From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 41B0E23237F; Mon, 10 Mar 2025 17:46:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741628772; cv=none; b=CL9+cF67vUp5Q01JYbKUxYx/l2HE7d1e7LxdaUstmEMB9MdAdel11sqOMMz2aeC3Adcd4hlUb9WHJiONzvkm9WtkuRKSzOmO5YnO5waApHapNxPVbdMk8kvpxTfS9QFPXUCD0PnzDl401ksipdAheOaAB7JL/zX8iSRS6BzVfJc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741628772; c=relaxed/simple; bh=8eE6E7mIVk335XMnlFsG/3lAJMFI57i7bqriiHQT1xM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rz5ok4Z5+SVAaGgvH+6wmjT7Gdx/D4I0U3uwYShUNPYViy72q70dUN/Te/rXrvNUu+2RJ36wtKp0VLRI7KHH0vMEo93SL8qRRZJrwjKp1Alr1IUdCK5zPFw+e/FuBZ1/zFqQ+NjtxMxat0meQFr3XCIx25CfjzRSONyw0AfxDgU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=PKn87RzA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="PKn87RzA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7738C4CEE5; Mon, 10 Mar 2025 17:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1741628772; bh=8eE6E7mIVk335XMnlFsG/3lAJMFI57i7bqriiHQT1xM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PKn87RzAvYqLK4VpWzGCC27rRS6iZ+ZLk5nwKv6KLrJ+pNscfWW3Pms4jaZpvHEnG R8YIZjpErY3H0C0HWt34pSM87fc6gT7TsXcECTqyo9kg/fynvgt8iV9faDDUBegdl/ xX2A6uFvscTwIrVyVFZnIxHJN6yva7dYF0BbNOz8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dhananjay Ugwekar , "Gautham R. Shenoy" , Mario Limonciello , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 5.15 063/620] cpufreq: ACPI: Fix max-frequency computation Date: Mon, 10 Mar 2025 17:58:29 +0100 Message-ID: <20250310170548.071004074@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250310170545.553361750@linuxfoundation.org> References: <20250310170545.553361750@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gautham R. Shenoy [ Upstream commit 0834667545962ef1c5e8684ed32b45d9c574acd3 ] Commit 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies") introduced an assumption in acpi_cpufreq_cpu_init() that the first entry in the P-state table was the nominal frequency. This assumption is incorrect. The frequency corresponding to the P0 P-State need not be the same as the nominal frequency advertised via CPPC. Since the driver is using the CPPC.highest_perf and CPPC.nominal_perf to compute the boost-ratio, it makes sense to use CPPC.nominal_freq to compute the max-frequency. CPPC.nominal_freq is advertised on platforms supporting CPPC revisions 3 or higher. Hence, fallback to using the first entry in the P-State table only on platforms that do not advertise CPPC.nominal_freq. Fixes: 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies") Tested-by: Dhananjay Ugwekar Signed-off-by: Gautham R. Shenoy Reviewed-by: Mario Limonciello Link: https://patch.msgid.link/20250113044107.566-1-gautham.shenoy@amd.com [ rjw: Retain reverse X-mas tree ordering of local variable declarations ] [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/cpufreq/acpi-cpufreq.c | 36 +++++++++++++++++++++++++--------- 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 28467d83c7452..4a31bd90406c9 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -630,7 +630,14 @@ static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c) #endif #ifdef CONFIG_ACPI_CPPC_LIB -static u64 get_max_boost_ratio(unsigned int cpu) +/* + * get_max_boost_ratio: Computes the max_boost_ratio as the ratio + * between the highest_perf and the nominal_perf. + * + * Returns the max_boost_ratio for @cpu. Returns the CPPC nominal + * frequency via @nominal_freq if it is non-NULL pointer. + */ +static u64 get_max_boost_ratio(unsigned int cpu, u64 *nominal_freq) { struct cppc_perf_caps perf_caps; u64 highest_perf, nominal_perf; @@ -653,6 +660,9 @@ static u64 get_max_boost_ratio(unsigned int cpu) nominal_perf = perf_caps.nominal_perf; + if (nominal_freq) + *nominal_freq = perf_caps.nominal_freq; + if (!highest_perf || !nominal_perf) { pr_debug("CPU%d: highest or nominal performance missing\n", cpu); return 0; @@ -665,8 +675,12 @@ static u64 get_max_boost_ratio(unsigned int cpu) return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf); } + #else -static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; } +static inline u64 get_max_boost_ratio(unsigned int cpu, u64 *nominal_freq) +{ + return 0; +} #endif static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) @@ -676,9 +690,9 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) struct acpi_cpufreq_data *data; unsigned int cpu = policy->cpu; struct cpuinfo_x86 *c = &cpu_data(cpu); + u64 max_boost_ratio, nominal_freq = 0; unsigned int valid_states = 0; unsigned int result = 0; - u64 max_boost_ratio; unsigned int i; #ifdef CONFIG_SMP static int blacklisted; @@ -828,16 +842,20 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) } freq_table[valid_states].frequency = CPUFREQ_TABLE_END; - max_boost_ratio = get_max_boost_ratio(cpu); + max_boost_ratio = get_max_boost_ratio(cpu, &nominal_freq); if (max_boost_ratio) { - unsigned int freq = freq_table[0].frequency; + unsigned int freq = nominal_freq; /* - * Because the loop above sorts the freq_table entries in the - * descending order, freq is the maximum frequency in the table. - * Assume that it corresponds to the CPPC nominal frequency and - * use it to set cpuinfo.max_freq. + * The loop above sorts the freq_table entries in the + * descending order. If ACPI CPPC has not advertised + * the nominal frequency (this is possible in CPPC + * revisions prior to 3), then use the first entry in + * the pstate table as a proxy for nominal frequency. */ + if (!freq) + freq = freq_table[0].frequency; + policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT; } else { /* -- 2.39.5