platform_data *pdata;
- struct device *dev;
- const struct attribute_group **groups;
-};
+ struct coresight_desc {
+ enum coresight_dev_type type;
+ struct coresight_dev_subtype subtype;
+ const struct coresight_ops *ops;
+ struct coresight_platform_data *pdata;
+ struct device *dev;
+ const struct attribute_group **groups;
+ };
The "coresight_dev_type" identifies what the device is, i.e, source link or
sink while the "coresight_dev_subtype" will characterise that type further.
-The "struct coresight_ops" is mandatory and will tell the framework how to
+The struct coresight_ops is mandatory and will tell the framework how to
perform base operations related to the components, each component having
-a different set of requirement. For that "struct coresight_ops_sink",
-"struct coresight_ops_link" and "struct coresight_ops_source" have been
+a different set of requirement. For that struct coresight_ops_sink,
+struct coresight_ops_link and struct coresight_ops_source have been
provided.
-The next field, "struct coresight_platform_data *pdata" is acquired by calling
-"of_get_coresight_platform_data()", as part of the driver's _probe routine and
-"struct device *dev" gets the device reference embedded in the "amba_device":
+The next field
+::
+
+ struct coresight_platform_data *pdata
+
+is acquired by calling of_get_coresight_platform_data(), as part of
+the driver's _probe routine and
+::
-static int etm_probe(struct amba_device *adev, const struct amba_id *id)
-{
- ...
- ...
- drvdata->dev = &adev->dev;
- ...
-}
+ struct device *dev
+
+gets the device reference embedded in the amba_device::
+
+ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
+ {
+ ...
+ ...
+ drvdata->dev = &adev->dev;
+ ...
+ }
Specific class of device (source, link, or sink) have generic operations
-that can be performed on them (see "struct coresight_ops"). The
-"**groups" is a list of sysfs entries pertaining to operations
+that can be performed on them (see struct coresight_ops). The
+::
+
+ const struct attribute_group **groups
+
+is a list of sysfs entries pertaining to operations
specific to that component only. "Implementation defined" customisations are
expected to be accessed and controlled using those entries.
@@ -191,9 +214,12 @@ expected to be accessed and controlled using those entries.
How to use the tracer modules
-----------------------------
-There are two ways to use the Coresight framework: 1) using the perf cmd line
-tools and 2) interacting directly with the Coresight devices using the sysFS
-interface. Preference is given to the former as using the sysFS interface
+There are two ways to use the Coresight framework:
+
+1. using the perf cmd line tools.
+2. interacting directly with the Coresight devices using the sysFS interface.
+
+Preference is given to the former as using the sysFS interface
requires a deep understanding of the Coresight HW. The following sections
provide details on using both methods.
@@ -202,107 +228,107 @@ provide details on using both methods.
Before trace collection can start, a coresight sink needs to be identified.
