This patch bring in a documentation for UltraSoc SMB drivers.
It simple descripts the device, sysfs interface and the
firmware bindings.
Signed-off-by: Qi Liu <[email protected]>
---
.../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++
1 file changed, 80 insertions(+)
create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst
diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst b/Documentation/trace/coresight/ultrasoc-smb.rst
new file mode 100644
index 000000000000..b4cfea82deb8
--- /dev/null
+++ b/Documentation/trace/coresight/ultrasoc-smb.rst
@@ -0,0 +1,80 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================================
+UltraSoc - HW Assisted Tracing on SoC
+======================================
+ :Author: Qi Liu <[email protected]>
+ :Date: March 2022
+
+Introduction
+------------
+
+UltraSoc SMB is a per SCCL(Super CPU Cluster) hardware, and it provides a way to buffer and store
+CPU trace messages in a region of shared system memory. SMB is plugged as
+a coresight sink device and the corresponding trace generators (ETM) are
+plugged in as source devices.
+
+Sysfs files and directories
+---------------------------
+
+The SMB devices appear on the existing coresight bus alongside the other
+coresight devices::
+
+ $# ls /sys/bus/coresight/devices/
+ ultra_smb0 ultra_smb1 ultra_smb2 ultra_smb3
+
+The ``ultra_smb<N>`` named SMB 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 held by UltraSoc SMB Read Pointer register.
+ * ``write_pos``: Shows the value held by UltraSoc SMB Write Pointer register.
+ * ``buf_status``: Shows the value held by UltraSoc SMB status register.
+ BIT(0) is zero means buffer is empty.
+ * ``buf_size``: Shows the buffer size of each UltraSoc SMB device.
+
+Firmware Bindings
+---------------------------
+
+Firmware binding of SMB device describes SMB device indentifier, resource
+information and graph structure.
+
+SMB is platform device and device id is "HISI03A1", resource of device is
+declared using the _CRS method. Each SMB must present two base address,
+the first one is the configuration base address of SMB device, the second
+one is the base address of shared system memory.
+
+examples::
+
+ Device(USMB) { \
+ Name(_HID, "HISI03A1") \
+ Name(_CRS, ResourceTemplate() { \
+ MEM_RESRC(0x95100000, 0x951FFFFF, 0x100000) \
+ MEM_RESRC(0x50000000, 0x53FFFFFF, 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}, \
+ } \
+ } \
+ }) \
+ }
--
2.24.0
Hi Qi
Please find my comments below.
On 06/06/2022 14:02, Qi Liu wrote:
> This patch bring in a documentation for UltraSoc SMB drivers.
> It simple descripts the device, sysfs interface and the
> firmware bindings.
>
> Signed-off-by: Qi Liu <[email protected]>
> ---
> .../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++
> 1 file changed, 80 insertions(+)
> create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst
>
> diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst b/Documentation/trace/coresight/ultrasoc-smb.rst
> new file mode 100644
> index 000000000000..b4cfea82deb8
> --- /dev/null
> +++ b/Documentation/trace/coresight/ultrasoc-smb.rst
> @@ -0,0 +1,80 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +======================================
> +UltraSoc - HW Assisted Tracing on SoC
> +======================================
> + :Author: Qi Liu <[email protected]>
> + :Date: March 2022
> +
> +Introduction
> +------------
> +
> +UltraSoc SMB is a per SCCL(Super CPU Cluster) hardware, and it provides a way to buffer and store
minor nit: alignment.
> +CPU trace messages in a region of shared system memory. SMB is plugged as
> +a coresight sink device and the corresponding trace generators (ETM) are
> +plugged in as source devices.
> +
--8>---
> +Sysfs files and directories
> +---------------------------
> +
> +The SMB devices appear on the existing coresight bus alongside the other
> +coresight devices::
> +
> + $# ls /sys/bus/coresight/devices/
> + ultra_smb0 ultra_smb1 ultra_smb2 ultra_smb3
> +
> +The ``ultra_smb<N>`` named SMB 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
> +
These should also be placed in, with the appropriate format.
Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb
> +*Key file items are:-*
> + * ``read_pos``: Shows the value held by UltraSoc SMB Read Pointer register.
> + * ``write_pos``: Shows the value held by UltraSoc SMB Write Pointer register.
> + * ``buf_status``: Shows the value held by UltraSoc SMB status register.
> + BIT(0) is zero means buffer is empty.
> + * ``buf_size``: Shows the buffer size of each UltraSoc SMB device.
