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From:   Perry Yuan <perry.yuan@amd.com>
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Subject: [PATCH v5 9/9] Documentation: introduce amd pstate active mode kernel command line options
Date:   Tue, 29 Nov 2022 01:03:14 +0800
Message-ID: <20221128170314.2276636-10-perry.yuan@amd.com>
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AMD Pstate driver support another fimware based autonomous mode
with "amd_pstate=active" added to the kernel command line.
In autonomous mode SMU firmware decides frequencies at 1 ms timescale
based on workload utilization, usage in other IPs, infrastructure
limits such as power, thermals and so on.

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..8fa0d45add03 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 instace 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