There is no limit on the amount of sinks (nor sources) that can be enabled at
any given moment. As a generic operation, all device pertaining to the sink
-class will have an "active" entry in sysfs:
-
-root:/sys/bus/coresight/devices# ls
-replicator 20030000.tpiu 2201c000.ptm 2203c000.etm 2203e000.etm
-20010000.etb 20040000.funnel 2201d000.ptm 2203d000.etm
-root:/sys/bus/coresight/devices# ls 20010000.etb
-enable_sink status trigger_cntr
-root:/sys/bus/coresight/devices# echo 1 > 20010000.etb/enable_sink
-root:/sys/bus/coresight/devices# cat 20010000.etb/enable_sink
-1
-root:/sys/bus/coresight/devices#
+class will have an "active" entry in sysfs::
+
+ root:/sys/bus/coresight/devices# ls
+ replicator 20030000.tpiu 2201c000.ptm 2203c000.etm 2203e000.etm
+ 20010000.etb 20040000.funnel 2201d000.ptm 2203d000.etm
+ root:/sys/bus/coresight/devices# ls 20010000.etb
+ enable_sink status trigger_cntr
+ root:/sys/bus/coresight/devices# echo 1 > 20010000.etb/enable_sink
+ root:/sys/bus/coresight/devices# cat 20010000.etb/enable_sink
+ 1
+ root:/sys/bus/coresight/devices#
At boot time the current etm3x driver will configure the first address
comparator with "_stext" and "_etext", essentially tracing any instruction
that falls within that range. As such "enabling" a source will immediately
-trigger a trace capture:
-
-root:/sys/bus/coresight/devices# echo 1 > 2201c000.ptm/enable_source
-root:/sys/bus/coresight/devices# cat 2201c000.ptm/enable_source
-1
-root:/sys/bus/coresight/devices# cat 20010000.etb/status
-Depth: 0x2000
-Status: 0x1
-RAM read ptr: 0x0
-RAM wrt ptr: 0x19d3 <----- The write pointer is moving
-Trigger cnt: 0x0
-Control: 0x1
-Flush status: 0x0
-Flush ctrl: 0x2001
-root:/sys/bus/coresight/devices#
-
-Trace collection is stopped the same way:
-
-root:/sys/bus/coresight/devices# echo 0 > 2201c000.ptm/enable_source
-root:/sys/bus/coresight/devices#
-
-The content of the ETB buffer can be harvested directly from /dev:
-
-root:/sys/bus/coresight/devices# dd if=/dev/20010000.etb \
-of=~/cstrace.bin
-
-64+0 records in
-64+0 records out
-32768 bytes (33 kB) copied, 0.00125258 s, 26.2 MB/s
-root:/sys/bus/coresight/devices#
+trigger a trace capture::
+
+ root:/sys/bus/coresight/devices# echo 1 > 2201c000.ptm/enable_source
+ root:/sys/bus/coresight/devices# cat 2201c000.ptm/enable_source
+ 1
+ root:/sys/bus/coresight/devices# cat 20010000.etb/status
+ Depth: 0x2000
+ Status: 0x1
+ RAM read ptr: 0x0
+ RAM wrt ptr: 0x19d3 <----- The write pointer is moving
+ Trigger cnt: 0x0
+ Control: 0x1
+ Flush status: 0x0
+ Flush ctrl: 0x2001
+ root:/sys/bus/coresight/devices#
+
+Trace collection is stopped the same way::
+
+ root:/sys/bus/coresight/devices# echo 0 > 2201c000.ptm/enable_source
+ root:/sys/bus/coresight/devices#
+
+The content of the ETB buffer can be harvested directly from /dev::
+
+ root:/sys/bus/coresight/devices# dd if=/dev/20010000.etb \
+ of=~/cstrace.bin
+ 64+0 records in
+ 64+0 records out
+ 32768 bytes (33 kB) copied, 0.00125258 s, 26.2 MB/s
+ root:/sys/bus/coresight/devices#
The file cstrace.bin can be decompressed using "ptm2human", DS-5 or Trace32.
Following is a DS-5 output of an experimental loop that increments a variable up
to a certain value. The example is simple and yet provides a glimpse of the
wealth of possibilities that coresight provides.