> +
> +Firmware Bindings
> +---------------------------
> +
> +Firmware binding of SMB device describes SMB device indentifier, resource
> +information and graph structure.
Please could you mention that this is only supported with ACPI here ?
> +
> +SMB is platform device and device id is "HISI03A1", resource of device is
> +declared using the _CRS method. Each SMB must present two base address,
Simply say, the device is identified by ACPI HID "HISI03A1".
> +the first one is the configuration base address of SMB device, the second
> +one is the base address of shared system memory.
> +
> +examples::
> +
> + Device(USMB) { \
> + Name(_HID, "HISI03A1") \
> + Name(_CRS, ResourceTemplate() { \
> + MEM_RESRC(0x95100000, 0x951FFFFF, 0x100000) \
> + MEM_RESRC(0x50000000, 0x53FFFFFF, 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}, \
> + } \
> + } \
> + }) \
> + }
Rest looks fine to me
Suzuki
Hi Suzuki,
Thanks for your review.
On 2022/6/6 23:16, Suzuki K Poulose wrote:
> Hi Qi
>
> Please find my comments below.
>
> On 06/06/2022 14:02, Qi Liu wrote:
>> This patch bring in a documentation for UltraSoc SMB drivers.
>> It simple descripts the device, sysfs interface and the
>> firmware bindings.
>>
>> Signed-off-by: Qi Liu <[email protected]>
>> ---
>> .../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++
>> 1 file changed, 80 insertions(+)
>> create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst
>>
>> diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst
>> b/Documentation/trace/coresight/ultrasoc-smb.rst
>> new file mode 100644
>> index 000000000000..b4cfea82deb8
>> --- /dev/null
>> +++ b/Documentation/trace/coresight/ultrasoc-smb.rst
>> @@ -0,0 +1,80 @@
>> +.. SPDX-License-Identifier: GPL-2.0
>> +
>> +======================================
>> +UltraSoc - HW Assisted Tracing on SoC
>> +======================================
>> + :Author: Qi Liu <[email protected]>
>> + :Date: March 2022
>> +
>> +Introduction
>> +------------
>> +
>> +UltraSoc SMB is a per SCCL(Super CPU Cluster) hardware, and it
>> provides a way to buffer and store
>
> minor nit: alignment.
>
thanks, will pay attention to this.
>> +CPU trace messages in a region of shared system memory. SMB is
>> plugged as
>> +a coresight sink device and the corresponding trace generators (ETM) are
>> +plugged in as source devices.
>> +
>
> --8>---
>
>> +Sysfs files and directories
>> +---------------------------
>> +
>> +The SMB devices appear on the existing coresight bus alongside the other
>> +coresight devices::
>> +
>> + $# ls /sys/bus/coresight/devices/
>> + ultra_smb0 ultra_smb1 ultra_smb2 ultra_smb3
>> +
>> +The ``ultra_smb<N>`` named SMB 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
>> +
>
> These should also be placed in, with the appropriate format.
>
> Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb
>
got it, will add this document, thanks.
>
>
>> +*Key file items are:-*
>> + * ``read_pos``: Shows the value held by UltraSoc SMB Read Pointer
>> register.
>> + * ``write_pos``: Shows the value held by UltraSoc SMB Write
>> Pointer register.
>> + * ``buf_status``: Shows the value held by UltraSoc SMB status
>> register.
>> + BIT(0) is zero means buffer is empty.
>> + * ``buf_size``: Shows the buffer size of each UltraSoc SMB device.
>> +
>> +Firmware Bindings
>> +---------------------------
>> +
>> +Firmware binding of SMB device describes SMB device indentifier,
>> resource
>> +information and graph structure.
>
> Please could you mention that this is only supported with ACPI here ?
>
sure, will add this next time.
>> +
>> +SMB is platform device and device id is "HISI03A1", resource of
>> device is
>> +declared using the _CRS method. Each SMB must present two base address,
>
> Simply say, the device is identified by ACPI HID "HISI03A1".
>
ok, will modify this.
>> +the first one is the configuration base address of SMB device, the
>> second
>> +one is the base address of shared system memory.
>> +
>> +examples::
>> +
>> + Device(USMB) { \
>> + Name(_HID, "HISI03A1") \
>> + Name(_CRS, ResourceTemplate() { \
>> + MEM_RESRC(0x95100000, 0x951FFFFF, 0x100000) \
>> + MEM_RESRC(0x50000000, 0x53FFFFFF, 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}, \
>> + } \
>> + } \
>> + }) \
>> + }
>
> Rest looks fine to me
>
> Suzuki
>
Thanks,
Qi
> .