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[176.93.242.43]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-38ecb5f6666sm55070071fa.15.2026.04.25.00.25.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 25 Apr 2026 00:25:44 -0700 (PDT) From: Artem Bityutskiy To: "Rafael J. Wysocki" Cc: Linux PM Mailing List Subject: [PATCH 0/3] intel_idle: Drop C-states redundant when PC6 is disabled Date: Sat, 25 Apr 2026 10:25:28 +0300 Message-ID: <20260425072532.358365-1-dedekind1@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Artem Bityutskiy This patch series drops redundant requestable C-states when PC6 is disabled in BIOS. For example, Granite Rapids Xeon has two C6 flavors: C6 and C6P. C6 allows only core C6 (CC6), while C6P allows both CC6 and package C6 (PC6). When PC6 is disabled, C6P becomes identical to C6 and is therefore redundant. Refer to patch 3 for the full rationale and details. Patches 1 and 2 prepare the code for patch 3. They introduce no functional changes, only restructure it to improve readability and maintainability. For more information about Granite Rapids C6 vs C6P, refer to this article: https://github.com/intel/pepc/blob/main/docs/misc-c6p-c6sp.md Thanks, Artem. Artem Bityutskiy (3): intel_idle: Add constants for MSR_PKG_CST_CONFIG_CONTROL intel_idle: Introduce a helper for checking PC6 intel_idle: Drop C-states redundant when PC6 is disabled drivers/idle/intel_idle.c | 104 +++++++++++++++++++++++++++++--------- 1 file changed, 81 insertions(+), 23 deletions(-) -- 2.53.0