From nobody Fri Dec 19 08:06:32 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 99E3CC4332F for ; Mon, 14 Nov 2022 09:03:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236718AbiKNJDC (ORCPT ); Mon, 14 Nov 2022 04:03:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236702AbiKNJCy (ORCPT ); Mon, 14 Nov 2022 04:02:54 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8813F5FFE; Mon, 14 Nov 2022 01:02:52 -0800 (PST) Received: from dggpeml500023.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4N9jxg2jBRzmVys; Mon, 14 Nov 2022 17:02:31 +0800 (CST) Received: from dggpeml500002.china.huawei.com (7.185.36.158) by dggpeml500023.china.huawei.com (7.185.36.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 14 Nov 2022 17:02:50 +0800 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 15.1.2375.31; Mon, 14 Nov 2022 17:02:50 +0800 From: Junhao He To: , , , , , CC: , , , , , , , , , , Subject: [PATCH v13 2/2] Documentation: Add document for UltraSoc SMB drivers Date: Mon, 14 Nov 2022 17:03:16 +0800 Message-ID: <20221114090316.63157-3-hejunhao3@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20221114090316.63157-1-hejunhao3@huawei.com> References: <20221114090316.63157-1-hejunhao3@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) 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 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 Signed-off-by: Junhao He Reviewed-by: Jonathan Cameron --- .../sysfs-bus-coresight-devices-ultra_smb | 31 +++++++ .../trace/coresight/ultrasoc-smb.rst | 82 +++++++++++++++++++ 2 files changed, 113 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..deaefd508105 --- /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: November 2022 +KernelVersion: 6.2 +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: November 2022 +KernelVersion: 6.2 +Contact: Junhao He +Description: (Read) Shows the buffer size of each UltraSoc SMB device. + +What: /sys/bus/coresight/devices/ultra_smb/mgmt/buf_status +Date: November 2022 +KernelVersion: 6.2 +Contact: Junhao He +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/mgmt/read_pos +Date: November 2022 +KernelVersion: 6.2 +Contact: Junhao He +Description: (Read) Shows the value held by UltraSoc SMB Read Pointer regi= ster. + +What: /sys/bus/coresight/devices/ultra_smb/mgmt/write_pos +Date: November 2022 +KernelVersion: 6.2 +Contact: Junhao He +Description: (Read) Shows the value held by UltraSoc SMB Write Pointer reg= ister. diff --git a/Documentation/trace/coresight/ultrasoc-smb.rst b/Documentation= /trace/coresight/ultrasoc-smb.rst new file mode 100644 index 000000000000..b7fe3f5c7f53 --- /dev/null +++ b/Documentation/trace/coresight/ultrasoc-smb.rst @@ -0,0 +1,82 @@ +.. 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: 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`` 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 regis= ter. + * ``write_pos``: Shows the value held by UltraSoc SMB Write Pointer reg= ister. + * ``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 u= sing +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 32bits base +address of shared system memory. + +examples:: + + 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