On 2022/12/21 12:02, Bagas Sanjaya wrote:
On Tue, Dec 20, 2022 at 05:29:45PM +0800, Junhao He wrote:
diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb b/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb new file mode 100644 index 000000000000..f6526882c627 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb @@ -0,0 +1,31 @@ +What: /sys/bus/coresight/devices/ultra_smb<N>/enable_sink +Date: December 2022 +KernelVersion: 6.2 +Contact: Junhao He hejunhao3@huawei.com +Description: (RW) Add/remove a SMB device from a trace path. There can be
multiple sources for a single SMB device.+What: /sys/bus/coresight/devices/ultra_smb<N>/mgmt/buf_size +Date: December 2022 +KernelVersion: 6.2 +Contact: Junhao He hejunhao3@huawei.com +Description: (Read) Shows the buffer size of each UltraSoc SMB device.
+What: /sys/bus/coresight/devices/ultra_smb<N>/mgmt/buf_status +Date: December 2022 +KernelVersion: 6.2 +Contact: Junhao He hejunhao3@huawei.com +Description: (Read) Shows the value held by UltraSoc SMB status register.
BIT(0) is zero means buffer is empty.+What: /sys/bus/coresight/devices/ultra_smb<N>/mgmt/read_pos +Date: December 2022 +KernelVersion: 6.2 +Contact: Junhao He hejunhao3@huawei.com +Description: (Read) Shows the value held by UltraSoc SMB Read Pointer register.
+What: /sys/bus/coresight/devices/ultra_smb<N>/mgmt/write_pos +Date: December 2022 +KernelVersion: 6.2 +Contact: Junhao He hejunhao3@huawei.com +Description: (Read) Shows the value held by UltraSoc SMB Write Pointer register.
s/Read/RO/ and s/value held by/value of/
Ok, will fix it.
Thanks.
diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst b/Documentation/trace/coresight/ultrasoc-smb.rst new file mode 100644 index 000000000000..056dd120e14c --- /dev/null +++ b/Documentation/trace/coresight/ultrasoc-smb.rst @@ -0,0 +1,83 @@ +.. SPDX-License-Identifier: GPL-2.0
+====================================== +UltraSoc - HW Assisted Tracing on SoC +======================================
- :Author: Qi Liu liuqi115@huawei.com
- :Date: December 2022
+Introduction +------------
+UltraSoc SMB is a per SCCL (Super CPU Cluster) hardware. It provides a +way to buffer and store CPU trace messages in a region of shared system +memory. The device acts as a coresight sink device and the +corresponding trace generators (ETM) are attached as source devices.
+Sysfs files and directories +---------------------------
+The SMB devices appear on the existing coresight bus alongside other +devices::
- $# ls /sys/bus/coresight/devices/
- ultra_smb0 ultra_smb1 ultra_smb2 ultra_smb3
+The ``ultra_smb<N>`` names SMB device associated with SCCL.::
- $# ls /sys/bus/coresight/devices/ultra_smb0
- enable_sink mgmt
- $# ls /sys/bus/coresight/devices/ultra_smb0/mgmt
- buf_size buf_status read_pos write_pos
+Key file items are:
- ``read_pos``: Shows the value on the read pointer register.
- ``write_pos``: Shows the value on the write pointer register.
- ``buf_status``: Shows the value on the status register.
BIT(0) is zero value which means the buffer is empty.
- ``buf_size``: Shows the buffer size of each device.
+Firmware Bindings +-----------------
+The device is only supported with ACPI. Its binding describes device +identifier, resource information and graph structure.
+The device is identified as ACPI HID "HISI03A1". Device resources are allocated +using the _CRS method. Each device must present two base address; the first one +is the configuration base address of the device, the second one is the 32-bit +base address of shared system memory.
+Example::
- Device(USMB) { \
Name(_HID, "HISI03A1") \Name(_CRS, ResourceTemplate() { \QWordMemory (ResourceConsumer, , MinFixed, MaxFixed, NonCacheable, \ReadWrite, 0x0, 0x95100000, 0x951FFFFF, 0x0, 0x100000) \QWordMemory (ResourceConsumer, , MinFixed, MaxFixed, Cacheable, \ReadWrite, 0x0, 0x50000000, 0x53FFFFFF, 0x0, 0x4000000) \}) \Name(_DSD, Package() { \ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), \- /* Use CoreSight Graph ACPI bindings to describe connections topology */
Package() { \0, \1, \Package() { \1, \ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"), \8, \Package() {0x8, 0, \_SB.S00.SL11.CL28.F008, 0}, \Package() {0x9, 0, \_SB.S00.SL11.CL29.F009, 0}, \Package() {0xa, 0, \_SB.S00.SL11.CL2A.F010, 0}, \Package() {0xb, 0, \_SB.S00.SL11.CL2B.F011, 0}, \Package() {0xc, 0, \_SB.S00.SL11.CL2C.F012, 0}, \Package() {0xd, 0, \_SB.S00.SL11.CL2D.F013, 0}, \Package() {0xe, 0, \_SB.S00.SL11.CL2E.F014, 0}, \Package() {0xf, 0, \_SB.S00.SL11.CL2F.F015, 0}, \} \} \}) \- }
This doc LGTM, thanks.
For this doc,
Reviewed-by: Bagas Sanjaya bagasdotme@gmail.com
Thanks for your comments.
Best regards, Junhao.
-
hejunhao