From: Qi Liu <liuqi115@huawei.com>
This patch bring in documentation for UltraSoc SMB drivers.
It simply describes the device, sysfs interface and the
firmware bindings.
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Signed-off-by: Junhao He <hejunhao3@huawei.com>
---
.../sysfs-bus-coresight-devices-ultra_smb | 31 +++++++
.../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++
2 files changed, 111 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb
create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst
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..7804aef4b40b
--- /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: October 2022
+KernelVersion: 6.1
+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: October 2022
+KernelVersion: 6.1
+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: October 2022
+KernelVersion: 6.1
+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: October 2022
+KernelVersion: 6.1
+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: October 2022
+KernelVersion: 6.1
+Contact: Junhao He <hejunhao3@huawei.com>
+Description: (Read) Shows the value held by UltraSoc SMB Write Pointer register.
diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst b/Documentation/trace/coresight/ultrasoc-smb.rst
new file mode 100644
index 000000000000..6d28ef0f6c88
--- /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 <liuqi115@huawei.com>
+ :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
+---------------------------
+
+SMB device is only supported with ACPI, and ACPI binding of SMB device
+describes SMB device indentifier, resource information and graph structure.
+
+SMB is identified by ACPI HID "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}, \
+ } \
+ } \
+ }) \
+ }
--
2.33.0On Mon, 7 Nov 2022 21:06:24 +0800 Junhao He <hejunhao3@huawei.com> wrote: > From: Qi Liu <liuqi115@huawei.com> > > This patch bring in documentation for UltraSoc SMB drivers. > It simply describes the device, sysfs interface and the > firmware bindings. > > Signed-off-by: Qi Liu <liuqi115@huawei.com> > Signed-off-by: Junhao He <hejunhao3@huawei.com> > --- > .../sysfs-bus-coresight-devices-ultra_smb | 31 +++++++ > .../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++ > 2 files changed, 111 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb > create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst > > 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..7804aef4b40b > --- /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: October 2022 > +KernelVersion: 6.1 Update to 6.2 as this will hopefully go in next merge window and it makes life easier for the maintainer if they don't need to fix all these up. > +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. Rest looks good to me, (not an expert on this stuff though!) Jonathan
Hi Jonathan, On 2022/11/7 22:33, Jonathan Cameron wrote: > On Mon, 7 Nov 2022 21:06:24 +0800 > Junhao He <hejunhao3@huawei.com> wrote: > >> From: Qi Liu <liuqi115@huawei.com> >> >> This patch bring in documentation for UltraSoc SMB drivers. >> It simply describes the device, sysfs interface and the >> firmware bindings. >> >> Signed-off-by: Qi Liu <liuqi115@huawei.com> >> Signed-off-by: Junhao He <hejunhao3@huawei.com> >> --- >> .../sysfs-bus-coresight-devices-ultra_smb | 31 +++++++ >> .../trace/coresight/ultrasoc-smb.rst | 80 +++++++++++++++++++ >> 2 files changed, 111 insertions(+) >> create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb >> create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst >> >> 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..7804aef4b40b >> --- /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: October 2022 >> +KernelVersion: 6.1 > Update to 6.2 as this will hopefully go in next merge window and it makes > life easier for the maintainer if they don't need to fix all these up. Ok, i will fix in next version. Thanks. >> +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. > Rest looks good to me, (not an expert on this stuff though!) > > Jonathan > . > Best regards, Junhao.
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