Re: [RESEND PATCH V4 0/4] Introduce CoreSight STM support
From: Chunyan Zhang
Date: Sun Mar 27 2016 - 22:58:36 EST
On Fri, Mar 25, 2016 at 8:51 PM, Mathieu Poirier
> On 7 March 2016 at 23:33, Chunyan Zhang <zhang.chunyan@xxxxxxxxxx> wrote:
>> This patchset adds support for the CoreSight STM IP block.
>> In the fourth version, comments from various people have been
>> addressed. Representing configurations where channels are shared
>> between multiple masterIDs has been kept unchanged from the previous
>> version because a viable alternative hasn't been suggested.
>> This RESEND PATCH 1/4 depends on the patch  which has been
>> merged into linux-next.
> We are not going anywhere with 1/4. Since the functionality conveyed
> by that patch isn't strictly needed simply drop it (along with 2/4).
> Please take into consideration the comments I made on 4/4 and respin
> on 4.6-rc1 when it comes out.
Got it. Noticed 4.6-rc1 has been came out, I will send out a new
patchset today, include 3/4 and 4/4 with addressing your comments on
Thanks for your review,
>> Changes from V3:
>> - Removed ioctl get_options interface from the generic STM code and CoreSight STM driver.
>> - Removed 'write_max' from the structure 'stm_drvdata', and changed 'write_64bit' to 'write_bytes'.
>> - Revised stm_fundamental_data_size() to return the fundamental data size instead of 0/1.
>> - Removed stm_remove() from the driver.
>> - Revised the return value of ::packet() callback function according to .
>> - Modified stm_send() to send one STP packet at a time.
>> - Added comments to invariant/guaranteed CoreSight STM transaction mode.
>> Changes from V2:
>> - Changed to return -EFAULT if failed on the command STP_GET_OPTIONS.
>> - Used Alex's patch  instead of the last 2/6.
>> - Removed the while loop from stm_send(), since the packet size passed
>> to it isn't larger than 4 bytes on 32-bit system and 8 bytes on
>> 64-bit system.
>> - Removed stm_send_64bit(), since the process of packets on 64-bit
>> CS-STM should be basically the same with on 32-bit system, except the
>> maximum length of writing STM at a time.
>> - Removed the support of writing 64-bit to CoreSight STM buffer at a time
>> on 32-bit ARM architecture according to an ARM engineer suggestion. As
>> he said that the STM might receive a 64-bit write, or might receive a
>> pair of 32-bit writes to the two addressed words in either order.
>> So 64-bit write isn't guaranteed to work on the ARM 32-bit architecture.
>> Changes from v1:
>> - Added a definition of coresight_simple_func() in CS-STM driver to
>> avoid the kbuild test robot error for the time being. This
>> modification will be removed when merging the code in which the
>> coresight_simple_func() has been moved to the header file.
>> - Calculate the channel number according to the channel memory space size.
>>  https://lkml.org/lkml/2016/2/4/652
>>  https://lkml.org/lkml/2016/2/12/397
>>  https://lkml.org/lkml/2015/12/22/348
>> Chunyan Zhang (1):
>> Documentations: Add explanations of the case for non-configurable
>> Mathieu Poirier (2):
>> stm class: provision for statically assigned masterIDs
>> coresight-stm: Bindings for System Trace Macrocell
>> Pratik Patel (1):
>> coresight-stm: adding driver for CoreSight STM component
>> .../ABI/testing/sysfs-bus-coresight-devices-stm | 53 ++
>> .../devicetree/bindings/arm/coresight.txt | 28 +
>> Documentation/trace/coresight.txt | 37 +-
>> Documentation/trace/stm.txt | 6 +
>> drivers/hwtracing/coresight/Kconfig | 11 +
>> drivers/hwtracing/coresight/Makefile | 1 +
>> drivers/hwtracing/coresight/coresight-stm.c | 890 +++++++++++++++++++++
>> drivers/hwtracing/stm/core.c | 17 +-
>> drivers/hwtracing/stm/policy.c | 18 +-
>> include/linux/coresight-stm.h | 6 +
>> include/linux/stm.h | 8 +
>> include/uapi/linux/coresight-stm.h | 21 +
>> 12 files changed, 1090 insertions(+), 6 deletions(-)
>> create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
>> create mode 100644 drivers/hwtracing/coresight/coresight-stm.c
>> create mode 100644 include/linux/coresight-stm.h
>> create mode 100644 include/uapi/linux/coresight-stm.h