From nobody Mon Sep 15 07:39:46 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10AF1C3DA78 for ; Sat, 14 Jan 2023 10:13:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230014AbjANKNa (ORCPT ); Sat, 14 Jan 2023 05:13:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44558 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229843AbjANKNY (ORCPT ); Sat, 14 Jan 2023 05:13:24 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9FCC176BD; Sat, 14 Jan 2023 02:13:22 -0800 (PST) Received: from dggpeml500002.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4NvDbg2z36zJrVW; Sat, 14 Jan 2023 18:11:59 +0800 (CST) Received: from localhost.localdomain (10.69.192.56) by dggpeml500002.china.huawei.com (7.185.36.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.34; Sat, 14 Jan 2023 18:13:19 +0800 From: Junhao He To: , , , , CC: , , , , , , , , , , , Subject: [PATCH v16 2/2] Documentation: Add document for UltraSoc SMB driver Date: Sat, 14 Jan 2023 18:13:02 +0800 Message-ID: <20230114101302.62320-3-hejunhao3@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20230114101302.62320-1-hejunhao3@huawei.com> References: <20230114101302.62320-1-hejunhao3@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpeml500002.china.huawei.com (7.185.36.158) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Qi Liu Bring in documentation for UltraSoc SMB driver. It simply describes the device, sysfs interface and the firmware bindings. Signed-off-by: Qi Liu Signed-off-by: Junhao He Reviewed-by: Jonathan Cameron Reviewed-by: Bagas Sanjaya --- .../sysfs-bus-coresight-devices-ultra_smb | 31 +++++++ .../trace/coresight/ultrasoc-smb.rst | 83 +++++++++++++++++++ 2 files changed, 114 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-u= ltra_smb create mode 100644 Documentation/trace/coresight/ultrasoc-smb.rst diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_sm= b b/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb new file mode 100644 index 000000000000..f560918ae738 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-ultra_smb @@ -0,0 +1,31 @@ +What: /sys/bus/coresight/devices/ultra_smb/enable_sink +Date: January 2023 +KernelVersion: 6.3 +Contact: Junhao He +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/mgmt/buf_size +Date: January 2023 +KernelVersion: 6.3 +Contact: Junhao He +Description: (RO) Shows the buffer size of each UltraSoc SMB device. + +What: /sys/bus/coresight/devices/ultra_smb/mgmt/buf_status +Date: January 2023 +KernelVersion: 6.3 +Contact: Junhao He +Description: (RO) Shows the value of UltraSoc SMB status register. + BIT(0) is zero means buffer is empty. + +What: /sys/bus/coresight/devices/ultra_smb/mgmt/read_pos +Date: January 2023 +KernelVersion: 6.3 +Contact: Junhao He +Description: (RO) Shows the value of UltraSoc SMB Read Pointer register. + +What: /sys/bus/coresight/devices/ultra_smb/mgmt/write_pos +Date: January 2023 +KernelVersion: 6.3 +Contact: Junhao He +Description: (RO) Shows the value of 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..a05488a75ff0 --- /dev/null +++ b/Documentation/trace/coresight/ultrasoc-smb.rst @@ -0,0 +1,83 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D +UltraSoc - HW Assisted Tracing on SoC +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + :Author: Qi Liu + :Date: January 2023 + +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`` 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 allo= cated +using the _CRS method. Each device must present two base address; the firs= t 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, NonCacheabl= e, \ + 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}, \ + } \ + } \ + }) \ + } --=20 2.33.0