Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Received-SPF: Pass (protection.outlook.com: domain of amd.com designates
 165.204.84.17 as permitted sender) receiver=protection.outlook.com;
 client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C
From:   Perry Yuan <perry.yuan@amd.com>
To:     <rafael.j.wysocki@intel.com>, <Mario.Limonciello@amd.com>,
        <ray.huang@amd.com>, <viresh.kumar@linaro.org>
CC:     <Deepak.Sharma@amd.com>, <Nathan.Fontenot@amd.com>,
        <Alexander.Deucher@amd.com>, <Shimmer.Huang@amd.com>,
        <Xiaojian.Du@amd.com>, <Li.Meng@amd.com>, <wyes.karny@amd.com>,
        <linux-pm@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH v10 10/12] Documentation: introduce amd pstate active mode kernel command line options
Date:   Fri, 6 Jan 2023 14:14:18 +0800
Message-ID: <20230106061420.95715-11-perry.yuan@amd.com>
In-Reply-To: <20230106061420.95715-1-perry.yuan@amd.com>
References: <20230106061420.95715-1-perry.yuan@amd.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jan 2023 06:16:23.1890
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: d990c032-4419-499a-da54-08daefad88f7
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com]
X-MS-Exchange-CrossTenant-AuthSource: DS1PEPF0000E633.namprd02.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB6054
X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,
        RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS autolearn=ham
        autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

AMD Pstate driver support another firmware based autonomous mode
with "amd_pstate=active" added to the kernel command line.
In autonomous mode SMU firmware decides frequencies at runtime
based on workload utilization, usage in other IPs, infrastructure
limits such as power, thermals and so on.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 Documentation/admin-guide/kernel-parameters.txt | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 42af9ca0127e..73a02816f6f8 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -6970,3 +6970,10 @@
 			  management firmware translates the requests into actual
 			  hardware states (core frequency, data fabric and memory
 			  clocks etc.)
+			active
+			  Use amd_pstate_epp driver instance as the scaling driver,
+			  driver provides a hint to the hardware if software wants
+			  to bias toward performance (0x0) or energy efficiency (0xff)
+			  to the CPPC firmware. then CPPC power algorithm will
+			  calculate the runtime workload and adjust the realtime cores
+			  frequency.
-- 
2.34.1