-
-Info Tracing enabled
-Instruction 106378866 0x8026B53C E52DE004 false PUSH {lr}
-Instruction 0 0x8026B540 E24DD00C false SUB sp,sp,#0xc
-Instruction 0 0x8026B544 E3A03000 false MOV r3,#0
-Instruction 0 0x8026B548 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Timestamp Timestamp: 17106715833
-Instruction 319 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Instruction 9 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Instruction 7 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Instruction 7 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Instruction 10 0x8026B54C E59D3004 false LDR r3,[sp,#4]
-Instruction 0 0x8026B550 E3530004 false CMP r3,#4
-Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
-Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
-Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
-Instruction 6 0x8026B560 EE1D3F30 false MRC p15,#0x0,r3,c13,c0,#1
-Instruction 0 0x8026B564 E1A0100D false MOV r1,sp
-Instruction 0 0x8026B568 E3C12D7F false BIC r2,r1,#0x1fc0
-Instruction 0 0x8026B56C E3C2203F false BIC r2,r2,#0x3f
-Instruction 0 0x8026B570 E59D1004 false LDR r1,[sp,#4]
-Instruction 0 0x8026B574 E59F0010 false LDR r0,[pc,#16] ; [0x8026B58C] = 0x80550368
-Instruction 0 0x8026B578 E592200C false LDR r2,[r2,#0xc]
-Instruction 0 0x8026B57C E59221D0 false LDR r2,[r2,#0x1d0]
-Instruction 0 0x8026B580 EB07A4CF true BL {pc}+0x1e9344 ; 0x804548c4
-Info Tracing enabled
-Instruction 13570831 0x8026B584 E28DD00C false ADD sp,sp,#0xc
-Instruction 0 0x8026B588 E8BD8000 true LDM sp!,{pc}
-Timestamp Timestamp: 17107041535
+::
+
+ Info Tracing enabled
+ Instruction 106378866 0x8026B53C E52DE004 false PUSH {lr}
+ Instruction 0 0x8026B540 E24DD00C false SUB sp,sp,#0xc
+ Instruction 0 0x8026B544 E3A03000 false MOV r3,#0
+ Instruction 0 0x8026B548 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Timestamp Timestamp: 17106715833
+ Instruction 319 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Instruction 9 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Instruction 7 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Instruction 7 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Instruction 10 0x8026B54C E59D3004 false LDR r3,[sp,#4]
+ Instruction 0 0x8026B550 E3530004 false CMP r3,#4
+ Instruction 0 0x8026B554 E2833001 false ADD r3,r3,#1
+ Instruction 0 0x8026B558 E58D3004 false STR r3,[sp,#4]
+ Instruction 0 0x8026B55C DAFFFFFA true BLE {pc}-0x10 ; 0x8026b54c
+ Instruction 6 0x8026B560 EE1D3F30 false MRC p15,#0x0,r3,c13,c0,#1
+ Instruction 0 0x8026B564 E1A0100D false MOV r1,sp
+ Instruction 0 0x8026B568 E3C12D7F false BIC r2,r1,#0x1fc0
+ Instruction 0 0x8026B56C E3C2203F false BIC r2,r2,#0x3f
+ Instruction 0 0x8026B570 E59D1004 false LDR r1,[sp,#4]
+ Instruction 0 0x8026B574 E59F0010 false LDR r0,[pc,#16] ; [0x8026B58C] = 0x80550368
+ Instruction 0 0x8026B578 E592200C false LDR r2,[r2,#0xc]
+ Instruction 0 0x8026B57C E59221D0 false LDR r2,[r2,#0x1d0]
+ Instruction 0 0x8026B580 EB07A4CF true BL {pc}+0x1e9344 ; 0x804548c4
+ Info Tracing enabled
+ Instruction 13570831 0x8026B584 E28DD00C false ADD sp,sp,#0xc
+ Instruction 0 0x8026B588 E8BD8000 true LDM sp!,{pc}
+ Timestamp Timestamp: 17107041535
2) Using perf framework:
@@ -327,7 +353,7 @@ A Coresight PMU works the same way as any other PMU, i.e the name of the PMU is
listed along with configuration options within forward slashes '/'. Since a
Coresight system will typically have more than one sink, the name of the sink to
work with needs to be specified as an event option. Names for sink to choose
-from are listed in sysFS under ($SYSFS)/bus/coresight/devices:
+from are listed in sysFS under ($SYSFS)/bus/coresight/devices::
root@...aro-nano:~# ls /sys/bus/coresight/devices/
20010000.etf 20040000.funnel 20100000.stm 22040000.etm
@@ -343,14 +369,14 @@ to use for the trace session.
