From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC5EEC07E9E for ; Mon, 5 Jul 2021 15:36:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A917F61176 for ; Mon, 5 Jul 2021 15:36:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234022AbhGEPiq (ORCPT ); Mon, 5 Jul 2021 11:38:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:36188 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232792AbhGEPg5 (ORCPT ); Mon, 5 Jul 2021 11:36:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 425E961995; Mon, 5 Jul 2021 15:32:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625499130; bh=CI4jYarbWrt2iBArbBgIdntQThqTJhVm7C3TvtGzvqw=; h=From:To:Cc:Subject:Date:From; b=oxBrLpx/p7qS7+/w0IP5SBqxoOzjnK3Gcu9KdFOeHB1XK/H6v/Zdk/mZf9zMIHtX9 nnZZX7fPRRbU5Eq+ngPNArDpqurDn59FNJ9ZYwyDXvcQbTYFkm9riwaIHvlMzbvrqS 7Ejj+KSMBmK17MvPxm4CzX63hK+iPum3B6rk/Mg465dKSeKaIzzC6g2Rh/8OCxFL2u iFcDjqV64vk9+xksm3bcz07QSzvgruP0bLujAsK7vQjUgi8F/9Ua6fkJP2EgvBiepv DNRUKG8Jojw/2MKg0NPcCDJyZOG+fEAqnVD0Bs5hwuWtiZQgZFlIa+iY8rY2ZrFN3r 9PS41SXGY7XcA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Mario Limonciello , Prike Liang , Alex Deucher , "Rafael J . Wysocki" , Sasha Levin , linux-acpi@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 1/7] ACPI: processor idle: Fix up C-state latency if not ordered Date: Mon, 5 Jul 2021 11:32:01 -0400 Message-Id: <20210705153208.1522553-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mario Limonciello [ Upstream commit 65ea8f2c6e230bdf71fed0137cf9e9d1b307db32 ] Generally, the C-state latency is provided by the _CST method or FADT, but some OEM platforms using AMD Picasso, Renoir, Van Gogh, and Cezanne set the C2 latency greater than C3's which causes the C2 state to be skipped. That will block the core entering PC6, which prevents S0ix working properly on Linux systems. In other operating systems, the latency values are not validated and this does not cause problems by skipping states. To avoid this issue on Linux, detect when latencies are not an arithmetic progression and sort them. Link: https://gitlab.freedesktop.org/agd5f/linux/-/commit/026d186e4592c1ee9c1cb44295912d0294508725 Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1230#note_712174 Suggested-by: Prike Liang Suggested-by: Alex Deucher Signed-off-by: Mario Limonciello [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/processor_idle.c | 40 +++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 175c86bee3a9..69fec2d3a1f5 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -28,6 +28,7 @@ #include #include #include /* need_resched() */ +#include #include #include #include @@ -572,10 +573,37 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr, return; } +static int acpi_cst_latency_cmp(const void *a, const void *b) +{ + const struct acpi_processor_cx *x = a, *y = b; + + if (!(x->valid && y->valid)) + return 0; + if (x->latency > y->latency) + return 1; + if (x->latency < y->latency) + return -1; + return 0; +} +static void acpi_cst_latency_swap(void *a, void *b, int n) +{ + struct acpi_processor_cx *x = a, *y = b; + u32 tmp; + + if (!(x->valid && y->valid)) + return; + tmp = x->latency; + x->latency = y->latency; + y->latency = tmp; +} + static int acpi_processor_power_verify(struct acpi_processor *pr) { unsigned int i; unsigned int working = 0; + unsigned int last_latency = 0; + unsigned int last_type = 0; + bool buggy_latency = false; pr->power.timer_broadcast_on_state = INT_MAX; @@ -599,12 +627,24 @@ static int acpi_processor_power_verify(struct acpi_processor *pr) } if (!cx->valid) continue; + if (cx->type >= last_type && cx->latency < last_latency) + buggy_latency = true; + last_latency = cx->latency; + last_type = cx->type; lapic_timer_check_state(i, pr, cx); tsc_check_state(cx->type); working++; } + if (buggy_latency) { + pr_notice("FW issue: working around C-state latencies out of order\n"); + sort(&pr->power.states[1], max_cstate, + sizeof(struct acpi_processor_cx), + acpi_cst_latency_cmp, + acpi_cst_latency_swap); + } + lapic_timer_propagate_broadcast(pr); return (working); -- 2.30.2