More information on the above and other example on how to use Coresight with
the perf tools can be found in the "HOWTO.md" file of the openCSD gitHub
-repository [3].
+repository [#third]_.
2.1) AutoFDO analysis using the perf tools:
perf can be used to record and analyze trace of programs.
Execution can be recorded using 'perf record' with the cs_etm event,
-specifying the name of the sink to record to, e.g:
+specifying the name of the sink to record to, e.g::
perf record -e cs_etm/@...70000.etr/u --per-thread
@@ -369,12 +395,14 @@ Generating coverage files for Feedback Directed Optimization: AutoFDO
'perf inject' accepts the --itrace option in which case tracing data is
removed and replaced with the synthesized events. e.g.
+::
perf inject --itrace --strip -i perf.data -o perf.data.new
Below is an example of using ARM ETM for autoFDO. It requires autofdo
(https://github.com/google/autofdo) and gcc version 5. The bubble
sort example is from the AutoFDO tutorial (https://gcc.gnu.org/wiki/AutoFDO/Tutorial).
+::
$ gcc-5 -O3 sort.c -o sort
$ taskset -c 2 ./sort
@@ -403,28 +431,30 @@ difference is that clients are driving the trace capture rather
than the program flow through the code.
As with any other CoreSight component, specifics about the STM tracer can be
-found in sysfs with more information on each entry being found in [1]:
+found in sysfs with more information on each entry being found in [#first]_::
-root@...ericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm
-enable_source hwevent_select port_enable subsystem uevent
-hwevent_enable mgmt port_select traceid
-root@...ericarmv8:~#
+ root@...ericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm
+ enable_source hwevent_select port_enable subsystem uevent
+ hwevent_enable mgmt port_select traceid
+ root@...ericarmv8:~#
Like any other source a sink needs to be identified and the STM enabled before
-being used:
+being used::
-root@...ericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink
-root@...ericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source
+ root@...ericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink
+ root@...ericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source
From there user space applications can request and use channels using the devfs
-interface provided for that purpose by the generic STM API:
+interface provided for that purpose by the generic STM API::
+
+ root@...ericarmv8:~# ls -l /dev/20100000.stm
+ crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm
+ root@...ericarmv8:~#
+
+Details on how to use the generic STM API can be found here [#second]_.
-root@...ericarmv8:~# ls -l /dev/20100000.stm
-crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm
-root@...ericarmv8:~#
+.. [#first] Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
-Details on how to use the generic STM API can be found here [2].
+.. [#second] Documentation/trace/stm.rst
-[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
-[2]. Documentation/trace/stm.rst
-[3]. https://github.com/Linaro/perf-opencsd
+.. [#third] https://github.com/Linaro/perf-opencsd
diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst
index 6b4107cf4b98..b7891cb1ab4d 100644
--- a/Documentation/trace/index.rst
+++ b/Documentation/trace/index.rst
@@ -23,3 +23,5 @@ Linux Tracing Technologies
intel_th
stm
sys-t
+ coresight
+ coresight-cpu-debug
diff --git a/MAINTAINERS b/MAINTAINERS
index 558acf24ea1e..04b006e5cc0a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1549,8 +1549,8 @@ R: Suzuki K Poulose <suzuki.poulose@....com>
L: linux-arm-kernel@...ts.infradead.org (moderated for non-subscribers)
S: Maintained
F: drivers/hwtracing/coresight/*
-F: Documentation/trace/coresight.txt
-F: Documentation/trace/coresight-cpu-debug.txt
+F: Documentation/trace/coresight.rst
+F: Documentation/trace/coresight-cpu-debug.rst
F: Documentation/devicetree/bindings/arm/coresight.txt
F: Documentation/devicetree/bindings/arm/coresight-cpu-debug.txt
F: Documentation/ABI/testing/sysfs-bus-coresight-devices-*
--
2.11.0
Powered by blists - more mailing lists